U.S. patent application number 10/816768 was filed with the patent office on 2005-11-10 for modified tgf-beta superfamily proteins.
This patent application is currently assigned to Stryker Corporation. Invention is credited to McCartney, John, Oppermann, Hermann, Tai, Mei-Sheng.
Application Number | 20050250936 10/816768 |
Document ID | / |
Family ID | 26800442 |
Filed Date | 2005-11-10 |
United States Patent
Application |
20050250936 |
Kind Code |
A1 |
Oppermann, Hermann ; et
al. |
November 10, 2005 |
Modified TGF-beta superfamily proteins
Abstract
The invention provides modified TGF-.beta. family proteins
having altered biological or biochemical properties, and methods
for making them. Specific modified protein constructs include
TGF-.beta. family member proteins that have N-terminal truncations,
"latent" proteins, fusion proteins and heterodimers.
Inventors: |
Oppermann, Hermann; (Medway,
MA) ; Tai, Mei-Sheng; (Shrewsbury, MA) ;
McCartney, John; (Holliston, MA) |
Correspondence
Address: |
FISH & NEAVE IP GROUP
ROPES & GRAY LLP
1251 AVENUE OF THE AMERICAS FL C3
NEW YORK
NY
10020-1105
US
|
Assignee: |
Stryker Corporation
|
Family ID: |
26800442 |
Appl. No.: |
10/816768 |
Filed: |
April 2, 2004 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10816768 |
Apr 2, 2004 |
|
|
|
09375333 |
Aug 16, 1999 |
|
|
|
60103418 |
Oct 7, 1998 |
|
|
|
Current U.S.
Class: |
530/399 |
Current CPC
Class: |
C07K 14/51 20130101;
A61P 19/08 20180101; A61P 19/02 20180101; A61P 37/02 20180101; A61P
19/00 20180101; C07K 2319/75 20130101; C07K 2319/00 20130101; A61K
38/00 20130101; C07K 14/47 20130101; A61P 21/00 20180101; A61P
19/10 20180101 |
Class at
Publication: |
530/399 |
International
Class: |
C07K 014/495 |
Claims
What is claimed is:
1. A biologically active TGF-.beta. family member fusion protein
competent to refold under suitable refolding conditions,
comprising: a TGF-.beta. family protein C-terminal seven cysteine
domain, comprising a finger 1 subdomain, a finger 2 subdomain, and
a heel subdomain; and a heterologous leader sequence domain
operatively linked to said C-terminal domain.
2. The fusion protein of claim 1 wherein said leader sequence is
selected from the group consisting of a tissue-targeting domain, a
molecular-targeting domain, a metal-binding domain, a
protein-binding domain, a ceramic-binding domain, a
hydroxyapatite-binding domain, and a collagen-binding domain.
3. The fusion protein of claim 2 wherein said tissue-targeting
domain binds to a bone matrix protein.
4. The fusion protein of claim 2 wherein said tissue-targeting
domain binds to a cell surface molecule.
5. The fusion protein of claim 4 wherein said cell surface molecule
is on an osteoprogenitor cell or a chondrocyte.
6. A latent TGF-.beta. family member fusion protein competent to
refold under suitable refolding conditions, comprising: a
TGF-.beta. family protein C-terminal seven cysteine domain,
comprising a finger 1 subdomain, a finger 2 subdomain, and a heel
subdomain; and a cleavable leader sequence operably linked to said
C-terminal domain wherein said leader sequence inhibits the
biological activity associated with said C-terminal domain, and
wherein said C-terminal domain becomes active upon cleavage of a
part or all of said leader sequence.
7. The fusion protein of claim 6 wherein a tissue-targeting domain
is embedded within said cleavable leader sequence, whereby cleavage
of the leader sequence will not cleave said tissue-targeting domain
from said C-terminal domain.
8. The fusion protein of claim 1 or 6 wherein said leader sequence
is separated from said C-terminal domain by at least seven
residues.
9. The fusion protein of claim 1 wherein said leader sequence is
derived from another TGF-.beta. family protein.
10. A biologically active TGF-.beta. family member protein mutant
competent to refold under suitable refolding conditions,
comprising: a TGF-.beta. family member protein C-terminal seven
cysteine domain, comprising a finger 1 subdomain, a finger 2
subdomain, and a heel subdomain; and a leader sequence domain
operatively linked to said C-terminal domain, whereby a part or all
of said leader sequence is truncated.
11. The protein mutant of claim 10 wherein said truncation is
carried out by protease cleavage.
12. The protein mutant of claim 11 wherein said protease is
trypsin.
13. The protein mutant of claim 10 wherein said truncation is
carried out by chemical cleavage.
14. The protein mutant of claim 13 wherein said chemical cleavage
is acid cleavage.
15. The protein mutant of claim 10 wherein at least one basic
residue of said leader sequence is removed.
16. The protein mutant of claim 10 wherein said protein mutant
consists essentially of amino acid sequence SEQ ID NO. 69.
17. A biologically active heterodimer of TGF-.beta. family member
proteins, comprising: a first subunit being a TGF-.beta. family
member fusion protein; and a second subunit selected from the group
consisting of a TGF-.beta. family member fusion protein different
from that of the first subunit and a wild type TGF-.beta. family
protein.
18. The heterodimer of claim 16, wherein said wild type TGF-.beta.
family protein is selected from the group consisting of
TGF-.beta.1, TGF-.beta.-2, TGF-.beta.3, TGF-.beta.4, TGF-.beta.5,
dpp, Vg-1, Vgr-1, 60A, BMP-2A, BMP-3, BMP-4, BMP-5, BMP-6,
Dorsalin, OP-1, OP-2, OP-3, GDF-1, GDF-3, GDF-9, Inhibin .alpha.,
Inhibin .beta.A and Inhibin .beta.B.
19. A method of purifying a heterodimer of TGF-.beta. family
proteins, said method comprising: (a) providing a first TGF-.beta.
family protein subunit; (b) providing a second TGF-.beta. family
protein subunit different from said first subunit; (c) mixing said
first subunit and said second subunit under suitable refolding
conditions to generate a mixture comprising (i) a first homodimer
comprising two of said first TGF-.beta. family protein subunits;
(ii) a second homodimer comprising two of said second TGF-.beta.
family protein subunits; and (iii) a heterodimer comprising one of
said first TGF-.beta. family subunits and one of said second
TGF-.beta. family subunits; wherein said heterodimer is separable
from said first homodimer and said second homodimer; and (d)
separating said heterodimer from said first homodimer and said
second homodimer.
Description
CONTINUING APPLICATION DATA
[0001] The instant utility application claims priority to U.S.
provisional patent application No. 60/103,418, filed on Oct. 7,
1998, the entire contents of which is incorporated herein by
reference; and the instant application is related to co-pending
utility applications U.S. Ser. Nos. ______ and ______ (Attorney
Docket Nos. STK-076 and STK-077) filed on even date herewith and
also based on the aforementioned provisional application, the
disclosures of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to recombinant proteins having
improved refolding properties, improved physical properties (such
as solubility and stability), improved biological activity,
including altered receptor binding, improved targeting
capabilities, latent forms of proteins, and methods for producing
such proteins. More particularly, the invention relates to
biosynthetic members of the TGF-.beta. super-family of
structurally-related proteins. Such modified protein constructs
include TGF-.beta. family member proteins that have N-terminal
truncations, "latent" proteins, fusion proteins and
heterodimers.
BACKGROUND OF THE INVENTION
[0003] The TGF-.beta. superfamily includes five distinct forms of
TGF-.beta. (Sporn and Roberts (1990) in Peptide Growth Factors and
Their Receptors, Sporn and Roberts, eds., Springer-Verlag: Berlin
pp. 419-472), as well as the differentiation factors vg-1 (Weeks
and Melton (1987) Cell 51: 861-867), DPP-C polypeptide (Padgett et
al. (1987) Nature 325: 81-84), the hormones activin and inhibin
(Mason et al. (1985) Nature 318: 659-663; Mason et al. (1987)
Growth Factors 1: 77-88), the Mullerian-inhibiting substance, MIS
(Cate et al. (1986) Cell 45:685-698), osteogenic and morphogenic
proteins OP-1 (PCT/US90/05903), OP-2 (PCT/US91/07654), OP-3
(PCT/WO94/10202), the BMPs, (see U.S. Pat. Nos. 4,877,864;
5,141,905; 5,013,649; 5,116,738; 5,108,922; 5,106,748; and
5,155,058), the developmentally regulated protein VGR-1 (Lyons et
al. (1989) Proc. Natl. Acad. Sci. USA 86: 4554-4558),
cartilage-derived growth factors CDMP-1, CDMP-2 and CDMP-3 (or
GDF-5, GDF-6 and GDF-7), and the growth/differentiation factors
GDF-1, GDF-3, GDF-9 and dorsalin-1 (McPherron et al. (1993) J.
Biol. Chem. 268: 3444-3449; Basler et al. (1993) Cell 73:
687-702).
[0004] The proteins of the TGF-.beta. superfamily are
disulfide-linked homo- or heterodimers that are expressed as large
precursor polypeptide chains containing a hydrophobic signal
sequence, a long and relatively poorly conserved N-terminal pro
region sequence of several hundred amino acids, a cleavage site,
and a mature domain comprising an N-terminal region that varies
among the family members and a more highly conserved C-terminal
region. This C-terminal region, present in the processed mature
proteins of all known family members, contains approximately 100
amino acids with a characteristic cysteine motif having a conserved
six or seven cysteine skeleton. Although the position of the
cleavage site between the mature and pro regions varies among the
family members, the cysteine pattern of the C-terminus of all of
the proteins is in the identical format, ending in the sequence
Cys-X-Cys-X (Sporn and Roberts (1990), supra).
[0005] Recombinant TGF-.beta.1 has been cloned (Derynck et al.
(1985) Nature 316: 701-705), and expressed in Chinese hamster ovary
cells (Gentry et al. (1987) Mol. Cell. Biol. 7: 3418-3427).
Additionally, recombinant human TGF-.beta.2 (deMartin et al. (1987)
EMBO J. 6: 3673), as well as human and porcine TGF-.beta.3 (Derynck
et al. (1988) EMBO J. 7: 3737-3743; Dijke et al. (1988) Proc. Natl.
Acad. Sci. USA 85: 4715), have been cloned. Expression levels of
the mature TGF-.beta.1 protein in COS cells have been increased by
substituting cysteine residues located in the pro region of the
TGF-.beta.1 precursor with serine residues (Brunner et al. (1989)
J. Biol. Chem. 264: 13660-13664).
[0006] A unifying feature of the biology of the proteins of the
TGF-.beta. superfamily is their ability to regulate developmental
processes. These structurally related proteins have been identified
as being involved in a variety of developmental events. For
example, TGF-.beta. and the polypeptides of the inhibin/activin
group appear to play a role in the regulation of cell growth and
differentiation. MIS causes regression of the Mullerian duct in
development of the mammalian male embryo, and dpp, the gene product
of the Drosophila decapentaplegic complex, is required for
appropriate dorsal-ventral specification. Similarly, Vg-1 is
involved in mesoderm induction in Xenopus, and Vgr-1 has been
identified in a variety of developing murine tissues. Regarding
bone formation, many of the proteins in the TGF-.beta. supergene
family, namely OP-1 and a subset of the BMPs, apparently play the
major role. OP-1 (BMP-7) and other osteogenic proteins have been
produced using recombinant techniques (U.S. Pat. No. 5,011,691 and
PCT Application No. US 90/05903) and shown to be able to induce
formation of true endochondral bone in vivo. BMP-2 has been
recombinantly produced in monkey COS-1 cells and Chinese hamster
ovary cells (Wang et al. (1990) Proc. Natl. Acad. Sci. USA 87:
2220-2224).
[0007] Recently the family of proteins taught as having osteogenic
activity as judged by the Sampath and Reddi bone formation assay
have been shown to be morphogenic, i.e., capable of inducing the
developmental cascade of tissue morphogenesis in a mature mammal
(See PCT Application No. US 92/01968). In particular, these
proteins are capable of inducing the proliferation of uncommitted
progenitor cells, and inducing the differentiation of these
stimulated progenitor cells in a tissue-specific manner under
appropriate environmental conditions. In addition, the morphogens
are capable of supporting the growth and maintenance of these
differentiated cells. These morphogenic activities allow the
proteins to initiate and maintain the developmental cascade of
tissue morphogenesis in an appropriate, morphogenically permissive
environment, stimulating stem cells to proliferate and
differentiate in a tissue-specific manner, and inducing the
progression of events that culminate in new tissue formation. These
morphogenic activities also allow the proteins to induce the
"redifferentiation" of cells previously stimulated to stray from
their differentiation path. Under appropriate environmental
conditions it is anticipated that these morphogens also may
stimulate the "redifferentiation" of committed cells.
[0008] The osteogenic proteins generally are classified in the art
as a subgroup of the TGF-.beta. superfamily of growth factors
(Hogan (1996), Genes & Development, 10:1580-1594), and are
variously termed "osteogenic proteins", "morphogenic proteins",
"morphogens", "bone morphogenic proteins" or "BMPs" are identified
by their ability to induce ectopic, endochondral bone
morphogenesis. Members of the morphogen family of proteins include
the mammalian osteogenic protein-1 (OP-1, also known as BMP-7, and
the Drosophila homolog 60A), osteogenic protein-2 (OP-2, also known
as BMP-8), osteogenic protein-3 (OP-3), BMP-2 (also known as BMP-2A
or CBMP-2A, and the Drosophila homolog DPP), BMP-3, BMP-4 (also
known as BMP-2B or CBMP-2B), BMP-5, BMP-6 and its murine homolog
Vgr-1, BMP-9, BMP-10, BMP-11, BMP-12, GDF3 (also known as Vgr2),
GDF-8, GDF-9, GDF-10, GDF-11, GDF-12, BMP-13, BMP-14, BMP-15, GDF-5
(also known as CDMP-1 or MP52), GDF-6 (also known as CDMP-2 or
BMP-13), GDF-7 (also known as CDMP-3 or BMP-12), the Xenopus
homolog Vg1 and NODAL, UNIVIN, SCREW, ADMP, and NEURAL.
[0009] Whether naturally-occurring or synthetically prepared,
osteogenic proteins, can induce recruitment and/or stimulation of
progenitor cells, thereby inducing their differentiation into
chondrocytes and osteoblasts, and further inducing differentiation
of intermediate cartilage, vascularization, bone formation,
remodeling, and, finally, marrow differentiation. Furthermore,
numerous practitioners have demonstrated the ability of these
osteogenic proteins, when admixed with either naturally-sourced
matrix materials such as collagen or synthetically-prepared
polymeric matrix materials, to induce bone formation, including
membraneous and endochondral bone formation, under conditions where
true replacement bone would not otherwise occur. For example, when
combined with a matrix material, these osteogenic proteins induce
formation of new bone in large segmental bone defects, spinal
fusions, clavarial defects, and fractures.
[0010] Bacterial and other prokaryotic expression systems are
relied on in the art as preferred means for generating recombinant
proteins. Prokaryotic systems such as E. coli are useful for
producing commercial quantities of proteins, as well as for
evaluating biological properties of naturally occurring or
biosynthetic mutants and analogs. Typically, an over-expressed
eukaryotic protein aggregates as an insoluble intracellular
precipitate ("inclusion body") in the prokaryote host cell. The
aggregated protein is then collected from the inclusion bodies,
solubilized using one or more standard denaturing agents, and then
allowed, or induced, to refold into a functional state. Proper
refolding to form a biologically active protein structure requires
proper formation of any disulfide bonds.
[0011] Chemical synthesis may also be employed to produce protein
constructs. Technology is widely available to permit routine,
automated assembly of peptide chains. Techniques are known in the
art which utilize enzymatic and chemical methods for coupling
peptide fragments into synthetic protein molecules. See, e.g.,
Hilvert, Chem. Biol. (1994) 1(4): 201-03; Muir et al., Proc. Nat'l
Acad. Sci. USA (1998) 95(12): 6705-10; Wallace, Curr. Opin.
Biotechnol. (1995) 6(4): 403-10; Miranda et al., Proc. Nat'l Acad.
Sci. USA (1999) 96(4): 1181-6; and Liu et al., Proc. Nat'l Acad.
Sci. USA (1994) 91(14): 6584-8.
[0012] For example, the tertiary and quaternary structure of both
TGF-.beta.2 and OP-1 have been determined. Although TGF-.beta.2 and
OP-1 exhibit only about 35% amino acid identity in their respective
amino acid sequences the tertiary and quaternary structures of both
molecules are strikingly similar. Both TGF-.beta.2 and OP-1 are
dimeric in nature and have a unique folding pattern involving six
of the seven C-terminal cysteine residues, as illustrated in FIG.
1A. FIG. 1A shows that in each subunit four cysteines bond to
generate an eight residue ring, and two additional cysteine
residues form a disulfide bond that passes through the ring to form
a knot-like structure. With a numbering scheme beginning with the
most N-terminal cysteine of the 7 conserved cysteine residues
assigned number 1, the 2nd and 6th conserved cysteine residues bond
to close one side of the eight residue ring while the 3rd and 7th
cysteine residues close the other side. The 1st and 5th conserved
cysteine residues bond through the center of the ring to form the
core of the knot. The 4th conserved cysteine forms an interchain
disulfide bond with the corresponding residue in the other
subunit.
[0013] The TGF-.beta.2 and OP-1 monomer subunits comprise three
major structural elements and an N-terminal region. The structural
elements are made up of regions of contiguous polypeptide chain
that possess over 50% secondary structure of the following types:
(1) loop, (2) .alpha.-helix and (3) .beta.-sheet. Furthermore, in
these regions the N-terminal and C-terminal strands are not more
than 7 A.degree. apart. The residues between the 1st and 2nd
conserved cysteines (FIG. 1A) form a structural region
characterized by an anti-parallel .beta.-sheet finger, referred to
herein as the finger 1 region (F1). A ribbon trace of the finger 1
peptide backbone is shown in FIG. 1B. Similarly the residues
between the 5th and 6th conserved cysteines in FIG. 1A also form an
anti-parallel .beta.-sheet finger, referred to herein as the finger
2 region (F2). A ribbon trace of the finger 2 peptide backbone is
shown in FIG. 1D. A .beta.-sheet finger is a single amino acid
chain, comprising a .beta.-strand that folds back on itself by
means of a .beta.-turn or some larger loop so that the entering and
exiting strands form one or more anti-parallel .beta.-sheet
structures. The third major structural region, involving the
residues between the 3rd and 4th conserved cysteines in FIG. 1A, is
characterized by a three turn .alpha.-helix referred to herein as
the heel region (H). A ribbon trace of the heel peptide backbone is
shown in FIG. 1C.
[0014] The organization of the monomer structure is similar to that
of a left hand where the knot region is located at the position
equivalent to the palm, finger 1 is equivalent to the index and
middle fingers, the .alpha.-helix is equivalent to the heel of the
hand, and finger 2 is equivalent to the ring and small fingers. The
N-terminal region (not well defined in the published structures) is
predicted to be located at a position roughly equivalent to the
thumb.
[0015] In the dimeric forms of both TGF-.beta.2 and OP-1, the
subunits are oriented such that the heel region of one subunit
contacts the finger regions of the other subunit with the knot
regions of the connected subunits forming the core of the molecule.
The 4th cysteine forms a disulfide bridge with its counterpart on
the second chain thereby equivalently linking the chains at the
center of the palms. The dimer thus formed is an ellipsoidal (cigar
shaped) molecule when viewed from the top looking down the two-fold
axis of symmetry between the subunits (FIG. 2A). Viewed from the
side, the molecule resembles a bent "cigar" since the two subunits
are oriented at a slight angle relative to each other (FIG.
2B).
[0016] However, not all solubilized heterologous proteins readily
refold. Despite careful manipulation of refolding, the yields of
properly folded, biologically active protein remain low. Many
TBF-.beta. family members, including BMPs, fall into the category
of poor refolder proteins. While some members of the TBF-.beta.
protein family can be folded efficiently in vitro as, for example,
when produced in E. coli or other prokaryotic hosts, many others,
including BMP5, BMP6, and BMP7, cannot. See, e.g., EP 0433225, U.S.
Pat. No. 5,399,677, U.S. Pat. No. 5,756,308 and U.S. Pat. No.
5,804,416.
[0017] A need remains for improved means for producing in vitro
recombinant BMPs and other TGF-.beta. family proteins using
prokaryotic as well as eukaryotic host cells.
SUMMARY OF THE INVENTION
[0018] The present invention provides modified TGF-.beta. family
proteins which comprise N-terminal extensions, truncations and
other modifications at the N-terminal end of C-terminal active
domains. Modified proteins of the invention have altered refolding
properties and altered solubility with respect to naturally
occurring proteins when expressed recombinantly. Modified proteins
of the invention also have altered activity profiles, including
enhanced specific activity, and are amenable to tissue-specific
targeting or specific surface binding.
[0019] As a result of these discoveries, means are available for
predicting and designing de novo BMPs and other TGF-.beta. family
member analogs having altered biological properties, including
improved folding capabilities in vitro, improved solubility,
altered stability, altered isoelectric points, and/or altered
biological activities, as desired. These discoveries also lend
themselves to creating proteins whose activity can be directed
towards specific sites within a mammal and/or whose activity can be
regulated, inhibited and/or induced. The invention also provides
means for easily and quickly evaluating biological and/or
biochemical properties of candidate constructs, including mapping
epitopes of folded proteins.
[0020] The invention provides "mutant" forms of proteins that
improve the refolding properties of "poor refolder" TGF-.beta.
family members. As used herein, a "poor refolder" protein means any
protein that, when induced to refold under suitable refolding
conditions, yields less than about 1% properly refolded material,
as measured using a standard protocol (see below). As contemplated
herein, "suitable refolding conditions" are conditions under which
proteins can be refolded to the extent required to confer
functionality. One skilled in the art will recognize that at least
Section IC and Example 3 of the "Detailed Description of the
Preferred Embodiment" are non-limiting examples of such refolding
conditions. Structural parameters relevant to the compositions and
methods of the instant invention include one or more disulfide
bridges properly distributed throughout the dimeric protein's
structure and which require a reduction-oxidation ("redox")
reaction step to yield a folded structure. Redox reactions
typically occur at neutral pH, i.e., in the range of about pH
7.0-8.5, typically in the range of about pH 7.5-8.5, and preferably
under physiologically-compatible conditions. The skilled artisan
will appreciate and recognize optimal conditions for success.
[0021] The proteins preferably are manufactured in accordance with
the principles disclosed herein by assembly of nucleotides and/or
joining DNA restriction fragments to produce synthetic DNAs. The
DNAs are transfected into an appropriate protein expression
vehicle, the encoded protein expressed, folded if necessary, and
purified. Particular constructs can be tested for activity in
vitro. The tertiary structure of the candidate protein constructs
may be iteratively refined and binding modulated by site-directed
or nucleotide sequence directed mutagenesis aided by the principles
disclosed herein, computer-based protein structure modeling, and
recently developed rational drug design techniques to improve or
modulate specific properties of a molecule of interest. Known phage
display or other nucleotide expression systems may be exploited to
produce simultaneously a large number of candidate constructs. The
pool of candidate constructs subsequently may be screened for
binding specificity using, for example, a chromatography column
comprising surface immobilized receptors, salt gradient elution to
select for, and to concentrate high binding candidates, and in
vitro assays. Identification of a useful recombinant protein is
followed by production of cell lines expressing commercially useful
quantities of the protein for laboratory use and ultimately for
producing therapeutically useful drugs. It has now been discovered
how to design, make, test and use chimeric proteins comprising an
amino acid sequence which, when properly folded, assume a tertiary
structure defining a finger 1 region, a finger 2 region, and a heel
region.
[0022] All of the constructs of the invention comprise regions of
amino acid sequences defining the regions required for utility,
namely, finger 1, finger 2, and heel regions, and an additional
region that can modify activity, namely the N-terminal peptide
sequence. Sequences for the finger and heel regions may be copied
from the respective finger and heel region sequences of any known
TGF-.beta. superfamily member identified herein. Alternatively, the
finger and heel regions may be selected from the amino acid
sequence of a new member of this superfamily discovered hereafter
using the principles disclosed hereinbelow.
[0023] The finger and heel sequences also may be altered by amino
acid substitution, for example by exploiting substitute amino acid
residues selected in accordance with the principles disclosed in
Smith et al. (1990) Proc. Natl. Acad. Sci. USA 87: 118-122, the
disclosure of which is incorporated herein by reference. Smith et
al. disclose an amino acid class hierarchy, similar to the amino
acid hierarchy table set forth in FIG. 3, which may be used to
rationally substitute one amino acid for another while minimizing
gross conformational distortions of the type which otherwise may
inactivate the protein. In any event, it is contemplated that many
synthetic finger 1, finger 2, and heel region sequences, having
only 70% homology with natural regions, preferably 80%, and most
preferably at least 90%, may be used to produce active morphon
constructs. It is contemplated also, as disclosed herein, that the
size of the constructs may be reduced significantly by truncating
the natural finger and heel regions of the template TGF-.beta.
superfamily member.
[0024] As used herein, "acidic" or "negatively charged residues"
are understood to include any amino acid residue,
naturally-occurring or synthetic, that typically carries a negative
charge on its R group under physiological conditions. Examples
include, without limitation, aspartic acid ("Asp") and glutamic
acid ("Glu"). Similarly, basic or positively charged residues
include any amino acid residue, naturally-occurring or
synthetically created, that typically carries a positive charge on
its R group under physiological conditions. Examples include,
without limitation, arginine ("Arg"), lysine ("Lys") and histidine
("His"). As used herein, "hydrophilic" residues include both acidic
and basic amino acid residues, as well as uncharged residues
carrying amide groups on their R groups, including, without
limitation, glutamine ("Gln") and asparagine ("Asn"), and polar
residues carrying hydroxyl groups on their R groups, including,
without limitation, serine ("Ser"), tyrosine ("Tyr") and threonine
("Thr"). A skilled artisan will appreciate that the actual
physiological pK will vary, and that the charge will vary in
different physiological environments.
[0025] As used herein, "biosynthesis" or "biosynthetic" means
occurring as a result of, or originating from a ligation of
naturally-or synthetically-derived fragments. For example, but not
limited to, ligating peptide or nucleic acid fragments
corresponding to one or more subdomains (or fragments thereof)
disclosed herein. "Chemosynthesis" or "chemosynthetic" means
occurring as a result of, or originating from, a chemical means of
production. For example, but not limited to, synthesis of a peptide
or nucleic acid sequence using a standard automated
synthesizer/sequencer from a commercially-available source. It is
contemplated that both natural and non-natural amino acids can be
used to obtain the desired attributes, as taught herein.
"Recombinant" production or technology means occurring as a result
of, or originating from, a genetically engineered means of
production. For example, but not limited to, expression of a
genetically-engineered DNA sequence or gene encoding a chimeric
protein (or fragment thereof) of the present invention. Also
included within the meaning of the foregoing are the teachings set
forth below in at least Sections I.B.; Section II; and at least
Examples 1 and 2. "Synthetic" means occurring or originating
non-naturally, i.e., not naturally occurring.
[0026] As used herein, "corresponding residue position" refers to a
residue position in a protein sequence that corresponds to a given
position in an OP-1 or other reference TGF-.beta. family member
amino acid sequence, when the two sequences are aligned. As will be
appreciated by those skilled in the art and as illustrated in FIG.
1, the sequences of BMP family members are highly conserved in the
C-terminal active domain, and particularly in the finger 2
sub-domain. Amino acid sequence alignment methods and programs are
well developed in the art. See, e.g., the method of Needleman, et
al. (1970) J. Mol. Biol. 48:443-453, implemented conveniently by
computer programs such as the Align program (DNAstar, Inc.).
Internal gaps and amino acid insertions in the second sequence are
ignored for purposes of calculating the alignment. For ease of
description, hOP-1 (human OP-1, also referred to in the art as
"BMP-7") is provided below as a representative osteogenic protein.
It will be appreciated however, that OP-1 is merely representative
of the TGF-.beta. family of proteins.
[0027] As used herein, "TGF-.beta. family member" or "TGF-.beta.
family protein," means a protein known to those of ordinary skill
in the art as a member of the TGF-.beta. superfamily. Structurally,
such proteins are disulfide-linked homo or heterodimers that are
expressed as large precursor polypeptide chains containing a
hydrophobic signal sequence, an N-terminal pro region of several
hundred amino acids, and a mature domain comprising a variable
N-terminal region and a more highly conserved C-terminal region
containing approximately 100 amino acids with a characteristic
cysteine motif having a conserved six or seven cysteine skeleton.
These structurally-related proteins have been identified as being
involved in a variety of developmental events. TGF-.beta. family
members are typified by TGF.beta.1 and OP-1. Other TGF-.beta.
family proteins useful in the practice of the present invention
include osteogenic proteins (as defined below), vg-1, DPP-C
polypeptide, the hormones activin and inhibin, MIS, VGR-1 and
growth/differentiation factors GDF-1, GDF-3, GDF-9 and
dorsalin-1.
[0028] It has been found that various members of the TGF-.beta.
protein superfamily mediate their activity by interaction with two
different cell surface receptors, referred to as Type I and Type II
receptors, to form a hetero-complex. The Type I and Type II
receptors are both serine/threonine kinases and share similar
structures: an intracellular domain that consists essentially of
the kinase, and a short, extended hydrophobic sequence sufficient
to span the membrane one time, and an extracellular ligand-binding
domain characterized by a high concentration of conserved
cysteines. The various Type I and Type II receptors have specific
binding affinity with OP-1 and other morphogenic proteins, and
their analogs, including the modified morphogens of the present
invention.
[0029] "Osteogenic protein", or "bone morphogenic protein," means a
TGF-.beta. superfamily protein which can induce the full cascade of
morphogenic events culminating in skeletal tissue formation,
including but not limited to cartilage and/or endochondral bone
formation. Osteogenic proteins useful herein include any known
naturally-occurring native proteins including allelic, phylogenetic
counterpart and other variants thereof, whether naturally-occurring
or biosynthetically produced (e.g., including "muteins" or "mutant
proteins"), as well as new, osteogenically active members of the
general morphogenic family of proteins. As described herein, this
class of proteins is generally typified by human osteogenic protein
1 (hOP-1). Other osteogenic proteins useful in the practice of the
invention include osteogenically active forms of proteins included
within the list of: OP-1, OP-2, OP-3, BMP-2, BMP-3, BMP-4, BMP-5,
BMP-6, BMP-9, DPP, Vg-1, Vgr, 60A protein, CDMP-1, CDMP-2, CDMP-3,
GDF-1, GDF-3, GDF-5, 6, 7, MP-52, BMP-10, BMP-11, BMP-12, BMP-13,
BMP-15, UNIVIN, NODAL, SCREW, ADMP or NEURAL, including amino acid
sequence variants thereof, and/or heterodimers thereof. In one
currently preferred embodiment, osteogenic protein useful in the
practice of the invention includes any one of: OP-1, BMP-2, BMP4,
BMP-12, BMP-13, GDF-5, GDF-6, GDF-7, CDMP-1, CDMP-2, CDMP-3, MP-52
and amino acid sequence variants and homologs thereof, including
species homologs thereof. In still another preferred embodiment,
useful osteogenically active proteins have polypeptide chains with
amino acid sequences comprising a sequence encoded by a nucleic
acid that hybridizes, under low, medium or high stringency
hybridization conditions, to DNA or RNA encoding reference
osteogenic sequences, e.g., C-terminal sequences defining the
conserved seven cysteine domains of OP-1, OP-2, BMP-2, BMP-4,
BMP-5, BMP-6, 60A, GDF-5, GDF-6, GDF-7 and the like. As used
herein, high stringent hybridization conditions are defined as
hybridization according to known techniques in 40% formamide,
5.times.SSPE, 5.times. Denhardt's Solution, and 0.1% SDS at
37.degree. C. overnight, and washing in 0.1.times.SSPE, 0.1% SDS at
50.degree. C. Standard stringency conditions are well characterized
in commercially available, standard molecular cloning texts. See,
for example, Molecular Cloning A Laboratory Manual, 2nd Ed., ed. by
Sambrook, Fritsch and Maniatis (Cold Spring Harbor Laboratory
Press: 1989); DNA Cloning, Volumes I and II (D. N. Glover ed.,
1985); Oligonucleotide Synthesis (M. J. Gait ed., 1984): Nucleic
Acid Hybridization (B. D. Hames & S. J. Higgins eds. 1984); and
B. Perbal, A Practical Guide To Molecular Cloning (1984); the
disclosures of the foregoing are incorporated by reference herein.
See also, U.S. Pat. Nos. 5,750,651 and 5,863,758, the disclosures
of which are incorporated by reference herein.
[0030] Other members of the TGF-.beta. superfamily of related
proteins having utility in the practice of the instant invention
include native poor refolder proteins among the list: TGF-.beta.1,
TGF-.beta.2, TGF-.beta.3, TGF-.beta.4 and TGF-.beta.5, various
inhibins, activins, BMP-11, and MIS, to name a few. FIG. 4 lists
the C-terminal 35 residues defining the finger 2 subdomain of
various known members of the TGF-.beta. superfamily. Any one of the
proteins on the list that is a poor refolder can be improved by the
methods of the invention, as can other known or discoverable family
members. As further described herein, the biologically active
osteogenic proteins suitable for use with the present invention can
be identified by means of routine experimentation using the
art-recognized bioassay described by Reddi and Sampath. A detailed
description of useful proteins follows. Equivalents can be
identified by the artisan using no more than routine
experimentation and ordinary skill.
[0031] "Morphogens" or "morphogenic proteins" as contemplated
herein includes members of the TGF-.beta. superfamily which have
been recognized to be morphogenic, i.e., capable of inducing the
developmental cascade of tissue morphogenesis in a mature mammal
(See PCT Application No. US 92/01968). In particular, these
morphogens are capable of inducing the proliferation of uncommitted
progenitor cells, and inducing the differentiation of these
stimulated progenitor cells in a tissue-specific manner under
appropriate environmental conditions. In addition, the morphogens
are capable of supporting the growth and maintenance of these
differentiated cells. These morphogenic activities allow the
proteins to initiate and maintain the developmental cascade of
tissue morphogenesis in an appropriate, morphogenically permissive
environment, stimulating stem cells to proliferate and
differentiate in a tissue-specific manner, and inducing the
progression of events that culminate in new tissue formation. These
morphogenic activities also allow the proteins to induce the
"redifferentiation" of cells previously stimulated to stray from
their differentiation path. Under appropriate environmental
conditions it is anticipated that these morphogens also may
stimulate the "redifferentiation" of committed cells. To guide the
skilled artisan, described herein are numerous means for testing
morphogenic proteins in a variety of tissues and for a variety of
attributes typical of morphogenic proteins. It will be understood
that these teachings can be used to assess morphogenic attributes
of native proteins as well as modified proteins of the present
invention.
[0032] Useful native or parent proteins of the present invention
also include those sharing at least 70% amino acid sequence
homology within the C-terminal seven-cysteine domain of human OP-1.
To determine the percent homology of a candidate amino acid
sequence to the conserved seven-cysteine domain, the candidate
sequence and the seven cysteine domain are aligned. The first step
for performing an alignment is to use an alignment tool, such as
the dynamic programming algorithm described in Needleman et al., J.
MOL. BIOL. 48: 443 (1970); the teachings of which are incorporated
by reference herein and the Align Program, a commercial software
package produced by DNAstar, Inc. After the initial alignment is
made, it is then refined by comparison to a multiple sequence
alignment of a family of related proteins. Once the alignment
between the candidate sequence and the seven-cysteine domain is
made and refined, a percent homology score is calculated. The
individual amino acids of each sequence are compared sequentially
according to their similarity to each other. Similarity factors
include similar size, shape and electrical charge. One particularly
preferred method of determining amino acid similarities is the
PAM250 matrix described in Dayhoff et al., 5 ATLAS OF PROTEIN
SEQUENCE AND STRUCTURE 345-352 (1978 & Supp.), incorporated by
reference herein. A similarity score is first calculated as the sum
of the aligned pairwise amino acid similarity scores. Insertions
and deletions are ignored for the purposes of percent homology and
identity. Accordingly, gap penalties are not used in this
calculation. The raw score is then normalized by dividing it by the
geometric mean of the scores of the candidate compound and the
seven cysteine domain. The geometric mean is the square root of the
product of these scores. The normalized raw score is the percent
homology.
[0033] As used herein, "conservative substitutions" are residues
that are physically or functionally similar to the corresponding
reference residues, e.g., that have similar size, shape, electric
charge, chemical properties including the ability to form covalent
or hydrogen bonds, or the like. Particularly preferred conservative
substitutions are those fulfilling the criteria defined for an
accepted point mutation in Dayhoff et al. Ibid. Examples of
conservative substitutions include the substitution of one amino
acid for another with similar characteristics, e.g., substitutions
within the following groups are well-known: (a) glycine, alanine;
(b) valine, isoleucine, leucine; (c) aspartic acid, glutamic acid;
(d) asparagine, glutamine; (e) serine, threonine; (f) lysine,
arginine, histidine; and (g) phenylalanine, tyrosine. The term
"conservative variant" or "conservative variation" also includes
the use of a substituted amino acid in place of an unsubstituted
parent amino acid in a given polypeptide chain, provided that
antibodies having binding specificity for the resulting substituted
polypeptide chain also have binding specificity (i.e., "crossreact"
or "immunoreact" with) the unsubstituted or parent polypeptide
chain.
[0034] As used herein, a "conserved residue position" refers to a
location in a reference amino acid sequence occupied by the same
amino acid or a conservative variant thereof in at least one other
member sequence. For example, in FIG. 4, comparing BMP-2, BMP-4,
BMP-5, and BMP-6 with OP-1 as the reference sequence, positions 1,
5, 9, 12, 14, 15, 16, 17, 19, 22, etc. are conserved positions, and
residues 2, 3, 4, 6, 7, 8, 10, 11, 13, 18, 20, 21, etc. are
non-conserved positions.
[0035] As used herein, the "base" or "neck" region of the finger 2
sub-domain is defined by residues 1-10 and 22-35, as exemplified by
OP-1, and counting from the first residue following the cysteine
doublet in the C-terminal active domain. (See FIG. 4). As is
readily apparent from a sequence alignment of other TGF-.beta.
protein family members with OP-1, the corresponding base or neck
region for a longer protein, such as BMP-9 or Dorsalin, is defined
by residues 1-10 and 23-36; for a shorter protein, such as NODAL,
the corresponding region is defined by residues 1-10 and 22-34 (See
FIG. 4). In SEQ ID NO: 39, (human OP-1), the residues corresponding
to the base or neck region of the finger 2 subdomain are residues
397-406 (corresponding to residues 1-10 in FIG. 4) and residues
418-431 (corresponding to residues 22-35 in FIG. 4).
[0036] As used herein, "C-terminal active domain" refers to the
conserved C-terminal region of mature TGF-.beta. family proteins.
The C-terminal active domain contains approximately 100 amino acids
with a characteristic cysteine motif having a six or seven cysteine
skeleton. The cysteine pattern of the C-terminus of all of the
proteins is in the identical format ending in the sequence
Cys-X-Cys-X (Sporn and Roberts (1990), supra.)
[0037] As used herein, "amino acid sequence homology" includes both
amino acid sequence identity and similarity. Homologous sequences
share identical and/or similar amino acid residues, where similar
residues are conservative substitutions for, or "allowed point
mutations" of, corresponding amino acid residues in an aligned
reference sequence.
[0038] As used herein, the terms "chimeric protein", "chimera",
"chimeric polypeptide chain", "chimeric construct" and "chimeric
mutant" refer to any BMP or TGF-.beta. family member synthetic
construct wherein the amino acid sequence of at least one defined
region, domain or sub-domain, such as the finger 1, finger 2 or
heel sub-domain, has been replaced in whole or in part with an
amino acid sequence from at least one other, different BMP or
TGF-.beta. family member protein, such that the resulting construct
has an amino acid sequence recognizable as being derived from the
different protein sources. Chimeric constructs also comprise
recombinant fusion proteins in which the C-terminal active domain
of one morphogen is fused to the N-terminal domain of another
morphogen.
[0039] As used herein, a "leader sequence" is any sequence of amino
acids corresponding to a sequence of nucleotides upstream, that is,
positioned farther to the C-terminal end, of the C-terminal active
domain region of a TGF-.beta. family protein. Modifications in the
leader sequence can alter refolding properties, activity levels,
solubility, control activation, and promote tissue-targeting as
well as affinity-binding ability.
[0040] As used herein, useful expression host cells include
prokaryotes and eukaryotes, including any host cell capable of
making an inclusion body. Particularly useful host cells include,
without limitation, bacterial hosts such as E. coli, as well as B.
subtilis and Pseudomonas. Other useful hosts include lower
eukaryotes, such as Saccharomyces cereviceae or other yeast, and
higher eukaryotes, such as Drosophila, CHO cells, and other
mammalian cells, and the like. As discussed herein, chemical
synthesis methods can also be utilized to generate the modified
proteins of the present invention.
[0041] In one aspect, the invention provides construction of
recombinant proteins not readily expressed in mammalian cells, such
as, for example, fusion proteins and the like. For example, a
recombinant gene encoding a fusion protein having bone targeting
properties is constructed, wherein a single sequence encodes both a
BMP and an antibody binding site having specificity for a bone
matrix protein such as osteocalcin or fibronectin. Similarly, a
fusion protein can also be constructed to bind to cell surface
receptors such as those on osteoprogenitor cells or chondrocytes.
Other recombinant genes may encode for fusion proteins that
specifically bind metals or other proteins. The specificity of the
binding would depend on the composition of the leader sequence that
is added to the BMP. These genes can be expressed in E. coli and
refolded in vitro.
[0042] In another embodiment, a cleavable fusion construct
(cleavable by proteases--such as trypsin, V8, factor Xa and others,
or chemically--with mild acid, hydroxylamine and other agents) is
synthesized wherein the TGF-.beta. protein is attached to a leader
sequence that blocks activity. In still another embodiment the
activity of a TGF-.beta. family member is restored or enhanced by
cleaving a portion or all of the leader sequence. By adding a
cleavable leader sequence that inhibits activity, a latent form of
the protein is created that can subsequently be cleaved to release
a protein fragment comprising the active C-terminal domain.
[0043] In yet another embodiment, the leader sequence is also a
tissue-targeting sequence, such that release can be controlled to
occur at the target site in vivo. The construction of the cleavage
site can also allow one to control the release of active protein.
For example, in bone tissue a number of proteases involved in bone
remodeling typically are present and can be used to advantage. A
cleavable "hexa-his", FB leader, or collagen binding sequence
described below may be a suitable leader sequence for a latent form
of the protein. By way of example, the tissue-targeting domain can
be separated from a BMP by a leader sequence that includes a run of
at least three basic residues, which is known to be cleaved in
vivo.
[0044] In still another embodiment, the leader sequence can be
constructed so that the portion of the protein that is inhibiting
specific activity is cleaved and activity restored, but the
tissue-targeting portion of the protein is retained.
[0045] In yet another preferred embodiment, the leader sequence of
the TGF-.beta. family protein is replaced by a leader sequence of
another TGF-.beta. member. The resultant "chimeric" protein may
have altered solubility, folding and/or tissue targeting activity,
improved stability, and/or the ability to bind to specific
surfaces.
[0046] In another aspect of the invention, the fusion proteins are
combined with other TGF-.beta. family proteins to form
heterodimers, wherein one can exploit the properties of each
protein. For example, a fusion protein with tissue-targeting
properties but no activity forms a heterodimer with a different
protein which has activity, but no tissue-targeting ability. The
former protein delivers the heterodimer to a target site where the
latter protein can perform its function.
[0047] In one aspect the invention provides biosynthetic BMPs and
TGF-.beta. family member proteins having improved refolding
properties under neutral or physiological conditions. In one
embodiment, the biosynthetic proteins of the invention have
improved refolding properties at a pH in the range of about
5.0-10.0, preferably in the range of about 6.0-9.0, more preferably
in the range of about 6.0-8.5, including in the range of about pH
7.0-7.5.
[0048] In another aspect the invention provides biosynthetic BMPs
and TGF-.beta. family member proteins having improved solubility
properties under neutral or physiological conditions. In one
embodiment, the biosynthetic proteins of the invention have
improved solubility at a pH in the range of about 5.0-10.0,
preferably in the range of about 6.0-9.0, more preferably in the
range of about 6.0-8.5, including in the range of about pH
7.0-7.5.
[0049] In still another aspect the invention provides biologically
active biosynthetic BMPs and TGF-.beta. family member constructs
competent to refold under physiological conditions and having
altered isoelectric points as compared with the parent
sequence.
[0050] In another aspect, the invention provides a method for
folding homodimers and heterodimers, which are poor refolders,
under physiological or neutral pH conditions. In one embodiment,
the method comprises the steps of providing one or more solubilized
TGF-.beta. family protein constructs of the invention, exposing the
solubilized protein to a redox reaction in a suitable refolding
buffer, and allowing the protein subunits to refold into homodimers
and/or heterodimers, as desired. In another embodiment, the
modified TGF-.beta. family proteins of the invention are not
denatured prior to exposing them to the redox reaction. In another
embodiment, the redox reaction system can utilize oxidized and
reduced forms of glutathione, DTT, .beta.-mercaptomethanol,
cysteine and cystamine. In another embodiment, the redox reaction
system relies on air oxidation, preferably in the presence of a
metal catalyst, such as copper. In still another embodiment, these
can be used as redox systems at ratios of reductant to oxidant of
about 1:10 to about 10:1, preferably in the range of about 1:2 to
2:1. In another preferred embodiment, the protein is solubilized in
the presence of a detergent, including an ionic detergent, a
non-ionic detergent, e.g. digitonin, or zwitterionic detergents,
such as 3-[(3cholamidopropyl)dimethylammonio]-1-- propanesulfate
(CHAPS), or N-octyl glucoside. In still another embodiment, the
refolding reaction occurs in a pH range of about 5.0-10.0,
preferably in the range of about 6.0-9.0, more preferably in the
range of about 7.0-8.5. In still another embodiment, the refolding
reaction occurs at a temperature within the range of about
32-0.degree. C., preferably in the range of about 25-4.degree. C.
Where heterodimers are being created, optimal ratios for adding the
two different subunits readily can be determined empirically and
without undue experimentation.
[0051] In another aspect, the invention provides methods for
recombinantly producing poor refolder BMP and other TGF-.beta.
family member proteins in a host cell, including a bacterial host,
or any other host cell where overexpressed protein aggregates in a
form that requires solubilization and/or refolding in vitro. The
method comprises the steps of providing a host cell transfected
with nucleic acid molecules encoding one or more of the
biosynthetic proteins of the invention, cultivating the host cells
under conditions suitable for expressing the biosynthetic protein,
collecting the aggregated protein, and solubilizing and refolding
the protein using the steps outlined above. In another embodiment,
the method comprises the additional step of transfecting the host
cell with a nucleic acid encoding the biosynthetic protein of the
invention.
[0052] Modified morphogens of the invention may be used to form
bone and/or cartilage in conjunction with a biocompatible matrix
such as (but not limited to) collagen, hydroxyapatite, ceramics,
carboxymethylcellulose, and/or other carrier suitable or matrix
material. Such combinations are particularly useful in methods for
regenerating bone, cartilage and/or other non-mineralized skeletal
or connective tissues such as (but not limited to) articular
cartilage, fibrocartilage, ligament, tendon, joint capsule,
menisci, intervertebral disks, synovial membrane tissue, muscle,
and fascia, to name but a few. See e.g. U.S. Pat. Nos. 5,674,292,
5,840,325 and U.S. application Ser. No. 08/235,398, the disclosures
of which are incorporated by reference herein. The present
invention contemplates that the binding and/or adherence properties
to such matrix materials can be altered using the techniques
disclosed herein for generating protein constructs. The modified
proteins of the invention may also be utilized to generate tendon,
ligament and/or muscle tissue.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] FIG. 1A is a simplified line drawing useful in describing
the structure of a monomeric subunit of a TGF-.beta. superfamily
member. See the Background of the Invention, supra, for
explanation. FIGS. 1B, 1C, and 1D are monovision ribbon tracings of
the respective peptide backbones of typical secondary structures of
the finger 1, heel, and finger 2 regions.
[0054] FIGS. 2A and 2B are stereo peptide backbone ribbon trace
drawings illustrating the generic three-dimensional shape of
TGF-.beta. superfamily member protein dimer: A) from the "top"
(down the two-fold axis of symmetry between the subunits) with the
axes of the helical heel regions generally normal to the paper and
the axes of each of the finger 1 and finger 2 regions generally
vertical, and B) from the "side" with the two-fold axis between the
subunits in the plane of the paper, with the axes of the heels
generally horizontal, and the axes of the fingers generally
vertical. The reader is encouraged to view the stereo alpha carbon
trace drawings in wall eyed stereo to understand better the spatial
relationships in the morphon design.
[0055] FIG. 3 is a pattern definition table prepared in accordance
with the teaching of Smith and Smith (1990) Proc. Natl. Acad. Sci.
USA 87:118-122.
[0056] FIG. 4 lists the aligned C-terminal residues defining the
finger 2 sub-domain for various known members of the BMP family,
and TGF-.beta. superfamily of proteins, starting with the first
residue following the cysteine doublet.
[0057] FIGS. 5A, 5B, and 5C are single letter code listings of
amino acid sequences, arranged to indicate alignments and
homologies of the finger 1, heel, and finger 2 regions,
respectively, of the currently known members of the TGF-.beta.
superfamily. Shown are the respective amino acids comprising each
region of human TGF-.beta.1 through TGF-.beta.5 (the TGF-.beta.
subgroup), the Vg/dpp subgroup consisting of dpp, Vg-1, Vgr-1, 60A
(see copending U.S. Ser. No. 08/271,556), BMP-2A (also known in the
literature as BMP-2), dorsalin, BMP-2B (also known in the
literature as BMP-4), BMP-3, BMP-5, BMP-6, OP-1 (also known in the
literature as BMP-7), OP-2 (see PCT/US91/07635 and U.S. Pat. No.
5,266,683) and OP-3 (U.S. Ser. No. 07/971,091), the GDF subgroup
consisting of GDF-1, GDF-3, and GDF-9, the Inhibin subgroup
consisting of Inhibin .alpha., Inhibin .beta.A, and Inhibin
.beta.B. The dashes (-) indicate a peptide bond between adjacent
amino acids. A consensus sequence pattern for each subgroup is
shown at the bottom of each subgroup.
[0058] FIG. 6 is a single letter code listing of amino acid
sequences, identified in capital letter in standard single letter
amino acid code, and in lower case letters to identify groups of
amino acids useful in that location, wherein the lower case letters
stand for the amino acids indicated in accordance with the pattern
definition key table set forth in FIG. 3. FIG. 6 identifies
preferred pattern sequences for constituting the finger 1, heel,
and finger 2 regions of biosynthetic constructs of the invention.
The dashes (-) indicate a peptide bond between adjacent amino
acids.
[0059] FIG. 7(A) shows the nucleotide and corresponding amino acid
sequences of H2487, a modified OP-1 comprising N-terminal
decapeptide collagen binding site inserted upstream of the
seven-cysteine domain.
[0060] FIG. 7(B) shows the nucleotide and corresponding amino acid
sequences of H2440, a modified OP-1 comprising a hexa-histidine
domain attached 35 residues upstream of the first cysteine in the
seven-cysteine domain.
[0061] FIG. 7(C) shows the nucleotide and amino acid sequences of
H2521, a modified OP-1 comprising an FB leader domain of protein A
attached 15 residues upstream of the first cysteine in the
seven-cysteine domain.
[0062] FIG. 7(D) shows the nucleotide and amino acid sequences of
H2525, a modified OP-1 comprising both an FB leader domain of
protein A and a hexa-histidine domain.
[0063] FIG. 7(E) shows the nucleotide and amino acid sequences of
H2527, a modified OP-1 comprising an FB leader domain, a
hexa-histidine domain, and an ASP-PRO acid cleavage site.
[0064] FIG. 7(F) shows the nucleotide and amino acid sequences of
H2528, a modified CDMP-3 comprising an FB leader domain and a
hexa-histidine domain.
[0065] FIG. 7(G) shows the nucleotide and amino acid sequences of
H2469, a modified OP-1 (truncated) comprising 14 original residues
upstream of the first cysteine in the conserved seven-cysteine
domain.
[0066] FIG. 7(H) shows the nucleotide and amino acid sequences of
H2510, a modified OP-1 comprising a collagen binding site inserted
7 residues upstream of the first cysteine in the conserved
seven-cysteine domain.
[0067] FIG. 7(I) shows the nucleotide and amino acid sequences of
H2523, a modified OP-1 comprising a collagen peptide and a spacer
added 13 residues upstream from the first cysteine in the conserved
seven-cysteine domain.
[0068] FIG. 7(J) shows the nucleotide and amino acid sequences of
H2524, a modified OP-1 comprising a hexa-histideine domain, a
collagen peptide and a spacer added 13 residues upstream from the
first cysteine in the conserved seven-cysteine domain.
[0069] FIG. 8 is a restriction map encoding the OP-1 C-terminal
seven cysteine active domain;
[0070] FIG. 9(A) is a schematic representation of various
biosynthetic chimeric BMP constructs;
[0071] FIG. 9(B) is a schematic representation of biosynthetic BMP
mutants and their refolding and ROS activity;
[0072] FIG. 10 shows the number of charged residues in the
C-terminal sub-domains for various BMPs.
[0073] FIG. 11 is a graph of ROS activity for OP-1 (standard), the
mutant H2549 protein and H2549 treated with trypsin, plotted as
concentration (ng/mL) vs. optical density (at 405 nm).
[0074] FIG. 12 is a graph of ROS activity for OP-1 (standard) and
various fractions of the mutant H2223 protein and the trypsin
truncated form of this protein, plotted as concentration (ng/mL)
vs. optical density (at 405 nm).
[0075] FIG. 13(A) is a graph of ROS activity for OP-1 homodimer
(from CHO cells), BMP-2 homodimer and hexa-his OP-1 heterodimer,
plotted as concentration (ng/mL) vs. optical density (405 nm).
[0076] FIG. 13(B) is a graph of ROS activity for OP-1 homodimer
(from CHO cells), hexa-his OP-1/BMP-2 heterodimer and hexa-his
OP-1, plotted as concentration (ng/mL) vs. optical density (405
nm).
[0077] FIG. 14 is a graph of ROS activity for OP-1 (standard),
BMP-2 mutant H2142 protein homodimer, mutant H2525 protein
homodimer and H2525/2142 heterodimer, plotted as concentration
(ng/mL) vs. optical density (405 nm).
[0078] FIG. 15 shows the amino acid sequences for the finger 2
subdomain of various OP-1 mutants and their folding efficiencies
and biological activities in the ROS cell based alkaline
phosphotase assay.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0079] The present invention provides modified forms of TGF-.beta.
family proteins which have altered refolding properties, and
altered activity profiles compared to natural forms. Modified
proteins of the invention comprise N-terminal modifications of
naturally-occurring TGF-.beta. family members, especially
morphogenic proteins. These modifications include extension,
truncation, and/or activation by protease or chemical cleavage at
specific sites (e.g., by acid or CNBr), attachment (fusion) of
distinct protein domains and production of heterodimers with
subunits from other TGF-.beta. family members. The detailed
description provided below describes an exemplary array of
substitutions, fusions, and extensions that result in improved
activity and pharmaceutical properties. Methods of producing
modified proteins are also taught.
[0080] According to one aspect of the invention, the folding
capabilities of poor refolder BMPs and other members of the
TGF-.beta. superfamily of proteins, including heterodimers and
chimeras thereof, are improved by fusing specific targeting and
receptor-binding regions to the existing N-terminal domain of BMP
or TGF-.beta. family members, which can then be cleaved at sites
within the fusion protein. As a result of this discovery, it is
possible to design BMP and other TGF-.beta. family proteins that
(1) are expressed recombinantly in prokaryotic or eukaryotic cells
or synthesized using polypeptide synthesizers; (2) have altered
folding capabilities; (3) have altered solubility under neutral
pHs, including but not limited to physiological conditions; (4)
have altered isoelectric points; (5) have altered stability; (6)
have altered binding or adherence properties to solid surfaces
(e.g., biocompatible matrices or metals); and/or (7) have a
desired, altered biological activity, such as tissue and/or
receptor specificity. In addition, the invention provides means for
testing new candidate constructs rapidly, particularly a biological
or biochemical property of the candidate. The invention also
provides means for rapidly mapping epitopes of antibodies, for
example by making chimeric proteins with different combinations of
domains. Specifically, making use of the discoveries disclosed
herein, morphogen sequences which otherwise could not be expressed
in a prokaryotic host such as E. coli now can be modified to allow
expression in E. coli and refolding in vitro.
[0081] Thus, the present invention can provide mechanisms for
designing quick-release, slow-release and/or timed-release
formulations containing a preferred chimeric protein. In addition,
the present invention provides mechanisms for designing
formulations engineered for environmentally-triggered release of a
protein construct. That is, modified proteins can be designed to
modulate delivery and facilitate release and activity under
particular environmental conditions in situ, such as changes in pH,
presence of a specific protease, etc. Other advantages and features
will be evident from the teachings below. Moreover, making use of
the discoveries disclosed herein, modified proteins having altered
surface-binding/surface-adherent properties can be designed and
selected. Surfaces of particular significance include, but are not
limited to, solid surfaces which can be naturally-occurring such as
bone; or porous particulate surfaces such as collagen or other
biocompatible matrices; or the fabricated surfaces of prosthetic
implants, including metals. As contemplated herein, virtually any
surface can be assayed for differential binding of constructs.
Thus, the present invention embraces a diversity of functional
molecules having alterations in their
surface-binding/surface-adherent properties, thereby rendering such
constructs useful for altered in vivo applications, including
slow-release, fast-release and/or timed-release formulations.
[0082] The skilled artisan will appreciate that mixing-and-matching
any one or more the above-recited attributes provides specific
opportunities to manipulate the uses of customized modified
proteins (and DNAs encoding the same). For example, the attribute
of altered stability can be exploited to manipulate the turnover of
a protein in vivo. Moreover, in the case of modified proteins also
having attributes such as altered re-folding and/or function, there
is likely an interconnection between folding, function and
stability. See, for example, Lipscomb et al., 7 Protein Sci. 765-73
(1998); and Nikolova et al., 95 Proc. Natl. Acad. Sci. USA 14675-80
(1998). For purposes of the present invention, stability
alterations can be routinely monitored using well-known techniques
of circular dichroism and other indices of stability as a function
of denaturant concentration or temperature. One can also use
routine scanning calorimetry. Similarly, there is likely an
interconnection between any of the foregoing attributes and the
attribute of solubility. In the case of solubility, it is possible
to manipulate this attribute so that a modified protein is either
more or less soluble under physiologically-compatible conditions
and it consequently diffuses readily or remains localized,
respectively, when administered in vivo.
[0083] Provided below are detailed descriptions of suitable
biosynthetic proteins and methods useful in the practice of the
invention, as well as methods for using and testing these proteins;
and numerous, nonlimiting examples which 1) illustrate the
suitability of the biosynthetic proteins and methods described
herein; and 2) provide assays with which to test and use these
proteins.
[0084] I. Protein Considerations
[0085] A. Structural Features TGF-.beta.2 and OP-1.
[0086] Each of the subunits in either TGF .beta.2 or OP-1 have a
characteristic folding pattern, illustrated schematically in FIG.
1A, that involves six of the seven C-terminal cysteine residues.
Briefly, four of the cysteine residues in each subunit form two
disulfide bonds which together create an eight residue ring, while
two additional cysteine residues form a disulfide bond that passes
through the ring to form a knot-like structure. With a numbering
scheme beginning with the most N-terminal cysteine of the 7
conserved cysteine residues assigned number 1, the 2nd and 6th
cysteine residues are disulfide bonded to close one side of the
eight residue ring while the 3rd and 7th cysteine residues are
disulfide bonded to close the other side of the ring. The 1st and
5th conserved cysteine residues are disulfide bonded through the
center of the ring to form the core of the knot. Amino acid
sequence alignment patterns suggest this structural motif is
conserved between members of the TGF-.beta. superfamily. The 4th
cysteine is semi-conserved and when present typically forms an
interchain disulfide bond (ICDB) with the corresponding cysteine
residue in the other subunit.
[0087] The structure of each subunit in TGF-.beta.2 and OP-1
comprise three major tertiary structural elements and an N-terminal
region. The structural elements are made up of regions of
contiguous polypeptide chain that possess over 50% secondary
structure of the following types: (1) loop, (2) .alpha.-helix and
(3) .beta.-sheet. Another defining criterion for each structural
region is that the entering (N-terminal) and exiting (C-terminal)
peptide strands are fairly close together, being about 7 A
apart.
[0088] The amino acid sequence between the 1st and 2nd conserved
cysteines, as shown in FIG. 1A, forms a structural region
characterized by an anti-parallel .beta.-sheet finger referred to
herein as the finger 1 region. Similarly the residues between the
5th and 6th conserved cysteines, as shown in FIG. 1A, also form an
anti-parallel .beta.-sheet finger, referred to herein as the finger
2 region. A .beta.-sheet finger is a single amino acid chain,
comprising a .beta.-strand that folds back on itself by means of a
.beta.-turn or some larger loop so that the polypeptide chain
entering and exiting the region form one or more anti-parallel
.beta.-sheet structures. The third major structural region,
involving the residues between the 3rd and 5th conserved cysteines,
as shown in FIG. 1A, is characterized by a three turn
.alpha.-helix, referred to herein as the heel region. The
organization of the monomer structure is similar to that of a left
hand where the knot region is located at the position equivalent to
the palm, the finger 1 region is equivalent to the index and middle
fingers, the .alpha.-helix, or heel region, is equivalent to the
heel of the hand, and the finger 2 region is equivalent to the ring
and small fingers. The N-terminal region, whose sequence is not
conserved across the TGF-.beta. superfamily, is predicted to be
located at a position roughly equivalent to the thumb.
[0089] Monovision ribbon tracings of the alpha carbon backbones of
each of the three major independent structural elements of the
TGF-.beta.2 monomer are illustrated in FIGS. 1B-1D. Specifically,
an exemplary finger 1 region comprising the first anti-parallel
.beta.-sheet segment is shown in FIG. 1B, an exemplary heel region
comprising the three turn .alpha.-helical segment is shown in FIG.
1C, and an exemplary finger 2 region comprising second and third
anti-parallel .beta.-sheet segments is shown in FIG. 1D.
[0090] FIG. 2 shows stereo ribbon trace drawings of the peptide
backbone of the conformationally active TGF-.beta.2 dimer complex.
The two monomer subunits in the dimer complex are oriented with
two-fold rotational symmetry such that the heel region of one
subunit contacts the finger regions of the other subunit with the
knot regions of the connected subunits forming the core of the
molecule. The 4th cysteine forms an interchain disulfide bond with
its counterpart on the second chain thereby equivalently linking
the chains at the center of the palms. The dimer thus formed is an
ellipsoidal (cigar shaped) molecule when viewed from the top
looking down the two-fold axis of symmetry between the subunits
(FIG. 2A). Viewed from the side, the molecule resembles a bent
"cigar" since the two subunits are oriented at a slight angle
relative to each other (FIG. 2B).
[0091] As shown in FIG. 2, each of the structural elements which
together define the native monomer subunits of the dimer are
labeled 22, 22', 23, 23', 24, 24', 25, 25', 26, and 26', wherein,
elements 22, 23, 24, 25, and 26 are defined by one subunit and
elements 22', 23', 24', 25', and 26' belong to the other subunit.
Specifically, 22 and 22' denote N-terminal domains; 23 and 23'
denote the finger 1 regions; 24 and 24' denote heel regions; 25 and
25' denote the finger 2 regions; and 26 and 26' denote disulfide
bonds which connect the 1st and 5th conserved cysteines of each
subunit to form the knot-like structure. From FIG. 2, it can be
seen that the heel region from one subunit, e.g., 24, and the
finger 1 and finger 2 regions, e.g., 23' and 25', respectively from
the other subunit, interact with one another. These three elements
co-operate with one other to define a structure interactive with,
and complimentary to the ligand binding interactive surface of the
cognate receptor.
[0092] (1) Selection of Finger and Heel Regions
[0093] It is contemplated that the amino acid sequences defining
the finger and heel regions may be utilized from the respective
finger and heel region sequences of any known member of the
TGF-.beta. superfamily, identified herein, or from amino acid
sequences of a new superfamily member discovered hereafter.
[0094] FIG. 5 summarizes the amino acid sequences of currently
identified TGF-.beta. superfamily members aligned into finger 1
(FIG. 5A), heel (FIG. 5B) and finger 2 (FIG. 5C) regions. The
sequences were aligned by a computer algorithm which in order to
optimally align the sequences inserted gaps into regions of amino
acid sequence known to define loop structures rather than regions
of amino acid sequence known to have conserved amino acid sequence
or secondary structure. For example, if possible, no gaps were
introduced into amino acid sequences of finger 1 and finger 2
regions defined by .beta. sheet or heel regions defined by a helix.
The dashes (-) indicate a peptide bond between adjacent amino
acids. A consensus sequence pattern for each subgroup is shown at
the bottom of each subgroup.
[0095] After the amino acid sequences of each of the TGF-.beta.
superfamily members were aligned, the aligned sequences were used
to produce amino acid sequence alignment patterns which identify
amino acid residues that may be substituted by another amino acid
or group of amino acids without altering the overall tertiary
structure of the resulting construct. The amino acids or groups of
amino acids that may be useful at a particular position in the
finger and heel regions were identified by a computer algorithm
implementing the amino acid hierarchy pattern structure shown in
FIG. 3.
[0096] Briefly, the algorithm performs four levels of analysis. In
level I, the algorithm determines whether a particular amino acid
residue occurs with a frequency greater than 75% at a specific
position within the amino acid sequence. For example, if a glycine
residue occurs 8 out of 10 times at a particular position in an
amino acid sequence, then a glycine is designated at that position.
If the position to be tested consists of all gaps then a gap
character (-) is assigned to the position, otherwise, if at least
one gap exists then a "z" (standing for any residue or a gap) is
assigned to the position. If, no amino acid occurs in 75% of the
candidate sequences at a particular position the algorithm
implements the Level II analysis.
[0097] Level II defines pattern sets a, b, d, l, k, o, n, i, and h,
wherein l, k, and o share a common amino acid residue. The
algorithm then determines whether 75% or more of the amino acid
residues at a particular position in the amino acid sequence
satisfy one of the aforementioned patterns. If so, then the pattern
is assigned to that position. It is possible, however, that both
patterns l and k may be simultaneously satisfied because they share
the same amino acid, specifically aspartic acid. If simultaneous
assignment of l and k occurs then pattern m (Level III) is assigned
to that position. Likewise, it is possible that both patterns k and
o may be simultaneously assigned because they share the same amino
acid, specifically glutamic acid. If simultaneous assignment of k
and o occurs, then pattern q (Level III) is assigned to that
position. If neither a Level II pattern nor the Level III patterns,
m and q, satisfy a particular position in the amino acid sequence
then the algorithm implements a Level III analysis.
[0098] Level III defines pattern sets c, e, m, q, p, and j, wherein
m, q, and p share a common amino residue. Pattern q, however, is
not tested in the Level III analysis. It is possible that both
patterns m and p may be simultaneously satisfied because they share
the same amino acid, specifically, glutamic acid. If simultaneous
assignment of m and p occurs then pattern r (Level IV) is assigned
to that position. If 75% of the amino acids at a pre-selected
position in the aligned amino acid sequences satisfy a Level III
pattern, then the Level III pattern is assigned to that position.
If a Level III pattern cannot be assigned to that position then the
algorithm implements a Level IV analysis.
[0099] Level IV comprises two non-overlapping patterns f and r. If
75% of the amino acids at a particular position in the amino acid
sequence satisfy a Level IV pattern then the pattern is assigned to
the position. If no Level IV pattern is assigned the algorithm
assigns an X representing any amino acid (Level V) to that
position.
[0100] In FIG. 3, Level I lists in upper case letters in single
amino acid code the 20 naturally occurring amino acids. Levels II-V
define, in lower case letters, groups of amino acids based upon the
amino acid hierarchy set forth in Smith et al., supra. The amino
acid sequences set forth in FIGS. 5 and 6 were aligned using the
aforementioned computer algorithms.
[0101] It is contemplated that if the artisan wishes to produce a
morphon construct based upon currently identified members of the
TGF-.beta. superfamily, then the artisan may use the amino acid
sequences shown in FIG. 5 to provide the finger 1, finger 2 and
heel regions useful in the production of the morphon constructs of
the invention. In the case of members of the TGF-.beta. superfamily
discovered hereafter, the amino acid sequence of the new member may
be aligned, either manually or by means of a computer algorithm,
with the sequences set forth in FIG. 5 to define heel and finger
regions useful in the practice of the invention.
[0102] Table 1 below summarizes publications which describe the
amino acid sequences of each TGF-.beta. superfamily member that
were used to produce the sequence alignment patterns set forth in
FIGS. 5 and 6.
1TABLE 1 TGF-.beta. Superfamily Member SEQ. ID. No. Publication
TGF-.beta.1 40 Derynck et al. (1987) Nucl. Acids. Res. 15: 3187
TGF-.beta.2 41 Burt et al. (1991) DNA Cell Biol. 10: 723-734
TGF-.beta.3 42 Ten Dijke et al. (1988) Proc. Natl. Acad. Sci. USA
85: 4715-4719; Derynck et al. (1988) EMBO J. 7: 3737-3743.
TGF-.beta.4 43 Burt et al. (1992) Mol. Endcrinol. 6: 989-922.
TGF-.beta.5 44 Kondaiah et al. (1990) J. Biol. Chem 265: 1089-1093
dpp 45 Padgett et al. (1987) Nature 325: 81-84; Paganiban et al.
(1990) Mol. Cell Biol. 10: 2669-2677. vg-1 46 Weeks et al. (1987)
Cell 51: 861-867 vgr-1 47 Lyons et al. (1989) Proc. Natl. Acad. Sci
USA 86: 4554-4558 60A 48 Wharton et al. (1991) Proc. Natl. Acad.
Sci. USA 88: 9214-9218; Doctor et al. (1992) Dev. Biol. 151:
491-505 BMP-2A 49 Wozney et al. (1988) Science 242: 1528-1534 BMP-3
50 Wozney et al. (1988) Science 242: 1528-1534 BMP-4 51 Wozney et
al. (1988) Science 242: 1528-1534 BMP-5 52 Celeste et al. (1990)
Proc. Natl. Acad. Sci. USA 87: 9843-9847 BMP-6 53 Celeste et al.
(1990) Proc. Natl. Acad. Sci. USA 87: 9843-9847 Dorsalin 54 Basler
et al. (1993) Cell 73: 687-702 OP-1 55 Celeste et al. (1990) Proc.
Natl. Acad. Sci. USA 87: 9843-9847; Ozkaynak et al. (1990) EMBO J.
9: 2085-2093 OP-2 56 Ozkaynak et al. (1992) J. Biol. Chem. 267:
25220-25227 OP-3 57 Ozkaynak et al. PCT/WO94/10203 Seq. I.D. No. 1.
GDF-1 58 Lee (1990) Mol. Endocrinol. 4: 1034-1040 GDF-3 59
McPherron et al. (1993) J. Biol. Chem. 268: 3444-3449 GDF-9 60
McPherron et al. (1993) J. Biol. Chem. 268: 3444-3449 Inhibin
.alpha. 61 Mayo et al. (1986) Proc. Natl. Acad. Sci. USA 83:
5849-5853; Stewart et al. (1986) FEBS Lett 206: 329-334; Mason et
al. (1986) Biochem. Biophys. Res. Commun. 135: 957-964 Inhibin
.beta.A 62 Forage et al. (1986) Proc. Natl. Acad. Sci. USA 83:
3091-3095; Chertov et al. (1990) Biomed. Sci. 1: 499-506 Inhibin
.beta.B 63 Mason et al. (1986) Biochem. Biophys. Res. Commun. 135:
957-964
[0103] The invention further contemplates the use of corresponding
finger 1 subdomain sequences from the well-known proteins: GDF-5,
GDF-7 (as disclosed in U.S. Pat. No. 5,801,014, the entire
disclosure of which is incorporated herein by reference); GDF-6 (as
disclosed in U.S. Pat. No. 5,770,444, the entire disclosure of
which is incorporated herein by reference); and BMP-12 and BMP-13
(as disclosed in U.S. Pat. No. 5,658,882, the entire disclosure of
which is incorporated herein by reference).
[0104] In particular, it is contemplated that amino acid sequences
defining finger 1 regions useful in the practice of the instant
invention correspond to the amino acid sequence defining a finger 1
region for any TGF-.beta. superfamily member identified herein. The
finger 1 subdomain can confer at least biological and/or functional
attribute(s) which are characteristic of the native protein. Useful
intact finger 1 regions include, but are not limited to
2 TGF-.beta.1 SEQ. ID. No. 40, residues 2 through 29, TGF-.beta.2
SEQ. ID. No. 41, residues 2 through 29, TGF-.beta.3 SEQ. ID. No.
42, residues 2 through 29, TGF-.beta.4 SEQ. ID. No. 43, residues 2
through 29, TGF-.beta.5 SEQ. ID. No. 44, residues 2 through 29, dpp
SEQ. ID. No. 45, residues 2 through 29, Vg-1 SEQ. ID. No. 46,
residues 2 through 29, Vgr-1 SEQ. ID. No. 47, residues 2 through
29, 60A SEQ. ID. No. 48, residues 2 through 29, BMP-2A SEQ. ID. No.
49, residues 2 through 29, BMP-3 SEQ. ID. No. 50, residues 2
through 29, BMP-4 SEQ. ID. No. 51, residues 2 through 29, BMP-5
SEQ. ID. No. 52, residues 2 through 29, BMP-6 SEQ. ID. No. 53,
residues 2 through 29, Dorsalin SEQ. ID. No. 54, residues 2 through
29, OP-1 SEQ. ID. No. 55, residues 2 through 29, OP-2 SEQ. ID. No.
56, residues 2 through 29, OP-3 SEQ. ID. No. 57, residues 2 through
29, GDF-1 SEQ. ID. No. 58, residues 2 through 29, GDF-3 SEQ. ID.
No. 59, residues 2 through 29, GDF-9 SEQ. ID. No. 60, residues 2
through 29, Inhibin .alpha. SEQ. ID. No. 61, residues 2 through 29,
Inhibin .beta.A SEQ. ID. No. 62, residues 2 through 29, Inhibin
.beta.B SEQ. ID. No. 63, residues 2 through 29, CDMP-1/GDF-5 SEQ.
ID. No. 83, residues 2 through 29, CDMP-2/GDF-6 SEQ. ID. No. 84,
residues 2 through 29, GDF-6 (murine) SEQ. ID. No. 85, residues 2
through 29, CDMP-2 (bovine) SEQ. ID. No. 86, residues 2 through 29,
and GDF-7 (murine) SEQ. ID. No. 87, residues 2 through 29.
[0105] The invention further contemplates the use of corresponding
heel subdomain sequences from the well-known proteins BMP-12 and
BMP-13 (as disclosed in U.S. Pat. No. 5,658,882, the entire
disclosure of which is incorporated herein by reference).
[0106] It is contemplated also that amino acid sequences defining
heel regions useful in the practice of the instant invention
correspond to the amino acid sequence defining an intact heel
region for any TGF-.beta. superfamily member identified herein. The
heel region can at least influence attributes of the native
protein, including functional and/or folding attributes. Useful
intact heel regions may include, but are not limited to
3 TGF-.beta.1 SEQ. ID. No. 40, residues 35 through 62, TGF-.beta.2
SEQ. ID. No. 41, residues 35 through 62, TGF-.beta.3 SEQ. ID. No.
42, residues 35 through 62, TGF-.beta.4 SEQ. ID. No. 43, residues
35 through 62, TGF-.beta.5 SEQ. ID. No. 44, residues 35 through 62,
dpp SEQ. ID. No. 45, residues 35 through 65, Vg-1 SEQ. ID. No. 46,
residues 35 through 65, Vgr-1 SEQ. ID. No. 47, residues 35 through
65, 60A SEQ. ID. No. 48, residues 35 through 65, BMP-2 SEQ. ID. No.
49, residues 35 through 64, BMP3 SEQ. ID. No. 50, residues 35
through 66, BMP-4 SEQ. ID. No. 51, residues 35 through 64, BMP-5
SEQ. ID. No. 52, residues 35 through 65, BMP-6 SEQ. ID. No. 53,
residues 35 through 65, Dorsalin SEQ. ID. No. 54, residues 35
through 65, OP-1 SEQ. ID. No. 55, residues 35 through 65, OP-2 SEQ.
ID. No. 56, residues 35 through 65, OP-3 SEQ. ID. No. 57, residues
35 through 65, GDF-1 SEQ. ID. No. 58, residues 35 through 70, GDF-3
SEQ. ID. No. 59, residues 35 through 64, GDF-9 SEQ. ID. No. 60,
residues 35 through 65, Inhibin .alpha. SEQ. ID. No. 61, residues
35 through 65, Inhibin .beta.A SEQ. ID. No. 62, residues 35 through
69, Inhibin .beta.B SEQ. ID. No. 63, residues 35 through 68,
CDMP-1/GDF-5 SEQ. ID. No. 83, residues 35 through 65, CDMP-2/GDF-6
SEQ. ID. No. 84, residues 35 through 65, GDF-6 (murine) SEQ. ID.
No. 85, residues 35 through 65, CDMP-2 (bovine) SEQ. ID. No. 86,
residues 35 through 65, and GDF-7 (murine) SEQ. ID. No. 87,
residues 35 through 65.
[0107] The invention further contemplates the use of corresponding
finger 2 subdomain sequences from the well-known proteins BMP-12
and BMP-13 (as disclosed in U.S. Pat. No. 5,658,882, the entire
disclosure of which is incorporated herein by reference).
[0108] It is contemplated also that amino acid sequences defining
finger 2 regions useful in the practice of the instant invention
correspond to the amino acid sequence defining an intact finger 2
region for any TGF-.beta. superfamily member identified herein. The
finger 2 subdomain can confer at least folding attribute(s) which
are characteristic of the native protein. Useful intact finger 2
regions may include, but are not limited to
4 TGF-.beta.1 SEQ. ID. No. 40, residues 65 through 94, TGF-.beta.2
SEQ. ID. No. 41, residues 65 through 94, TGF-.beta.3 SEQ. ID. No.
42, residues 65 through 94, TGF-.beta.4 SEQ. ID. No. 43, residues
65 through 94, TGF-.beta.5 SEQ. ID. No. 44, residues 65 through 94,
dpp SEQ. ID. No. 45, residues 68 through 98, Vg-1 SEQ. ID. No. 46,
residues 68 through 98, Vgr-1 SEQ. ID. No. 47, residues 68 through
98, 60A SEQ. ID. No. 48, residues 68 through 98, BMP-2A SEQ. ID.
No. 49, residues 67 through 97, BMP-3 SEQ. ID. No. 50, residues 69
through 99, BMP-4 SEQ. ID. No. 51, residues 67 through 97, BMP-5
SEQ. ID. No. 52, residues 68 through 98, BMP-6 SEQ. ID. No. 53,
residues 68 through 98, Dorsalin SEQ. ID. No. 54, residues 68
through 99, OP-1 SEQ. ID. No. 55, residues 68 through 98, OP-2 SEQ.
ID. No. 56, residues 68 through 98, OP-3 SEQ. ID. No. 57, residues
68 through 98, GDF-1 SEQ. ID. No. 58, residues 73 through 103,
GDF-3 SEQ. ID. No. 59, residues 67 through 97, GDF-9 SEQ. ID. No.
60, residues 68 through 98, Inhibin .alpha. SEQ. ID. No. 61,
residues 68 through 101, Inhibin .beta.A SEQ. ID. No. 62, residues
72 through 102, Inhibin .beta.B SEQ. ID. No. 63, residues 71
through 101, CDMP-1/GDF-5 SEQ. ID. No. 83, residues 68 through 98,
CDMP-2/GDF-6 SEQ. ID. No. 84, residues 68 through 98, GDF-6
(murine) SEQ. ID. No. 85, residues 68 through 98, CDMP-2 (bovine)
SEQ. ID. No. 86, residues 68 through 98, and GDF-7 (murine) SEQ.
ID. No. 87, residues 68 through 98.
[0109] In addition, it is contemplated that the amino acid
sequences of the respective finger and heel regions can be altered
by amino acid substitution, for example by exploiting substitute
residues as disclosed herein or selected in accordance with the
principles disclosed in Smith et al. (1990), supra. Briefly, Smith
et al. disclose an amino acid class hierarchy similar to the one
summarized in FIG. 3, which can be used to rationally substitute
one amino acid for another while minimizing gross conformational
distortions of the type which could compromise protein function. In
any event, it is contemplated that many synthetic first finger,
second finger, and heel region sequences, having only 70% homology
with natural regions, preferably 80%, and most preferably at least
90%, can be used to produce the constructs of the present
invention. Amino acid sequence patterns showing amino acids
preferred at each location in the finger and heel regions, deduced
in accordance with the principles described in Smith et al. (1990)
supra, also are show in FIGS. 5 and 6, and are referred to as the:
TGF-.beta.; Vg/dpp; GDF; and Inhibin subgroup patterns. The amino
acid sequences defining the finger 1, heel and finger 2 sequence
patterns of each subgroup are set forth in FIGS. 5A, 5B, and 5C,
respectively. In addition, the amino acid sequences defining the
entire TGF-.beta., Vg/dpp, GDF and Inhibin subgroup patterns are
set forth in the Sequence Listing as SEQ. ID. Nos. 64, 65, 66, and
67, respectively.
[0110] The preferred amino acid sequence patterns for each
subgroup, disclosed in FIGS. 5A, 5B, and 5C, and summarized in FIG.
6, enable one skilled in the art to identify alternative amino
acids that may be incorporated at specific positions in the finger
1, heel, and finger 2 elements. The amino acids identified in upper
case letters in a single letter amino acid code identify conserved
amino acids that together are believed to define structural and
functional elements of the finger and heel regions. The upper case
letter "X" in FIGS. 5 and 6 indicates that any naturally occurring
amino acid is acceptable at that position. The lower case letter
"z" in FIGS. 5 and 6 indicates that either a gap or any of the
naturally occurring amino acids is acceptable at that position. The
lower case letters stand for the amino acids indicated in
accordance with the pattern definition table set forth in FIG. 5
and identify groups of amino acids which are useful in that
location.
[0111] In accordance the amino acid sequence subgroup patterns set
forth in FIGS. 5 and 6, it is contemplated, for example, that the
skilled artisan may be able to predict that where applicable, one
amino acid may be substituted by another without inducing
disruptive stereochemical changes within the resulting protein
construct. For example, in FIG. 5A, in the TGF-.beta. subgroup
pattern at residue number 12 it is contemplated that either a
lysine residue (K) or a glutamine residue (Q) may be present at
this position without affecting the structure of the resulting
construct. Accordingly, the sequence pattern at position 12
contains an "n" which in accordance with FIG. 10 defines an amino
acid residue selected from the group consisting of lysine or
glutamine. It is contemplated, therefore, that many synthetic
finger 1, finger 2 and heel region amino acid sequences, having 70%
homology, preferably 80%, and most preferably at least 90% with the
natural regions, may be used to produce conformationally active
proteins of the invention.
[0112] In accordance with these principles, it is contemplated that
one may design a synthetic construct by starting with the amino
acid sequence patterns belonging to the TGF-.beta., Vg/dpp, GDF, or
Inhibin subgroup patterns shown in FIGS. 5 and 6. Thereafter, by
using conventional recombinant or synthetic methodologies a
preselected amino acid may be substituted by another as guided by
the principles herein and the resulting protein construct tested
for binding activity in combination with either agonist or
antagonist activity.
[0113] The TGF-.beta. subgroup pattern, SEQ. ID. No. 64,
accommodates the homologies shared among members of the TGF-.beta.
subgroup identified to date including TGF-.beta.1, TGF-.beta.2,
TGF-.beta.3, TGF-.beta.4, and TGF-.beta.5. The generic sequence,
shown below, includes both the conserved amino acids (standard
three letter code) as well as alternative amino acids (Xaa) present
at the variable positions within the sequence and defined by the
rules set forth in FIG. 3.
5 TGF-.beta. Subgroup Pattern Cys Cys Val Arg Pro Leu Tyr Ile Asp
Phe Arg Xaa Asp Leu Gly Trp 1 5 10 15 Lys Trp Ile His Glu Pro Lys
Gly Tyr Xaa Ala Asn Phe Cys Xaa Gly 20 25 30 Xaa Cys Pro Tyr Xaa
Trp Ser Xaa Asp Thr Gln Xaa Ser Xaa Val Leu 35 40 45 Xaa Leu Tyr
Asn Xaa Xaa Asn Pro Xaa Ala Ser Ala Xaa Pro Cys Cys 50 55 60 Val
Pro Gln Xaa Leu Glu Pro Leu Xaa Ile Xaa Tyr Tyr Val Gly Arg 65 70
75 80 Xaa Xaa Lys Val Glu Gln Leu Ser Asn Met Xaa Val Xaa Ser Cys
Lys 85 90 95 Cys Ser.
[0114] Each Xaa can be independently selected from a group of one
or more specified amino acids defined as follows, wherein: Xaa12 is
Arg or Lys; Xaa26 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His,
Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa31 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa33 is Ala, Gly, Pro, Ser,
or Thr; Xaa37 is Ile, Leu, Met or Val; Xaa40 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa44 is His, Phe, Trp or Tyr; Xaa46 is Arg or
Lys; Xaa49 is Ala, Gly, Pro, Ser, or Thr; Xaa53 is Arg, Asn, Asp,
Gln, Glu, His, Lys, Ser or Thr; Xaa54 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr or Val; Xaa57 is Ala, Arg, Asn, Asp, Cys, Glu, Gin, Gly, His,
Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa61 is
Ala, Gly, Pro, Ser, or Thr; Xaa68 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or
Val; Xaa73 is Ala, Gly, Pro, Ser, or Thr; Xaa75 is Ile, Leu, Met or
Val; Xaa81 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa82
is Ala, Gly, Pro, Ser, or Thr; Xaa91 is Ile or Val; Xaa93 is Arg or
Lys.
[0115] The Vg/dpp subgroup pattern, SEQ. ID. No. 65, accommodates
the homologies shared among members of the Vg/dpp subgroup
identified to date including dpp, vg-1, vgr-1, 60A, BMP-2A (BMP-2),
Dorsalin, BMP-2B (BMP-4), BMP-3, BMP-5, BMP-6, OP-1 (BMP-7), OP-2
and OP-3. The generic sequence, below, includes both the conserved
amino acids (standard three letter code) as well as alternative
amino acids (Xaa) present at the variable positions within the
sequence and defined by the rules set forth in FIG. 3.
6 Vg/dpp Subgroup Pattern Cys Xaa Xaa Xaa Xaa Leu Tyr Val Xaa Phe
Xaa Asp Xaa Gly Trp Xaa 1 5 10 15 Asp Trp Ile Ile Ala Pro Xaa Gly
Tyr Xaa Ala Xaa Tyr Cys Xaa Gly 20 25 30 Xaa Cys Xaa Phe Pro Leu
Xaa Xaa Xaa Xaa Asn Xaa Thr Asn His Ala 35 40 45 Ile Xaa Gln Thr
Leu Val Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Pro 50 55 60 Lys Xaa
Cys Cys Xaa Pro Thr Xaa Leu Xaa Ala Xaa Ser Xaa Leu Tyr 65 70 75 80
Xaa Asp Xaa Xaa Xaa Xaa Xaa Val Xaa Leu Xaa Xaa Tyr Xaa Xaa Met 85
90 95 Xaa Val Xaa Xaa Cys Gly Cys Xaa. 100
[0116] Each Xaa can be independently selected from a group of one
or more specified amino acids defined as follows, wherein: Xaa2 is
Arg or Lys; Xaa3 is Arg or Lys; Xaa4 is Arg, Asn, Asp, Gln, Glu,
His, Lys, Ser or Thr; Xaa5 is Arg, Asn, Asp, Gln, Glu, His, Lys,
Ser or Thr; Xaa9 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr;
Xaa11 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa13 is
Ile, Leu, Met or Val; Xaa16 is Arg, Asn, Asp, Gln, Glu, His, Lys,
Ser or Thr; Xaa23 is Arg, Gln, Glu, or Lys; Xaa26 is Ala, Arg, Asn,
Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser,
Thr, Trp, Tyr or Val; Xaa28 is Phe, Trp or Tyr; Xaa31 is Arg, Asn,
Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa33 is Asp or Glu; Xaa35 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa39 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa40 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa41
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa42 is Leu or Met; Xaa44 is
Ala, Gly, Pro, Ser, or Thr; Xaa50 is Ile or Val; Xaa55 is Arg, Asn,
Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa56 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa57 is Ile, Leu, Met or Val; Xaa58 is Arg, Asn,
Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa59 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr, Val or a peptide bond; Xaa60 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr, Val or a peptide bond; Xaa61 is Arg, Asn, Asp, Gln, Glu, His,
Lys, Ser or Thr; Xaa62 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa63
is Ile or Val; Xaa66 is Ala, Gly, Pro, Ser, or Thr; Xaa69 is Ala,
Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe,
Pro, Ser, Thr, Trp, Tyr or Val; Xaa72 is Arg, Gin, Glu, or Lys;
Xaa74 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa76 is
Ile or Val; Xaa78 is Ile, Leu, Met or Val; Xaa81 is Cys, Ile, Leu,
Met, Phe, Trp, Tyr or Val; Xaa83 is Asn, Asp or Glu; Xaa84 is Arg,
Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa85 is Ala, Arg, Asn,
Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser,
Thr, Trp, Tyr, Val or a peptide bond; Xaa86 is Arg, Asn, Asp, Gln,
Glu, His, Lys, Ser or Thr; Xaa87 is Arg, Asn, Asp, Gln, Glu, His,
Lys, Ser or Thr; Xaa89 is Ile or Val; Xaa91 is Arg or Lys; Xaa92 is
Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa94 is Arg, Gln,
Glu, or Lys; Xaa95 is Asn or Asp; Xaa97 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr or Val; Xaa99 is Arg, Gln, Glu, or Lys; Xaa100 is Ala, Gly,
Pro, Ser, or Thr; Xaa104 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser
or Thr.
[0117] The GDF subgroup pattern, SEQ. ID. No. 66, accommodates the
homologies shared among members of the GDF subgroup identified to
date including GDF-1, GDF-3, and GDF-9. The generic sequence, shown
below, includes both the conserved amino acids (standard three
letter code) as well as alternative amino acids (Xaa) present at
the variable positions within the sequence and defined by the rules
set forth in FIG. 3.
7 GDF Subgroup Pattern Cys Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Phe Xaa
Xaa Xaa Xaa Trp Xaa 1 5 10 15 Xaa Trp Xaa Xaa Ala Pro Xaa Xaa Xaa
Xaa Xaa Xaa Xaa Cys Xaa Gly 20 25 30 Xaa Cys Xaa Xaa Xaa Xaa Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa Xaa Xaa Xaa Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 55 60 Pro Xaa Xaa
Xaa Xaa Xaa Xaa Cys Val Pro Xaa Xaa Xaa Ser Pro Xaa 65 70 75 80 Ser
Xaa Leu Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Tyr 85 90
95 Glu Asp Met Xaa Xaa Xaa Xaa Cys Xaa Cys Xaa. 100 105
[0118] Each Xaa can be independently selected from a group of one
or more specified amino acids defined as follows, wherein: Xaa2 is
Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa3 is Ala, Arg,
Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro,
Ser, Thr, Trp, Tyr or Val; Xaa4 is Arg, Asn, Asp, Gln, Glu, His,
Lys, Ser or Thr; Xaa5 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or
Thr; Xaa6 is Cys, Ile, Leu, Met, Phe, Trp, Tyr or Val; Xaa7 is Ala,
Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe,
Pro, Ser, Thr, Trp, Tyr or Val; Xaa8 is Ile, Leu, Met or Val; Xaa9
is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa11 is Arg,
Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa12 is Arg, Asn, Asp,
Gln, Glu, His, Lys, Ser or Thr; Xaa13 is Ile, Leu, Met or Val;
Xaa14 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa16 is Arg, Asn,
Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa17 is Arg, Asn, Asp, Gln,
Glu, His, Lys, Ser or Thr; Xaa19 is Ile or Val; Xaa20 is Ile or
Val; Xaa23 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa24
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa25 is Phe, Trp or Tyr;
Xaa26 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa27 is Ala, Gly,
Pro, Ser, or Thr; Xaa28 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser
or Thr; Xaa29 is Phe, Trp or Tyr; Xaa31 is Arg, Asn, Asp, Gln, Glu,
His, Lys, Ser or Thr; Xaa33 is Arg, Asn, Asp, Gln, Glu, His, Lys,
Ser or Thr; Xaa35 is Ala, Gly, Pro, Ser, or Thr; Xaa36 is Ala, Arg,
Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro,
Ser, Thr, Trp, Tyr or Val; Xaa37 is Ala, Gly, Pro, Ser, or Thr;
Xaa38 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa39 is Arg, Asn,
Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa40 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa41 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa42
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa43 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr, Val or a peptide bond; Xaa44 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr, Val or a peptide bond; Xaa45 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr,
Val or a peptide bond; Xaa46 is Ala, Arg, Asn, Asp, Cys, Glu, Gln,
Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr, Val or
a peptide bond; Xaa47 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa48
is Ala, Gly, Pro, Ser, or Thr; Xaa49 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr or Val; Xaa50 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His,
Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa51 is
His, Phe, Trp or Tyr; Xaa52 is Ala, Gly, Pro, Ser, or Thr; Xaa53 is
Cys, Ile, Leu, Met, Phe, Trp, Tyr or Val; Xaa54 is Ile, Leu, Met or
Val; Xaa55 is Arg, Gln, Glu, or Lys; Xaa56 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa57 is Ile, Leu, Met or Val; Xaa58 is Ile, Leu,
Met or Val; Xaa59 is His, Phe, Trp or Tyr; Xaa60 is Ala, Arg, Asn,
Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser,
Thr, Trp, Tyr or Val; Xaa61 is Ala, Arg, Asn, Asp, Cys, Glu, Gln,
Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val;
Xaa62 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa63 is Ala, Arg,
Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro,
Ser, Thr, Trp, Tyr, Val or a peptide bond; Xaa64 is Ala, Arg, Asn,
Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser,
Thr, Trp, Tyr, Val or a peptide bond; Xaa66 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa67 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa68
is Ala, Gly, Pro, Ser, or Thr; Xaa69 is Arg, Asn, Asp, Gln, Glu,
His, Lys, Ser or Thr; Xaa70 is Ala, Gly, Pro, Ser, or Thr; Xaa71 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa75 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa76 is Arg or Lys; Xaa77 is Cys, Ile, Leu, Met,
Phe, Trp, Tyr or Val; Xaa80 is Ile, Leu, Met or Val; Xaa82 is Ile,
Leu, Met or Val; Xaa84 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa85
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa86 is Asp or Glu; Xaa87 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa88 is Arg, Asn, Asp, Gln,
Glu, His, Lys, Ser or Thr; Xaa89 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or
Val; Xaa90 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa91
is Ile or Val; Xaa92 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa93
is Cys, Ile, Leu, Met, Phe, Trp, Tyr or Val; Xaa94 is Arg or Lys;
Xaa95 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa100 is
Ile or Val; Xaa101 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His,
Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa102 is
Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa103 is Arg, Gln,
Glu, or Lys; Xaa105 is Ala, Gly, Pro, Ser, or Thr; Xaa107 is Ala,
Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe,
Pro, Ser, Thr, Trp, Tyr or Val.
[0119] The Inhibin subgroup pattern, SEQ. ID. No. 67, accommodates
the homologies shared among members of the Inhibin subgroup
identified to date including Inhibin .alpha., Inhibin .beta.A and
Inhibin .beta.B. The generic sequence, shown below, includes both
the conserved amino acids (standard three letter code) as well as
alternative amino acids (Xaa) present at the variable positions
within the sequence and defined by the rules set forth in FIG.
3.
8 Inhibin Subgroup pattern Cys Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Phe
Xaa Xaa Xaa Gly Trp Xaa 1 5 10 15 Xaa Trp Ile Xaa Xaa Pro Xaa Xaa
Xaa Xaa Xaa Xaa Tyr Cys Xaa Gly 20 25 30 Xaa Cys Xaa Xaa Xaa Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa Xaa Xaa Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 55 60 Xaa Xaa
Xaa Xaa Xaa Cys Cys Xaa Xaa Xaa Pro Xaa Xaa Xaa Xaa Xaa 65 70 75 80
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Asp Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 85
90 95 Xaa Xaa Xaa Asn Xaa Xaa Xaa Xaa Xaa Cys Xaa Cys Xaa. 100
105
[0120] Each Xaa can be independently selected from a group of one
or more specified amino acids defined as follows, wherein: Xaa2 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa3 is Arg or Lys; Xaa4 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa5 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa6 is Cys, Ile, Leu, Met, Phe, Trp, Tyr or Val;
Xaa7 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys,
Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa8 is Ile or Val; Xaa9
is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa11 is Arg,
Gln, Glu, or Lys; Xaa12 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa13
is Ile, Leu, Met or Val; Xaa16 is Asn, Asp or Glu; Xaa17 is Arg,
Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa20 is Ile or Val;
Xaa21 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa23 is Ala, Gly,
Pro, Ser, or Thr; Xaa24 is Ala, Gly, Pro, Ser, or Thr; Xaa25 is
Phe, Trp or Tyr; Xaa26 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa27
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa28 is Arg, Asn, Asp, Gln,
Glu, His, Lys, Ser or Thr; Xaa31 is Arg, Asn, Asp, Gln, Glu, His,
Lys, Ser or Thr; Xaa33 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa35
is Ala, Gly, Pro, Ser, or Thr; Xaa36 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr or Val; Xaa37 is His, Phe, Trp or Tyr; Xaa38 is Ile, Leu, Met
or Val; Xaa39 is Ala, Gly, Pro, Ser, or Thr; Xaa40 is Ala, Gly,
Pro, Ser, or Thr; Xaa41 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa42
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa43 is Ala, Gly, Pro, Ser,
or Thr; Xaa44 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile,
Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa45 is Ala,
Gly, Pro, Ser, or Thr; Xaa46 is Ala, Arg, Asn, Asp, Cys, Glu, Gln,
Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val;
Xaa47 is Ala, Gly, Pro, Ser, or Thr; Xaa48 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa49 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa50
is Ala, Gly, Pro, Ser, or Thr; Xaa51 is Ala, Gly, Pro, Ser, or Thr;
Xaa52 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa53 is Ala, Arg,
Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro,
Ser, Thr, Trp, Tyr or Val; Xaa54 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or
Val; Xaa55 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa56
is Ala, Arg, Asn, Asp, Cys, Glu, Gin, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa57 is Ala, Arg, Asn, Asp,
Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr or Val; Xaa58 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa59
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa60 is Ala, Arg, Asn, Asp,
Cys, Glu, Gin, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr,
Trp, Tyr, Val or a peptide bond; Xaa61 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr, Val or a peptide bond; Xaa62 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr,
Val or a peptide bond; Xaa63 is Ala, Arg, Asn, Asp, Cys, Glu, Gln,
Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr, Val or
a peptide bond; Xaa64 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa65
is Ala, Gly, Pro, Ser, or Thr; Xaa66 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr or Val; Xaa67 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His,
Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa68 is
Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa69 is Ala, Gly,
Pro, Ser, or Thr; Xaa72 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly,
His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa73
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr, Val or a peptide bond; Xaa74 is Ala,
Arg, Asn, Asp, Cys, Glu, Gin, Gly, His, Ile, Leu, Lys, Met, Phe,
Pro, Ser, Thr, Trp, Tyr, Val or a peptide bond; Xaa76 is Ala, Gly,
Pro, Ser, or Thr; Xaa77 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser
or Thr; Xaa78 is Leu or Met; Xaa79 is Arg, Asn, Asp, Gln, Glu, His,
Lys, Ser or Thr; Xaa80 is Ala, Gly, Pro, Ser, or Thr; Xaa81 is Leu
or Met; Xaa82 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr;
Xaa83 is Ile, Leu, Met or Val; Xaa84 is Ala, Arg, Asn, Asp, Cys,
Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp,
Tyr or Val; Xaa85 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His,
Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa86 is
Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa87 is Arg, Asn, Asp, Gln,
Glu, His, Lys, Ser or Thr; Xaa89 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or
Val; Xaa90 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile,
Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr, Val or a peptide bond;
Xaa91 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa92 is Arg, Asn,
Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa93 is Cys, Ile, Leu, Met,
Phe, Trp, Tyr or Val; Xaa94 is Ala, Arg, Asn, Asp, Cys, Glu, Gln,
Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val;
Xaa95 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu,
Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa96 is Arg, Gln,
Glu, or Lys; Xaa97 is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or
Thr; Xaa98 is Ile or Val; Xaa99 is Ala, Arg, Asn, Asp, Cys, Glu,
Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or
Val; Xaa101 is Leu or Met; Xaa102 is Ile, Leu, Met or Val; Xaa103
is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met,
Phe, Pro, Ser, Thr, Trp, Tyr or Val; Xaa104 is Gln or Glu; Xaa105
is Arg, Asn, Asp, Gln, Glu, His, Lys, Ser or Thr; Xaa107 is Ala or
Gly; Xaa109 is Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile,
Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr or Val.
[0121] (2) Biochemical, Structural and Functional Properties of
Bone Morphogenic Proteins
[0122] In its mature, native form, natural-sourced osteogenic
protein is a glycosylated dimer, typically having an apparent
molecular weight of about 30-36 kDa as determined by SDS-PAGE. When
reduced, the 30 kDa protein gives rise to two glycosylated peptide
subunits having apparent molecular weights of about 16 kDa and 18
kDa. In the reduced state, the protein has no detectable osteogenic
activity. The unglycosylated protein, which also has osteogenic
activity, has an apparent molecular weight of about 27 kDa. When
reduced, the 27 kDa protein gives rise to two unglycosylated
polypeptide chains, having molecular weights of about 14 kDa to 16
kDa. Typically, the naturally occurring osteogenic proteins are
translated as a precursor, having an N-terminal signal peptide
sequence typically less than about 30 residues, followed by a "pro"
domain that is cleaved to yield the mature C-terminal domain. The
signal peptide is cleaved rapidly upon translation, at a cleavage
site that can be predicted in a given sequence using the method of
Von Heijne (1986) Nucleic Acids Research 14:4683-4691. Osteogenic
proteins useful herein include any known naturally-occurring native
proteins including allelic, phylogenetic counterpart and other
variants thereof, whether naturally-occurring or biosynthetically
produced (e.g., including "muteins" or "mutant proteins"), as well
as new, osteogenically active members of the general morphogenic
family of proteins.
[0123] In still another preferred embodiment, useful osteogenically
active proteins have polypeptide chains with amino acid sequences
comprising a sequence encoded by a nucleic acid that hybridizes,
under low, medium or high stringency hybridization conditions, to
DNA or RNA encoding reference osteogenic sequences, e.g.,
C-terminal sequences defining the conserved seven cysteine domains
of OP-1, OP-2, BMP2, 4, 5, 6, 60A, GDF5, GDF6, GDF7 and the like.
As used herein, high stringent hybridization conditions are defined
as hybridization according to known techniques in 40% formamide,
5.times.SSPE, 5.times. Denhardt's Solution, and 0.1% SDS at
37.degree. C. overnight, and washing in 0.1.times.SSPE, 0.1% SDS at
50.degree. C. Standard stringency conditions are well characterized
in commercially available, standard molecular cloning texts. See,
for example, Molecular Cloning A Laboratory Manual, 2nd Ed., ed. by
Sambrook, Fritsch and Maniatis (Cold Spring Harbor Laboratory
Press: 1989); DNA Cloning, Volumes I and II (D. N. Glover ed.,
1985); Oligonucleotide Synthesis (M. J. Gait ed., 1984): Nucleic
Acid Hybridization (B. D. Hames & S. J. Higgins eds. 1984); and
B. Perbal, A Practical Guide To Molecular Cloning (1984).
[0124] Other members of the TGF-.beta. superfamily of related
proteins having utility in the practice of the instant invention
include poor refolder proteins among the list: TGF-.beta.1,
TGF-.beta.2, TGF-.beta.3, TGF-.beta.4 and TGF-.beta.5, various
inhibins, activins, BMP-11, and MIS, to name a few. FIG. 5C lists
the C-terminal residues defining the finger 2 subdomain of various
known members of the TGF-.beta. superfamily. Any one of the
proteins on the list that is a poor refolder can be improved by the
methods of the invention, as can other known or discoverable family
members.
[0125] B. Production of Recombinant Proteins
[0126] As mentioned above, the constructs of the invention can be
manufactured by using conventional recombinant DNA methodologies
well known and thoroughly documented in the art, as well as by
using well-known biosynthetic and chemosynthetic methodologies
using routine peptide or nucleotide chemistries and automated
peptide or nucleotide synthesizers. Such routine methodologies are
described for example in the following publications, the teachings
of which are incorporated by reference herein: Hilvert, 1 Chem.
Biol. 201-3 (1994); Muir et al., 95 Proc. Natl. Acad. Sci. USA
6705-10 (1998); Wallace, 6 Curr. Opin. Biotechnol. 403-10 (1995);
Miranda et al., 96 Proc. Natl. Acad. Sci. USA 1181-86 (1999); Liu
et al., 91 Proc. Natl. Acad. Sci. USA 6584-88 (1994). Suitable for
use in the present invention are naturally-occurring amino acids
and nucleotides; non-naturally occurring amino acids and
nucleotides; modified or unusual amino acids; modified bases; amino
acid sequences that contain post-translaterially modified amino
acids and/or modified linkages, cross-links and end caps,
non-peptidyl bonds, etc.; and, further including without
limitation, those moieties disclosed in the World Intellectual
Property Organization (WIPO) Handbook on Industrial Property
Information and Documentation, Standard St. 25 (1998) including
Tables 1 through 6 in Appendix 2, herein incorporated by reference.
Equivalents of the foregoing will be appreciated by the skilled
artisan relying only on routine experimentation together with the
knowledge of the art.
[0127] For example, the contemplated DNA constructs may be
manufactured by the assembly of synthetic nucleotide sequences
and/or joining DNA restriction fragments to produce a synthetic DNA
molecule. The DNA molecules then are ligated into an expression
vehicle, for example an expression plasmid, and transfected into an
appropriate host cell, for example E. coli. The contemplated
protein construct encoded by the DNA molecule then is expressed,
purified, refolded, tested in vitro for certain attributes, e.g.,
binding activity with a receptor having binding affinity for the
template TGF-.beta. superfamily member, and subsequently tested to
assess whether the biosynthetic construct mimics other preferred
attributes of the template superfamily member.
[0128] Alternatively, a library of synthetic DNA constructs can be
prepared simultaneously for example, by the assembly of synthetic
nucleotide sequences that differ in nucleotide composition in a
preselected region. For example, it is contemplated that during
production of a construct based upon a specific TGF-.beta.
superfamily member, the artisan can choose appropriate finger and
heel regions for such a superfamily member (for example from FIGS.
5-6). Once the appropriate finger and heel regions have been
selected, the artisan then can produce synthetic DNA encoding these
regions. For example, if a plurality of DNA molecules encoding
different linker sequences are included into a ligation reaction
containing DNA molecules encoding finger and heel sequences, by
judicious choice of appropriate restriction sites and reaction
conditions, the artisan may produce a library of DNA constructs
wherein each of the DNA constructs encode finger and heel regions
but connected by different linker sequences. The resulting DNAs
then are ligated into a suitable expression vehicle, i.e., a
plasmid useful in the preparation of a phage display library,
transfected into a host cell, and the polypeptides encoded by the
synthetic DNAs expressed to generate a pool of candidate proteins.
The pool of candidate proteins subsequently can be screened to
identify specific proteins having binding affinity and/or
selectivity for a pre-selected receptor.
[0129] Screening can be performed by passing a solution comprising
the candidate proteins through a chromatography column containing
surface immobilized receptor. Then proteins with the desired
binding specificity are eluted, for example by means of a salt
gradient and/or a concentration gradient of the template TGF-.beta.
superfamily member. Nucleotide sequences encoding such proteins
subsequently can be isolated and characterized. Once the
appropriate nucleotide sequences have been identified, the lead
proteins subsequently can be produced, either by conventional
recombinant DNA or peptide synthesis methodologies, in quantities
sufficient to test whether the particular construct mimics the
activity of the template TGF-.beta. superfamily member.
[0130] It is contemplated that, which ever approach is adopted to
produce DNA molecules encoding constructs of the invention, the
tertiary structure of the preferred proteins can subsequently be
modulated in order to optimize binding and/or biological activity
by, for example, by a combination of nucleotide mutagenesis
methodologies aided by the principles described herein and phage
display methodologies. Accordingly, an artisan can produce and test
simultaneously large numbers of such proteins.
[0131] (1) Gene Synthesis.
[0132] The processes for manipulating, amplifying, and recombining
DNA which encode amino acid sequences of interest generally are
well known in the art, and therefore, are not described in detail
herein. Methods of identifying and isolating genes encoding members
of the TGF-.beta. superfamily and their cognate receptors also are
well understood, and are described in the patent and other
literature.
[0133] Briefly, the construction of DNAs encoding the biosynthetic
constructs disclosed herein is performed using known techniques
involving the use of various restriction enzymes which make
sequence specific cuts in DNA to produce blunt ends or cohesive
ends, DNA ligases, techniques enabling enzymatic addition of sticky
ends to blunt-ended DNA, construction of synthetic DNAs by assembly
of short or medium length oligonucleotides, cDNA synthesis
techniques, polymerase chain reaction (PCR) techniques for
amplifying appropriate nucleic acid sequences from libraries, and
synthetic probes for isolating genes of members of the TGF-b
superfamily and their cognate receptors. Various promoter sequences
from bacteria, mammals, or insects to name a few, and other
regulatory DNA sequences used in achieving expression, and various
types of host cells are also known and available. Conventional
transfection techniques, and equally conventional techniques for
cloning and subcloning DNA are useful in the practice of this
invention and known to those skilled in the art. Various types of
vectors may be used such as plasmids and viruses including animal
viruses and bacteriophages. The vectors may exploit various marker
genes which impart to a successfully transfected cell a detectable
phenotypic property that can be used to identify which of a family
of clones has successfully incorporated the recombinant DNA of the
vector.
[0134] One method for obtaining DNA encoding the biosynthetic
constructs disclosed herein is by assembly of synthetic
oligonucleotides produced in a conventional, automated,
oligonucleotide synthesizer followed by ligation with appropriate
ligases. For example, overlapping, complementary DNA fragments may
be synthesized using phosphoramidite chemistry, with end segments
left unphosphorylated to prevent polymerization during ligation.
One end of the synthetic DNA is left with a "sticky end"
corresponding to the site of action of a particular restriction
endonuclease, and the other end is left with an end corresponding
to the site of action of another restriction endonuclease. The
complimentary DNA fragments are ligated together to produce a
synthetic DNA construct.
[0135] Alternatively nucleic acid strands encoding finger 1, finger
2 and heel regions may be isolated from libraries of nucleic acids,
for example, by colony hybridization procedures such as those
described in Sambrook et al. eds. (1989) "Molecular Cloning",
Coldspring Harbor Laboratories Press, NY, and/or by PCR
amplification methodologies, such as those disclosed in Innis et
al. (1990) "PCR Protocols, A guide to methods and applications",
Academic Press. The nucleic acids encoding the finger and heel
regions then are joined together to produce a synthetic DNA
encoding the biosynthetic single-chain morphon construct of
interest.
[0136] It is appreciated, however, that a library of DNA constructs
encoding a plurality of morphons may be produced simultaneously by
standard recombinant DNA methodologies, such as the ones, described
above, For example, the skilled artisan by the use of cassette
mutagenesis or oligonucleotide directed mutagenesis may produce,
for example, a series of DNA constructs each of which contain
different DNA sequences within a predefined location, e.g., within
a DNA cassette encoding a linker sequence. The resulting library of
DNA constructs subsequently may be expressed, for example, in a
phage display library and any protein constructs that binds to a
specific receptor may be isolated by affinity purification, e.g.,
using a chromatographic column comprising surface immobilized
receptor (see section V below). Once molecules that bind the
preselected receptor have been isolated, their binding and agonist
properties may be modulated using the empirical refinement
techniques also discussed in section V, below.
[0137] Methods of mutagenesis of proteins and nucleic acids are
well known and well described in the art. See, e.g., Sambrook et
al., (1990) Molecular Cloning: A Laboratory Manual., 2d ed. (Cold
Spring Harbor, N.Y.: Cold Spring Harbor Laboratory Press). Useful
methods include PCR (overlap extension, see, e.g., PCR Primer
(Dieffenbach and Dveksler, eds., Cold Spring Harbor Press, Cold
Spring Harbor, N.Y., 1995, pp. 603-611); cassette mutagenesis and
single-stranded mutagenesis following the method of Kunkel. It will
be appreciated by the artisan that any suitable method of
mutagenesis can be utilized and the mutagenesis method is not
considered a material aspect of the invention. The nucleotide
codons competent to encode amino acids, including arginine (Arg),
glutamic acid (Glu) and aspartic acid (Asp) also are well known and
described in the art. See, for example, Lehninger, Biochemistry,
(Worth Publishers, N.Y., N.Y.) Standard codons encoding arginine,
glutamic acid and aspartic acid are: Arg: CGU, CGC, CGA, CGG, AGA,
AGG; Glu: GAA, GAG; and Asp: GAU, GAC. Chimeric constructs of the
invention can readily be constructed by aligning the nucleic acid
sequences of protein regions, or domains to be switched, and
identifying compatible splice sites and/or constructing suitable
crossover sequences using PCR overlap extension.
[0138] The mutant forms of TGF-.beta. family members of the present
invention can be produced in bacteria using standard, well-known
methods. Full-length mature forms or shorter sequences defining
only the C-terminal seven cysteine domain can be provided to the
host cell. It may be preferred to modify the N-terminal sequences
of the mutant forms of the protein in order to optimize bacterial
expression. For example, the preferred form of native OP-1 for
bacterial expression is the sequence encoding the mature, active
sequence (residues 293-431 of SEQ No. 39 or a fragment thereof
encoding the C-terminal seven cysteine domain (e.g., residues
330-431 of SEQ ID NO: 39). A methionine can be introduced at
position 293, replacing the native serine residue, or it can
precede this serine residue. Alternatively, a methionine can be
introduced anywhere within the first thirty-six residues of the
natural sequence (residues 293-329), up to the first cysteine of
the TGF-.beta. domain. The DNA sequence further can be modified at
its N-terminus to improve purification, for example, by adding a
"hexa-his" tail to assist purification on an IMAC column; or by
using a FB leader sequence, which facilitates purification on an
IgG/column. These and other methods are well described and well
known in the art. Other bacterial species and/or proteins may
require or benefit from analogous modifications to optimize the
yield of the mutant BMP obtained therefrom. Such modifications are
well within the level of ordinary skill in the art and are not
considered material aspects of the invention.
[0139] The synthetic nucleic acids preferably are inserted into a
vector suitable for overexpression in the host cell of choice. Any
expression vector can be used, so long as it is capable of
directing the expression of a heterologous protein such as a BMP in
the host cell of choice. Useful vectors include plasmids,
phagemids, mini chromosomes and YACs, to name a few. Other vector
systems are well known and characterized in the art. The vector
typically includes a replicon, one or more selectable marker gene
sequences, and means for maintaining a high copy number of the
vector in the host cell. Well known selectable marker genes include
antibiotics like ampicillin, tetracycline and the like, as well as
resistance to heavy metals. Useful selectable marker genes for use
in yeast cells include the URA3, LEU2, HIS3 or TRP1 gene for use
with an auxotrophic yeast mutant host. In addition, the vector also
includes a suitable promoter sequence for expressing the gene of
interest and which may or may not be inducible, as desired, as well
as useful transcription and translation initiation sites,
terminators, and other sequences that can maximize transcription
and translation of the gene of interest. Well characterized
promotors particularly useful in bacterial cells include the lac,
tac, trp, and tpp promoters, to name a few. Promoters useful in
yeast include ADHI, ADHII, or PHO5 promoter, for example.
[0140] Suitable host cells include microbial cells such as Bacillus
subtilis (B. subtilis), species of Pseudomonas, Escherichia coli
(E. coli), and yeast cells, e.g., Saccharomyces cereviceae. Other
hosts cells, for example mammalian cells such as CHO, can be
used.
[0141] The gene of interest can be transformed into the host cell
of choice using standard microbiology techniques (electroporation
or calcium chloride, for example) and the cells induced to grow
under suitable conditions. Cell culturing media are well described
in the art, including numerous well known texts, including
Sambrook, et al. Useful media include LB (Luria's Broth) and
Dulbecco's DMEM. The overexpressed protein can be collected from
insoluble, refractile inclusion bodies by standard techniques,
including cell lysis or mechanical disruption of the cell
(Frenchpress, SLM Instruments, Inc, for example) followed by
centrifugation and resolubilization (see below).
[0142] For example, if the gene is to be expressed in E. coli, it
is cloned into an appropriate expression vector. This can be
accomplished by positioning the engineered gene downstream of a
promoter sequence such as Trp or Tac, and/or a gene coding for a
leader peptide such as fragment B of protein A (FB). During
expression, the resulting fusion proteins accumulate in refractile
bodies in the cytoplasm of the cells, and may be harvested after
disruption of the cells by French press or sonication. The isolated
refractile bodies then are solubilized, and the expressed proteins
folded and the leader sequence cleaved, if necessary, by methods
already established with many other recombinant proteins.
[0143] Expression of the engineered genes in eukaryotic cells
requires cells and cell lines that are easy to transfect, are
capable of stably maintaining foreign DNA with an unrearranged
sequence, and which have the necessary cellular components for
efficient transcription, translation, post-translation
modification, and secretion of the protein. In addition, a suitable
vector carrying the gene of interest also is necessary. DNA vector
design for transfection into mammalian cells should include
appropriate sequences to promote expression of the gene of interest
as described herein, including appropriate transcription
initiation, termination, and enhancer sequences, as well as
sequences that enhance translation efficiency, such as the Kozak
consensus sequence. Preferred DNA vectors also include a marker
gene and means for amplifying the copy number of the gene of
interest. A detailed review of the state of the art of the
production of foreign proteins in mammalian cells, including useful
cells, protein expression-promoting sequences, marker genes, and
gene amplification methods, is disclosed in Bendig (1988) Genetic
Engineering 7:91-127.
[0144] The best characterized transcription promoters useful for
expressing a foreign gene in a particular mammalian cell are the
SV40 early promoter, the adenovirus promoter (AdMLP), the mouse
metallothionein-I promoter (mMT-I), the Rous sarcoma virus (RSV)
long terminal repeat (LTR), the mouse mammary tumor virus long
terminal repeat (MMTV-LTR), and the human cytomegalovirus major
intermediate-early promoter (hCMV). The DNA sequences for all of
these promoters are known in the art and are available
commercially.
[0145] The use of a selectable DHFR gene in a dhfr.sup.- cell line
is a well characterized method useful in the amplification of genes
in mammalian cell systems. Briefly, the DHFR gene is provided on
the vector carrying the gene of interest, and addition of
increasing concentrations of the cytotoxic drug methotrexate, which
is metabolized by DHFR, leads to amplification of the DHFR gene
copy number, as well as that of the associated gene of interest.
DHFR as a selectable, amplifiable marker gene in transfected
chinese hamster ovary cell lines (CHO cells) is particularly well
characterized in the art. Other useful amplifiable marker genes
include the adenosine deaminase (ADA) and glutamine synthetase (GS)
genes.
[0146] The choice of cells/cell lines is also important and depends
on the needs of the experimenter. COS cells provide high levels of
transient gene expression, providing a useful means for rapidly
screening the biosynthetic constructs of the invention. COS cells
typically are transfected with a simian virus 40 (SV40) vector
carrying the gene of interest. The transfected COS cells eventually
die, thus preventing the long term production of the desired
protein product. However, transient expression does not require the
time consuming process required for the development of a stable
cell line, and thus provides a useful technique for testing
preliminary constructs for binding activity.
[0147] The various cells, cell lines and DNA sequences that can be
used for mammalian cell expression of the single-chain constructs
of the invention are well characterized in the art and are readily
available. Other promoters, selectable markers, gene amplification
methods and cells also may be used to express the proteins of this
invention. Particular details of the transfection, expression, and
purification of recombinant proteins are well documented in the art
and are understood by those having ordinary skill in the art.
Further details on the various technical aspects of each of the
steps used in recombinant production of foreign genes in mammalian
cell expression systems can be found in a number of texts and
laboratory manuals in the art, such as, for example, F. M. Ausubel
et al, ed., Current Protocols in Molecular Biology, John Wiley
& Sons, New York, (1989).
[0148] C. Refolding Considerations
[0149] The protein, once isolated from inclusion bodies, is
solubilized using a denaturant or chaotropic agent such as
guanidine HCl or urea, preferably in the range of about 4-9 M and
at an elevated temperature (e.g., 25-37.degree. C.) and/or basic pH
(8-10). Alternatively, the proteins can be solubilized by
acidification, e.g., with acetic acid or trifluoroacetic acid,
generally at a pH in the range of 1-4. Preferably, a reducing agent
such as .beta.-mercaptoethanol or dithiothreitol (DTT) is used in
conjunction with the solubilizing agent. The solubilized
heterologous protein can be purified further from solubilizing
chaotropes by dialysis and/or by known chromatographic methods such
as size exclusion chromatography, ion exchange chromatography, or
reverse phase high performance liquid chromatography (RP-HPLC), for
example.
[0150] The solubilized protein can be refolded as follows. The
dissolved protein is diluted in a refolding medium, typically a
Tris-buffered medium having a pH in the range of about pH 5.0-10.0,
preferably in the range of about pH 6-9 and one which includes a
detergent and/or chaotropic agent. Useful commercially available
detergents can be ionic, nonionic or zwitterionic, such as NP40
(Nonidet 40), CHAPS (such as
3-[(3-cholamido-propyl)dimethylammonio]-1-propane-sulfate,
digitonin, deoxycholate, or N-octyl glucoside. Useful chaotropic
agents include guanidine, urea, or arginine. Preferably the
detergent or chaotropic agent is present at a concentration in the
range of about 0.1-10M, preferably in the range of about 0.5-4M.
When CHAPS is the detergent, it preferably comprises about 0.5-5%
of the solution, more preferably about 1-3% of the solution.
Preferably the solution also includes a suitable redox system such
as the oxidized and reduced forms of glutathione, DTT,
.beta.-mercaptoethanol, .beta.-mercaptomethanol, cysteine or
cystamine, to name a few. Preferably, the redox systems are present
at ratios of reductant to oxidant in the range of about 1:1 to
about 5:1. When the glutathione redox system is used, the ratio of
reduced glutathione to oxidized glutathione is preferably is in the
range of about 0.5 to 5; more preferably 1 to 1; and most
preferably 2 to 1 of reduced form to oxidized form. Preferably the
buffer also contains a salt, typically NaCl, present in the range
of about 0.25M-2.5 M, preferably in the range of about 0.5-1.5M,
most preferably in the range of about 1M. One skilled in the art
will recognize that the above conditions and media may be varied
using no more than ordinary experimentation. Such variations and
modifications are within the scope of the present invention.
[0151] Preferably the protein concentration for a given refolding
reaction is in the range of about 0.001-1.0 mg/ml, more preferably
it is in the range of about 0.05-0.25 mg/ml, most preferably in the
range of about 0.075-0.125 mg/ml. As will be appreciated by the
skilled artisan, higher concentrations tend to produce more
aggregates. Where heterodimers are to be produced (for example an
OP1/BMP2 or BMP2/BMP6 heterodimer) preferably the individual
proteins are provided to the refolding buffer in equal amounts.
[0152] Typically, the refolding reaction takes place at a
temperature range from about 4.degree. C. to about 25.degree. C.
More preferably, the refolding reaction is performed at 4.degree.
C., and allowed to go to completion. Refolding typically is
complete in about one to seven days, generally within 16-72 hours
or 24-48 hours, depending on the protein. As will be appreciated by
the skilled artisan, rates of refolding can vary by protein, and
longer and shorter refolding times are contemplated and within the
scope of the present invention. As used herein, a "good refolder"
protein is one where at least 20% of the protein is present in
dimeric form following a folding reaction when compared to the
total protein in the refolding reaction, as measured by any of the
refolding assays described herein and without requiring further
purification. Native BMPs that are considered in the art to be
"good refolder" proteins include BMP2, CDMP1, CDMP2 and CDMP3.
BMP-3 also refolds reasonably well. In contrast, a "poor refolder"
protein yields less than 1% of properly-folded protein.
[0153] Properly refolded dimeric proteins readily can be assessed
using any of a number of well known and well characterized assays.
In particular, any one or more of three assays, all well known and
well described in the art, and further described below can be used
to advantage. Useful refolding assays include one or more of the
following. First, the presence of dimers can be detected visually
either by standard SDS-PAGE in the absence of a reducing agent such
as DTT or by HPLC (e.g., C18 reverse phase HPLC). BMP dimeric
proteins have an apparent molecular weight in the range about 28-36
kDa, as compared to monomeric subunits, which have an apparent
molecular weight of about 14-18 kDa. The dimeric protein can
readily be visualized on an electrophoresis gel by comparison to
commercially available molecular weight standards. The dimeric
protein also elutes from a C18 RP HPLC (45-50% acetonitrile: 0.1%
TFA) at about 19 minutes (mammalian produced hOP-1 elutes at 18.95
minutes).
[0154] A second assay evaluates the presence of dimer by its
ability to bind to hydroxyapatite. Properly-folded dimer binds a
hydroxyapatite column well in the presence of 0.1-0.2M NaCl (dimer
elutes at 0.25 M NaCl) as compared to monomer, which does not bind
substantially at those concentrations (monomer elutes at 0.1M
NaCl).
[0155] A third assay evaluates the presence of dimer by the
protein's resistant to trypsin or pepsin digestion. The folded
dimeric species is substantially resistant to both enzymes,
particularly trypsin, which cleaves only a small portion of the
N-terminus of the mature protein, leaving a biologically active
dimeric species only slightly smaller in size than the untreated
dimer. By contrast, the monomer is substantially degraded. In the
assay, the protein is subjected to an enzyme digest using standard
conditions, e.g., digestion in a standard buffer such as 50 mM Tris
buffer, pH 8, containing 4 M urea, 100 mM NaCl, 0.3% Tween-80 and
20 mM methylamine. Digestion is allowed to occur at 37.degree. C.
for on the order of 16 hours, and the product visualized by any
suitable means, preferably SDS-PAGE.
[0156] The biological activity of the refolded TGF-.beta. family
protein readily can be assessed by any of a number of means. A
BMP's ability to induce endochondral bone formation can be
evaluated using the well characterized rat subcutaneous bone assay,
described in the art and in detail below. In the assay bone
formation is measured by histology, as well as by alkaline
phosphatase and/or osteoclacin production. In addition, osteogenic
proteins having high specific bone forming activity, such as OP-1,
BMP-2, BMP-4, BMP5 and BMP6, also induce alkaline phosphatase
activity in an in vitro rat osteoblast or osteosarcoma cell-based
assay. Such assays are well described in the art and are detailed
herein below. See, for example, Sabokdar et al. (1994) Bone and
Mineral 27:57-67; Knutsen et al. (1993) Biochem. Biophys. Res.
Commun. 194:1352-1358; and Maliakal et al. (1994) Growth Factors
1:227-234). By contrast, osteogenic proteins having low specific
bone forming activity, such as CDMP-1 and CDMP-2, for example, do
not induce similar levels of alkaline phosphatase activity in the
cell based osteoblast assay. The assay thus provides a ready method
for evaluating biological activity mutants of BMPs. For example,
CDMP 1, CDMP2 and CMDP3 all are competent to induce bone formation,
although with a lower specific activity than BMP2, BMP4, BMP5, BMP6
or OP-1. Conversely, BMP2, BMP4, BMP5, BMP6 and OP-1 all can induce
articular cartilage formation, albeit with a lower specific
activity than CDMP 1, CDMP2 or CDMP3. Accordingly, a CDMP mutant
competent to induce alkaline phosphatase activity in the cell-based
assay of Example 5 is expected to demonstrate a higher specific
bone forming activity in the rat animal bioassay. Similarly, an
OP-1 mutant containing a substitution present in a corresponding
position of a CDMP 1, CDMP2 or CDMP3 protein, and competent to
induce bone in the rat assay but not to induce alkaline phosphatase
activity in the cell based assay, is expected to have a higher
specific articular cartilage inducing activity in an in vivo
articular cartilage assay. As described herein below, a suitable in
vitro assay for CDMP activity utilizes mouse embyronic
osteoprogenitor or carcinoma cells, such as ATDC5 cells. See
Example 6, below.
[0157] TGF-.beta. activity can be readily evaluated by the
protein's ability to inhibit epithelial cell growth. A useful, well
characterized in vitro assay utilizes mink lung cells or melanoma
cells. See Example 7. Other assays for other members of the TGF-8
superfamily are well described in the literature and can be
performed without undue experimentation.
[0158] D. Formulation and Bioactivity
[0159] The resulting chimeric proteins can be provided to an
individual as part of a therapy to enhance, inhibit, or otherwise
modulate in vivo events, such as but not limited to, the binding
interaction between a TGF-.beta. superfamily member and one or more
of its cognate receptors. The constructs may be formulated in a
pharmaceutical composition, as described below, and may be
administered in morphogenic effective amounts by any suitable
means, preferably directly or systematically, e.g., parenterally or
orally. Resulting DNA constructs encoding preferred chimeric
proteins can also be administered directly to a recipient for gene
therapeutic purposes; such DNAs can be administered with or without
carrier components, or with or without matrix components.
Alternatively, cells transferred with such DNA constructs can be
implanted in a recipient. Such materials and methods are well-known
in the art.
[0160] Where any of the constructs disclosed here are to be
provided directly (e.g., locally, as by injection, to a desired
tissue site), or parentally, such as by intravenous, subcutaneous,
intramuscular, intraorbital, ophthalmic, intraventricular,
intracranial, intracapsular, intraspinal, intracisternal,
intraperitoneal, buccal, rectal, vaginal, intranasal or by aerosol
administration, the therapeutic composition preferably comprises
part of an aqueous solution. The solution preferably is
physiologically acceptable so that in addition to delivery of the
desired construct to the patient, the solution does not otherwise
adversely affect the patient's electrolyte and volume balance. The
aqueous medium for the therapeutic molecule thus may comprise, for
example, normal physiological saline (0.9% NaCl, 0.15M), pH 7-7.4
or other pharmaceutically acceptable salts thereof.
[0161] Useful solutions for oral or parenteral administration may
be prepared by any of the methods well known in the pharmaceutical
art, described, for example, in Remington's Pharmaceutical
Sciences, (Gennaro, A., ed.), Mack Pub., 1990. Formulations may
include, for example, polyalkylene glycols such as polyethylene
glycol, oils of vegetable origin, hydrogenated naphthalenes, and
the like. Formulations for direct administration, in particular,
may include glycerol and other compositions of high viscosity.
Biocompatible, preferably bioresorbable polymers, including, for
example, hyaluronic acid, collagen, tricalcium phosphate,
polybutyrate, polylactide, polyglycolide and lactide/glycolide
copolymers, may be useful excipients to control the release of the
morphogen in vivo.
[0162] Other potentially useful parenteral delivery systems for
these therapeutic molecules include ethylene-vinyl acetate
copolymer particles, osmotic pumps, implantable infusion systems,
and liposomes. Formulations for inhalation administration may
contain as excipients, for example, lactose, or may be aqueous
solutions containing, for example, polyoxyethylene-9-lauryl ether,
glycocholate and deoxycholate, or oily solutions for administration
in the form of nasal drops, or as a gel to be applied
intranasally.
[0163] Finally, therapeutic molecules may be administered alone or
in combination with other molecules known to effect tissue
morphogenesis, i.e., molecules capable of tissue repair and
regeneration and/or inhibiting inflammation. Examples of useful
cofactors for stimulating bone tissue growth in osteoporotic
individuals, for example, include but are not limited to, vitamin
D.sub.3, calcitonin, prostaglandins, parathyroid hormone,
dexamethasone, estrogen and IGF-I or IGF-II. Useful cofactors for
nerve tissue repair and regeneration may include nerve growth
factors. Other useful cofactors include symptom-alleviating
cofactors, including antiseptics, antibiotics, antiviral and
antifungal agents and analgesics and anesthetics.
[0164] Therapeutic molecules further can be formulated into
pharmaceutical compositions by admixture with pharmaceutically
acceptable nontoxic excipients and carriers. As noted above, such
compositions may be prepared for parenteral administration,
particularly in the form of liquid solutions or suspensions; for
oral administration, particularly in the form of tablets or
capsules; or intranasally, particularly in the form of powders,
nasal drops or aerosols. Where adhesion to a tissue surface is
desired the composition may include the biosynthetic construct
dispersed in a fibrinogen-thrombin composition or other bioadhesive
such as is disclosed, for example in PCT US91/09275, the disclosure
of which is incorporated herein by reference. The composition then
may be painted, sprayed or otherwise applied to the desired tissue
surface. The compositions can be formulated for parenteral or oral
administration to humans or other mammals in therapeutically
effective amounts, e.g., amounts which provide appropriate
concentrations of the morphon to target tissue for a time
sufficient to induce the desired effect.
[0165] Where the therapeutic molecule comprises part of a tissue or
organ preservation solution, any commercially available
preservation solution may be used to advantage. For example, useful
solutions known in the art include Collins solution, Wisconsin
solution, Belzer solution, Eurocollins solution and lactated
Ringer's solution. A detailed description of preservation solutions
and useful components may be found, for example, in U.S. Pat. No.
5,002,965, the disclosure of which is incorporated herein by
reference.
[0166] It is contemplated that some of the protein constructs, for
example those based upon members of the Vg/dpp subgroup, will also
exhibit high levels of activity in vivo when combined with a
matrix. See for example, U.S. Pat. No. 5,266,683 the disclosure of
which is incorporated by reference herein. The currently preferred
matrices are xenogenic, allogenic or autogenic in nature. It is
contemplated, however, that synthetic materials comprising
polylactic acid, polyglycolic acid, polybutyric acid, derivatives
and copolymers thereof can also be used to generate suitable
matrices. Preferred synthetic and naturally derived matrix
materials, their preparation, methods for formulating them with the
morphogenic proteins of the invention, and methods of
administration are well known in the art and so are not discussed
in detailed herein. See for example, U.S. Pat. No. 5,266,683, the
disclosure of which is herein incorporated by reference. It is
further contemplated that binding to, adherence to or association
with a matrix or the metal surface of a prosthetic device is an
attribute that can be altered using the materials and methods
disclosed herein. For example, devices comprising a matrix and an
osteoactive construct of the present invention having enhanced
matrix-adherent properties can be used as a slow-release device.
The skilled artisan will appreciate the variation and manipulations
now possible in light of the teachings herein.
[0167] As will be appreciated by those skilled in the art, the
concentration of the compounds described in a therapeutic
composition will vary depending upon a number of factors, including
the morphogenic effective amount to be administered, the chemical
characteristics (e.g., hydrophobicity) of the compounds employed,
and the route of administration: The preferred dosage of drug to be
administered also is likely to depend on such variables as the type
and extent of a disease, tissue loss or defect, the overall health
status of the particular patient, the relative biological efficacy
of the compound selected, the formulation of the compound, the
presence and types of excipients in the formulation, and the route
of administration. In general terms, the therapeutic molecules of
this invention may be provided to and individual where typical
doses range from about 10 ng/kg to about 1 g/kg of body weight per
day; with a preferred dose range being from about 0.1 mg/kg to 100
mg/kg of body weight.
[0168] II. Specific Modified Protein Constructs
[0169] Generally, the present invention relates to four types of
modified TGF-.beta. family protein constructs: (1) TGF-.beta.
family proteins which are truncated at the N-terminal region, (2)
"latent" proteins that can be activated upon cleavage, including,
but not limited to, release of an N-terminal sequence (e.g., by
acid cleavage or protease treatment), (3) fusion proteins with
specific binding capabilities and (4) heterodimers consisting of
naturally-occurring or modified subunits of TGF-.beta. family
members. Particular species of these morphogen constructs are
described in detail below. The species exemplified below generally
relate to modified morphogen or osteogenic protein constructs, but
the skilled practitioner will appreciate that these constructs are
representative of similar constructs that can be generated with
other members of the TGF-.beta. super family.
[0170] According to the present invention, the attributes of native
BMPs or other members of the TGF-.beta. superfamily of proteins,
including heterodimers and homodimers thereof, are altered by
modifying the N-terminus of a native protein to alter one or more
biological properties of a BMP or TGF-.beta. superfamily member. As
a result of this discovery, it is possible to design, TGF-.beta.
superfamily proteins that (1) are expressed recombinantly in
prokaryotic or eukaryotic cells or synthesized using polypeptide
synthesizers; (2) have altered folding attributes; (3) have altered
solubility under neutral pHs, including but not limited to
physiologically compatible conditions; (4) have altered isoelectric
points; (5) have altered stability; (6) have an altered tissue or
receptor specificity; (7) have a re-designed, altered biological
activity; and/or (8) have altered binding or adherence properties
to solid surfaces, such as but not limited to, biocompatible
matrices or metals. Thus, the present invention can provide
mechanisms for designing quick-release, slow-release and/or
timed-release formulations containing a preferred protein
construct. Other advantages and features will be evident from the
teachings below. Moreover, making use of the discoveries disclosed
herein, modified proteins having altered
surface-binding/surface-adherent properties can be designed and
selected. Surfaces of particular significance include, but are not
limited to, solid surfaces which can be naturally-occurring such as
bone; or porous particulate surfaces such as collagen or other
biocompatible matrices; or the flabricated surfaces of prosthetic
implants, including metals. As contemplated herein, virtually any
surface can be assayed for differential binding of constructs.
Thus, the present invention embraces a diversity of functional
molecules having alterations in their
surface-binding/surface-adherent properties, thereby rendering such
constructs useful for altered in vivo applications, including
slow-release, fast-release and/or timed-release formulations.
[0171] The skilled artisan will appreciate that mixing-and-matching
any one or more the above-recited attributes provides specific
opportunities to manipulate the uses of customized proteins (and
DNAs encoding the same). For example, the attribute of altered
stability can be exploited to manipulate the turnover of a protein
in vivo. Moreover, in the case of proteins also having attributes
such as altered re-folding and/or function, there is likely an
interconnection between folding, function and stability. See, for
example, Lipscomb et al., 7 Protein Sci. 765-73 (1998); and
Nikolova et al., 95 Proc. Natl. Acad. Sci. USA 14675-80 (1998). For
purposes of the present invention, stability alterations can be
routinely monitored using well-known techniques of circular
dichroism other indices of stability as a function of denaturant
concentration or temperature. One can also use routine scanning
calorimetry. Similarly, there is likely an interconnection between
any of the foregoing attributes and the attribute of solubility. In
the case of solubility, it is possible to manipulate this attribute
so that a protein construct is either more or less soluble under
physiologically-compatible conditions and it consequently diffuses
readily or remains localized, respectively, when administered in
vivo.
[0172] In addition to the aforementioned uses of protein constructs
with altered attributes, those with altered stability can also be
used to practical advantage for shelf-life, storage and/or shipping
considerations. Furthermore, on a related matter, altered stability
can also directly affect dosage considerations thereby, for
example, reducing the cost of treatment.
[0173] A particularly significant class of constructs are those
having altered binding to solubilized carriers or excipients. By
way of non-limiting example, an altered BMP having enhanced binding
to a solubilized carrier such as hyaluronic acid permits the
skilled artisan to administer an injectable formulation at a defect
site without loss or dilution of the BMP by either diffusion or
body fluids. Thus localization is maximized. The skilled artisan
will appreciate the variations made possible by the instant
teachings. Similarly, another class of constructs having altered
binding to body/tissue components can be exploited. By way of
non-limiting example, an altered BMP having diminished binding to
an in-situ inhibitor can be used to enhance repair of certain
tissues in vivo. It is well known in the art, for example, that
cartilage tissue is associated with certain proteins found in body
fluids and/or within cartilage per se that can inhibit the activity
of native BMPs. Chimeric constructs with altered binding
properties, however, can overcome the effects of these in-situ
inhibitors thereby enhancing repair, etc. The skilled artisan will
appreciate the variations made possible by the instant
teachings.
[0174] A. Truncation
[0175] There are different forms of OP-1, such as 23k, 17k, and
variable amounts of 15k, whereby the typical OP-1 preparation
contains all these species. N-terminal sequencing of purified
mature OP-1 has revealed heterogeneity showing that the N-terminus
can be more or less truncated. Through experiments with the species
retrieved by elution from RP-HPLC and by trypsin cleavage, ROS
activity is greatest among the 15k species. For example, truncated
mutant H2469 has relatively high activity by comparison with the
CHO-derived OP-1 standard. Whereas initial maturation occurs in
pro-OP-1 at the RXXR site resulting in the 17k species, a secondary
maturation by a different protease produces the most active 15k
species. Trypsin cleavage can mimic this secondary activation.
[0176] Trypsin treatment of mammalian OP-1 or E-coli refolded OP-1
results in increased ROS activity. Removal of the N-terminus of the
constructs described herein (e.g., hexa-his, collagen binding site,
and BMP-2 N-terminus) also resulted in increased activity in a ROS
assay. Truncation of OP-1 can increase solubility of the morphogen,
which can affect ROS activity. Thus, constructs can be created
having specific cleavage activity, that is, they are selective for
the type of cleavage and the timing of the cleavage. One skilled in
the art will appreciate that cleavage activity may differ based on
the system used (mammalian or prokaryote). For example, a mammalian
system may require that the morphogen construct include a pro
region, which in the context of the construct, could disrupt
folding and consequently will result (in the mammalian system), in
complete intracellular degradation with no protein at the end. It
may also be desirable to produce other constructs that include the
pro-protein form. In such constructs, the pro-domain can be
considered as another N-terminal element which can be cleaved to
obtain increased activity. The skilled practitioner will appreciate
that the uncleaved pro-protein can be utilized to take advantage of
its attributes (relating to solubility and activity).
[0177] The mutant proteins of the present invention exhibit
improved biological activity as well as extended half-life.
Further, increased activity observed with the truncated proteins of
the present invention may be due to elimination of basic residues
and/or the lowering of the protein's isoelectric point. Biological
activity and improved refolding can be enhanced when the modified
proteins of the present invention are combined with the
modifications described in copending application Ser. No. ______
[Atty Docket No. STK-076, filed on ______] and Ser. No. ______
[Atty Docket No. STK-077, filed on ______], the disclosures of
which are incorporated herein by reference.
[0178] B. N-Terminal Regions with Specific Properties
[0179] Additional modified proteins of the invention comprise
peptides of non-morphogen origin fused to the N-terminus of a
morphogen 7-cysteine domain. See e.g., FIGS. 7A-7E. The resulting
N-terminal fusion proteins have additional biological or
biochemical properties not present in the unmodified morphogen from
which the fusion is derived. Fusions of this type comprise a
morphogen 7-cysteine domain fused at its N-terminus to a protein,
or protein fragment, such as a collagen binding domain, an FB
domain of protein A, or a hexa-histidine region. For example, H2440
is OP-1 with a hexa-his tag attached to its N-terminus as a binding
domain for IMAC (immobilized metal affinity chromatography) resin.
(FIG. 7B). This protein has been purified over copper IMAC resin,
initially in its unfolded state, in the presence of urea. After the
purification of the unfolded protein on IMAC, followed by
refolding, the successfully refolded fraction is purified by
RP-HPLC. Such N-terminal fusion proteins display little or no
activity in a ROS assay, but are activated upon cleavage of the
N-terminal non-morphogen peptide to yield an active C-terminal
morphogen domain.
[0180] Particularly preferred are those engineered OP-1 constructs
that can target specific sites. For example, an OP-1 with a
N-terminal decapeptide collagen binding domain was constructed,
H2487, in which the decapeptide was placed 7 residues upstream from
the first cysteine (see FIG. 7A) to obtain specific and tight
binding of OP-1 to bone matrix. This new construct was successfully
refolded and active in the ROS assay, thereby indicating specific
bone forming activity. Other binding domains can be used similarly
to direct activity. For example, in the context of cartilage
repair, OP-1 can also be engineered to specifically adhere to
prosthetic devices. Other peptides, such as a peptide derived from
Clostridium collagenase, can also be explored for collagen binding
properties.
[0181] One of ordinary skill in the art will appreciate that the
techniques of the present invention can be used to generate
specific modified protein formulations that are capable of
environmentally-trigger- ed release of active protein at specific
sites under particular conditions. For example, changes in pH or
presence of a particular protease can modulate delivery and trigger
release of active protein.
[0182] Modifications of the leader sequence of a BMP or other
TGF-.beta. family members can also affect solubility, activity, and
expression of the protein. For example, construct H2528, which
utilizes CDMP-3 (thought to be useful for tendon repair) engineered
with a leader sequence as the FB subdomain of staphylococcus aureus
protein A, has improved expression of the osteogenic protein.
[0183] The skilled artisan will appreciate that the constructs of
the present invention can be engineered to contain a variety of
specialized, functional domains that can be attached to the
N-terminus of the TGF-.beta. family protein, provided that steric
interference and the consequent reduction in biological activity
are taken into account. Such constructs may require at least a
minimum spacing of the N-terminal addition from the 7-cysteine
domain to avoid inhibition of activity or folding. The skilled
artisan will appreciate that minimum spacing requirements will
depend upon the steric properties of the added moiety and the
ultimate intended activity of the modified construct, so that both
the specialized domain and the TGF-.beta. family protein will
retain their intended activities.
[0184] C. Latent BMPs
[0185] The present invention also takes advantage of the surprising
discovery of the extent to which the N-terminus can effect the
solubility and activity of the fusion proteins, since truncations
of the OP-1 N-terminus had no negative effects on the protein. In
addition, the crystal structure of OP-1 had not revealed any
topological information regarding the N-terminus.
[0186] The N-terminal fusion proteins described herein are useful
for providing latent (i.e. inactive) forms of a protein that can be
cleaved to produce an active protein at a desired time and
location. For example, a modified morphogen containing a collagen
binding domain (e.g. H2487, shown in FIG. 7A) can be delivered in
an inactive form to a desired tissue locus (e.g. a locus containing
an implanted collagen matrix) and cleaved at that locus to produce
an active morphogen. Cleavage can result from conditions endogenous
to the target locus (e.g., naturally-occurring proteases) or can be
the result of administration of specific proteases or other factors
(e.g., acidification of a locus). In addition, a very specific
protease cleavage site may be engineered, e.g., for a protease
found in a fracture site, allowing selective, delayed, and/or
gradual activation of OP-1 at the site of implant.
[0187] D. Domain Swapping
[0188] Additional constructs to alter refolding, solubility,
activity and expression can be designed by replacing the native
leader sequence of one TGF-.beta. superfamily protein with the
native leader sequence of another TGF-.beta. family member. For
example, the construct H2549 has the N-terminus of BMP-2 transposed
onto OP-1.
[0189] E. Heterodimers
[0190] Although some N-terminal fusion protein monomers as
described above do not form active homodimers without cleavage of
the leader sequence, active heterodimers are formed between those
proteins and unmodified monomers of TGF-.beta. family proteins.
Accordingly, such heterodimers can be used to provide proteins to a
target site by virtue of the N-terminal non-TGF-.beta. family
protein domain attached to the fusion protein, such as a collagen
binding domain. Alternatively, design features can be used to
enhance purification of heterodimers. Purification can be
facilitated by accentuating purification differences between two
kinds of subunits, for instance, by adding a hexa-histidine. A
mixed refolding would provide a mixture of two homodimers and the
heterodimer, which provides three separable species. For example,
an N-terminal fusion protein containing a hexa-histidine domain
(e.g. H2440, shown in FIG. 7B) which binds an IMAC column, is
useful to aid in purification of the fusion protein, which can
subsequently be activated by cleavage of the N-terminal domain.
[0191] E. coli expression for construction of heterodimers of the
present invention is preferred, because the practitioner can adjust
the ratio of each monomer for optimal yields of heterodimer. In
addition, this method is very rapid. For example, in an in vitro
heterodimer formation experiment between the hexa-histidine tagged
OP-1, modified with the preferred modifications of charged amino
acids, E, D, E, and R, (H2440) (see, for example, Attorney Docket
No. ______, the entire disclosure of which is incorporated by
reference herein) and BMP-2, the yield of heterodimers were
excellent. There is an exceptionally high yield of heterodimer,
more than the theoretically expected 50% heterodimer and 25% of
each homodimer. This may occur because BMP-2 associates more
readily with OP-1 than with itself, or faster than OP-1
reassociates with itself. Alternatively, the BMP-2 may act as
chaperone for folding. Another experiment also showed heterodimer
formation between BMP-2 and the H2447 mutant, OP-1 (no hexa-his
tag), which also associated readily, generating good yields of
heterodimer. Heterodimers were also made between FB-OP-1 (H2521)
and BMP-2. Heterodimers of truncated OP-1, H2469 (retaining 15
residues upstream of the first cysteine), and BMP-5 (H2475); and
H2469 and CDMP-2 (H2471) have also been constructed.
[0192] As well as being efficient in refolding, heterodimers of
hexa-his-OP-1 (H2440) and BMP-2 (H2142) have much greater activity
in a ROS assay than the homodimers. The hexa-his-OP-1 homodimer had
very low activity. The homodimer of BMP-2 had better activity.
However, OP-1/BMP-2 heterodimer was far more active than either
parent homodimer. In this assay the heterodimer had only about
3-fold less activity than the CHO derived OP-1 standard. The
heterodimer of OP-1 without the hexa-his tag, (H2447) with BMP-2
had similar activity. H2447 is a refolding mutant with
modifications in finger-2 and had relatively lower activity as a
homodimer. Heterodimers of OP-1 (H2469)/BMP-5 (H2475) and OP-1
(H2469)/CDMP-2 (H2471) provided a good result on a ROS assay
(2.5-3+).
[0193] Using this same protocol and methodology, an OP-1/BMP-2
heterodimer was constructed, expressed in E. coli, and refolded in
vitro. Specifically, H2447/BMP-2 heterodimers and H2440/BMP-2
heterodimers were created by E. coli expression and refolded in
vitro under physiological conditions. Based on SDS-PAGE analysis,
most of the material readily combined to form a heterodimeric
species. Additional species are formed using heterodimers
comprising a non-morphogen domain. Examples of such species are
N-terminal fused to morphogens, such as collagen binding domain
fused to OP-1 (H2487), hexa-histidine fused to OP-1 (H2440), and FB
domain of Protein A fused to OP-1 (H2521), and FB-domain fused to
the hexa-histidine/OP-1 construct H2440 (H2525).
[0194] Active heterodimers can also be constructed from two BMPs or
other TGF-.beta. family proteins that were expressed in different
systems. Some constructs are expressed better and are more active
when expressed in certain systems over others. One can express each
construct in the environment best suited for its expression and
then form active heterodimers with them. For example, H2223, a
mutant OP-1, is expressed in CHO cells, a mammalian expression
system, while H2525 (FIG. 7D), FB-domain OP-1, is best expressed in
E. coli, a bacterial expression system.
[0195] Further, the activity of the heterodimers can be manipulated
by changing the two proteins used. For example, a heterodimer of
H2487, OP-1 with a decapeptide collagen binding site, and CDMP3 can
be formed. This heterodimer will have an activity different from a
H2487 and BMP-2 heterodimer.
[0196] F. Choice and Optimization of Constructs
[0197] As taught herein, the present invention provides the skilled
artisan with the know-how to craft customized chimeric proteins and
DNAs encoding the same. Further taught and exemplified herein are
the means to design chimeric proteins having certain desired
attribute(s) making them suitable for specific in vivo applications
(see at least Sections I.B., II., and III. Examples 1-4, 8 and 11
for exemplary embodiments of the foregoing chimeric proteins). For
example, chimeric proteins having altered solubility attributes can
be used in vivo to manipulate morphogenic effective amounts
provided to a recipient. That is, increased solubility can result
in increased availability; diminished solubility can result in
decreased availability. Thus, such systemically administered
chimeric proteins can be immediately available/have immediate
morphogenic effects, whereas locally administered chimeric proteins
can be available more slowly/have prolonged morphogenic effects.
The skilled artisan will appreciate when increased versus
diminished solubility attributes are preferred given the facts and
circumstances at hand. Optimization of such parameters requires
routine experimentation and ordinary skill.
[0198] Similarly, chimeric proteins having altered stability
attributes can be used in vivo to manipulate morphogenic effective
amounts provided to a recipient. That is, increased stability can
result in increased half-life because turnover in vivo is less;
diminished stability can result in decreased half-life and
availability because turnover in vivo is more. Thus, such
systemically administered chimeric proteins can either be
immediately available/have immediate morphogenic effects achieving
a bolus-type dosage or can be available in vivo for prolonged
periods/have prolonged morphogenic effects achieving a sustained
release type dosage. The skilled artisan will appreciate when
increased versus diminished stability attributes are preferred
given the facts and circumstances at hand. Optimization of such
parameters requires routine experimentation and ordinary skill.
[0199] In addition, those protein constructs with altered stability
can also be used to practical advantage for improving shelf-life,
storage and/or shipping considerations. Furthermore, on a related
matter, altered stability can also directly affect dosage
considerations thereby, for example, reducing the cost of
treatment.
[0200] Additionally, chimeric proteins having a combination of
altered attributes, such as but not limited to solubility and
stability attributes, can be used in vivo to manipulate morphogenic
effective amounts provided to a recipient. That is, by designing a
chimeric protein with a combination of specific altered attributes,
morphogenic effective amounts can be administered in a
timed-release fashion; dosages can be regulated both in terms of
amount and duration; treatment regimens can be initiated at low
doses systemically or locally followed by a transition to high
doses, or vice versa; to name but a few paradigms. The skilled
artisan will appreciate when low versus high morphogenic effective
amounts are suitable under the facts and circumstances at hand.
Optimization of such parameters requires routine experimentation
and ordinary skill.
[0201] Furthermore, chimeric proteins having one or more altered
attributes are useful to overcome inherent deficiencies in
development. Chimeric proteins having one or more altered
attributes can be designed to circumvent an inherent defect in a
host's native morphogenic signaling system. As a non-limiting
example, a chimeric protein of the present invention can be used to
bypass a defect in a native receptor in a target tissue, a defect
in an intracellular signaling pathway, and/or a defect in other
events which are reliant on the attributes of a subdomain(s)
associated with recognition of a moiety per se as opposed to the
attributes associated with function/biological activity which are
embodied in a different subdomain(s). The skilled artisan will
appreciate when such chimeric proteins are suitable given the facts
and circumstances at hand. Optimization requires routine
experimentation and ordinary skill.
[0202] Practice of the invention will be still more fully
understood from the following examples, which are presented herein
for illustration only and should not be construed as limiting the
invention in any way.
EXAMPLE 1
Synthesis of a BMP Mutant
[0203] FIG. 8 shows the nucleotide and corresponding amino acid
sequence for the OP-1 C-terminal seven cysteine domain. Knowing
these sequences permits identification of useful restriction sites
for engineering in mutations by, for example, cassette mutagenesis
or the well-known method of Kunkel (mutagenesis by primer extension
using m13-derived single-stranded templates) or by the well-known
PCR methods, including overlap extension. An exemplary mutant of
OP-1 is H2460, with 4 amino acid changes in the finger 2 sub-domain
and an amino acid change in the last C-terminal amino acid,
constructed as described below. It is understood by the skilled
artisan that the mutagenesis protocol described is exemplary only,
and that other means for creating the constructs of the invention
are well-known and well described in the art.
[0204] Four amino acid changes were introduced into the OP-1 finger
2 sub-domain sequence by means of standard polymerase chain
reactions using overlap extension technique, resulting in OP-1
mutant H2460. The four changes in the finger 2 region were N6>S,
R25>E, N26>D and R30>E. This mutant also contained a
further change, H35>R, of the C-terminal residue. The template
for these reactions was the mature domain of a wild type OP-1 cDNA
clone, which had been inserted into an E. coli expression vector
engineered with an ATG start codon at the beginning of the mature
region. The ATG had been introduced by PCR using as a forward
primer a synthetic oligonucleotide of the following sequence: ATG
TCC ACG GGG AGC AAA CAG (SEQ ID NO: 36), encoding M S T G S K Q
(SEQ ID NO: 37). The PCR reaction was done in combination with an
appropriate back-primer complementary to the 3' coding region of
the cDNA.
[0205] In order to construct the finger 2 mutant H2460, a PCR
fragment encoding the modified finger-2 was made in a standard PCR
reaction, using a commercially available PCR kit and following the
manufacturer's instructions using as primers synthetic
oligonucleotides.
[0206] To obtain the N6>S change, a forward primer (primer #1)
of the sequence GCG CCC ACG CAG CTC AGC GCT ATC TCC GTC CTC (SEQ ID
NO: 70) was used, encoding the amino acid sequence: A P T Q L S A I
S V L (SEQ ID NO: 71).
[0207] For the changes near the C-terminus, a back-primer, 43
nucleotides long, (primer #2) was used which introduced the
R25>E and N26>D and R30>E and C-terminal H35>R changes.
This primer #2 had the sequence: CTA TCT GCA GCC ACA AGC TTC GAC
CAC CAT GTC TTC GTA TTT C (SEQ ID NO: 72) which is the complement
of the coding sequence, G AAA TAC GAA GAC ATG GTG GTC GAA GCT TGT
GGC TGC AGA TAG (SEQ ID NO: 73) encoding the amino acids: K Y E D M
V V E A C G C R stop (SEQ ID NO: 74).
[0208] The fragment with finger 2 and C-terminus mutations was then
combined with another PCR fragment encoding the upstream part of
mature OP-1, with N-terminus, finger-1 and heel sub-domains. The
latter PCR fragment, encoding the N-terminus, finger 1 and heel
sub-domains was constructed again using an OP-1 expression vector
for E. coli as template. The vector contained an OP-1 cDNA
fragment, encoding the mature OP-1 protein attached to a T7
promoter and ribosome binding site for expression under control of
either a T7 promoter in an appropriate host or under control of a
trp promoter. In this T7 expression vector, Pet 3d (Novagen Inc.,
Madison Wis.) the sequence between the T7 promoter, at the XbaI
site, and the ATG codon of mature OP-1 is as follows:
TCTAGAATAATTTTGTTTAACCTTTAAGAAGGAGATATACG ATG (SEQ ID NO: 75).
[0209] This second PCR reaction was primed with a forward primer
(primer #3) TAA TAC GAC TCA CTA TAG G (SEQ ID NO: 76) which primes
in the T7 promoter region and a back-primer (primer #4) that
overlaps with primer #1 and has the nucleotide sequence GCT GAG CTG
CGT GGG CGC (SEQ ID NO: 77), which is the complement of the coding
sequence GCG CCC ACG CAG CTC AGC (SEQ ID NO: 78), encoding A P T Q
L S (SEQ ID NO:79).
[0210] In a third PCR reaction, the actual overlap extension
reaction, portions of the above two PCR fragments were combined and
amplified by PCR, resulting in a single fragment containing the
complete mature OP-1 region. For this reaction, primer #3 was used
as forward primer and a new primer (primer #5) was used as a
back-primer with the following sequence GG ATC CTA TCT GCA GCC ACA
AGC (SEQ ID NO: 80), which is the complement to coding sequence GCT
TGT GGC TGC AGA TAG GAT CC (SEQ ID NO: 81), encoding A C G C R stop
(SEQ ID NO: 82). This primer also adds a convenient 3' BamHI site
for of inserting the gene into the expression vector.
[0211] The resulting fragment bearing the complete mutant gene,
resulting from the overlap extension PCR, was cloned into a
commercial cloning vector designed for cloning of PCR fragments,
such as pCR2.1-topo-TA (Invitrogen Inc., Carlsbad Calif.). The
cloned PCR fragment was recovered by restriction digest with XbaI
and BamHI and inserted into the XbaI and BamHI sites of a
commercially available T7 expression vector such as Pet3d (Novagen
Inc., Madison Wis.).
EXAMPLE 2
E. coli Expression of a BMP
[0212] Transformed cells were grown in standard SPYE 2YT media, 1:1
ratio, (see, Sambrook et al., for example) at 37.degree. C., under
standard culturing conditions. Heterologous protein overexpression
typically produced inclusion bodies within 8-48 hours. Inclusion
bodies were isolated and solubilized as follows. One liter of
culture fluid was centrifuged to collect the cells. The cells in
the resulting pellet then were resuspended in 60 ml 25 mM Tris, 10
mM EDTA, pH 8.0 (TE Buffer)+100 .mu.g/ml lysozyme and incubated at
37.degree. C. for 2 hours. The cell suspension was then chilled on
ice and sonicated to lyse the cells. Cell lysis was ascertained by
microscopic examination. The volume of the lysate was adjusted to
approximately 300 ml with TE Buffer, then centrifuged to obtain an
inclusion body pellet. The pellet was washed by 2-4 successive
resuspensions in TE Buffer and centrifugation. The washed inclusion
body pellet was solubilized by denaturation and reduction in 40 ml
100 mM Tris, 10 mM EDTA, 6M GuHCl (guanidinium hydrochloride), 250
mM DTT, pH 8.8. Proteins then were pre-purified using a standard,
commercially available C2 or C8 cartridge (SPICE cartridges, 400
mg, Ananltech, Inc.). Protein solutions were acidified with 2% TFA
(trifluoroacetic acid), applied to the cartridge, washed with 0.1%
TFA/10% acetonitrile, and eluted with 0.1% TFA/70% acetonitrile.
The eluted material then was dried down or diluted and fractionated
by C4 RP-HPLC.
EXAMPLE 3
Refolding of a BMP Dimer
[0213] Proteins prepared as described above were dried down prior
to refolding, or diluted directly into refolding buffer. The
preferred refolding buffer used was: 100 mM Tris, 10 mM EDTA, 1 M
NaCl, 2% CHAPS, 5 mM GSH (reduced glutathione), 2.5 mM GSSG
(oxidized glutathione), pH 8.5. Refoldings (12.5-200 .mu.g
protein/ml) were carried out at 4.degree. C. for 24-90 hours,
typically 36-48 hours, although longer than this (up to weeks) are
expected to provide good refolding in some mutants, followed by
dialysis against 0.1% TFA, then 0.01% TFA, 50% ethanol. Aliquots of
the dialyzed material then was dried down in preparation for the
various assays.
EXAMPLE 4
Purification and Testing of a Refolded BMP Dimer
[0214] 4A. SDS-PAGE, HPLC--Samples were dried down and resuspended
in Laemmli gel sample buffer and then electrophoresed in a 15%
SDS-polyacrylamide gel. All assays included molecular weight
standards and/or purified mammalian cell produced OP-1 for
comparison. Analysis of OP-1 dimers was performed in the absence of
added reducing agents, while OP-1 monomers were produced by the
addition of 100 mM DTT to the gel samples. Folded dimer has an
apparent molecular weight in the range of about 30-36 kDa, while
monomeric species have an apparent molecular weight of about 14-16
kDa.
[0215] Alternatively, samples were chromatographed on a
commercially available RP-HPLC, as follows. Samples were dried down
and resuspended in 0.1% TFA/30% acetonitrile. The protein then was
applied to a C18 column in 0.1% TFA, 30% acetonitrile and
fractionated using a 30-60% acetonitrile gradient in TFA. Properly
folded dimers elute as a discrete peak at 45-50% acetonitrile;
monomers elute at 50-60% acetonitrile.
[0216] 4B. Hydroxyapatite Chromatography--Samples were loaded onto
hydroxyapatite in 10 mM phosphate, 6 M urea, pH 7.0 (Column
Buffer). Unbound material was removed by washing with column
buffer, followed by elution of monomer with Column Buffer+100 mM
NaCl. Dimers were eluted with Column Buffer+250 mM NaCl.
[0217] 4C. Trypsin Digest--Tryptic digests were performed in a
digestion buffer of 50 mM Tris, 4 M urea, 100 mM NaCl, 0.3% Tween
80, 20 mM methylamine, pH 8.0. The ratio of enzyme to substrate was
1:50 (weight to weight). After incubation at 37.degree. C. for 16
hours, 15 .mu.l of digestion mixture was combined with 5 .mu.l
4.times. gel sample buffer without DTT and analyzed by SDS-PAGE.
Purified mammalian OP-1 and undigested BMP dimer were included for
comparison. Under these conditions, properly folded dimers are
cleaved to produce a species with slightly faster migration than
uncleaved standards, while monomers and mis-folded dimers are
completely digested and do not appear as bands in the stained
gel.
EXAMPLE 5
In Vitro Cell-Based Bioassay of Osteogenic Activity
[0218] This example demonstrates the bioactivity of morphogen
constructs which have acquired osteogenic or bone-forming
capabilities in accordance with the present invention. Osteogenic
proteins having either an inuate ability or an acquired ability for
high specific bone forming activity can induce alkaline phosphatase
activity in rat osteoblasts, including rat osteosarcoma cells and
rat calveria cells. In the assay rat osteosarcoma or calveria cells
were plated onto a multi-well plate (e.g., a 48 well plate) at a
concentration of 50,000 osteoblasts per well, in .alpha.MEM
(modified Eagle's medium, Gibco, Inc. Long Island) containing 10%
FBS (fetal bovine serum), L-glutamine and penicillin/streptomycin.
The cells were incubated for 24 hours at 37.degree. C., at which
time the growth medium was replaced with a MEM containing 1% FBS
and the cells incubated for an additional 24 hours so that cells
were in serum-deprived growth medium at the time of the
experiment.
[0219] Cultured cells then were divided into three groups: (1)
wells receiving various concentrations of biosynthetic ostegenic
protein; (2) a positive control, such as mammalian expressed hOP-1;
and a negative control (no protein or TGF-.beta.). The protein
concentrations tested were in the range of 50-500 ng/ml. Cells were
incubated for 72 hours. After the incubation period the cell layer
was extracted with 0.5 ml of 1% TritonX-100. The resultant cell
extract was centrifuged, 100 .mu.l of the extract was added to 90
.mu.l of PNPP (paranitrosophenylphosphate)/gl- ycerine mixture and
incubated for 30 minutes in a 37.degree. C. water bath and the
reaction stopped with 100 .mu.l 0.2N NaOH. The samples then were
run through a plate reader (e.g., Dynatech MR700) and absorbance
measured at 400 nm, using p-nitrophenol as a standard, to determine
the presence and amount of alkaline phosphatase activity. Protein
concentrations were determined by standard means, e.g., the Biorad
method, UV scan or HPLC area at 214 nm. Alkaline phosphatase
activity was calculated in units/.mu.g protein, where 1 unit equals
1 nmol p-nitrophenol liberated/30 minutes at 37.degree. C.
[0220] HOP-1 and BMP2 generate approximately 1.0-1.4 units at
between 100-200 ng/ml. Other results are provided in Table 1 for
the various protein constructs.
EXAMPLE 6
In Vitro Cell-Based Bioassay of CDMP Activity
[0221] This example demonstrates the bioactivity of constructs
which have acquired enhanced tissue morphogenic capabilities in
accordance with the present invention. Native CDMPs fail to induce
alkaline phosphatase activity in rat osteosarcoma cells as used in
Example 5, but they do induce alkaline phosphatase activity in the
mouse teratocarcinoma cell line ATDC-5, a chondroprogenitor cell
line (Atsumi, et al., 1990, Cell Differentiation and Development
30: 109). Folded mutants that are negative in the rat
osteocarcinoma cell assay but positive in the ATDC-5 assay are
described as having acquired CDMP-like activity. In the ATDC-5
assay, cells were plated at density of 4.times.10.sup.4 in
serum-free basal medium (BM: Ham's F-12/DMEM [1:1] with
ITS.TM.+culture supplement [Collaborative Biomedical Products,
Bedford, Mass.], alpha-ketoglutarate (1.times.10.sup.-4 M),
ceruloplasmin (0.25 U/ml), cholesterol (5 .mu.g/ml),
phosphatidylethanolamine (2 .mu.g/ml), alpha-tocopherol acid
succinate (9.times.10.sup.-7 M), reduced glutathione (10 .mu.g/ml),
taurine (1.25 .mu.g/ml), triiodothyronin (1.6.times.10.sup.-9 M),
parathyroid hormone (5.times.10.sup.-10 M), .beta.-glycerophosphate
(10 mM), and L-ascorbic acid 2-sulphate (50 .mu.g/ml)). CDMP or
other biosynthetic osteogenic protein (0-300 ng/ml) was added the
next day and the culture medium, including CDMP or biosynthetic
osteogenic protein, replaced every other day. Alkaline phosphatase
activity was determined in sonicated cell homogenates after 4, 6
and/or 12 days of treatment. After extensive washing with PBS, cell
layers were sonicated in 500 .mu.l of PBS containing 0.05%
Triton-X100. 50-100 .mu.l aliquots were assayed for enzyme activity
in assay buffer (0.1M sodium barbital buffer, pH 9.3) and
p-nitrophenyl phosphate as substrate. Absorbance was measured at
400 nm, and activity normalized to protein content measured by
Bradford protein assay (bovine serum albumin standard).
[0222] CDMP-1 and CDMP-2 generated approximately 2-3 units of
activity at day 10 at 100 ng/ml. OP-1 generated approximately 6-7
units of activity at day 10 at 100 ng/ml.
EXAMPLE 7
In Vitro Cell-Based Bioassay of TGF-.beta.-Like Activity
[0223] This example demonstrates the bioactivity of biosynthetic
mutant TGF-.beta. proteins having altered biological capabilities
in accordance with the invention. TGF-.beta. proteins can inhibit
epithelial cell proliferation. Numerous cell inhibition assays are
well described in the art. See, for example, Brown, et. al. (1987)
J. Immunol. 139:2977, describing a colorimetric assay using human
melanoma A375 fibroblast cells, and described herein below. Another
assay uses epithelial cells, e.g., mink lung epithelial cells, and
proliferative effects are determined by .sup.3H-thymidine
uptake.
[0224] Briefly, in the assay the TGF-.beta. biosynthetic construct
is serially diluted in a multi-well tissue plate containing
RPMI-1640 medium (Gibco) and 5% fetal calf serum. Control wells
receive medium only. Melanoma cells then are added to the well
(1.5.times.10.sup.4). The plates then are incubated at 37.degree.
C. for about 72 hours in 5% CO.sub.2, and the cell monolayers
washed once, fixed and stained with crystalviolet for 15 minutes.
Unbound stain is washed out and the stained cells then lysed with
33% acetic acid to release the stain (confined to the cell nuclei),
and the OD measured at 590 nm with a standard, commercially
available photometer to calculate the activity of the test
molecules. The intensity of staining in each well is directly
related to the number of nuclei. Accordingly, active TGF-.beta.
molecules are expected to stain lighter than inactive compounds or
the negative control well.
[0225] In another assay, mink lung cells are used. These cells grow
and proliferate under standard culturing conditions, but are
arrested following exposure to TGF-.beta., as determined by
.sup.3H-thymidine uptake using culture cells from a mink lung
epithelial cell line (ATTC No. CCL 64, Rockville, Md.). Briefly
cells are grown to confluency with in EMEM, supplemented with 10%
FBS, 200 units/ml penicillin, and 200 .mu.g/ml streptomycin. These
cells are cultured to a cell density of about 200,000 cells per
well. At confluency the media is replaced with 0.5 ml of EMEM
containing 1% FBS and penicillin/streptomycin and the culture
incubated for 24 hours at 37.degree. C. Candidate proteins then are
added to each well and the cells incubated for 18 hours at
37.degree. C. After incubation, 1.0 .mu.Ci of .sup.3H-thymidine in
10 .mu.l was added to each well, and the cells incubated for four
hours at 37.degree. C. The media then is removed from each well and
the cells washed once with ice-cold phosphate buffered saline and
DNA precipitated by adding 0.5 ml of 10% TCA to each well and
incubated at room temperature for 15 minutes. The cells are washed
three times with ice-cold distilled water, lysed with 0.5 ml 0.4 M
NaOH, and the lysate from each well then transferred to a
scintillation vial and the radioactivity recorded using a
scintillation counter (Smith-Kline Beckman). Biologically active
molecules will inhibit cell proliferation resulting in less
thymidine uptake and fewer counts as compared to inactive proteins
and/or the negative control well (no added growth factor).
EXAMPLE 8
In Vivo Bioassay of Osteogenic Activity: Endochondral Bone
Formation and Related Properties
[0226] The art-recognized bioassay for bone induction as described
by Sampath and Reddi (Proc. Natl. Acad. Sci. USA (1983)
80:6591-6595) and U.S. Pat. Nos. 4,968,590, 5,266,683, the
disclosures of which is herein incorporated by reference, can be
used to establish the efficacy of a given protein, device or
formulation. Briefly, the assay consists of depositing test samples
in subcutaneous sites in recipient rats under ether anesthesia. A
vertical incision (1 cm) is made under sterile conditions in the
skin over the thoracic region, and a pocket is prepared by blunt
dissection. In certain cases, the desired amount of osteogenic
protein (10 ng-10 .mu.g) is mixed with approximately 25 mg of
matrix material, prepared using standard procedures such as
lyophilization, and the test sample is implanted deep into the
pocket and the incision is closed with a metallic skin clip. The
heterotropic site allows for the study of bone induction without
the possible ambiguities resulting from the use of orthotopic
sites. The implants also can be provided intramuscularly which
places the devices in closer contact with accessable progenitor
cells. Typically intramuscular implants are made in the skeletal
muscle of both legs.
[0227] The sequential cellular reactions occurring at the
heterotropic site are complex. The multistep cascade of
endochondral bone formation includes: binding of fibrin and
fibronectin to implanted matrix, chemotaxis of cells, proliferation
of fibroblasts, differentiation into chondroblasts, cartilage
formation, vascular invasion, bone formation, remodeling, and bone
marrow differentiation.
[0228] Successful implants exhibit a controlled progression through
the stages of protein-induced endochondral bone development
including: (1) transient infiltration by polymorphonuclear
leukocytes on day one; (2) mesenchymal cell migration and
proliferation on days two and three; (3) chondrocyte appearance on
days five and six; (4) cartilage matrix formation on day seven; (5)
cartilage calcification on day eight; (6) vascular invasion,
appearance of osteoblasts, and formation of new bone on days nine
and ten; (7) appearance of osteoblastic and bone remodeling on days
twelve to eighteen; and (8) hematopoietic bone marrow
differentiation in the ossicle on day twenty-one.
[0229] Histological sectioning and staining is preferred to
determine the extent of osteogenesis in the implants. Staining with
toluidine blue or hemotoxylin/eosin clearly demonstrates the
ultimate development of endochondral bone. Twelve day bioassays are
sufficient to determine whether bone inducing activity is
associated with the test sample.
[0230] Additionally, alkaline phosphatase activity and/or total
calcium content can be used as biochemical markers for
osteogenesis. The alkaline phosphatase enzyme activity can be
determined spectrophotometrically after homogenization of the
excised test material. The activity peaks at 9-10 days in vivo and
thereafter slowly declines. Samples showing no bone development by
histology should have no alkaline phosphatase activity under these
assay conditions. The assay is useful for quantitation and
obtaining an estimate of bone formation very quickly after the test
samples are removed from the rat. The results as measured by
alkaline phosphatase activity level and histological evaluation can
be represented as "bone forming units". One bone forming unit
represents the amount of protein that is needed for half maximal
bone forming activity on day 12. Additionally, dose curves can be
constructed for bone inducing activity in vivo at each step of a
purification scheme by assaying various concentrations of protein.
Accordingly, the skilled artisan can construct representative dose
curves using only routine experimentation.
[0231] Total calcium content can be determined after homogenization
in, for example, cold 0.15M NaCl, 3 mM NaHCO.sub.3, pH 9.0, and
measuring the calcium content of the acid soluble fraction of
sediment.
EXAMPLE 9
Activity of "Domain Swapping" Mutant
[0232] Domain swapping occurs, for example, when one takes the
N-terminal region of one type of TGF-.beta. family member protein
and attaches it to the seven cysteine domain of another type of
TGF-.beta. family member protein. A mutant construct was created by
splicing the sequence of the BMP-2 terminus onto the seven cysteine
active domain of OP-1 using routine techniques generally known to
those of ordinary skill in the art. The resulting mutant, H2549,
has an N-terminal region consisting of MQAKHKQRKRLKSS-C. The last
amino acid, cysteine, is the first cysteine of the seven cysteine
active domain of OP-1. A ROS assay, as described above in Example
5, was used to test activity of H2549.
[0233] As illustrated in FIG. 11, the results show that H2549 has
very low activity as compared to the level of activity of OP-1.
However, upon trypsin cleavage of H2549, using a method similar to
trypsin cleavage of dimers described in Example 4, ROS activity is
significantly increased. In this manner, the activity of TGF-.beta.
family member proteins can be selectively controlled by attaching
non-native N-terminal sequences to inactivate it and cleaving the
non-native sequences to activate it.
EXAMPLE 10
N-Terminal Truncations Increase Activity
[0234] Truncations at the N-terminal regions of modified morphogen
proteins, for example by trypsin cleavage, increase ROS activity.
Construct H2223 is a modified OP-1 mutant expressed in CHO cells.
Two HPLC fractions of H2223 were collected, fractions 13 and 14. An
amount of each fraction was truncated by trypsin cleavage, in a
manner similar to that used upon dimers in Example 4. The four
resulting samples, i.e., fractions 13 and 14 untreated with trypsin
and fractions 13 and 14 treated with trypsin, were then subjected
to a ROS assay, as described in Example 5 above, using OP-1
activity as the standard.
[0235] As illustrated in FIG. 12, the activity level of fractions
14 treated and untreated with trypsin are relatively the same. This
is explained by fraction 14 being composed of partially truncated
H2223 and, thus, further truncation with trypsin does not alter
activity. In contrast, untreated fraction 13 is composed of mainly
full length H2223 (i.e., the entire N-terminus of 39 amino acids)
and truncation of the N-terminus of fraction 13 does increase ROS
activity to levels comparable to those of fraction 14. These
activity levels are well above the ROS activity level of the OP-1
standard, and demonstrate that improvements in activity obtained
with the modified proteins of the present invention.
EXAMPLE 11
Heterodimer Activity
[0236] Activity levels of heterodimers are higher than those of the
homodimers formed from each of the respective subunits of the
heterodimer. Construct H2440, OP-1 with a hexa-his N-terminus, and
H2142, BMP-2, were allowed to form heterodimers and homodimers
using the method as described in Example 3 above. Heterodimers of
H2440/2142, and homodimers of H2440/2440 and H2142/2142 were then
subjected to a ROS assay, as described in Examples 4 and 5
above.
[0237] As shown in FIGS. 13A and 13B, the homodimers of H2440, OP-1
with a hexa-his at the N-terminal have very low activity. The
homodimers of H2142, BMP-2, have better activity, but activity is
still relatively low. However, the heterodimer, OP-1 hexa-his and
BMP-2, have far greater activity than either of the homodimers. The
heterodimers have only 3-fold less activity than the CHO derived
OP-1.
[0238] In a similar experiment, homodimers and heterodimers were
created between H2525, OP-1 with FB leader sequence, and H2142,
BMP-2. These were also subjected to a ROS assay with the level of
OP-1 activity as the standard. As illustrated in FIG. 14,
homodimers of H2525, OP-1 with FB, have virtually no activity and
homodimers of H2142, BMP-2, have very low activity. In contrast,
heterodimers of the two, H2525/2142, have unexpectedly high
activity levels.
Sequence CWU 1
1
124 1 35 PRT Drosophila melanogaster 60-A 1 Ala Pro Thr Arg Leu Gly
Ala Leu Pro Val Leu Tyr His Leu Asn Asp 1 5 10 15 Glu Asn Val Asn
Leu Lys Lys Tyr Arg Asn Met Ile Val Lys Ser Cys 20 25 30 Gly Cys
His 35 2 35 PRT Homo sapiens BMP-2 2 Val Pro Thr Glu Leu Ser Ala
Ile Ser Met Leu Tyr Leu Asp Glu Asn 1 5 10 15 Glu Lys Val Val Leu
Lys Asn Tyr Gln Asp Met Val Val Glu Gly Cys 20 25 30 Gly Cys Arg 35
3 35 PRT Homo sapiens BMP-3 3 Val Pro Glu Lys Met Ser Ser Leu Ser
Ile Leu Phe Phe Asp Glu Asn 1 5 10 15 Lys Asn Val Val Leu Lys Val
Tyr Pro Asn Met Thr Val Glu Ser Cys 20 25 30 Ala Cys Arg 35 4 35
PRT Homo sapiens BMP-4 4 Val Pro Thr Glu Leu Ser Ala Ile Ser Met
Leu Tyr Leu Asp Glu Tyr 1 5 10 15 Asp Lys Val Val Leu Lys Asn Tyr
Gln Glu Met Val Val Glu Gly Cys 20 25 30 Gly Cys Arg 35 5 35 PRT
Homo sapiens BMP-5 5 Ala Pro Thr Lys Leu Asn Ala Ile Ser Val Leu
Tyr Phe Asp Asp Ser 1 5 10 15 Ser Asn Val Ile Leu Lys Lys Tyr Arg
Asn Met Val Val Arg Ser Cys 20 25 30 Gly Cys His 35 6 35 PRT Homo
sapiens BMP-6 6 Ala Pro Thr Lys Leu Asn Ala Ile Ser Val Leu Tyr Phe
Asp Asp Asn 1 5 10 15 Ser Asn Val Ile Leu Lys Lys Tyr Arg Asn Met
Val Val Arg Ala Cys 20 25 30 Gly Cys His 35 7 36 PRT Homo sapiens
BMP-9 7 Val Pro Thr Lys Leu Ser Pro Ile Ser Val Leu Tyr Lys Asp Asp
Met 1 5 10 15 Gly Val Pro Thr Leu Lys Tyr His Tyr Glu Gly Met Ser
Val Ala Glu 20 25 30 Cys Gly Cys Arg 35 8 35 PRT Homo sapiens
BMP-10 8 Val Pro Thr Lys Leu Glu Pro Ile Ser Ile Leu Tyr Leu Asp
Lys Gly 1 5 10 15 Val Val Thr Tyr Lys Phe Lys Tyr Glu Gly Met Ala
Val Ser Glu Cys 20 25 30 Gly Cys Arg 35 9 35 PRT Homo sapiens
BMP-11 9 Thr Pro Thr Lys Met Ser Pro Ile Asn Met Leu Tyr Phe Asn
Asp Lys 1 5 10 15 Gln Gln Ile Ile Tyr Gly Lys Ile Pro Gly Met Val
Val Asp Arg Cys 20 25 30 Gly Cys Ser 35 10 35 PRT Bos taurus CDMP-2
10 Val Pro Thr Lys Leu Thr Pro Ile Ser Ile Leu Tyr Ile Asp Ala Gly
1 5 10 15 Asn Asn Val Val Tyr Asn Glu Tyr Glu Glu Met Val Val Glu
Ser Cys 20 25 30 Gly Cys Arg 35 11 36 PRT Gallus gallus Dorsalin 11
Val Pro Thr Lys Leu Asp Ala Ile Ser Ile Leu Tyr Lys Asp Asp Ala 1 5
10 15 Gly Val Pro Thr Leu Ile Tyr Asn Tyr Glu Gly Met Lys Val Ala
Glu 20 25 30 Cys Gly Cys Arg 35 12 35 PRT Drosophila melanogaster
DPP 12 Val Pro Thr Gln Leu Asp Ser Val Ala Met Leu Tyr Leu Asn Asp
Gln 1 5 10 15 Ser Thr Val Val Leu Lys Asn Tyr Gln Glu Met Thr Val
Val Gly Cys 20 25 30 Gly Cys Arg 35 13 35 PRT Mus musculus GDF-1 13
Val Pro Glu Arg Leu Ser Pro Ile Ser Val Leu Phe Phe Asp Asn Glu 1 5
10 15 Asp Asn Val Val Leu Arg His Tyr Glu Asp Met Val Val Asp Glu
Cys 20 25 30 Gly Cys Arg 35 14 35 PRT Mus musculus GDF-3 14 Val Pro
Thr Lys Leu Ser Pro Ile Ser Met Leu Tyr Gln Asp Ser Asp 1 5 10 15
Lys Asn Val Ile Leu Arg His Tyr Glu Asp Met Val Val Asp Glu Cys 20
25 30 Gly Cys Gly 35 15 35 PRT Homo sapiens GDF-5 15 Val Pro Thr
Arg Leu Ser Pro Ile Ser Ile Leu Phe Ile Asp Ser Ala 1 5 10 15 Asn
Asn Val Val Tyr Lys Gln Tyr Glu Asp Met Val Val Glu Ser Cys 20 25
30 Gly Cys Arg 35 16 35 PRT Mus musculus GDF-6 16 Val Pro Thr Lys
Leu Thr Pro Ile Ser Ile Leu Tyr Ile Asp Ala Gly 1 5 10 15 Asn Asn
Val Val Tyr Lys Gln Tyr Glu Asp Met Val Val Glu Ser Cys 20 25 30
Gly Cys Arg 35 17 35 PRT Mus musculus GDF-7 17 Val Pro Ala Arg Leu
Ser Pro Ile Ser Ile Leu Tyr Ile Asp Ala Ala 1 5 10 15 Asn Asn Val
Val Tyr Lys Gln Tyr Glu Asp Met Val Val Glu Ala Cys 20 25 30 Gly
Cys Arg 35 18 35 PRT Mus musculus GDF-9 18 Val Pro Gly Lys Tyr Ser
Pro Leu Ser Val Leu Thr Ile Glu Pro Asp 1 5 10 15 Gly Ser Ile Ala
Tyr Lys Glu Tyr Glu Asp Met Ile Ala Thr Arg Cys 20 25 30 Thr Cys
Arg 35 19 32 PRT Homo sapiens GDNF 19 Arg Pro Ile Ala Phe Asp Asp
Asp Leu Ser Phe Leu Asp Asp Asn Leu 1 5 10 15 Val Tyr His Ile Leu
Arg Lys His Ser Ala Lys Arg Cys Gly Cys Ile 20 25 30 20 38 PRT Homo
sapiens Inhibin Alpha 20 Ala Ala Leu Pro Gly Thr Met Arg Pro Leu
His Val Arg Thr Thr Ser 1 5 10 15 Asp Gly Gly Tyr Ser Phe Lys Tyr
Glu Thr Val Pro Asn Leu Leu Thr 20 25 30 Gln His Cys Ala Cys Ile 35
21 35 PRT Homo sapiens Inhibin BetaA 21 Val Pro Thr Lys Leu Arg Pro
Met Ser Met Leu Tyr Tyr Asp Asp Gly 1 5 10 15 Gln Asn Ile Ile Lys
Lys Asp Ile Gln Asn Met Ile Val Glu Glu Cys 20 25 30 Gly Cys Ser 35
22 35 PRT Homo sapiens Inhibin BetaB 22 Ile Pro Thr Lys Leu Ser Thr
Met Ser Met Leu Tyr Phe Asp Asp Glu 1 5 10 15 Tyr Asn Ile Val Lys
Arg Asp Val Pro Asn Met Ile Val Glu Glu Cys 20 25 30 Gly Cys Ala 35
23 35 PRT Homo sapiens Inhibin BetaC 23 Val Pro Thr Ala Arg Arg Pro
Leu Ser Leu Leu Tyr Tyr Asp Arg Asp 1 5 10 15 Ser Asn Ile Val Lys
Thr Asp Ile Pro Asp Met Val Val Glu Ala Cys 20 25 30 Gly Cys Ser 35
24 34 PRT Homo sapiens MIS 24 Val Pro Thr Ala Tyr Ala Gly Lys Leu
Leu Ile Ser Leu Ser Glu Glu 1 5 10 15 Arg Ile Ser Ala His His Val
Pro Asn Met Val Ala Thr Glu Cys Gly 20 25 30 Cys Arg 25 34 PRT Mus
musculus Nodal 25 Ala Pro Val Lys Thr Lys Pro Leu Ser Met Leu Tyr
Val Asp Asn Gly 1 5 10 15 Arg Val Leu Leu Glu His His Lys Asp Met
Ile Val Glu Glu Cys Gly 20 25 30 Cys Leu 26 35 PRT Homo sapiens
OP-2 26 Ala Pro Thr Lys Leu Ser Ala Thr Ser Val Leu Tyr Tyr Asp Ser
Ser 1 5 10 15 Asn Asn Val Ile Leu Arg Lys His Arg Asn Met Val Val
Lys Ala Cys 20 25 30 Gly Cys His 35 27 35 PRT Mus musculus OP-3 27
Val Pro Thr Glu Leu Ser Ala Ile Ser Leu Leu Tyr Tyr Asp Arg Asn 1 5
10 15 Asn Asn Val Ile Leu Arg Arg Glu Arg Asn Met Val Val Gln Ala
Cys 20 25 30 Gly Cys His 35 28 35 PRT Drosophila melanogaster Screw
28 Val Pro Thr Val Leu Gly Ala Ile Thr Ile Leu Arg Tyr Leu Asn Glu
1 5 10 15 Asp Ile Ile Asp Leu Thr Lys Tyr Gln Lys Ala Val Ala Lys
Glu Cys 20 25 30 Gly Cys His 35 29 34 PRT Homo sapiens TGF-Beta1 29
Val Pro Gln Ala Leu Glu Pro Leu Pro Ile Val Tyr Tyr Val Gly Arg 1 5
10 15 Lys Pro Lys Val Glu Gln Leu Ser Asn Met Ile Val Arg Ser Cys
Lys 20 25 30 Cys Ser 30 34 PRT Homo sapiens TGF-Beta2 30 Val Ser
Gln Asp Leu Glu Pro Leu Thr Ile Leu Tyr Tyr Ile Gly Lys 1 5 10 15
Thr Pro Lys Ile Glu Gln Leu Ser Asn Met Ile Val Lys Ser Cys Lys 20
25 30 Cys Ser 31 34 PRT Homo sapiens TGF-Beta3 31 Val Pro Gln Asp
Leu Glu Pro Leu Thr Ile Leu Tyr Tyr Val Gly Arg 1 5 10 15 Thr Pro
Lys Val Glu Gln Leu Ser Asn Met Val Val Lys Ser Cys Lys 20 25 30
Cys Ser 32 34 PRT Gallus gallus TGF-Beta4 32 Val Pro Gln Thr Leu
Asp Pro Leu Pro Ile Ile Tyr Tyr Val Gly Arg 1 5 10 15 Asn Val Arg
Val Glu Gln Leu Ser Asn Met Val Val Arg Ala Cys Lys 20 25 30 Cys
Ser 33 34 PRT Xenopus laevis TGF-Beta5 33 Val Pro Asp Val Leu Glu
Pro Leu Pro Ile Ile Tyr Tyr Val Gly Arg 1 5 10 15 Thr Ala Lys Val
Glu Gln Leu Ser Asn Met Val Val Arg Ser Cys Asn 20 25 30 Cys Ser 34
35 PRT Strongylocentrotus purpuratus UNIVIN 34 Ala Pro Thr Lys Leu
Ser Gly Ile Ser Met Leu Tyr Phe Asp Asn Asn 1 5 10 15 Glu Asn Val
Val Leu Arg Gln Tyr Glu Asp Met Val Val Glu Ala Cys 20 25 30 Gly
Cys Arg 35 35 35 PRT Xenopus laevis VG-1 35 Val Pro Thr Lys Met Ser
Pro Ile Ser Met Leu Phe Tyr Asp Asn Asn 1 5 10 15 Asp Asn Val Val
Leu Arg His Tyr Glu Asn Met Ala Val Asp Glu Cys 20 25 30 Gly Cys
Arg 35 36 21 DNA Artificial Sequence Description of Artificial
Sequencesynthetic primer 36 atg tcc acg ggg agc aaa cag 21 Met Ser
Thr Gly Ser Lys Gln 1 5 37 7 PRT Artificial Sequence Description of
Artificial Sequence amino acids encoded by synthetic primer 37 Met
Ser Thr Gly Ser Lys Gln 1 5 38 1822 DNA Homo sapiens CDS
(49)..(1341) Morphogenic Protein OP1 38 ggtgcgggcc cggagcccgg
agcccgggta gcgcgtagag ccggcgcg atg cac gtg 57 Met His Val 1 cgc tca
ctg cga gct gcg gcg ccg cac agc ttc gtg gcg ctc tgg gca 105 Arg Ser
Leu Arg Ala Ala Ala Pro His Ser Phe Val Ala Leu Trp Ala 5 10 15 ccc
ctg ttc ctg ctg cgc tcc gcc ctg gcc gac ttc agc ctg gac aac 153 Pro
Leu Phe Leu Leu Arg Ser Ala Leu Ala Asp Phe Ser Leu Asp Asn 20 25
30 35 gag gtg cac tcg agc ttc atc cac cgg cgc ctc cgc agc cag gag
cgg 201 Glu Val His Ser Ser Phe Ile His Arg Arg Leu Arg Ser Gln Glu
Arg 40 45 50 cgg gag atg cag cgc gag atc ctc tcc att ttg ggc ttg
ccc cac cgc 249 Arg Glu Met Gln Arg Glu Ile Leu Ser Ile Leu Gly Leu
Pro His Arg 55 60 65 ccg cgc ccg cac ctc cag ggc aag cac aac tcg
gca ccc atg ttc atg 297 Pro Arg Pro His Leu Gln Gly Lys His Asn Ser
Ala Pro Met Phe Met 70 75 80 ctg gac ctg tac aac gcc atg gcg gtg
gag gag ggc ggc ggg ccc ggc 345 Leu Asp Leu Tyr Asn Ala Met Ala Val
Glu Glu Gly Gly Gly Pro Gly 85 90 95 ggc cag ggc ttc tcc tac ccc
tac aag gcc gtc ttc agt acc cag ggc 393 Gly Gln Gly Phe Ser Tyr Pro
Tyr Lys Ala Val Phe Ser Thr Gln Gly 100 105 110 115 ccc cct ctg gcc
agc ctg caa gat agc cat ttc ctc acc gac gcc gac 441 Pro Pro Leu Ala
Ser Leu Gln Asp Ser His Phe Leu Thr Asp Ala Asp 120 125 130 atg gtc
atg agc ttc gtc aac ctc gtg gaa cat gac aag gaa ttc ttc 489 Met Val
Met Ser Phe Val Asn Leu Val Glu His Asp Lys Glu Phe Phe 135 140 145
cac cca cgc tac cac cat cga gag ttc cgg ttt gat ctt tcc aag atc 537
His Pro Arg Tyr His His Arg Glu Phe Arg Phe Asp Leu Ser Lys Ile 150
155 160 cca gaa ggg gaa gct gtc acg gca gcc gaa ttc cgg atc tac aag
gac 585 Pro Glu Gly Glu Ala Val Thr Ala Ala Glu Phe Arg Ile Tyr Lys
Asp 165 170 175 tac atc cgg gaa cgc ttc gac aat gag acg ttc cgg atc
agc gtt tat 633 Tyr Ile Arg Glu Arg Phe Asp Asn Glu Thr Phe Arg Ile
Ser Val Tyr 180 185 190 195 cag gtg ctc cag gag cac ttg ggc agg gaa
tcg gat ctc ttc ctg ctc 681 Gln Val Leu Gln Glu His Leu Gly Arg Glu
Ser Asp Leu Phe Leu Leu 200 205 210 gac agc cgt acc ctc tgg gcc tcg
gag gag ggc tgg ctg gtg ttt gac 729 Asp Ser Arg Thr Leu Trp Ala Ser
Glu Glu Gly Trp Leu Val Phe Asp 215 220 225 atc aca gcc acc agc aac
cac tgg gtg gtc aat ccg cgg cac aac ctg 777 Ile Thr Ala Thr Ser Asn
His Trp Val Val Asn Pro Arg His Asn Leu 230 235 240 ggc ctg cag ctc
tcg gtg gag acg ctg gat ggg cag agc atc aac ccc 825 Gly Leu Gln Leu
Ser Val Glu Thr Leu Asp Gly Gln Ser Ile Asn Pro 245 250 255 aag ttg
gcg ggc ctg att ggg cgg cac ggg ccc cag aac aag cag ccc 873 Lys Leu
Ala Gly Leu Ile Gly Arg His Gly Pro Gln Asn Lys Gln Pro 260 265 270
275 ttc atg gtg gct ttc ttc aag gcc acg gag gtc cac ttc cgc agc atc
921 Phe Met Val Ala Phe Phe Lys Ala Thr Glu Val His Phe Arg Ser Ile
280 285 290 cgg tcc acg ggg agc aaa cag cgc agc cag aac cgc tcc aag
acg ccc 969 Arg Ser Thr Gly Ser Lys Gln Arg Ser Gln Asn Arg Ser Lys
Thr Pro 295 300 305 aag aac cag gaa gcc ctg cgg atg gcc aac gtg gca
gag aac agc agc 1017 Lys Asn Gln Glu Ala Leu Arg Met Ala Asn Val
Ala Glu Asn Ser Ser 310 315 320 agc gac cag agg cag gcc tgt aag aag
cac gag ctg tat gtc agc ttc 1065 Ser Asp Gln Arg Gln Ala Cys Lys
Lys His Glu Leu Tyr Val Ser Phe 325 330 335 cga gac ctg ggc tgg cag
gac tgg atc atc gcg cct gaa ggc tac gcc 1113 Arg Asp Leu Gly Trp
Gln Asp Trp Ile Ile Ala Pro Glu Gly Tyr Ala 340 345 350 355 gcc tac
tac tgt gag ggg gag tgt gcc ttc cct ctg aac tcc tac atg 1161 Ala
Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn Ser Tyr Met 360 365
370 aac gcc acc aac cac gcc atc gtg cag acg ctg gtc cac ttc atc aac
1209 Asn Ala Thr Asn His Ala Ile Val Gln Thr Leu Val His Phe Ile
Asn 375 380 385 ccg gaa acg gtg ccc aag ccc tgc tgt gcg ccc acg cag
ctc aat gcc 1257 Pro Glu Thr Val Pro Lys Pro Cys Cys Ala Pro Thr
Gln Leu Asn Ala 390 395 400 atc tcc gtc ctc tac ttc gat gac agc tcc
aac gtc atc ctg aag aaa 1305 Ile Ser Val Leu Tyr Phe Asp Asp Ser
Ser Asn Val Ile Leu Lys Lys 405 410 415 tac aga aac atg gtg gtc cgg
gcc tgt ggc tgc cac tagctcctcc 1351 Tyr Arg Asn Met Val Val Arg Ala
Cys Gly Cys His 420 425 430 gagaattcag accctttggg gccaagtttt
tctggatcct ccattgctcg ccttggccag 1411 gaaccagcag accaactgcc
ttttgtgaga ccttcccctc cctatcccca actttaaagg 1471 tgtgagagta
ttaggaaaca tgagcagcat atggcttttg atcagttttt cagtggcagc 1531
atccaatgaa caagatccta caagctgtgc aggcaaaacc tagcaggaaa aaaaaacaac
1591 gcataaagaa aaatggccgg gccaggtcat tggctgggaa gtctcagcca
tgcacggact 1651 cgtttccaga ggtaattatg agcgcctacc agccaggcca
cccagccgtg ggaggaaggg 1711 ggcgtggcaa ggggtgggca cattggtgtc
tgtgcgaaag gaaaattgac ccggaagttc 1771 ctgtaataaa tgtcacaata
aaacgaatga atgaaaaaaa aaaaaaaaaa a 1822 39 431 PRT Homo sapiens
Morphogenic protein OP1 39 Met His Val Arg Ser Leu Arg Ala Ala Ala
Pro His Ser Phe Val Ala 1 5 10 15 Leu Trp Ala Pro Leu Phe Leu Leu
Arg Ser Ala Leu Ala Asp Phe Ser 20 25 30 Leu Asp Asn Glu Val His
Ser Ser Phe Ile His Arg Arg Leu Arg Ser 35 40 45 Gln Glu Arg Arg
Glu Met Gln Arg Glu Ile Leu Ser Ile Leu Gly Leu 50 55 60 Pro His
Arg Pro Arg Pro His Leu Gln Gly Lys His Asn Ser Ala Pro 65 70 75 80
Met Phe Met Leu Asp Leu Tyr Asn Ala Met Ala Val Glu Glu Gly Gly 85
90 95 Gly Pro Gly Gly Gln Gly Phe Ser Tyr Pro Tyr Lys Ala Val Phe
Ser 100 105 110 Thr Gln Gly Pro Pro Leu Ala Ser Leu Gln Asp Ser His
Phe Leu Thr 115 120 125 Asp Ala Asp Met Val Met Ser Phe Val Asn Leu
Val Glu His Asp Lys 130 135 140 Glu Phe Phe His Pro Arg Tyr His His
Arg Glu Phe Arg Phe Asp Leu 145 150 155 160 Ser Lys Ile Pro Glu Gly
Glu Ala Val Thr Ala Ala Glu Phe Arg Ile 165 170 175 Tyr Lys Asp Tyr
Ile Arg Glu Arg Phe Asp Asn Glu Thr Phe Arg Ile 180 185 190 Ser Val
Tyr Gln
Val Leu Gln Glu His Leu Gly Arg Glu Ser Asp Leu 195 200 205 Phe Leu
Leu Asp Ser Arg Thr Leu Trp Ala Ser Glu Glu Gly Trp Leu 210 215 220
Val Phe Asp Ile Thr Ala Thr Ser Asn His Trp Val Val Asn Pro Arg 225
230 235 240 His Asn Leu Gly Leu Gln Leu Ser Val Glu Thr Leu Asp Gly
Gln Ser 245 250 255 Ile Asn Pro Lys Leu Ala Gly Leu Ile Gly Arg His
Gly Pro Gln Asn 260 265 270 Lys Gln Pro Phe Met Val Ala Phe Phe Lys
Ala Thr Glu Val His Phe 275 280 285 Arg Ser Ile Arg Ser Thr Gly Ser
Lys Gln Arg Ser Gln Asn Arg Ser 290 295 300 Lys Thr Pro Lys Asn Gln
Glu Ala Leu Arg Met Ala Asn Val Ala Glu 305 310 315 320 Asn Ser Ser
Ser Asp Gln Arg Gln Ala Cys Lys Lys His Glu Leu Tyr 325 330 335 Val
Ser Phe Arg Asp Leu Gly Trp Gln Asp Trp Ile Ile Ala Pro Glu 340 345
350 Gly Tyr Ala Ala Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu Asn
355 360 365 Ser Tyr Met Asn Ala Thr Asn His Ala Ile Val Gln Thr Leu
Val His 370 375 380 Phe Ile Asn Pro Glu Thr Val Pro Lys Pro Cys Cys
Ala Pro Thr Gln 385 390 395 400 Leu Asn Ala Ile Ser Val Leu Tyr Phe
Asp Asp Ser Ser Asn Val Ile 405 410 415 Leu Lys Lys Tyr Arg Asn Met
Val Val Arg Ala Cys Gly Cys His 420 425 430 40 98 PRT Homo sapiens
TGF-Beta1 40 Cys Cys Val Arg Gln Leu Tyr Ile Asp Phe Arg Lys Asp
Leu Gly Trp 1 5 10 15 Lys Trp Ile His Glu Pro Lys Gly Tyr His Ala
Asn Phe Cys Leu Gly 20 25 30 Pro Cys Pro Tyr Ile Trp Ser Leu Asp
Thr Gln Tyr Ser Lys Val Leu 35 40 45 Ala Leu Tyr Asn Gln His Asn
Pro Gly Ala Ser Ala Ala Pro Cys Cys 50 55 60 Val Pro Gln Ala Leu
Glu Pro Leu Pro Ile Val Tyr Tyr Val Gly Arg 65 70 75 80 Lys Pro Lys
Val Glu Gln Leu Ser Asn Met Ile Val Arg Ser Cys Lys 85 90 95 Cys
Ser 41 98 PRT Homo sapiens TGF-Beta2 41 Cys Cys Leu Arg Pro Leu Tyr
Ile Asp Phe Lys Arg Asp Leu Gly Trp 1 5 10 15 Lys Trp Ile His Glu
Pro Lys Gly Tyr Asn Ala Asn Phe Cys Ala Gly 20 25 30 Ala Cys Pro
Tyr Leu Trp Ser Ser Asp Thr Gln His Ser Arg Val Leu 35 40 45 Ser
Leu Tyr Asn Thr Ile Asn Pro Glu Ala Ser Ala Ser Pro Cys Cys 50 55
60 Val Ser Gln Asp Leu Glu Pro Leu Thr Ile Leu Tyr Tyr Ile Gly Lys
65 70 75 80 Thr Pro Lys Ile Glu Gln Leu Ser Asn Met Ile Val Lys Ser
Cys Lys 85 90 95 Cys Ser 42 98 PRT Homo sapiens TGF-Beta3 42 Cys
Cys Val Arg Pro Leu Tyr Ile Asp Phe Arg Gln Asp Leu Gly Trp 1 5 10
15 Lys Trp Val His Glu Pro Lys Gly Tyr Tyr Ala Asn Phe Cys Ser Gly
20 25 30 Pro Cys Pro Tyr Leu Arg Ser Ala Asp Thr Thr His Ser Thr
Val Leu 35 40 45 Gly Leu Tyr Asn Thr Leu Asn Pro Glu Ala Ser Ala
Ser Pro Cys Cys 50 55 60 Val Pro Gln Asp Leu Glu Pro Leu Thr Ile
Leu Tyr Tyr Val Gly Arg 65 70 75 80 Thr Pro Lys Val Glu Gln Leu Ser
Asn Met Val Val Lys Ser Cys Lys 85 90 95 Cys Ser 43 98 PRT Gallus
gallus TGF-Beta4 43 Cys Cys Val Arg Pro Leu Tyr Ile Asp Phe Arg Lys
Asp Leu Gln Trp 1 5 10 15 Lys Trp Ile His Glu Pro Lys Gly Tyr Met
Ala Asn Phe Cys Met Gly 20 25 30 Pro Cys Pro Tyr Ile Trp Ser Ala
Asp Thr Gln Tyr Thr Lys Val Leu 35 40 45 Ala Leu Tyr Asn Gln His
Asn Pro Gly Ala Ser Ala Ala Pro Cys Cys 50 55 60 Val Pro Gln Thr
Leu Asp Pro Leu Pro Ile Ile Tyr Tyr Val Gly Arg 65 70 75 80 Asn Val
Arg Val Glu Gln Leu Ser Asn Met Val Val Arg Ala Cys Lys 85 90 95
Cys Ser 44 98 PRT Xenopus laevis TGF-Beta5 44 Cys Cys Val Lys Pro
Leu Tyr Ile Asn Phe Arg Lys Asp Leu Gly Trp 1 5 10 15 Lys Trp Ile
His Glu Pro Lys Gly Tyr Glu Ala Asn Tyr Cys Leu Gly 20 25 30 Asn
Cys Pro Tyr Ile Trp Ser Met Asp Thr Gln Tyr Ser Lys Val Leu 35 40
45 Ser Leu Tyr Asn Gln Asn Asn Pro Gly Ala Ser Ile Ser Pro Cys Cys
50 55 60 Val Pro Asp Val Leu Glu Pro Leu Pro Ile Ile Tyr Tyr Val
Gly Arg 65 70 75 80 Thr Ala Lys Val Glu Gln Leu Ser Asn Met Val Val
Arg Ser Cys Asn 85 90 95 Cys Ser 45 102 PRT Drosophila melanogaster
DPP 45 Cys Arg Arg His Ser Leu Tyr Val Asp Phe Ser Asp Val Gly Trp
Asp 1 5 10 15 Asp Trp Ile Val Ala Pro Leu Gly Tyr Asp Ala Tyr Tyr
Cys His Gly 20 25 30 Lys Cys Pro Phe Pro Leu Ala Asp His Phe Asn
Ser Thr Asn His Ala 35 40 45 Val Val Gln Thr Leu Val Asn Asn Met
Asn Pro Gly Lys Val Pro Lys 50 55 60 Ala Cys Cys Val Pro Thr Gln
Leu Asp Ser Val Ala Met Leu Tyr Leu 65 70 75 80 Asn Asp Gln Ser Thr
Val Val Leu Lys Asn Tyr Gln Glu Met Thr Val 85 90 95 Val Gly Cys
Gly Cys Arg 100 46 102 PRT Xenopus laevis VG1 46 Cys Lys Lys Arg
His Leu Tyr Val Glu Phe Lys Asp Val Gly Trp Gln 1 5 10 15 Asn Trp
Val Ile Ala Pro Gln Gly Tyr Met Ala Asn Tyr Cys Tyr Gly 20 25 30
Glu Cys Pro Tyr Pro Leu Thr Glu Ile Leu Asn Gly Ser Asn His Ala 35
40 45 Ile Leu Gln Thr Leu Val His Ser Ile Glu Pro Glu Asp Ile Pro
Leu 50 55 60 Pro Cys Cys Val Pro Thr Lys Met Ser Pro Ile Ser Met
Leu Phe Tyr 65 70 75 80 Asp Asn Asn Asp Asn Val Val Leu Arg His Tyr
Glu Asn Met Ala Val 85 90 95 Asp Glu Cys Gly Cys Arg 100 47 102 PRT
Mus musculus VGR1 47 Cys Lys Lys His Glu Leu Tyr Val Ser Phe Gln
Asp Leu Gly Trp Gln 1 5 10 15 Asp Trp Ile Ile Ala Pro Lys Gly Tyr
Ala Ala Asn Tyr Cys Asp Gly 20 25 30 Glu Cys Ser Phe Pro Leu Asn
Ala His Met Asn Ala Thr Asn His Ala 35 40 45 Ile Val Gln Thr Leu
Val His Leu Met Asn Pro Glu Tyr Val Pro Lys 50 55 60 Pro Cys Cys
Ala Pro Thr Lys Leu Asn Ala Ile Ser Val Leu Tyr Phe 65 70 75 80 Asp
Asp Asn Ser Asn Val Ile Leu Lys Lys Tyr Arg Asn Met Val Val 85 90
95 Arg Ala Cys Gly Cys His 100 48 118 PRT Drosophila melanogaster
60A 48 Cys Gln Met Gln Thr Leu Tyr Ile Asp Phe Lys Asp Leu Gly Trp
His 1 5 10 15 Asp Trp Ile Ile Ala Pro Glu Gly Tyr Gly Ala Phe Tyr
Cys Ser Gly 20 25 30 Glu Cys Asn Phe Pro Leu Asn Ala His Met Asn
Ala Thr Asn His Ala 35 40 45 Ile Val Gln Thr Leu Val His Leu Leu
Glu Pro Lys Lys Val Pro Lys 50 55 60 Pro Cys Cys Ala Pro Thr Arg
Leu Gly Ala Leu Pro Val Leu Tyr His 65 70 75 80 Pro Cys Cys Ala Pro
Thr Arg Leu Gly Ala Leu Pro Val Leu Tyr His 85 90 95 Leu Asn Asp
Glu Asn Val Asn Leu Lys Lys Tyr Arg Asn Met Ile Val 100 105 110 Lys
Ser Cys Gly Cys His 115 49 101 PRT Homo sapiens BMP-2A 49 Cys Lys
Arg His Pro Leu Tyr Val Asp Phe Ser Asp Val Gly Trp Asn 1 5 10 15
Asp Trp Ile Val Ala Pro Pro Gly Tyr His Ala Phe Tyr Cys His Gly 20
25 30 Glu Cys Pro Phe Pro Leu Ala Asp His Leu Asn Ser Thr Asn His
Ala 35 40 45 Ile Val Gln Thr Leu Val Asn Ser Val Asn Ser Lys Ile
Pro Lys Ala 50 55 60 Cys Cys Val Pro Thr Glu Leu Ser Ala Ile Ser
Met Leu Tyr Leu Asp 65 70 75 80 Glu Asn Glu Lys Val Val Leu Lys Asn
Tyr Gln Asp Met Val Val Glu 85 90 95 Gly Cys Gly Cys Arg 100 50 103
PRT Homo sapiens BMP3 50 Cys Ala Arg Arg Tyr Leu Lys Val Asp Phe
Ala Asp Ile Gly Trp Ser 1 5 10 15 Glu Trp Ile Ile Ser Pro Lys Ser
Phe Asp Ala Tyr Tyr Cys Ser Gly 20 25 30 Ala Cys Gln Phe Pro Met
Pro Lys Ser Leu Lys Pro Ser Asn His Ala 35 40 45 Thr Ile Gln Ser
Ile Val Arg Ala Val Gly Val Val Pro Gly Ile Pro 50 55 60 Glu Pro
Cys Cys Val Pro Glu Lys Met Ser Ser Leu Ser Ile Leu Phe 65 70 75 80
Phe Asp Glu Asn Lys Asn Val Val Leu Lys Val Tyr Pro Asn Met Thr 85
90 95 Val Glu Ser Cys Ala Cys Arg 100 51 101 PRT Homo sapiens BMP-4
51 Cys Arg Arg His Ser Leu Tyr Val Asp Phe Ser Asp Val Gly Trp Asn
1 5 10 15 Asp Trp Ile Val Ala Pro Pro Gly Tyr Gln Ala Phe Tyr Cys
His Gly 20 25 30 Asp Cys Pro Phe Pro Leu Ala Asp His Leu Asn Ser
Thr Asn His Ala 35 40 45 Ile Val Gln Thr Leu Val Asn Ser Val Asn
Ser Ser Ile Pro Lys Ala 50 55 60 Cys Cys Val Pro Thr Glu Leu Ser
Ala Ile Ser Met Leu Tyr Leu Asp 65 70 75 80 Glu Tyr Asp Lys Val Val
Leu Lys Asn Tyr Gln Glu Met Val Val Glu 85 90 95 Gly Cys Gly Cys
Arg 100 52 102 PRT Homo sapiens BMP-5 52 Cys Lys Lys His Glu Leu
Tyr Val Ser Phe Arg Asp Leu Gly Trp Gln 1 5 10 15 Asp Trp Ile Ile
Ala Pro Glu Gly Tyr Ala Ala Phe Tyr Cys Asp Gly 20 25 30 Glu Cys
Ser Phe Pro Leu Asn Ala His Met Asn Ala Thr Asn His Ala 35 40 45
Ile Val Gln Thr Leu Val His Leu Met Phe Pro Asp His Val Pro Lys 50
55 60 Pro Cys Cys Ala Pro Thr Lys Leu Asn Ala Ile Ser Val Leu Tyr
Phe 65 70 75 80 Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Arg Asn
Met Val Val 85 90 95 Arg Ser Cys Gly Cys His 100 53 102 PRT Homo
sapiens BMP-6 53 Cys Arg Lys His Glu Leu Tyr Val Ser Phe Gln Asp
Leu Gly Trp Gln 1 5 10 15 Asp Trp Ile Ile Ala Pro Lys Gly Tyr Ala
Ala Asn Tyr Cys Asp Gly 20 25 30 Glu Cys Ser Phe Pro Leu Asn Ala
His Met Asn Ala Thr Asn His Ala 35 40 45 Ile Val Gln Thr Leu Val
His Leu Met Asn Pro Glu Tyr Val Pro Lys 50 55 60 Pro Cys Cys Ala
Pro Thr Lys Leu Asn Ala Ile Ser Val Leu Tyr Phe 65 70 75 80 Asp Asp
Asn Ser Asn Val Glu Leu Lys Lys Tyr Arg Asn Met Val Val 85 90 95
Arg Ala Cys Gly Cys His 100 54 103 PRT Gallus gallus DORSALIN 54
Cys Arg Arg Thr Ser Leu His Val Asn Phe Lys Glu Ile Gly Trp Asp 1 5
10 15 Ser Trp Ile Ile Ala Pro Lys Asp Tyr Glu Ala Phe Glu Cys Lys
Gly 20 25 30 Gly Cys Phe Phe Pro Leu Thr Asp Asn Val Thr Pro Thr
Lys His Ala 35 40 45 Ile Val Gln Thr Leu Val His Leu Gln Asn Pro
Lys Lys Ala Ser Lys 50 55 60 Ala Cys Cys Val Pro Thr Lys Leu Asp
Ala Ile Ser Ile Leu Tyr Lys 65 70 75 80 Asp Asp Ala Gly Val Pro Thr
Leu Ile Tyr Asn Tyr Glu Gly Met Lys 85 90 95 Val Ala Glu Cys Gly
Cys Arg 100 55 102 PRT Homo sapiens OP-1 55 Cys Lys Lys His Glu Leu
Tyr Val Ser Phe Arg Asp Leu Gly Trp Gln 1 5 10 15 Asp Trp Ile Ile
Ala Pro Glu Gly Tyr Ala Ala Tyr Tyr Cys Glu Gly 20 25 30 Glu Cys
Ala Phe Pro Leu Asn Ser Tyr Met Asn Ala Thr Asn His Ala 35 40 45
Ile Val Gln Thr Leu Val His Phe Ile Asn Pro Glu Thr Val Pro Lys 50
55 60 Pro Cys Cys Ala Pro Thr Gln Leu Asn Ala Ile Ser Val Leu Tyr
Phe 65 70 75 80 Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Arg Asn
Met Val Val 85 90 95 Arg Ala Cys Gly Cys His 100 56 102 PRT Homo
sapiens OP-2 56 Cys Arg Arg His Glu Leu Tyr Val Ser Phe Gln Asp Leu
Gly Trp Leu 1 5 10 15 Asp Trp Val Ile Ala Pro Gln Gly Tyr Ser Ala
Tyr Tyr Cys Glu Gly 20 25 30 Glu Cys Ser Phe Pro Leu Asp Ser Cys
Met Asn Ala Thr Asn His Ala 35 40 45 Ile Leu Gln Ser Leu Val His
Leu Met Lys Pro Asn Ala Val Pro Lys 50 55 60 Ala Cys Cys Ala Pro
Thr Lys Leu Ser Ala Thr Ser Val Leu Tyr Tyr 65 70 75 80 Asp Ser Ser
Asn Asn Val Ile Leu Arg Lys His Arg Asn Met Val Val 85 90 95 Lys
Ala Cys Gly Cys His 100 57 102 PRT Mus musculus OP-3 57 Cys Arg Arg
His Glu Leu Tyr Val Ser Phe Arg Asp Leu Gly Trp Leu 1 5 10 15 Asp
Ser Val Ile Ala Pro Gln Gly Tyr Ser Ala Tyr Tyr Cys Ala Gly 20 25
30 Glu Cys Ile Tyr Pro Leu Asn Ser Cys Met Asn Ser Thr Asn His Ala
35 40 45 Thr Met Gln Ala Leu Val His Leu Met Lys Pro Asp Ile Ile
Pro Lys 50 55 60 Val Cys Cys Val Pro Thr Glu Leu Ser Ala Ile Ser
Leu Leu Tyr Tyr 65 70 75 80 Asp Arg Asn Asn Asn Val Ile Leu Arg Arg
Glu Arg Asn Met Val Val 85 90 95 Gln Ala Cys Gly Cys His 100 58 107
PRT Mus musculus GDF-1 58 Cys Arg Thr Arg Arg Leu His Val Ser Phe
Arg Glu Val Gly Trp His 1 5 10 15 Arg Trp Val Ile Ala Pro Arg Gly
Phe Leu Ala Asn Phe Cys Gln Gly 20 25 30 Thr Cys Ala Leu Pro Glu
Thr Leu Arg Gly Pro Gly Gly Pro Pro Ala 35 40 45 Leu Asn His Ala
Val Leu Arg Ala Leu Met His Ala Ala Ala Pro Thr 50 55 60 Pro Gly
Ala Gly Ser Pro Cys Cys Val Pro Glu Arg Leu Ser Pro Ile 65 70 75 80
Ser Val Leu Phe Phe Asp Asn Ser Asp Asn Val Val Leu Arg His Tyr 85
90 95 Glu Asp Met Val Val Asp Glu Cys Gly Cys Arg 100 105 59 101
PRT Mus musculus GDF-3 59 Cys His Arg His Gln Leu Phe Ile Asn Phe
Gln Asp Leu Gly Trp His 1 5 10 15 Lys Trp Val Ile Ala Pro Lys Gly
Phe Met Ala Asn Tyr Cys His Gly 20 25 30 Glu Cys Pro Phe Ser Met
Thr Thr Tyr Leu Asn Ser Ser Asn Tyr Ala 35 40 45 Phe Met Gln Ala
Leu Met His Met Ala Asp Pro Lys Val Pro Lys Ala 50 55 60 Val Cys
Val Pro Thr Lys Leu Ser Pro Ile Ser Met Leu Tyr Gln Asp 65 70 75 80
Ser Asp Lys Asn Val Ile Leu Arg His Tyr Glu Asp Met Val Val Asp 85
90 95 Glu Cys Gly Cys Gly 100 60 102 PRT Mus musculus GDF-9 60 Cys
Glu Leu His Asp Phe Arg Leu Ser Phe Ser Gln Leu Lys Trp Asp 1 5 10
15 Asn Trp Ile Val Ala Pro His Arg Tyr Asn Pro Arg Tyr Cys Lys Gly
20 25 30 Asp Cys Pro Arg Ala Val Arg His Arg Tyr Gly Ser Pro Val
His Thr 35 40 45 Met Val Gln Asn Ile Ile Tyr Glu Lys Leu Asp Pro
Ser Val Pro Arg 50 55 60 Pro Ser Cys Val Pro Gly Lys Tyr Ser Pro
Leu Ser Val Leu Thr Ile 65 70
75 80 Glu Pro Asp Gly Ser Ile Ala Tyr Lys Glu Tyr Glu Asp Met Ile
Ala 85 90 95 Thr Arg Cys Thr Cys Arg 100 61 105 PRT Homo sapiens
INHIBIN-Alpha 61 Cys His Arg Val Ala Leu Asn Ile Ser Phe Gln Glu
Leu Gly Trp Glu 1 5 10 15 Arg Trp Ile Val Tyr Pro Pro Ser Phe Ile
Phe His Tyr Cys His Gly 20 25 30 Gly Cys Gly Leu His Ile Pro Pro
Asn Leu Ser Leu Pro Val Pro Gly 35 40 45 Ala Pro Pro Thr Pro Ala
Gln Pro Tyr Ser Leu Leu Pro Gly Ala Gln 50 55 60 Pro Cys Cys Ala
Ala Leu Pro Gly Thr Met Arg Pro Leu His Val Arg 65 70 75 80 Thr Thr
Ser Asp Gly Gly Tyr Ser Phe Lys Tyr Glu Thr Val Pro Asn 85 90 95
Leu Leu Thr Gln His Cys Ala Cys Ile 100 105 62 106 PRT Bos taurus
INHIBIN-BetaA 62 Cys Cys Lys Lys Gln Phe Phe Val Ser Phe Lys Asp
Ile Gly Trp Asn 1 5 10 15 Asp Trp Ile Ile Ala Pro Ser Gly Tyr His
Ala Asn Tyr Cys Glu Gly 20 25 30 Glu Cys Pro Ser His Ile Ala Gly
Thr Ser Gly Ser Ser Leu Ser Phe 35 40 45 His Ser Thr Val Ile Asn
His Tyr Arg Met Arg Gly His Ser Pro Phe 50 55 60 Ala Asn Leu Lys
Ser Cys Cys Val Pro Thr Lys Leu Arg Pro Met Ser 65 70 75 80 Met Leu
Tyr Tyr Asp Asp Gly Gln Asn Ile Ile Lys Lys Asp Ile Gln 85 90 95
Asn Met Ile Val Glu Glu Cys Gly Cys Ser 100 105 63 106 PRT Homo
sapiens INHIBIN-Betab 63 Cys Cys Lys Lys Gln Phe Phe Val Ser Phe
Lys Asp Ile Gly Trp Asn 1 5 10 15 Asp Trp Ile Ile Ala Pro Ser Gly
Tyr His Ala Asn Tyr Cys Glu Gly 20 25 30 Glu Cys Pro Ser His Ile
Ala Gly Thr Ser Gly Ser Ser Leu Ser Phe 35 40 45 His Ser Thr Val
Ile Asn His Tyr Arg Met Arg Gly His Ser Pro Phe 50 55 60 Ala Asn
Leu Lys Ser Cys Cys Val Pro Thr Lys Leu Arg Pro Met Ser 65 70 75 80
Met Leu Tyr Tyr Asp Asp Gly Gln Asn Ile Ile Lys Lys Asp Ile Gln 85
90 95 Asn Met Ile Val Glu Glu Cys Gly Cys Ser 100 105 64 98 PRT
Artificial Sequence Description of Artificial Sequence TGF-B
SUBGROUP SEQUENCE PATTERN 64 Cys Cys Val Arg Pro Leu Tyr Ile Asp
Phe Arg Xaa Asp Leu Gly Trp 1 5 10 15 Lys Trp Ile His Glu Pro Lys
Gly Tyr Xaa Ala Asn Phe Cys Xaa Gly 20 25 30 Xaa Cys Pro Tyr Xaa
Trp Ser Xaa Asp Thr Gln Xaa Ser Xaa Val Leu 35 40 45 Xaa Leu Tyr
Asn Xaa Xaa Asn Pro Xaa Ala Ser Ala Xaa Pro Cys Cys 50 55 60 Val
Pro Gln Xaa Leu Glu Pro Leu Xaa Ile Xaa Tyr Tyr Val Gly Arg 65 70
75 80 Xaa Xaa Lys Val Glu Gln Leu Ser Asn Met Xaa Val Xaa Ser Cys
Lys 85 90 95 Cys Ser 65 104 PRT Artificial Sequence Description of
Artificial Sequence VG/DPP SUBGROUP SEQUENCE PATTERN 65 Cys Xaa Xaa
Xaa Xaa Leu Tyr Val Xaa Phe Xaa Asp Xaa Gly Trp Xaa 1 5 10 15 Asp
Trp Ile Ile Ala Pro Xaa Gly Tyr Xaa Ala Xaa Tyr Cys Xaa Gly 20 25
30 Xaa Cys Xaa Phe Pro Leu Xaa Xaa Xaa Xaa Asn Xaa Thr Asn His Ala
35 40 45 Ile Xaa Gln Thr Leu Val Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa
Xaa Pro 50 55 60 Lys Xaa Cys Cys Xaa Pro Thr Xaa Leu Xaa Ala Xaa
Ser Xaa Leu Tyr 65 70 75 80 Xaa Asp Xaa Xaa Xaa Xaa Xaa Val Xaa Leu
Xaa Xaa Tyr Xaa Xaa Met 85 90 95 Xaa Val Xaa Xaa Cys Gly Cys Xaa
100 66 107 PRT Artificial Sequence Description of Artificial
Sequence GDF SUBGROUP PATTERN 66 Cys Xaa Xaa Xaa Xaa Xaa Xaa Xaa
Xaa Phe Xaa Xaa Xaa Xaa Trp Xaa 1 5 10 15 Xaa Trp Xaa Xaa Ala Pro
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Cys Xaa Gly 20 25 30 Xaa Cys Xaa Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 55 60
Pro Xaa Xaa Xaa Xaa Xaa Xaa Cys Val Pro Xaa Xaa Xaa Ser Pro Xaa 65
70 75 80 Ser Xaa Leu Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa
Xaa Tyr 85 90 95 Glu Asp Met Xaa Xaa Xaa Xaa Cys Xaa Cys Xaa 100
105 67 109 PRT Artificial Sequence Description of Artificial
Sequence INHIBIN SUBGROUP PATTERN 67 Cys Xaa Xaa Xaa Xaa Xaa Xaa
Xaa Xaa Phe Xaa Xaa Xaa Gly Trp Xaa 1 5 10 15 Xaa Trp Ile Xaa Xaa
Pro Xaa Xaa Xaa Xaa Xaa Xaa Tyr Cys Xaa Gly 20 25 30 Xaa Cys Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 35 40 45 Xaa
Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa 50 55
60 Xaa Xaa Xaa Xaa Xaa Cys Cys Xaa Xaa Xaa Pro Xaa Xaa Xaa Xaa Xaa
65 70 75 80 Xaa Xaa Xaa Xaa Xaa Xaa Xaa Asp Xaa Xaa Xaa Xaa Xaa Xaa
Xaa Xaa 85 90 95 Xaa Xaa Xaa Asn Xaa Xaa Xaa Xaa Xaa Cys Xaa Cys
Xaa 100 105 68 139 PRT Homo sapiens Mature H2223 mutant 68 Ser Thr
Gly Ser Lys Gln Arg Ser Gln Asn Arg Ser Lys Thr Pro Lys 1 5 10 15
Asn Gln Glu Ala Leu Arg Met Ala Asn Val Ala Glu Asn Ser Ser Ser 20
25 30 Asp Gln Arg Gln Ala Cys Lys Lys His Glu Leu Tyr Val Ser Phe
Arg 35 40 45 Asp Leu Gly Trp Gln Asp Trp Ile Ile Ala Pro Glu Gly
Tyr Ala Ala 50 55 60 Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro Leu
Asn Ser Tyr Met Asn 65 70 75 80 Ala Thr Asn His Ala Ile Val Gln Thr
Leu Val His Phe Ile Asn Pro 85 90 95 Glu Thr Val Pro Lys Pro Cys
Cys Ala Pro Thr Gln Leu Asn Ala Ile 100 105 110 Ser Val Leu Tyr Phe
Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr 115 120 125 Glu Asp Met
Val Val Glu Ala Cys Gly Cys Arg 130 135 69 117 PRT Homo sapiens
Trypsin truncated H2223 mutant 69 Met Ala Asn Val Ala Glu Asn Ser
Ser Ser Asp Gln Arg Gln Ala Cys 1 5 10 15 Lys Lys His Glu Leu Tyr
Val Ser Phe Arg Asp Leu Gly Trp Gln Asp 20 25 30 Trp Ile Ile Ala
Pro Glu Gly Tyr Ala Ala Tyr Tyr Cys Glu Gly Glu 35 40 45 Cys Ala
Phe Pro Leu Asn Ser Tyr Met Asn Ala Thr Asn His Ala Ile 50 55 60
Val Gln Thr Leu Val His Phe Ile Asn Pro Glu Thr Val Pro Lys Pro 65
70 75 80 Cys Cys Ala Pro Thr Gln Leu Asn Ala Ile Ser Val Leu Tyr
Phe Asp 85 90 95 Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Glu Asp
Met Val Val Glu 100 105 110 Ala Cys Gly Cys Arg 115 70 33 DNA
Artificial Sequence Description of Artificial Sequence Primer #1 70
gcg ccc acg cag ctc agc gct atc tcc gtc ctc 33 Ala Pro Thr Gln Leu
Ser Ala Ile Ser Val Leu 1 5 10 71 11 PRT Artificial Sequence Amino
acid sequence encoded by Primer #1 71 Ala Pro Thr Gln Leu Ser Ala
Ile Ser Val Leu 1 5 10 72 43 DNA Artificial Sequence Description of
Artificial Sequence Primer #2 72 ctatctgcag ccacaagctt cgaccaccat
gtcttcgtat ttc 43 73 43 DNA Artificial Sequence Description of
Artificial Sequence Complement of Primer #2 73 g aaa tac gaa gac
atg gtg gtc gaa gct tgt ggc tgc aga tag 43 Lys Tyr Glu Asp Met Val
Val Glu Ala Cys Gly Cys Arg 1 5 10 74 13 PRT Artificial Sequence
Amino acid sequence encoded by complement of Primer #2 74 Lys Tyr
Glu Asp Met Val Val Glu Ala Cys Gly Cys Arg 1 5 10 75 44 DNA
Artificial Sequence Description of Artificial Sequence the sequence
between the T7 promoter, at the XbaI site, and the ATG codon 75
tctagaataa ttttgtttaa cctttaagaa ggagatatac gatg 44 76 19 DNA
Artificial Sequence Description of Artificial Sequence Primer #3 76
taatacgact cactatagg 19 77 18 DNA Artificial Sequence Description
of Artificial Sequence Primer #4 77 gctgagctgc gtgggcgc 18 78 18
DNA Artificial Sequence Description of Artificial Sequence
complement of Primer #4x 78 gcg ccc acg cag ctc agc 18 Ala Pro Thr
Gln Leu Ser 1 5 79 6 PRT Artificial Sequence Amino acid sequence
encoded by complement of Primer #4 79 Ala Pro Thr Gln Leu Ser 1 5
80 23 DNA Artificial Sequence Description of Artificial Sequence
Primer #5 80 ggatcctatc tgcagccaca agc 23 81 23 DNA Artificial
Sequence Description of Artificial Sequence complement of Primer #5
81 gct tgt ggc tgc aga tag gatcc 23 Ala Cys Gly Cys Arg 1 5 82 5
PRT Artificial Sequence Amino acid sequence encoded by complement
of Primer #5 82 Ala Cys Gly Cys Arg 1 5 83 102 PRT Homo sapiens
CDMP-1/GDF-5 83 Cys Ser Arg Lys Ala Leu His Val Asn Phe Lys Asp Met
Gly Trp Asp 1 5 10 15 Asp Trp Ile Ile Ala Pro Leu Glu Tyr Glu Ala
Phe His Cys Glu Gly 20 25 30 Leu Cys Glu Phe Pro Leu Arg Ser His
Leu Glu Pro Thr Asn His Ala 35 40 45 Val Ile Gln Thr Leu Met Asn
Ser Met Asp Pro Glu Ser Thr Pro Pro 50 55 60 Thr Cys Cys Val Pro
Thr Arg Leu Ser Pro Ile Ser Ile Leu Phe Ile 65 70 75 80 Asp Ser Ala
Asn Asn Val Val Tyr Lys Gln Tyr Glu Asp Met Val Val 85 90 95 Glu
Ser Cys Gly Cys Arg 100 84 102 PRT Homo sapiens CDMP-2/GDF-6 84 Cys
Ser Lys Lys Pro Leu His Val Asn Phe Lys Glu Leu Gly Trp Asp 1 5 10
15 Asp Trp Ile Ile Ala Pro Leu Glu Tyr Glu Ala Tyr His Cys Glu Gly
20 25 30 Val Cys Asp Phe Pro Leu Arg Ser His Leu Glu Pro Thr Asn
His Ala 35 40 45 Ile Ile Gln Thr Leu Met Asn Ser Met Asp Pro Gly
Ser Thr Pro Pro 50 55 60 Ser Cys Cys Val Pro Thr Lys Leu Thr Pro
Ile Ser Ile Leu Tyr Ile 65 70 75 80 Asp Ala Gly Asn Asn Val Val Tyr
Lys Gln Tyr Glu Asp Met Val Val 85 90 95 Glu Ser Cys Gly Cys Arg
100 85 102 PRT Mus musculus GDF-6 85 Cys Ser Arg Lys Pro Leu His
Val Asn Phe Lys Glu Leu Gly Trp Asp 1 5 10 15 Asp Trp Ile Ile Ala
Pro Leu Glu Tyr Glu Ala Tyr His Cys Glu Gly 20 25 30 Val Cys Asp
Phe Pro Leu Arg Ser His Leu Glu Pro Thr Asn His Ala 35 40 45 Ile
Ile Gln Thr Leu Met Asn Ser Met Asp Pro Gly Ser Thr Pro Pro 50 55
60 Ser Cys Cys Val Pro Thr Lys Leu Thr Pro Ile Ser Ile Leu Tyr Ile
65 70 75 80 Asp Ala Gly Asn Asn Val Val Tyr Lys Gln Tyr Glu Asp Met
Val Val 85 90 95 Glu Ser Cys Gly Cys Arg 100 86 102 PRT Bos taurus
CDMP-2 86 Cys Ser Lys Lys Pro Leu His Val Asn Phe Lys Glu Leu Gly
Trp Asp 1 5 10 15 Asp Trp Ile Ile Ala Pro Leu Glu Tyr Glu Ala Tyr
His Cys Glu Gly 20 25 30 Val Cys Asp Phe Pro Leu Arg Ser His Leu
Glu Pro Thr Asn His Ala 35 40 45 Ile Ile Gln Thr Leu Met Asn Ser
Met Asp Pro Gly Ser Thr Pro Pro 50 55 60 Ser Cys Cys Val Pro Thr
Lys Leu Thr Pro Ile Ser Ile Leu Tyr Ile 65 70 75 80 Asp Ala Gly Asn
Asn Val Val Tyr Asn Glu Tyr Glu Glu Met Val Val 85 90 95 Glu Ser
Cys Gly Cys Arg 100 87 102 PRT Mus musculus GDF-7 87 Cys Ser Arg
Lys Ser Leu His Val Asp Phe Lys Glu Leu Gly Trp Asp 1 5 10 15 Asp
Trp Ile Ile Ala Pro Leu Asp Tyr Glu Ala Tyr His Cys Glu Gly 20 25
30 Val Cys Asp Phe Pro Leu Arg Ser His Leu Glu Pro Thr Asn His Ala
35 40 45 Ile Ile Gln Thr Leu Leu Asn Ser Met Ala Pro Asp Ala Ala
Pro Ala 50 55 60 Ser Cys Cys Val Pro Ala Arg Leu Ser Pro Ile Ser
Ile Leu Tyr Ile 65 70 75 80 Asp Ala Ala Asn Asn Val Val Tyr Lys Gln
Tyr Glu Asp Met Val Val 85 90 95 Glu Ala Cys Gly Cys Arg 100 88 102
PRT Homo sapiens CDMP-3 construct 88 Cys Ser Arg Lys Pro Leu His
Val Asp Phe Lys Glu Leu Gly Trp Asp 1 5 10 15 Asp Trp Ile Ile Ala
Pro Leu Asp Tyr Glu Ala Tyr His Cys Glu Gly 20 25 30 Leu Cys Asp
Phe Pro Leu Arg Ser His Leu Glu Pro Thr Asn His Ala 35 40 45 Ile
Ile Gln Thr Leu Leu Asn Ser Met Ala Pro Asp Ala Ala Pro Ala 50 55
60 Ser Cys Cys Val Pro Ala Arg Leu Ser Pro Ile Ser Ile Leu Tyr Ile
65 70 75 80 Asp Ala Ala Asn Asn Val Val Tyr Lys Gln Tyr Glu Asp Met
Val Val 85 90 95 Glu Ala Cys Gly Cys Arg 100 89 129 PRT Homo
sapiens H2487 89 Met Thr Met Ile Thr Asn Ser Leu Ala Ser Trp Arg
Glu Pro Ser Phe 1 5 10 15 Met Ala Leu Ser Ser Ser Asp Gln Arg Gln
Ala Cys Lys Lys His Glu 20 25 30 Leu Tyr Val Ser Phe Arg Asp Leu
Gly Trp Gln Asp Trp Ile Ile Ala 35 40 45 Pro Glu Gly Tyr Ala Ala
Tyr Tyr Cys Glu Gly Glu Cys Ala Phe Pro 50 55 60 Leu Asn Ser Tyr
Met Asn Ala Thr Asn His Ala Ile Val Gln Thr Leu 65 70 75 80 Val His
Phe Ile Asn Pro Glu Thr Val Pro Lys Pro Cys Cys Ala Pro 85 90 95
Thr Gln Leu Ser Ala Ile Ser Val Leu Tyr Phe Asp Asp Ser Ser Asn 100
105 110 Val Ile Leu Lys Lys Tyr Glu Asp Met Val Val Glu Ala Cys Gly
Cys 115 120 125 Arg 90 405 DNA Homo sapiens H2487 90 atgaccatga
ttacgaattc cctggccagc tggagagagc caagcttcat ggccttaagc 60
agcagcgacc agaggcaggc ctgtaagaag cacgagctgt atgtcagctt ccgagacctg
120 ggctggcagg actggatcat cgcgcctgaa ggctacgccg cctactactg
tgagggggag 180 tgtgccttcc ctctgaactc ctacatgaac gccaccaacc
acgccatcgt gcagacgctg 240 gtccacttca tcaacccgga aacggtgccc
aagccctgct gtgcgcccac gcagctcagc 300 gctatctccg tcctctactt
cgatgacagc tccaacgtca tcctgaagaa atacgaagac 360 atggtggtcg
aagcttgtgg ctgcagatag ctcctccgag aattc 405 91 46 PRT Homo sapiens
H2440 91 Met Ala Asp Asn His His His His His His Met Gly Ser Lys
Gln Arg 1 5 10 15 Ser Gln Asn Arg Ser Lys Thr Pro Lys Asn Gln Glu
Ala Leu Arg Met 20 25 30 Ala Asn Val Ala Glu Asn Ser Ser Ser Asp
Gln Arg Gln Ala 35 40 45 92 143 DNA Homo sapiens H2440 92
ccatggctga caaccatcac catcatcatc accatatggg gagcaaacag cgcagccaga
60 accgctccaa gacgcccaag aaccaggaag ccctgcggat ggccaacgtg
gcagagaaca 120 gcagcagcga ccagaggcag gcc 143 93 241 DNA Homo
sapiens H2521 93 atgatcgaat tcatggctga caacaaattc aacaaggaac
agcagaacgc gttctacgag 60 atcttgcacc tgccgaacct gaacgaagag
cagcgtaacg gcttcatcca aagcctgaaa 120 gaagagccgt ctcagtctgc
gaatctgcta gcggatgcca agaaactgaa cgatgcgcag 180 gcaccgaaat
cggccatggc caacgtggca gagaacagca gcagcgacca gaggcaggcc 240 t 241 94
80 PRT Homo sapiens H2521 94 Met Ile Glu Phe Met Ala Asp Asn Lys
Phe Asn Lys Glu Gln Gln Asn 1 5 10 15 Ala Phe Tyr Glu Ile Leu His
Leu Pro Asn Leu Asn Glu Glu Gln Arg
20 25 30 Asn Gly Phe Ile Gln Ser Leu Lys Glu Glu Pro Ser Gln Ser
Ala Asn 35 40 45 Leu Leu Ala Asp Ala Lys Lys Leu Asn Asp Ala Gln
Ala Pro Lys Ser 50 55 60 Ala Met Ala Asn Val Ala Glu Asn Ser Ser
Ser Asp Gln Arg Gln Ala 65 70 75 80 95 334 DNA Homo sapiens H2525
95 atgatcgaat tcatggctga caacaaattc aacaaggaac agcagaacgc
gttctacgag 60 atcttgcacc tgccgaacct gaacgaagag cagcgtaacg
gcttcatcca aagcctgaaa 120 gaagagccgt ctcagtctgc gaatctgcta
gcggatgcca agaaactgaa cgatgcgcag 180 gcaccgaaat cggccatggc
tgacaaccat caccatcatc accatatggg gagcaaacag 240 cgcagccaga
accgctccaa gacgcccaag aaccaggaag ccctgcggat ggccaacgtg 300
gcagagaaca gcagcagcga ccagaggcag gcct 334 96 111 PRT Homo sapiens
H2525 96 Met Ile Glu Phe Met Ala Asp Asn Lys Phe Asn Lys Glu Gln
Gln Asn 1 5 10 15 Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn
Glu Glu Gln Arg 20 25 30 Asn Gly Phe Ile Gln Ser Leu Lys Glu Glu
Pro Ser Gln Ser Ala Asn 35 40 45 Leu Leu Ala Asp Ala Lys Lys Leu
Asn Asp Ala Gln Ala Pro Lys Ser 50 55 60 Ala Met Ala Asp Asn His
His His His His His Met Gly Ser Lys Gln 65 70 75 80 Arg Ser Gln Asn
Arg Ser Lys Thr Pro Lys Asn Gln Glu Ala Leu Arg 85 90 95 Met Ala
Asn Val Ala Glu Asn Ser Ser Ser Asp Gln Arg Gln Ala 100 105 110 97
268 DNA Homo sapiens H2527 97 atgatcgaat tcatggctga caacaaattc
aacaaggaac agcagaacgc gttctacgag 60 atcttgcacc tgccgaacct
gaacgaagag cagcgtaacg gcttcatcca aagcctgaaa 120 gaagagccgt
ctcagtctgc gaatctgcta gcggatgcca agaaactgaa cgatgcgcag 180
gcaccgaaat cggatcatca tcaccatcac cactcggatc ccatggccaa cgtggcagag
240 aacagcagca gcgaccagag gcaggcct 268 98 89 PRT Homo sapiens H2527
98 Met Ile Glu Phe Met Ala Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn
1 5 10 15 Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu
Gln Arg 20 25 30 Asn Gly Phe Ile Gln Ser Leu Lys Glu Glu Pro Ser
Gln Ser Ala Asn 35 40 45 Leu Leu Ala Asp Ala Lys Lys Leu Asn Asp
Ala Gln Ala Pro Lys Ser 50 55 60 Asp His His His His His His Ser
Asp Pro Met Ala Asn Val Ala Glu 65 70 75 80 Asn Ser Ser Ser Asp Gln
Arg Gln Ala 85 99 647 DNA Homo sapiens H2528 99 ccatgatcga
attcatggct gacaacaaat tcaacaagga acagcagaac gcgttctacg 60
agatcttgca cctgccgaac ctgaacgaag agcagcgtaa cggcttcatc caaagcctga
120 aagaagagcc gtctcagtct gcgaatctgc tagcggatgc caagaaactg
aacgatgcgc 180 aggcaccgaa atcggatcat catcaccatc accactcgga
tcccatggcg ttggccggga 240 cgcgtacagc gcagggcagc ggcggaggtg
ccggcagagg tcatggtcga cgtggtagat 300 ctcgctgcag ccgcaagccg
ttgcacgtgg acttcaagga gctcggctgg gacgactgga 360 tcatcgcgcc
gctggactac gaggcgtacc actgcgaggg cctttgcgac ttccctttgc 420
gttcgcacct cgagcccacc aaccatgcca tcattcagac gctgctcaac tccatggcac
480 cagacgcggc gccggcctcc tgctgtgtgc cagcgcgcct cagccccatc
agcatcctct 540 acatcgacgc cgccaacaac gttgtctaca agcaatacga
ggacatggtg gtggaggcct 600 gcggctgtag gtaagcttgt ggctgcagat
agctcctccg agaattc 647 100 203 PRT Homo sapiens H2528 100 Met Ile
Glu Phe Met Ala Asp Asn Lys Phe Asn Lys Glu Gln Gln Asn 1 5 10 15
Ala Phe Tyr Glu Ile Leu His Leu Pro Asn Leu Asn Glu Glu Gln Arg 20
25 30 Asn Gly Phe Ile Gln Ser Leu Lys Glu Glu Pro Ser Gln Ser Ala
Asn 35 40 45 Leu Leu Ala Asp Ala Lys Lys Leu Asn Asp Ala Gln Ala
Pro Lys Ser 50 55 60 Asp His His His His His His Ser Asp Pro Met
Ala Leu Ala Gly Thr 65 70 75 80 Arg Thr Ala Gln Gly Ser Gly Gly Gly
Ala Gly Arg Gly His Gly Arg 85 90 95 Arg Gly Arg Ser Arg Cys Ser
Arg Lys Pro Leu His Val Asp Phe Lys 100 105 110 Glu Leu Gly Trp Asp
Asp Trp Ile Ile Ala Pro Leu Asp Tyr Glu Ala 115 120 125 Tyr His Cys
Glu Gly Leu Cys Asp Phe Pro Leu Arg Ser His Leu Glu 130 135 140 Pro
Thr Asn His Ala Ile Ile Gln Thr Leu Leu Asn Ser Met Ala Pro 145 150
155 160 Asp Ala Ala Pro Ala Ser Cys Cys Val Pro Ala Arg Leu Ser Pro
Ile 165 170 175 Ser Ile Leu Tyr Ile Asp Ala Ala Asn Asn Val Val Tyr
Lys Gln Tyr 180 185 190 Glu Asp Met Val Val Glu Ala Cys Gly Cys Arg
195 200 101 47 DNA Homo sapiens H2469 101 ccatggccaa cgtggcagag
aacagcagca gcgaccagag gcaggcc 47 102 15 PRT Homo sapiens H2469 102
Met Ala Asn Val Ala Glu Asn Ser Ser Ser Asp Gln Arg Gln Ala 1 5 10
15 103 129 DNA Homo sapiens H2510 103 atgtccacgg ggagcaaaca
gcgcagccag aaccgctcca agacgcccaa gaaccaggaa 60 gccctgcgga
tggccagctg gagagagcca agcttcatgg ccttaagcag cagcgaccag 120
aggcaggcc 129 104 43 PRT Homo sapiens H2510 104 Met Ser Thr Gly Ser
Lys Gln Arg Ser Gln Asn Arg Ser Lys Thr Pro 1 5 10 15 Lys Asn Gln
Glu Ala Leu Arg Met Ala Ser Trp Arg Glu Pro Ser Phe 20 25 30 Met
Ala Leu Ser Ser Ser Asp Gln Arg Gln Ala 35 40 105 168 DNA Homo
sapiens H2523 105 atgtccacgg ggagcaaaca gcgcagccag aaccgctcca
agacgcccaa gaaccaggaa 60 gccctgcgga tggccagctg gagagagcca
agcttcatgg ccttaagcag cagcgaccag 120 aggcaggcca acgtggcaga
gaacagcagc agcgaccaga ggcaggcc 168 106 56 PRT Homo sapiens H2523
106 Met Ser Thr Gly Ser Lys Gln Arg Ser Gln Asn Arg Ser Lys Thr Pro
1 5 10 15 Lys Asn Gln Glu Ala Leu Arg Met Ala Ser Trp Arg Glu Pro
Ser Phe 20 25 30 Met Ala Leu Ser Ser Ser Asp Gln Arg Gln Ala Asn
Val Ala Glu Asn 35 40 45 Ser Ser Ser Asp Gln Arg Gln Ala 50 55 107
194 DNA Homo sapiens H2524 107 ccatggctga caaccatcac catcatcacc
atatggggag caaacagcgc agccagaacc 60 gctccaagac gcccaagaac
caggaagccc tgcggatggc cagctggaga gagccaagct 120 tcatggcctt
aagcagcagc gaccagaggc aggccaacgt ggcagagaac agcagcagcg 180
accagaggca ggcc 194 108 64 PRT Homo sapiens H2524 108 Met Ala Asp
Asn His His His His His His Met Gly Ser Lys Gln Arg 1 5 10 15 Ser
Gln Asn Arg Ser Lys Thr Pro Lys Asn Gln Glu Ala Leu Arg Met 20 25
30 Ala Ser Trp Arg Glu Pro Ser Phe Met Ala Leu Ser Ser Ser Asp Gln
35 40 45 Arg Gln Ala Asn Val Ala Glu Asn Ser Ser Ser Asp Gln Arg
Gln Ala 50 55 60 109 39 PRT Homo sapiens 2421 109 Pro Thr Cys Cys
Val Pro Thr Arg Leu Ser Pro Ile Ser Ile Leu Phe 1 5 10 15 Ile Asp
Ala Ser Asn Asn Val Val Leu Lys Lys Tyr Arg Asn Met Val 20 25 30
Val Arg Ala Cys Gly Cys Arg 35 110 39 PRT Homo sapiens H2406 110
Asn Ser Cys Cys Val Pro Thr Lys Leu Thr Pro Ile Ser Ile Leu Tyr 1 5
10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Arg Asn Met
Val 20 25 30 Val Arg Ala Cys Gly Cys Arg 35 111 39 PRT Homo sapiens
2410 111 Asn Ser Cys Cys Val Pro Thr Glu Leu Ser Ala Ile Ser Met
Leu Tyr 1 5 10 15 Leu Asp Glu Asn Glu Lys Val Val Leu Lys Asn Tyr
Gln Asp Met Val 20 25 30 Val Glu Gly Cys Gly Cys Arg 35 112 39 PRT
Homo sapiens 2247 112 Lys Pro Cys Cys Ala Pro Thr Gln Leu Asn Ala
Ile Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu
Lys Lys Tyr Arg Asn Met Val 20 25 30 Val Arg Ala Cys Gly Cys Arg 35
113 39 PRT Homo sapiens 2234 113 Lys Pro Cys Cys Ala Pro Thr Gln
Leu Asn Ala Ile Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp Ser Ser Asn
Val Ile Leu Lys Lys Tyr Glu Asp Met Val 20 25 30 Val Arg Ala Cys
Gly Cys Arg 35 114 39 PRT Homo sapiens 2233 114 Lys Pro Cys Cys Ala
Pro Thr Gln Leu Asn Ala Ile Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp
Ser Ser Asn Val Ile Leu Lys Lys Tyr Glu Asp Met Val 20 25 30 Val
Glu Ala Cys Gly Cys Arg 35 115 39 PRT Homo sapiens 2418 115 Asn Ser
Cys Cys Val Pro Thr Lys Leu Thr Pro Ile Ser Val Leu Tyr 1 5 10 15
Phe Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Glu Asp Met Val 20
25 30 Val Glu Ser Cys Gly Cys Arg 35 116 39 PRT Homo sapiens 2443
116 Asn Ser Cys Cys Val Pro Thr Lys Leu Thr Pro Ile Ser Val Leu Tyr
1 5 10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Glu Asp
Met Val 20 25 30 Val Arg Ser Cys Gly Cys Arg 35 117 39 PRT Homo
sapiens 2447 117 Asn Ser Cys Cys Val Pro Thr Glu Leu Ser Ala Ile
Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu Lys
Lys Tyr Glu Asp Met Val 20 25 30 Val Glu Ala Cys Gly Cys Arg 35 118
39 PRT Homo sapiens 2457 118 Asn Ser Cys Cys Val Pro Thr Glu Leu
Asn Ala Ile Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp Ser Ser Asn Val
Ile Leu Lys Lys Tyr Glu Asp Met Val 20 25 30 Val Glu Ala Cys Gly
Cys Arg 35 119 39 PRT Homo sapiens 2456 119 Lys Pro Cys Cys Ala Pro
Thr Glu Leu Ser Ala Ile Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp Ser
Ser Asn Val Ile Leu Lys Lys Tyr Glu Asp Met Val 20 25 30 Val Glu
Ala Cys Gly Cys Arg 35 120 39 PRT Homo sapiens 2460 120 Lys Pro Cys
Cys Ala Pro Thr Gln Leu Ser Ala Ile Ser Val Leu Tyr 1 5 10 15 Phe
Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Glu Asp Met Val 20 25
30 Val Glu Ala Cys Gly Cys Arg 35 121 39 PRT Homo sapiens 2449 121
Lys Pro Cys Cys Ala Pro Thr Glu Leu Asn Ala Ile Ser Val Leu Tyr 1 5
10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr Arg Asn Met
Val 20 25 30 Val Arg Ala Cys Gly Cys Arg 35 122 39 PRT Homo sapiens
2467 122 Lys Pro Cys Cys Ala Pro Thr Glu Leu Ser Ala Ile Ser Val
Leu Tyr 1 5 10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu Lys Lys Tyr
Arg Asn Met Val 20 25 30 Val Arg Ala Cys Gly Cys Arg 35 123 39 PRT
Homo sapiens 2464 123 Lys Pro Cys Cys Ala Pro Thr Gln Leu Ser Ala
Ile Ser Val Leu Tyr 1 5 10 15 Phe Asp Asp Ser Ser Asn Val Ile Leu
Lys Lys Tyr Arg Asn Met Val 20 25 30 Val Arg Ala Cys Gly Cys Arg 35
124 15 PRT Homo sapiens BMP-2 N-Terminus 124 Met Gln Ala Lys His
Lys Gln Arg Lys Arg Leu Lys Ser Ser Cys 1 5 10 15
* * * * *