U.S. patent application number 11/061452 was filed with the patent office on 2005-07-07 for isolated human drug-metabolizing proteins, nucleic acid molecules encoding human drug-metabolizing proteins, and uses thereof.
This patent application is currently assigned to APPLERA CORPORATION. Invention is credited to Beasley, Ellen M., Di Francesco, Valentina, Guegler, Karl, Ketchum, Karen A..
Application Number | 20050148013 11/061452 |
Document ID | / |
Family ID | 26942772 |
Filed Date | 2005-07-07 |
United States Patent
Application |
20050148013 |
Kind Code |
A1 |
Guegler, Karl ; et
al. |
July 7, 2005 |
Isolated human drug-metabolizing proteins, nucleic acid molecules
encoding human drug-metabolizing proteins, and uses thereof
Abstract
The present invention provides amino acid sequences of peptides
that are encoded by genes within the human genome, the
drug-metabolizing enzyme peptides of the present invention. The
present invention specifically provides isolated peptide and
nucleic acid molecules, methods of identifying orthologs and
paralogs of the drug-metabolizing enzyme peptides, and methods of
identifying modulators of the drug-metabolizing enzyme
peptides.
Inventors: |
Guegler, Karl; (Menlo Park,
CA) ; Ketchum, Karen A.; (Germantown, MD) ; Di
Francesco, Valentina; (Rockville, MD) ; Beasley,
Ellen M.; (Darnestown, MD) |
Correspondence
Address: |
CELERA GENOMICS
ATTN: WAYNE MONTGOMERY, VICE PRES, INTEL PROPERTY
45 WEST GUDE DRIVE
C2-4#20
ROCKVILLE
MD
20850
US
|
Assignee: |
APPLERA CORPORATION
Norwalk
CT
|
Family ID: |
26942772 |
Appl. No.: |
11/061452 |
Filed: |
February 22, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11061452 |
Feb 22, 2005 |
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10798414 |
Mar 12, 2004 |
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6875597 |
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10798414 |
Mar 12, 2004 |
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10162639 |
Jun 6, 2002 |
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6730505 |
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10162639 |
Jun 6, 2002 |
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09735935 |
Dec 14, 2000 |
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6420150 |
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60252895 |
Nov 27, 2000 |
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Current U.S.
Class: |
435/6.11 ;
435/183; 435/184; 435/320.1; 435/325; 435/6.14; 435/69.1;
530/388.26; 536/23.2 |
Current CPC
Class: |
A61P 15/00 20180101;
A61P 1/00 20180101; A61P 1/18 20180101; A61P 43/00 20180101; A61K
38/00 20130101; A61P 9/00 20180101; A01K 2217/05 20130101; A61P
1/16 20180101; A61P 25/00 20180101; C12N 9/13 20130101; A61P 11/00
20180101 |
Class at
Publication: |
435/006 ;
435/069.1; 435/184; 435/320.1; 435/325; 530/388.26; 536/023.2;
435/183 |
International
Class: |
C12Q 001/68; C07H
021/04; C12N 009/00; C12N 009/99; C12N 009/10 |
Claims
That which is claimed is:
1. An isolated peptide consisting of an amino acid sequence
selected from the group consisting of: (a) an amino acid sequence
shown in SEQ ID NO:2; (b) an amino acid sequence of an allelic
variant of an amino acid sequence shown in SEQ ID NO:2, wherein
said allelic variant is encoded by a nucleic acid molecule that
hybridizes under stringent conditions to the opposite strand of a
nucleic acid molecule shown in SEQ ID NOS:1 or 3; (c) an amino acid
sequence of an ortholog of an amino acid sequence shown in SEQ ID
NO:2, wherein said ortholog is encoded by a nucleic acid molecule
that hybridizes under stringent conditions to the opposite strand
of a nucleic acid molecule shown in SEQ ID NOS:1 or 3; and (d) a
fragment of an amino acid sequence shown in SEQ ID NO:2, wherein
said fragment comprises at least 10 contiguous amino acids.
2. An isolated peptide comprising an amino acid sequence selected
from the group consisting of: (a) an amino acid sequence shown in
SEQ ID NO:2; (b) an amino acid sequence of an allelic variant of an
amino acid sequence shown in SEQ ID NO:2, wherein said allelic
variant is encoded by a nucleic acid molecule that hybridizes under
stringent conditions to the opposite strand of a nucleic acid
molecule shown in SEQ ID NOS:1 or 3; (c) an amino acid sequence of
an ortholog of an amino acid sequence shown in SEQ ID NO:2, wherein
said ortholog is encoded by a nucleic acid molecule that hybridizes
under stringent conditions to the opposite strand of a nucleic acid
molecule shown in SEQ ID NOS:1 or 3; and (d) a fragment of an amino
acid sequence shown in SEQ ID NO:2, wherein said fragment comprises
at least 10 contiguous amino acids.
3. An isolated antibody that selectively binds to a peptide of
claim 2.
4. An isolated nucleic acid molecule consisting of a nucleotide
sequence selected from the group consisting of: (a) a nucleotide
sequence that encodes an amino acid sequence shown in SEQ ID NO:2;
(b) a nucleotide sequence that encodes of an allelic variant of an
amino acid sequence shown in SEQ ID NO:2, wherein said nucleotide
sequence hybridizes under stringent conditions to the opposite
strand of a nucleic acid molecule shown in SEQ ID NOS:1 or 3; (c) a
nucleotide sequence that encodes an ortholog of an amino acid
sequence shown in SEQ ID NO:2, wherein said nucleotide sequence
hybridizes under stringent conditions to the opposite strand of a
nucleic acid molecule shown in SEQ ID NOS:1 or 3; (d) a nucleotide
sequence that encodes a fragment of an amino acid sequence shown in
SEQ ID NO:2, wherein said fragment comprises at least 10 contiguous
amino acids; and (e) a nucleotide sequence that is the complement
of a nucleotide sequence of (a)-(d).
5. An isolated nucleic acid molecule comprising a nucleotide
sequence selected from the group consisting of: (a) a nucleotide
sequence that encodes an amino acid sequence shown in SEQ ID NO:2;
(b) a nucleotide sequence that encodes of an allelic variant of an
amino acid sequence shown in SEQ ID NO:2, wherein said nucleotide
sequence hybridizes under stringent conditions to the opposite
strand of a nucleic acid molecule shown in SEQ ID NOS:1 or 3; (c) a
nucleotide sequence that encodes an ortholog of an amino acid
sequence shown in SEQ ID NO:2, wherein said nucleotide sequence
hybridizes under stringent conditions to the opposite strand of a
nucleic acid molecule shown in SEQ ID NOS:1 or 3; (d) a nucleotide
sequence that encodes a fragment of an amino acid sequence shown in
SEQ ID NO:2, wherein said fragment comprises at least 10 contiguous
amino acids; and (e) a nucleotide sequence that is the complement
of a nucleotide sequence of (a)-(d).
6. A gene chip comprising a nucleic acid molecule of claim 5.
7. A transgenic non-human animal comprising a nucleic acid molecule
of claim 5.
8. A nucleic acid vector comprising a nucleic acid molecule of
claim 5.
9. A host cell containing the vector of claim 8.
10. A method for producing any of the peptides of claim 1
comprising introducing a nucleotide sequence encoding any of the
amino acid sequences in (a)-(d) into a host cell, and culturing the
host cell under conditions in which the peptides are expressed from
the nucleotide sequence.
11. A method for producing any of the peptides of claim 2
comprising introducing a nucleotide sequence encoding any of the
amino acid sequences in (a)-(d) into a host cell, and culturing the
host cell under conditions in which the peptides are expressed from
the nucleotide sequence.
12. A method for detecting the presence of any of the peptides of
claim 2 in a sample, said method comprising contacting said sample
with a detection agent that specifically allows detection of the
presence of the peptide in the sample and then detecting the
presence of the peptide.
13. A method for detecting the presence of a nucleic acid molecule
of claim 5 in a sample, said method comprising contacting the
sample with an oligonucleotide that hybridizes to said nucleic acid
molecule under stringent conditions and determining whether the
oligonucleotide binds to said nucleic acid molecule in the
sample.
14. A method for identifying a modulator of a peptide of claim 2,
said method comprising contacting said peptide with an agent and
determining if said agent has modulated the function or activity of
said peptide.
15. The method of claim 14, wherein said agent is administered to a
host cell comprising an expression vector that expresses said
peptide.
16. A method for identifying an agent that binds to any of the
peptides of claim 2, said method comprising contacting the peptide
with an agent and assaying the contacted mixture to determine
whether a complex is formed with the agent bound to the
peptide.
17. A pharmaceutical composition comprising an agent identified by
the method of claim 16 and a pharmaceutically acceptable carrier
therefor.
18. A method for treating a disease or condition mediated by a
human drug-metabolizing enzyme protein, said method comprising
administering to a patient a pharmaceutically effective amount of
an agent identified by the method of claim 16.
19. A method for identifying a modulator of the expression of a
peptide of claim 2, said method comprising contacting a cell
expressing said peptide with an agent, and determining if said
agent has modulated the expression of said peptide.
20. An isolated human drug-metabolizing enzyme peptide having an
amino acid sequence that shares at least 70% homology with an amino
acid sequence shown in SEQ ID NO:2.
21. A peptide according to claim 20 that shares at least 90 percent
homology with an amino acid sequence shown in SEQ ID NO:2.
22. An isolated nucleic acid molecule encoding a human
drug-metabolizing enzyme peptide, said nucleic acid molecule
sharing at least 80 percent homology with a nucleic acid molecule
shown in SEQ ID NOS:1 or 3.
23. A nucleic acid molecule according to claim 22 that shares at
least 90 percent homology with a nucleic acid molecule shown in SEQ
ID NOS:1 or 3.
Description
FIELD OF THE INVENTION
[0001] The present invention is in the field of drug-metabolizing
proteins that are related to the sulfotransferase drug-metabolizing
enzyme subfamily, recombinant DNA molecules and protein production.
The present invention specifically provides novel drug-metabolizing
peptides and proteins and nucleic acid molecules encoding such
protein molecules, for use in the development of human therapeutics
and human therapeutic development.
BACKGROUND OF THE INVENTION
[0002] Drug-Metabolizing Proteins
[0003] Induction of drug-metabolizing enzymes ("DMEs") is a common
biological response to xenobiotics, the mechanisms and consequences
of which are important in academic, industrial, and regulatory
areas of pharmacology and toxicology.
[0004] For most drugs, drug-metabolizing enzymes determine how long
and how much of a drug remains in the body. Thus, developers of
drugs recognize the importance of characterizing a drug candidate's
interaction with these enzymes. For example, polymorphisms of the
drug-metabolizing enzyme CYP2D6, a member of the cytochrome p450
("CYP") superfamily, yield phenotypes of slow or ultra-rapid
metabolizers of a wide spectrum of drugs including antidepressants,
antipsychotics, beta-blockers, and antiarrhythmics. Such abnormal
rates of drug metabolism can lead to drug ineffectiveness or to
systemic accumulation and toxicity.
[0005] For pharmaceutical scientists developing a candidate drug,
it is important know as early as possible in the design phase which
enzymes metabolize the drug candidate and the speed with which they
do it. Historically, the enzymes on a drug's metabolic pathway were
determined through metabolism studies in animals, but this approach
has now been largely supplanted by the use of human tissues or
cloned drug-metabolizing enzymes to provide insights into the
specific role of individual forms of these enzymes. Using these
tools, the qualitative and quantitative fate of a drug candidate
can be predicted prior to its first administration to humans. As a
consequence, the selection and optimization of desirable
characteristics of metabolism are possible early in the development
process, thus avoiding unanticipated toxicity problems and
associated costs subsequent to the drug's clinical investigation.
Moreover, the effect of one drug on another's disposition can be
inferred.
[0006] Known drug-metabolizing enzymes include the cytochrome p450
("CYP") superfamily, N-acetyl transferases ("NAT"),
UDP-glucuronosyl transferases ("UGT"), methyl transferases, alcohol
dehydrogenase ("ADH"), aldehyde dehydrogenase ("ALDH"),
dihydropyrimidine dehydrogenase ("DPD"), NADPH:quinone
oxidoreductase ("NQO" or "DT diaphorase"), catechol
O-methyltransferase ("COMT"), glutathione S-transferase ("GST"),
histamine methyltransferase ("HMT"), sulfotransferases ("ST"),
thiopurine methyltransferase ("TPMT"), and epoxide hydroxylase.
Drug-metabolizing enzymes are generally classified into two phases
according to their metabolic function. Phase I enzymes catalyze
modification of functional groups, and phase II enzymes catalyze
conjugation with endogenous substituents. These classifications
should not be construed as exclusive nor exhaustive, as other
mechanisms of drug metabolism have been discovered. For example,
the use of active transport mechanisms been characterized as part
of the process of detoxification.
[0007] Phase I reactions include catabolic processes such as
deamination of aminases, hydrolysis of esters and amides,
conjugation reactions with, for example, glycine or sulfate,
oxidation by the cytochrome p450 oxidation/reduction enzyme system
and degradation in the fatty acid pathway. Hydrolysis reactions
occur mainly in the liver and plasma by a variety of non-specific
hydrolases and esterases. Both deaminases and amidases, also
localized in the liver and serum, carry out a large part of the
catabolic process. Reduction reactions occur mainly intracellularly
in the endoplasmic reticulum.
[0008] Phase II enzymes detoxify toxic substances by catalyzing
their conjugation with water-soluble substances, thus increasing
toxins' solubility in water and increasing their rate of excretion.
Additionally, conjugation reduces the toxins' biological
reactivity. Examples of phase II enzymes include glutathione
S-transferases and UDP-glucuronosyl transferases, which catalyze
conjugation to glutathione and glucuronic acid, respectively.
Transferases perform conjugation reactions mainly in the kidneys
and liver.
[0009] The liver is the primary site of elimination of most drugs,
including psychoactive drugs, and contains a plurality of both
phase I and phase II enzymes that oxidize or conjugate drugs,
respectively.
[0010] Physicians currently prescribe drugs and their dosages based
on a population average and fail to take genetic variability into
account. The variability between individuals in drug metabolism is
usually due to both genetic and environmental factors, in
particular, how the drug-metabolizing enzymes are controlled. With
certain enzymes, the genetic component predominates and variability
is associated with variants of the normal, wild-type enzyme.
[0011] Most drug-metabolizing enzymes exhibit clinically relevant
genetic polymorphisms. Essentially all of the major human enzymes
responsible for modification of functional groups or conjugation
with endogenous subsituents exhibit common polymorphisms at the
genomic level. For example, polymorphisms expressing a
non-functioning variant enzyme results in a sub-group of patients
in the population who are more prone to the concentration-dependent
effects of a drug. This sub-group of patients may show toxic side
effects to a dose of drug that is otherwise without side effects in
the general population. Recent development in genotyping allows
identification of affected individuals. As a result, their atypical
metabolism and likely response to a drug metabolized by the
affected enzyme can be understood and predicted, thus permitting
the physician to adjust the dose of drug they receive to achieve
improved therapy.
[0012] A similar approach is also becoming important in identifying
risk factors associated with the development of various cancers.
This is because the enzymes involved in drug metabolism are also
responsible for the activation and detoxification of chemical
carcinogens. Specifically, the development of neoplasia is
regulated by a balance between phase I enzymes, which activate
carcinogens, and phase II enzymes, which detoxify them.
Accordingly, an individual's susceptibility to cancer often
involves the balance between these two processes, which is, in
part, genetically determined and can be screened by suitable
genotyping tests. Higher induction of phase I enzymes compared to
phase II enzymes results in the generation of large amounts of
electrophiles and reactive oxygen species and may cause DNA and
membrane damage and other adverse effects leading to neoplasia.
Conversely, higher levels of phase II enzyme expression can protect
cells from various chemical compounds.
[0013] Abnormal activity of drug-metabolizing enzymes has been
implicated in a range of human diseases, including cancer,
Parkinson's disease, myetonic dystrophy, and developmental
defects.
[0014] Cytochrome p450
[0015] An example of a phase I drug-metabolizing enzyme is the
cytochrome p450 ("CYP") superfamily, the members of which comprise
the major drug-metabolizing enzymes expressed in the liver. The CYP
superfamily comprises heme proteins which catalyze the oxidation
and dehydrogenation of a number of endogenous and exogenous
lipophilic compounds. The CYP superfamily has immense diversity in
its functions, with hundreds of isoforms in many species catalyzing
many types of chemical reactions. The CYP superfamily comprises at
least 30 related enzymes, which are divided into different families
according to their amino acid homology. Examples of CYP families
include CYP families 1, 2, 3 and 4, which comprise endoplasmic
reticulum proteins responsible for the metabolism of drugs and
other xenobiotics. Approximately 10-15 individual gene products
within these four families metabolize thousands of structurally
diverse compounds. It is estimated that collectively the enzymes in
the CYP superfamily participate in the metabolism of greater than
80% of all available drugs used in humans. For example, the CYP 1A
subfamily comprises CYP 1A2, which metabolizes several widely used
drugs, including acetaminophen, amitriptyline, caffeine, clozapine,
haloperidol, imipramine, olanzapine, ondansetron, phenacetin,
propafenone, propranolol, tacrine, theophylline, verapamil. In
addition, CYP enzymes play additional roles in the metabolism of
some endogenous substrates including prostaglandins and
steroids.
[0016] Some CYP enzymes exist in a polymorphic form, meaning that a
small percentage of the population possesses mutant genes that
alter the activity of the enzyme, usually by diminishing or
abolishing activity. For example, a genetic polymorphism has been
well characterized with the CYP 2Cl9 and CYP 2D6 genes. Substrates
of CYP 2C19 include clomipramine, diazepam, imipramine,
mephenytoin, moclobemide, omeprazole, phenytoin, propranolol, and
tolbutamide. Substrates of CYP 2D6 include alprenolol,
amitriptyline, chlorpheniramine, clomipramine, codeine,
desipramine, dextromethorphan, encainide, fluoxetine, haloperidol,
imipramine, indoramin, metoprolol, nortriptyline, ondansetron,
oxycodone, paroxetine, propranolol, and propafenone. Polymorphic
variants of these genes metabolize these substrates at different
rates, which can effect a patient's effective therapeutic
dosage.
[0017] While the substrate specificity of CYPs must be very broad
to accommodate the metabolism of all of these compounds, each
individual CYP gene product has a narrower substrate specificity
defined by its binding and catalytic sites. Drug metabolism can
thereby be regulated by changes in the amount or activity of
specific CYP gene products. Methods of CYP regulation include
genetic differences in the expression of CYP gene products (i.e.,
genetic polymorphisms), inhibition of CYP metabolism by other
xenobiotics that also bind to the CYP, and induction of certain
CYPs by the drug itself or other xenobiotics. Inhibition and
induction of CYPs is one of the most common mechanisms of adverse
drug interactions. For example, the CYP3A subfamily is involved in
clinically significant drug interactions involving nonsedating
antihistamines and cisapride that may result in cardiac
dysrhythmias. In another example, CYP3A4 and CYP1A2 enzymes are
involved in drug interactions involving theophylline. In yet
another example, CYP2D6 is responsible for the metabolism of many
psychotherapeutic agents. Additionallly, CYP enzymes metabolize the
protease inhibitors used to treat patients infected with the human
immunodeficiency virus. By understanding the unique functions and
characteristics of these enzymes, physicians may better anticipate
and manage drug interactions and may predict or explain an
individual's response to a particular therapeutic regimen.
[0018] Examples of reactions catalyzed by the CYP superfamily
include peroxidative reactions utilizing peroxides as oxygen donors
in hydroxylation reactions, as substrates for reductive
beta-scission, and as peroxyhemiacetal intermediates in the
cleavage of aldehydes to formate and alkenes. Lipid hydroperoxides
undergo reductive beta-cleavage to give hydrocarbons and aldehydic
acids. One of these products, trans4-hydroxynonenal, inactivates
CYP, particularly alcohol-inducible 2E1, in what may be a negative
regulatory process. Although a CYP iron-oxene species is believed
to be the oxygen donor in most hydroxylation reactions, an
iron-peroxy species is apparently involved in the deformylation of
many aldehydes with desaturation of the remaining structure, as in
aromatization reactions.
[0019] Examples of drugs with oxidative metabolism associated with
CYP enzymes include acetaminophen, alfentanil, alprazolam,
alprenolol, amiodarone, amitriptyline, astemizole, buspirone
caffeine, carbamazepine, chlorpheniramine, cisapride, clomipramine,
clomipramine, clozapine, codeine, colchicine, cortisol,
cyclophosphamide, cyclosporine, dapsone, desipramine,
dextromethorphan, diazepam, diclofenac, diltiazem, encainide,
erythromycin, estradiol, felodipine, fluoxetine, fluvastatin,
haloperidol, ibuprofen, imipramine, indinavir, indomethacin,
indoramin, irbesartan, lidocaine, losartan, macrolide antibiotics,
mephenytoin, methadone, metoprolol, mexilitene, midazolam,
moclobemide, naproxen, nefazodone, nicardipine, nifedipine,
nitrendipine, nortriptyline, olanzapine, omeprazole, ondansetron,
oxycodone, paclitaxel, paroxetine, phenacetin, phenytoin,
piroxicam, progesterone, propafenone, propranolol, quinidine,
ritonavir, saquinavir, sertraline, sildenafil, S-warfarin, tacrine,
tamoxifen, tenoxicam, terfenadine, testosterone, theophylline,
timolol, tolbutamide, triazolam, verapamil, and vinblastine.
[0020] Abnormal activity of phase I enzymes has been implicated in
a range of human diseases. For example, enhanced CYP2D6 activity
has been related to malignancies of the bladder, liver, pharynx,
stomach and lungs, whereas decreased CYP2D activity has been linked
to an increased risk of Parkinson's disease. Other syndromes and
developmental defects associated with deficiencies in the CYP
superfamily include cerebrotendinous xanthomatosis, adrenal
hyperplasia, gynecomastia, and myetonic dystrophy.
[0021] The CYP superfamily a major target for drug action and
development. Accordingly, it is valuable to the field of
pharmaceutical development to identify and characterize previously
unknown members of the CYP superfamily.
[0022] UDP-Glucuronosyltransferases
[0023] Potential drug interactions involving phase II metabolism
are increasingly being recognized. An important group of phase II
enzymes involved in drug metabolism are the
glucuronosyltransferases, especially the UDP-glucuronyltransferase
("UGT") superfamily. Members of the UGT superfamily catalyze the
enzymatic addition of UDP glucuronic acid as a sugar donor to
fat-soluble chemicals, a process which increases their solubility
in water and increases their rate of excretion. In mammals,
glucuronic acid is the main sugar that is used to prevent the
accumulation of waste products of metabolism and fat-soluble
chemicals from the environment to toxic levels in the body. Both
inducers and inhibitors of glucuronosyltransferases are known and
have the potential to affect the plasma concentration and actions
of important drugs, including psychotropic drugs.
[0024] The UGT superfamily comprises several families of enzymes in
several species defined with a nomenclature similar to that used to
define members of the CYP superfamily. In animals, yeast, plants
and bacteria there are at least 110 distinct known members of the
UGT superfamily. As many as 33 families have been defined, with
three families identified in humans. Different UGT families are
defined as having <45% amino acid sequence homology; within
subfamilies there is approximately 60% homology. The members of the
UGT superfamily are part of a further superfamily of UDP
glycosyltransferases found in animals, plants and bacteria.
[0025] The role of phase II enzymes, and of UGT enzymes in
particular, is being increasingly recognized as important in
psychopharmacology. UGT enzymes conjugate many important
psychotropic drugs and are an important source of variability in
drug response and drug interactions. For example, the
benzodiazepines lorazepam, oxazepam, and temazepam undergo phase II
reactions exclusively before being excreted into the urine.
[0026] Phase II enzymes metabolize and detoxify hazardous
substances, such as carcinogens. The expression of genes encoding
phase II enzymes is known to be up-regulated by hundreds of agents.
For example, oltipraz is known to up-regulate phase II enzyme
expression. Studies have demonstrated protection from the
cancer-causing effects of carcinogens when selected phase II enzyme
inducers are administered prior to the carcinogens. The potential
use of phase II enzyme inducers in humans for prevention of cancers
related to exposure to carcinogens has prompted studies aimed at
understanding their molecular effects. Current biochemical and
molecular biological research methodologies can be used to identify
and characterize selective phase II enzyme inducers and their
targets. Identification of genes responding to cancer
chemopreventive agents will facilitate studies of their basic
mechanism and provide insights about the relationship between gene
regulation, enzyme polymorphism, and carcinogen detoxification.
[0027] Examples of drugs with conjugative metabolism associated
with UGT enzymes include amitriptyline, buprenorphine,
chlorpromazine, clozapine, codeine, cyproheptadine, dihydrocodeine,
doxepin, imipramine, lamotrigine, lorazepam, morphine, nalorphine,
naltrexone, temazepam, and valproate.
[0028] Abnormal activity of phase II enzymes has been implicated in
a range of human diseases. For example, Gilbert syndrome is an
autosomal dominant disorder caused by mutation in the UGT1 gene,
and mutations in the UGT1A1 enzyme have been demonstrated to be
responsible for Crigler-Najjar syndrome.
[0029] The UGT superfamily a major target for drug action and
development. Accordingly, it is valuable to the field of
pharmaceutical development to identify and characterize previously
unknown members of the UGT superfamily.
[0030] Sulfotransferase
[0031] The sulfotransferases that act upon different substrates
exhibit extensive structural diversity; indeed, similarity is
greatest between members of this enzyme class that sulfate related
substrates. The sulfotransferase includes the
N-acetylglucosamine/glucuronic acid copolymerase, the
N-deacetylase/N-sulfotransferase (NST), the glucuronic
acid/iduronic acid epimerase, the iduronic acid/glucuronic acid
2-O-sulfotransferase, the glucosamine 6-O-sulfotransferase, and the
glucosamine 3-O-sulfotransferase (3-OST). 3-OST and all known NST
species possess a homologous carboxyl-terminal domain of .about.260
residues that also exhibits homology to all known
sulfotransferases. Given that this region constitutes >88% of
the protein A-tagged r3-OST and so should contain the machinery for
sulfation, that a common domain structure is shared by heparan
sulfate sulfotransferases or at least by heparan glucosaminyl
sulfotransferases. The cellular rate of anticoagulant heparan
sulfate proteoglycan generation is determined by the level of the
microsomal activity `HS-act conversion activity`, which is
predominantly composed of the enzyme heparan sulfate D-glucosaminyl
3-O-sulfotransferase (3OST). Shworak et al., (J Biol Chem Oct. 31,
1997;272(44):28008-19) cloned mouse and human 3OST cDNAs. The
predicted 307-amino acid human 3OST protein shares 93% sequence
similarity with mouse 3OST. The 3OST protein contains a signal
sequence and 5 potential N-glycosylation sites. Both human and
mouse 3OST have a calculated molecular mass of approximately 36 kD.
The discrepancy between the observed and calculated molecular
masses is due to glycosylation. The human and mouse 3OST proteins
exhibited HS-act conversion and 3OST activities when expressed in
vitro. Based on the site of heparan biosynthesis and on structural
analysis of the 3OST protein, it is suggested that 3OST is an
intraluminal Golgi enzyme. The Northern blot analysis of human
cells showed that 3OST is expressed as a 1.7-kb mRNA.
[0032] Drug-metabolizing enzymes, particularly members of the
sulfotransferase drug-metabolizing enzyme subfamily, are a major
target for drug action and development. Accordingly, it is valuable
to the field of pharmaceutical development to identify and
characterize previously unknown members of this subfamily of
drug-metabolizing proteins. The present invention advances the
state of the art by providing a previously unidentified human
drug-metabolizing proteins that have homology to members of the
sulfotransferase drug-metabolizing enzyme subfamily.
SUMMARY OF THE INVENTION
[0033] The present invention is based in part on the identification
of amino acid sequences of human drug-metabolizing enzyme peptides
and proteins that are related to the sulfotransferase
drug-metabolizing enzyme subfamily, as well as allelic variants and
other mammalian orthologs thereof. These unique peptide sequences,
and nucleic acid sequences that encode these peptides, can be used
as models for the development of human therapeutic targets, aid in
the identification of therapeutic proteins, and serve as targets
for the development of human therapeutic agents that modulate
drug-metabolizing enzyme activity in cells and tissues that express
the drug-metabolizing enzyme. Experimental data as provided in FIG.
1 indicates expression in the lung.
DESCRIPTION OF THE FIGURE SHEETS
[0034] FIG. 1 provides the nucleotide sequence of a cDNA molecule
or transcript sequence that encodes the drug-metabolizing enzyme
protein of the present invention. (SEQ ID NO:1) In addition,
structure and functional information is provided, such as ATG
start, stop and tissue distribution, where available, that allows
one to readily determine specific uses of inventions based on this
molecular sequence. Experimental data as provided in FIG. 1
indicates expression in the lung.
[0035] FIG. 2 provides the predicted amino acid sequence of the
drug-metabolizing enzyme of the present invention. (SEQ ID NO:2) In
addition structure and functional information such as protein
family, function, and modification sites is provided where
available, allowing one to readily determine specific uses of
inventions based on this molecular sequence.
[0036] FIG. 3 provides genomic sequences that span the gene
encoding the drug-metabolizing enzyme protein of the present
invention. (SEQ ID NO:3) In addition structure and functional
information, such as intron/exon structure, promoter location,
etc., is provided where available, allowing one to readily
determine specific uses of inventions based on this molecular
sequence. 4 SNPs have been identified in the gene encoding the
sulfotransferase protein provided by the present invention and are
given in FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
[0037] General Description
[0038] The present invention is based on the sequencing of the
human genome. During the sequencing and assembly of the human
genome, analysis of the sequence information revealed previously
unidentified fragments of the human genome that encode peptides
that share structural and/or sequence homology to
protein/peptide/domains identified and characterized within the art
as being a drug-metabolizing enzyme protein or part of a
drug-metabolizing enzyme protein and are related to the
sulfotransferase drug-metabolizing enzyme subfamily. Utilizing
these sequences, additional genomic sequences were assembled and
transcript and/or cDNA sequences were isolated and characterized.
Based on this analysis, the present invention provides amino acid
sequences of human drug-metabolizing enzyme peptides and proteins
that are related to the sulfotransferase drug-metabolizing enzyme
subfamily, nucleic acid sequences in the form of transcript
sequences, cDNA sequences and/or genomic sequences that encode
these drug-metabolizing enzyme peptides and proteins, nucleic acid
variation (allelic information), tissue distribution of expression,
and information about the closest art known protein/peptide/domain
that has structural or sequence homology to the drug-metabolizing
enzyme of the present invention.
[0039] In addition to being previously unknown, the peptides that
are provided in the present invention are selected based on their
ability to be used for the development of commercially important
products and services. Specifically, the present peptides are
selected based on homology and/or structural relatedness to known
drug-metabolizing enzyme proteins of the sulfotransferase
drug-metabolizing enzyme subfamily and the expression pattern
observed. Experimental data as provided in FIG. 1 indicates
expression in the lung. The art has clearly established the
commercial importance of members of this family of proteins and
proteins that have expression patterns similar to that of the
present gene. Some of the more specific features of the peptides of
the present invention, and the uses thereof, are described herein,
particularly in the Background of the Invention and in the
annotation provided in the Figures, and/or are known within the art
for each of the known sulfotransferase family or subfamily of
drug-metabolizing enzyme proteins.
[0040] Specific Embodiments
[0041] Peptide Molecules
[0042] The present invention provides nucleic acid sequences that
encode protein molecules that have been identified as being members
of the drug-metabolizing enzyme family of proteins and are related
to the sulfotransferase drug-metabolizing enzyme subfamily (protein
sequences are provided in FIG. 2, transcript/cDNA sequences are
provided in FIG. 1 and genomic sequences are provided in FIG. 3).
The peptide sequences provided in FIG. 2, as well as the obvious
variants described herein, particularly allelic variants as
identified herein and using the information in FIG. 3, will be
referred herein as the drug-metabolizing enzyme peptides of the
present invention, drug-metabolizing enzyme peptides, or
peptides/proteins of the present invention.
[0043] The present invention provides isolated peptide and protein
molecules that consist of, consist essentially of, or comprise the
amino acid sequences of the drug-metabolizing enzyme peptides
disclosed in the FIG. 2, (encoded by the nucleic acid molecule
shown in FIG. 1, transcript/cDNA or FIG. 3, genomic sequence), as
well as all obvious variants of these peptides that are within the
art to make and use. Some of these variants are described in detail
below.
[0044] As used herein, a peptide is said to be "isolated" or
"purified" when it is substantially free of cellular material or
free of chemical precursors or other chemicals. The peptides of the
present invention can be purified to homogeneity or other degrees
of purity. The level of purification will be based on the intended
use. The critical feature is that the preparation allows for the
desired function of the peptide, even if in the presence of
considerable amounts of other components (the features of an
isolated nucleic acid molecule is discussed below).
[0045] In some uses, "substantially free of cellular material"
includes preparations of the peptide having less than about 30% (by
dry weight) other proteins (i.e., contaminating protein), less than
about 20% other proteins, less than about 10% other proteins, or
less than about 5% other proteins. When the peptide is
recombinantly produced, it can also be substantially free of
culture medium, i.e., culture medium represents less than about 20%
of the volume of the protein preparation.
[0046] The language "substantially free of chemical precursors or
other chemicals" includes preparations of the peptide in which it
is separated from chemical precursors or other chemicals that are
involved in its synthesis. In one embodiment, the language
"substantially free of chemical precursors or other chemicals"
includes preparations of the drug-metabolizing enzyme peptide
having less than about 30% (by dry weight) chemical precursors or
other chemicals, less than about 20% chemical precursors or other
chemicals, less than about 10% chemical precursors or other
chemicals, or less than about 5% chemical precursors or other
chemicals.
[0047] The isolated drug-metabolizing enzyme peptide can be
purified from cells that naturally express it, purified from cells
that have been altered to express it (recombinant), or synthesized
using known protein synthesis methods. Experimental data as
provided in FIG. 1 indicates expression in the lung. For example, a
nucleic acid molecule encoding the drug-metabolizing enzyme peptide
is cloned into an expression vector, the expression vector
introduced into a host cell and the protein expressed in the host
cell. The protein can then be isolated from the cells by an
appropriate purification scheme using standard protein purification
techniques. Many of these techniques are described in detail
below.
[0048] Accordingly, the present invention provides proteins that
consist of the amino acid sequences provided in FIG. 2 (SEQ ID
NO:2), for example, proteins encoded by the transcript/cDNA nucleic
acid sequences shown in FIG. 1 (SEQ ID NO:1) and the genomic
sequences provided in FIG. 3 (SEQ ID NO:3). The amino acid sequence
of such a protein is provided in FIG. 2. A protein consists of an
amino acid sequence when the amino acid sequence is the final amino
acid sequence of the protein.
[0049] The present invention further provides proteins that consist
essentially of the amino acid sequences provided in FIG. 2 (SEQ ID
NO:2), for example, proteins encoded by the transcript/cDNA nucleic
acid sequences shown in FIG. 1 (SEQ ID NO:1) and the genomic
sequences provided in FIG. 3 (SEQ ID NO:3). A protein consists
essentially of an amino acid sequence when such an amino acid
sequence is present with only a few additional amino acid residues,
for example from about 1 to about 100 or so additional residues,
typically from I to about 20 additional residues in the final
protein.
[0050] The present invention further provides proteins that
comprise the amino acid sequences provided in FIG. 2 (SEQ ID NO:2),
for example, proteins encoded by the transcript/cDNA nucleic acid
sequences shown in FIG. 1 (SEQ ID NO:1) and the genomic sequences
provided in FIG. 3 (SEQ ID NO:3). A protein comprises an amino acid
sequence when the amino acid sequence is at least part of the final
amino acid sequence of the protein. In such a fashion, the protein
can be only the peptide or have additional amino acid molecules,
such as amino acid residues (contiguous encoded sequence) that are
naturally associated with it or heterologous amino acid
residues/peptide sequences. Such a protein can have a few
additional amino acid residues or can comprise several hundred or
more additional amino acids. The preferred classes of proteins that
are comprised of the drug-metabolizing enzyme peptides of the
present invention are the naturally occurring mature proteins. A
brief description of how various types of these proteins can be
made/isolated is provided below.
[0051] The drug-metabolizing enzyme peptides of the present
invention can be attached to heterologous sequences to form
chimeric or fusion proteins. Such chimeric and fusion proteins
comprise a drug-metabolizing enzyme peptide operatively linked to a
heterologous protein having an amino acid sequence not
substantially homologous to the drug-metabolizing enzyme peptide.
"Operatively linked" indicates that the drug-metabolizing enzyme
peptide and the heterologous protein are fused in-frame. The
heterologous protein can be fused to the N-terminus or C-terminus
of the drug-metabolizing enzyme peptide.
[0052] In some uses, the fusion protein does not affect the
activity of the drug-metabolizing enzyme peptide per se. For
example, the fusion protein can include, but is not limited to,
enzymatic fusion proteins, for example beta-galactosidase fusions,
yeast two-hybrid GAL fusions, poly-His fusions, MYC-tagged,
HI-tagged and Ig fusions. Such fusion proteins, particularly
poly-His fusions, can facilitate the purification of recombinant
drug-metabolizing enzyme peptide. In certain host cells (e.g.,
mammalian host cells), expression and/or secretion of a protein can
be increased by using a heterologous signal sequence.
[0053] A chimeric or fusion protein can be produced by standard
recombinant DNA techniques. For example, DNA fragments coding for
the different protein sequences are ligated together in-frame in
accordance with conventional techniques. In another embodiment, the
fusion gene can be synthesized by conventional techniques including
automated DNA synthesizers. Alternatively, PCR amplification of
gene fragments can be carried out using anchor primers which give
rise to complementary overhangs between two consecutive gene
fragments which can subsequently be annealed and re-amplified to
generate a chimeric gene sequence (see Ausubel et al., Current
Protocols in Molecular Biology, 1992). Moreover, many expression
vectors are commercially available that already encode a fusion
moiety (e.g., a GST protein). A drug-metabolizing enzyme
peptide-encoding nucleic acid can be cloned into such an expression
vector such that the fusion moiety is linked in-frame to the
drug-metabolizing enzyme peptide.
[0054] As mentioned above, the present invention also provides and
enables obvious variants of the amino acid sequence of the proteins
of the present invention, such as naturally occurring mature forms
of the peptide, allelic/sequence variants of the peptides,
non-naturally occurring recombinantly derived variants of the
peptides, and orthologs and paralogs of the peptides. Such variants
can readily be generated using art-known techniques in the fields
of recombinant nucleic acid technology and protein biochemistry. It
is understood, however, that variants exclude any amino acid
sequences disclosed prior to the invention.
[0055] Such variants can readily be identified/made using molecular
techniques and the sequence information disclosed herein. Further,
such variants can readily be distinguished from other peptides
based on sequence and/or structural homology to the
drug-metabolizing enzyme peptides of the present invention. The
degree of homology/identity present will be based primarily on
whether the peptide is a functional variant or non-functional
variant, the amount of divergence present in the paralog family and
the evolutionary distance between the orthologs.
[0056] To determine the percent identity of two amino acid
sequences or two nucleic acid sequences, the sequences are aligned
for optimal comparison purposes (e.g., gaps can be introduced in
one or both of a first and a second amino acid or nucleic acid
sequence for optimal alignment and non-homologous sequences can be
disregarded for comparison purposes). In a preferred embodiment, at
least 30%, 40%, 50%, 60%, 70%, 80%, or 90% or more of the length of
a reference sequence is aligned for comparison purposes. The amino
acid residues or nucleotides at corresponding amino acid positions
or nucleotide positions are then compared. When a position in the
first sequence is occupied by the same amino acid residue or
nucleotide as the corresponding position in the second sequence,
then the molecules are identical at that position (as used herein
amino acid or nucleic acid "identity" is equivalent to amino acid
or nucleic acid "homology"). The percent identity between the two
sequences is a function of the number of identical positions shared
by the sequences, taking into account the number of gaps, and the
length of each gap, which need to be introduced for optimal
alignment of the two sequences.
[0057] The comparison of sequences and determination of percent
identity and similarity between two sequences can be accomplished
using a mathematical algorithm. (Computational Molecular Biology,
Lesk, A. M., ed., Oxford University Press, New York, 1988;
Biocomputing: Informatics and Genome Projects, Smith, D. W., ed.,
Academic Press, New York, 1993; Computer Analysis of Sequence Data,
Part 1, Griffin, A. M., and Griffin, H. G., eds., Humana Press, New
Jersey, 1994; Sequence Analysis in Molecular Biology, von Heinje,
G., Academic Press, 1987; and Sequence Analysis Primer, Gribskov,
M. and Devereux, J., eds., M Stockton Press, New York, 1991). In a
preferred embodiment, the percent identity between two amino acid
sequences is determined using the Needleman and Wunsch (J. Mol.
Biol. (48):444-453 (1970)) algorithm which has been incorporated
into the GAP program in the GCG software package (available at
http://www.gcg.com), using either a Blossom 62 matrix or a PAM250
matrix, and a gap weight of 16, 14, 12, 10, 8, 6, or 4 and a length
weight of 1, 2, 3, 4, 5, or 6. In yet another preferred embodiment,
the percent identity between two nucleotide sequences is determined
using the GAP program in the GCG software package (Devereux, J., et
al., Nucleic Acids Res. 12(1):387 (1984)) (available at
http://www.gcg.com), using a NWSgapdna.CMP matrix and a gap weight
of 40, 50, 60, 70, or 80 and a length weight of 1, 2, 3, 4, 5, or
6. In another embodiment, the percent identity between two amino
acid or nucleotide sequences is determined using the algorithm of
E. Myers and W. Miller (CABIOS, 4:11-17 (1989)) which has been
incorporated into the ALIGN program (version 2.0), using a PAM120
weight residue table, a gap length penalty of 12 and a gap penalty
of 4.
[0058] The nucleic acid and protein sequences of the present
invention can further be used as a "query sequence" to perform a
search against sequence databases to, for example, identify other
family members or related sequences. Such searches can be performed
using the NBLAST and XBLAST programs (version 2.0) of Altschul, et
al. (J. Mol. Biol. 215:403-10 (1990)). BLAST nucleotide searches
can be performed with the NBLAST program, score=100, wordlength=12
to obtain nucleotide sequences homologous to the nucleic acid
molecules of the invention. BLAST protein searches can be performed
with the XBLAST program, score=50, wordlength=3 to obtain amino
acid sequences homologous to the proteins of the invention. To
obtain gapped alignments for comparison purposes, Gapped BLAST can
be utilized as described in Altschul et al. (Nucleic Acids Res.
25(17):3389-3402 (1997)). When utilizing BLAST and gapped BLAST
programs, the default parameters of the respective programs (e.g.,
XBLAST and NBLAST) can be used.
[0059] Full-length pre-processed forms, as well as mature processed
forms, of proteins that comprise one of the peptides of the present
invention can readily be identified as having complete sequence
identity to one of the drug-metabolizing enzyme peptides of the
present invention as well as being encoded by the same genetic
locus as the drug-metabolizing enzyme peptide provided herein. As
indicated by the data presented in FIG. 3, the map position was
determined to be on chromosome 6 by ePCR.
[0060] Allelic variants of a drug-metabolizing enzyme peptide can
readily be identified as being a human protein having a high degree
(significant) of sequence homology/identity to at least a portion
of the drug-metabolizing enzyme peptide as well as being encoded by
the same genetic locus-as the drug-metabolizing enzyme peptide
provided herein. Genetic locus can readily be determined based on
the genomic information provided in FIG. 3, such as the genomic
sequence mapped to the reference human. As indicated by the data
presented in FIG. 3, the map position was determined to be on
chromosome 6 by ePCR. As used herein, two proteins (or a region of
the proteins) have significant homology when the amino acid
sequences are typically at least about 70-80%, 80-90%, and more
typically at least about 90-95% or more homologous. A significantly
homologous amino acid sequence, according to the present invention,
will be encoded by a nucleic acid sequence that will hybridize to a
drug-metabolizing enzyme peptide encoding nucleic acid molecule
under stringent conditions as more fully described below.
[0061] FIG. 3 provides information on SNPs that have been
identified in a gene encoding the that drug-metabolizing enzyme
proteins of the present invention. 4 SNP variants were found, of
which all of them beyond ORFs.
[0062] Paralogs of a drug-metabolizing enzyme peptide can readily
be identified as having some degree of significant sequence
homology/identity to at least a portion of the drug-metabolizing
enzyme peptide, as being encoded by a gene from humans, and as
having similar activity or function. Two proteins will typically be
considered paralogs when the amino acid sequences are typically at
least about 60% or greater, and more typically at least about 70%
or greater homology through a given region or domain. Such paralogs
will be encoded by a nucleic acid sequence that will hybridize to a
drug-metabolizing enzyme peptide encoding nucleic acid molecule
under moderate to stringent conditions as more fully described
below.
[0063] Orthologs of a drug-metabolizing enzyme peptide can readily
be identified as having some degree of significant sequence
homology/identity to at least a portion of the drug-metabolizing
enzyme peptide as well as being encoded by a gene from another
organism. Preferred orthologs will be isolated from mammals,
preferably primates, for the development of human therapeutic
targets and agents. Such orthologs will be encoded by a nucleic
acid sequence that will hybridize to a drug-metabolizing enzyme
peptide encoding nucleic acid molecule under moderate to stringent
conditions, as more fully described below, depending on the degree
of relatedness of the two organisms yielding the proteins.
[0064] Non-naturally occurring variants of the drug-metabolizing
enzyme peptides of the present invention can readily be generated
using recombinant techniques. Such variants include, but are not
limited to deletions, additions and substitutions in the amino acid
sequence of the drug-metabolizing enzyme peptide. For example, one
class of substitutions are conserved amino acid substitution. Such
substitutions are those that substitute a given amino acid in a
drug-metabolizing enzyme peptide by another amino acid of like
characteristics. Typically seen as conservative substitutions are
the replacements, one for another, among the aliphatic amino acids
Ala, Val, Leu, and Ile; interchange of the hydroxyl residues Ser
and Thr; exchange of the acidic residues Asp and Glu; substitution
between the amide residues Asn and Gln; exchange of the basic
residues Lys and Arg; and replacements among the aromatic residues
Phe and Tyr. Guidance concerning which amino acid changes are
likely to be phenotypically silent are found in Bowie et al.,
Science 247:1306-1310 (1990).
[0065] Variant drug-metabolizing enzyme peptides can be fully
functional or can lack function in one or more activities, e.g.
ability to bind substrate, ability to phosphorylate substrate,
ability to mediate signaling, etc. Fully functional variants
typically contain only conservative variation or variation in
non-critical residues or in non-critical regions. FIG. 2 provides
the result of protein analysis and can be used to identify critical
domains/regions. Functional variants can also contain substitution
of similar amino acids that result in no change or an insignificant
change in function. Alternatively, such substitutions may
positively or negatively affect function to some degree.
[0066] Non-functional variants typically contain one or more
non-conservative amino acid substitutions, deletions, insertions,
inversions, or truncation or a substitution, insertion, inversion,
or deletion in a critical residue or critical region.
[0067] Amino acids that are essential for function can be
identified by methods known in the art, such as site-directed
mutagenesis or alanine-scanning mutagenesis (Cunningham et al.,
Science 244:1081-1085 (1989)), particularly using the results
provided in FIG. 2. The latter procedure introduces single alanine
mutations at every residue in the molecule. The resulting mutant
molecules are then tested for biological activity such as
drug-metabolizing enzyme activity or in assays such as an in vitro
proliferative activity. Sites that are critical for binding
partner/substrate binding can also be determined by structural
analysis such as crystallization, nuclear magnetic resonance or
photoaffinity labeling (Smith et al., J. Mol. Biol. 224:899-904
(1992); de Vos et al. Science 255:306-312 (1992)).
[0068] The present invention further provides fragments of the
drug-metabolizing enzyme peptides, in addition to proteins and
peptides that comprise and consist of such fragments, particularly
those comprising the residues identified in FIG. 2. The fragments
to which the invention pertains, however, are not to be construed
as encompassing fragments that may be disclosed publicly prior to
the present invention.
[0069] As used herein, a fragment comprises at least 8, 10, 12, 14,
16, or more contiguous amino acid residues from a drug-metabolizing
enzyme peptide. Such fragments can be chosen based on the ability
to retain one or more of the biological activities of the
drug-metabolizing enzyme peptide or could be chosen for the ability
to perform a function, e.g. bind a substrate or act as an
immunogen. Particularly important fragments are biologically active
fragments, peptides that are, for example, about 8 or more amino
acids in length. Such fragments will typically comprise a domain or
motif of the drug-metabolizing enzyme peptide, e.g., active site, a
transmembrane domain or a substrate-binding domain. Further,
possible fragments include, but are not limited to, domain or motif
containing fragments, soluble peptide fragments, and fragments
containing immunogenic structures. Predicted domains and functional
sites are readily identifiable by computer programs well known and
readily available to those of skill in the art (e.g., PROSYE
analysis). The results of one such analysis are provided in FIG.
2.
[0070] Polypeptides often contain amino acids other than the 20
amino acids commonly referred to as the 20 naturally occurring
amino acids. Further, many amino acids, including the terminal
amino acids, may be modified by natural processes, such as
processing and other post-translational modifications, or by
chemical modification techniques well known in the art. Common
modifications that occur naturally in drug-metabolizing enzyme
peptides are described in basic texts, detailed monographs, and the
research literature, and they are well known to those of skill in
the art (some of these features are identified in FIG. 2).
[0071] Known modifications include, but are not limited to,
acetylation, acylation, ADP-ribosylation, amidation, covalent
attachment of flavin, covalent attachment of a heme moiety,
covalent attachment of a nucleotide or nucleotide derivative,
covalent attachment of a lipid or lipid derivative, covalent
attachment of phosphotidylinositol, cross-linking, cyclization,
disulfide bond formation, demethylation, formation of covalent
crosslinks, formation of cystine, formation of pyroglutamate,
formylation, gamma carboxylation, glycosylation, GPI anchor
formation, hydroxylation, iodination, methylation, myristoylation,
oxidation, proteolytic processing, phosphorylation, prenylation,
racemization, selenoylation, sulfation, transfer-RNA mediated
addition of amino acids to proteins such as arginylation, and
ubiquitination.
[0072] Such modifications are well known to those of skill in the
art and have been described in great detail in the scientific
literature. Several particularly common modifications,
glycosylation, lipid attachment, sulfation, gamma-carboxylation of
glutamic acid residues, hydroxylation and ADP-ribosylation, for
instance, are described in most basic texts, such as
Proteins--Structure and Molecular Properties, 2nd Ed., T. E.
Creighton, W. H. Freeman and Company, New York (1993). Many
detailed reviews are available on this subject, such as by Wold,
F., Posttranslational Covalent Modification of Proteins, B. C.
Johnson, Ed., Academic Press, New York 1-12 (1983); Seifter et al.
(Meth. Enzymol. 182: 626-646 (1990)) and Rattan et al. (Ann. N.Y.
Acad. Sci. 663:48-62 (1992)).
[0073] Accordingly, the drug-metabolizing enzyme peptides of the
present invention also encompass derivatives or analogs in which a
substituted amino acid residue is not one encoded by the genetic
code, in which a substituent group is included, in which the mature
drug-metabolizing enzyme peptide is fused with another compound,
such as a compound to increase the half-life of the
drug-metabolizing enzyme peptide (for example, polyethylene
glycol), or in which the additional amino acids are fused to the
mature drug-metabolizing enzyme peptide, such as a leader or
secretory sequence or a sequence for purification of the mature
drug-metabolizing enzyme peptide or a pro-protein sequence.
[0074] Protein/Peptide Uses
[0075] The proteins of the present invention can be used in
substantial and specific assays related to the functional
information provided in the Figures; to raise antibodies or to
elicit another immune response; as a reagent (including the labeled
reagent) in assays designed to quantitatively determine levels of
the protein (or its binding partner or ligand) in biological
fluids; and as markers for tissues in which the corresponding
protein is preferentially expressed (either constitutively or at a
particular stage of tissue differentiation or development or in a
disease state). Where the protein binds or potentially binds to
another protein or ligand (such as, for example, in a
drug-metabolizing enzyme-effector protein interaction or
drug-metabolizing enzyme-ligand interaction), the protein can be
used to identify the binding partner/ligand so as to develop a
system to identify inhibitors of the binding interaction. Any or
all of these uses are capable of being developed into reagent grade
or kit format for commercialization as commercial products.
[0076] Methods for performing the uses listed above are well known
to those skilled in the art. References disclosing such methods
include "Molecular Cloning: A Laboratory Manual", 2d ed., Cold
Spring Harbor Laboratory Press, Sambrook, J., E. F. Fritsch and T.
Maniatis eds., 1989, and "Methods in Enzymology: Guide to Molecular
Cloning Techniques", Academic Press, Berger, S. L. and A. R. Kimmel
eds., 1987.
[0077] Substantial chemical and structural homology exists between
the sulfotransferase protein described herein and heparan
sulfotransferase (3-OST) (see FIG. 1). As discussed in the
background, sulfotransferase are known in the art to be involved in
drug metabolism and heparan biosynthesis. Accordingly, the
sulfotransferase protein, and the encoding gene, provided by the
present invention is useful for treating, preventing, and/or
diagnosing disorders such as blood coagulation and disorders
associated with drug metabolism.
[0078] The potential uses of the peptides of the present invention
are based primarily on the source of the protein as well as the
class/action of the protein. For example, drug-metabolizing enzymes
isolated from humans and their human/mammalian orthologs serve as
targets for identifying agents for use in mammalian therapeutic
applications, e.g. a human drug, particularly in modulating a
biological or pathological response in a cell or tissue that
expresses the drug-metabolizing enzyme. Experimental data as
provided in FIG. 1 indicates that drug-metabolizing enzyme proteins
of the present invention are expressed in the lung. Specifically, a
virtual northern blot shows expression in carcinoid lung. In
addition, PCR-based tissue screening panel indicates expression in
human and human fetal brain, human bone marrow, human colon, human
fetal heart, human fetal liver, human fetal lung, human pancreas,
human placenta. A large percentage of pharmaceutical agents are
being developed that modulate the activity of drug-metabolizing
enzyme proteins, particularly members of the sulfotransferase
subfamily (see Background of the Invention). The structural and
functional information provided in the Background and Figures
provide specific and substantial uses for the molecules of the
present invention, particularly in combination with the expression
information provided in FIG. 1. Experimental data as provided in
FIG. 1 indicates expression in the lung. Such uses can readily be
determined using the information provided herein, that which is
known in the art, and routine experimentation.
[0079] The drug-metabolizing enzyme polypeptides (including
variants and fragments that may have been disclosed prior to the
present invention) are useful for biological assays related to
drug-metabolizing enzymes that are related to members of the
sulfotransferase subfamily. Such assays involve any of the known
drug-metabolizing enzyme functions or activities or properties
useful for diagnosis and treatment of drug-metabolizing
enzyme-related conditions that are specific for the subfamily of
drug-metabolizing enzymes that the one of the present invention
belongs to, particularly in cells and tissues that express the
drug-metabolizing enzyme. Experimental data as provided in FIG. 1
indicates that drug-metabolizing enzyme proteins of the present
invention are expressed in the lung. Specifically, a virtual
northern blot shows expression in carcinoid lung. In addition,
PCR-based tissue screening panel indicates expression in human and
human fetal brain, human bone marrow, human colon, human fetal
heart, human fetal liver, human fetal lung, human pancreas, human
placenta.
[0080] The drug-metabolizing enzyme polypeptides are also useful in
drug screening assays, in cell-based or cell-free systems.
Cell-based systems can be native, i.e., cells that normally express
the drug-metabolizing enzyme, as a biopsy or expanded in cell
culture. Experimental data as provided in FIG. 1 indicates
expression in the lung. In an alternate embodiment, cell-based
assays involve recombinant host cells expressing the
drug-metabolizing enzyme protein.
[0081] The polypeptides can be used to identify compounds that
modulate drug-metabolizing enzyme activity of the protein in its
natural state or an altered form that causes a specific disease or
pathology associated with the drug-metabolizing enzyme. Both the
drug-metabolizing enzymes of the present invention and appropriate
variants and fragments can be used in high-throughput screens to
assay candidate compounds for the ability to bind to the
drug-metabolizing enzyme. These compounds can be further screened
against a functional drug-metabolizing enzyme to determine the
effect of the compound on the drug-metabolizing enzyme activity.
Further, these compounds can be tested in animal or invertebrate
systems to determine activity/effectiveness. Compounds can be
identified that activate (agonist) or inactivate (antagonist) the
drug-metabolizing enzyme to a desired degree.
[0082] Further, the drug-metabolizing enzyme polypeptides can be
used to screen a compound for the ability to stimulate or inhibit
interaction between the drug-metabolizing enzyme protein and a
molecule that normally interacts with the drug-metabolizing enzyme
protein. Such assays typically include the steps of combining the
drug-metabolizing enzyme protein with a candidate compound under
conditions that allow the drug-metabolizing enzyme protein, or
fragment, to interact with the target molecule, and to detect the
formation of a complex between the protein and the target or to
detect the biochemical consequence of the interaction with the
drug-metabolizing enzyme protein and the target.
[0083] Candidate compounds include, for example, 1) peptides such
as soluble peptides, including Ig-tailed fusion peptides and
members of random peptide libraries (see, e.g., Lam et al., Nature
354:82-84 (1991); Houghten et al., Nature 354:84-86 (1991)) and
combinatorial chermistry-derived molecular libraries made of D-
and/or L-configuration amino acids; 2) phosphopeptides (e.g.,
members of random and partially degenerate, directed phosphopeptide
libraries, see, e.g.,. Songyang et al., Cell 72:767-778 (1993)); 3)
antibodies (e.g., polyclonal, monoclonal, humanized,
anti-idiotypic, chimeric, and single chain antibodies as well as
Fab, F(ab').sub.2, Fab expression library fragments, and
epitope-binding fragments of antibodies); and 4) small organic and
inorganic molecules (e.g., molecules obtained from combinatorial
and natural product libraries).
[0084] One candidate compound is a soluble fragment of the receptor
that competes for substrate binding. Other candidate compounds
include mutant drug-metabolizing enzymes or appropriate fragments
containing mutations that affect drug-metabolizing enzyme function
and thus compete for substrate. Accordingly, a fragment that
competes for substrate, for example with a higher affinity, or a
fragment that binds substrate but does not allow release, is
encompassed by the invention.
[0085] Any of the biological or biochemical functions mediated by
the drug-metabolizing enzyme can be used as an endpoint assay.
These include all of the biochemical or biochemical/biological
events described herein, in the references cited herein,
incorporated by reference for these endpoint assay targets, and
other functions known to those of ordinary skill in the art or that
can be readily identified using the information provided in the
Figures, particularly FIG. 2. Specifically, a biological function
of a cell or tissues that expresses the drug-metabolizing enzyme
can be assayed. Experimental data as provided in FIG. 1 indicates
that drug-metabolizing enzyme proteins of the present invention are
expressed in the lung. Specifically, a virtual northern blot shows
expression in carcinoid lung. In addition, PCR-based tissue
screening panel indicates expression in human and human fetal
brain, human bone marrow, human colon, human fetal heart, human
fetal liver, human fetal lung, human pancreas, human placenta.
[0086] Binding and/or activating compounds can also be screened by
using chimeric drug-metabolizing enzyme proteins in which the amino
terminal extracellular domain, or parts thereof, the entire
transmembrane domain or subregions, such as any of the seven
transmembrane segments or any of the intracellular or extracellular
loops and the carboxy terminal intracellular domain, or parts
thereof, can be replaced by heterologous domains or subregions. For
example, a substrate-binding region can be used that interacts with
a different substrate then that which is recognized by the native
drug-metabolizing enzyme. Accordingly, a different set of signal
transduction components is available as an end-point assay for
activation. This allows for assays to be performed in other than
the specific host cell from which the drug-metabolizing enzyme is
derived.
[0087] The drug-metabolizing enzyme polypeptides are also useful in
competition binding assays in methods designed to discover
compounds that interact with the drug-metabolizing enzyme (e.g.
binding partners and/or ligands). Thus, a compound is exposed to a
drug-metabolizing enzyme polypeptide under conditions that allow
the compound to bind or to otherwise interact with the polypeptide.
Soluble drug-metabolizing enzyme polypeptide is also added to the
mixture. If the test compound interacts with the soluble
drug-metabolizing enzyme polypeptide, it decreases the amount of
complex formed or activity from the drug-metabolizing enzyme
target. This type of assay is particularly useful in cases in which
compounds are sought that interact with specific regions of the
drug-metabolizing enzyme. Thus, the soluble polypeptide that
competes with the target drug-metabolizing enzyme region is
designed to contain peptide sequences corresponding to the region
of interest.
[0088] To perform cell free drug screening assays, it is sometimes
desirable to immobilize either the drug-metabolizing enzyme
protein, or fragment, or its target molecule to facilitate
separation of complexes from uncomplexed forms of one or both of
the proteins, as well as to accommodate automation of the
assay.
[0089] Techniques for immobilizing proteins on matrices can be used
in the drug screening assays. In one embodiment, a fusion protein
can be provided which adds a domain that allows the protein to be
bound-to a matrix. For example, glutathione-S-transferase fusion
proteins can be adsorbed onto glutathione sepharose beads (Sigma
Chemical, St. Louis, Mo.) or glutathione derivatized microtitre
plates, which are then combined with the cell lysates (e.g.,
.sup.35S-labeled) and the candidate compound, and the mixture
incubated under conditions conducive to complex formation (e.g., at
physiological conditions for salt and pH). Following incubation,
the beads are washed to remove any unbound label, and the matrix
immobilized and radiolabel determined directly, or in the
supernatant after the complexes are dissociated. Alternatively, the
complexes can be dissociated from the matrix, separated by
SDS-PAGE, and the level of drug-metabolizing enzyme-binding protein
found in the bead fraction quantitated from the gel using standard
electrophoretic techniques. For example, either the polypeptide or
its target molecule can be immobilized utilizing conjugation of
biotin and streptavidin using techniques well known in the art.
Alternatively, antibodies reactive with the protein but which do
not interfere with binding of the protein to its target molecule
can be derivatized to the wells of the plate, and the protein
trapped in the wells by antibody conjugation. Preparations of a
drug-metabolizing enzyme-binding protein and a candidate compound
are incubated in the drug-metabolizing enzyme protein-presenting
wells and the amount of complex trapped in the well can be
quantitated. Methods for detecting such complexes, in addition to
those described above for the GST-immobilized complexes, include
immunodetection of complexes using antibodies reactive with the
drug-metabolizing enzyme protein target molecule, or which are
reactive with drug-metabolizing enzyme protein and compete with the
target molecule, as well as enzyme-linked assays which rely on
detecting an enzymatic activity associated with the target
molecule.
[0090] Agents that modulate one of the drug-metabolizing enzymes of
the present invention can be identified using one or more of the
above assays, alone or in combination. It is generally preferable
to use a cell-based or cell free system first and then confirm
activity in an animal or other model system. Such model systems are
well known in the art and can readily be employed in this
context.
[0091] Modulators of drug-metabolizing enzyme protein activity
identified according to these drug screening assays can be used to
treat a subject with a disorder mediated by the drug-metabolizing
enzyme pathway, by treating cells or tissues that express the
drug-metabolizing enzyme. Experimental data as provided in FIG. 1
indicates expression in the lung. These methods of treatment
include the steps of administering a modulator of drug-metabolizing
enzyme activity in a pharmaceutical composition to a subject in
need of such treatment, the modulator being identified as described
herein.
[0092] In yet another aspect of the invention, the
drug-metabolizing enzyme proteins can be used as "bait proteins" in
a two-hybrid assay or three-hybrid assay (see, e.g., U.S. Pat. No.
5,283,317; Zervos et al. (1993) Cell 72:223-232; Madura et al.
(1993) J. Biol. Chem. 268:12046-12054; Bartel et al. (1993)
Biotechniques 14:920-924; Iwabuchi et al. (1993) Oncogene
8:1693-1696; and Brent WO94/10300), to identify other proteins,
which bind to or interact with the drug-metabolizing enzyme and are
involved in drug-metabolizing enzyme activity. Such
drug-metabolizing enzyme-binding proteins are likely to be
drug-metabolizing enzyme inhibitors.
[0093] The two-hybrid system is based on the modular nature of most
transcription factors, which consist of separable DNA-binding and
activation domains. Briefly, the assay utilizes two different DNA
constructs. In one construct, the gene that codes for a
drug-metabolizing enzyme protein is fused to a gene encoding the
DNA binding domain of a known transcription factor (e.g., GAL-4).
In the other construct, a DNA sequence, from a library of DNA
sequences, that encodes an unidentified protein ("prey" or
"sample") is fused to a gene that codes for the activation domain
of the known transcription factor. If the "bait" and the "prey"
proteins are able to interact, in vivo, forming a drug-metabolizing
enzyme-dependent complex, the DNA-binding and activation domains of
the transcription factor are brought into close proximity. This
proximity allows transcription of a reporter gene (e.g., LacZ)
which is operably linked to a transcriptional regulatory site
responsive to the transcription factor. Expression of the reporter
gene can be detected and cell colonies containing the functional
transcription factor can be isolated and used to obtain the cloned
gene which encodes the protein which interacts with the
drug-metabolizing enzyme protein.
[0094] This invention further pertains to novel agents identified
by the above-described screening assays. Accordingly, it is within
the scope of this invention to further use an agent identified as
described herein in an appropriate animal model. For example, an
agent identified as described herein (e.g., a drug-metabolizing
enzyme-modulating agent, an antisense drug-metabolizing enzyme
nucleic acid molecule, a drug-metabolizing enzyme-specific
antibody, or a drug-metabolizing enzyme-binding partner) can be
used in an animal or other model to determine the efficacy,
toxicity, or side effects of treatment with such an agent.
Alternatively, an agent identified as described herein can be used
in an animal or other model to determine the mechanism of action of
such an agent. Furthermore, this invention pertains to uses of
novel agents identified by the above-described screening assays for
treatments as described herein.
[0095] The drug-metabolizing enzyme proteins of the present
invention are also useful to provide a target for diagnosing a
disease or predisposition to disease mediated by the peptide.
Accordingly, the invention provides methods for detecting the
presence, or levels of, the protein (or encoding mRNA) in a cell,
tissue, or organism. Experimental data as provided in FIG. 1
indicates expression in the lung. The method involves contacting a
biological sample with a compound capable of interacting with the
drug-metabolizing enzyme protein such that the interaction can be
detected. Such an assay can be provided in a single detection
format or a multi-detection format such as an antibody chip
array.
[0096] One agent for detecting a protein in a sample is an antibody
capable of selectively binding to protein. A biological sample
includes tissues, cells and biological fluids isolated from a
subject, as well as tissues, cells and fluids present within a
subject.
[0097] The peptides of the present invention also provide targets
for diagnosing active protein activity, disease, or predisposition
to disease, in a patient having a variant peptide, particularly
activities and conditions that are known for other members of the
family of proteins to which the present one belongs. Thus, the
peptide can be isolated from a biological sample and assayed for
the presence of a genetic mutation that results in aberrant
peptide. This includes amino acid substitution, deletion,
insertion, rearrangement, (as the result of aberrant splicing
events), and inappropriate post-translational modification.
Analytic methods include altered electrophoretic mobility, altered
tryptic peptide digest, altered drug-metabolizing enzyme activity
in cell-based or cell-free assay, alteration in substrate or
antibody-binding pattern, altered isoelectric point, direct amino
acid sequencing, and any other of the known assay techniques useful
for detecting mutations in a protein. Such an assay can be provided
in a single detection format or a multi-detection format such as an
antibody chip array.
[0098] In vitro techniques for detection of peptide include enzyme
linked immunosorbent assays (ELISAs), Western blots,
immunoprecipitations and immunofluorescence using a detection
reagent, such as an antibody or protein binding agent.
Alternatively, the peptide can be detected in vivo in a subject by
introducing into the subject a labeled anti-peptide antibody or
other types of detection agent. For example, the antibody can be
labeled with a radioactive marker whose presence and location in a
subject can be detected by standard imaging techniques.
Particularly useful are methods that detect the allelic variant of
a peptide expressed in a subject and methods which detect fragments
of a peptide in a sample.
[0099] The peptides are also useful in pharmacogenomic analysis.
Pharmacogenomics deal with clinically significant hereditary
variations in the response to drugs due to altered drug disposition
and abnormal action in affected persons. See, e.g., Eichelbaum, M.
(Clin. Exp. Pharmacol. Physiol. 23(10-11):983-985 (1996)), and
Linder, M. W. (Clin. Chem. 43(2):254-266 (1997)). The clinical
outcomes of these variations result in severe toxicity of
therapeutic drugs in certain individuals or therapeutic failure of
drugs in certain individuals as a result of individual variation in
metabolism. Thus, the genotype of the individual can determine the
way a therapeutic compound acts on the body or the way the body
metabolizes the compound. Further, the activity of drug
metabolizing enzymes effects both the intensity and duration of
drug action. Thus, the pharmacogenomics of the individual permit
the selection of effective compounds and effective dosages of such
compounds for prophylactic or therapeutic treatment based on the
individual's genotype. The discovery of genetic polymorphisms in
some drug metabolizing enzymes has explained why some patients do
not obtain the expected drug effects, show an exaggerated drug
effect, or experience serious toxicity from standard drug dosages.
Polymorphisms can be expressed in the phenotype of the extensive
metabolizer and the phenotype of the poor metabolizer. Accordingly,
genetic polymorphism may lead to allelic protein variants of the
drug-metabolizing enzyme protein in which one or more of the
drug-metabolizing enzyme functions in one population is different
from those in another population. The peptides thus allow a target
to ascertain a genetic predisposition that can affect treatment
modality. Thus, in a ligand-based treatment, polymorphism may give
rise to amino terminal extracellular domains and/or other
substrate-binding regions that are more or less active in substrate
binding, and drug-metabolizing enzyme activation. Accordingly,
substrate dosage would necessarily be modified to maximize the
therapeutic effect within a given population containing a
polymorphism. As an alternative to genotyping, specific polymorphic
peptides could be identified.
[0100] The peptides are also useful for treating a disorder
characterized by an absence of, inappropriate, or unwanted
expression of the protein. Experimental data as provided in FIG. 1
indicates expression in the lung. Accordingly, methods for
treatment include the use of the drug-metabolizing enzyme protein
or fragments.
[0101] Antibodies
[0102] The invention also provides antibodies that selectively bind
to one of the peptides of the present invention, a protein
comprising such a peptide, as well as variants and fragments
thereof. As used herein, an antibody selectively binds a target
peptide when it binds the target peptide and does not significantly
bind to unrelated proteins. An antibody is still considered to
selectively bind a peptide even if it also binds to other proteins
that are not substantially homologous with the target peptide so
long as such proteins share homology with a fragment or domain of
the peptide target of the antibody. In this case, it would be
understood that antibody binding to the peptide is still selective
despite some degree of cross-reactivity.
[0103] As used herein, an antibody is defined in terms consistent
with that recognized within the art: they are multi-subunit
proteins produced by a mammalian organism in response to an antigen
challenge. The antibodies of the present invention include
polyclonal antibodies and monoclonal antibodies, as well as
fragments of such antibodies, including, but not limited to, Fab or
F(ab').sub.2, and Fv fragments.
[0104] Many methods are known for generating and/or identifying
antibodies to a given target peptide. Several such methods are
described by Harlow, Antibodies, Cold Spring Harbor Press,
(1989).
[0105] In general, to generate antibodies, an isolated peptide is
used as an immunogen and is administered to a mammalian organism,
such as a rat, rabbit or mouse. The full-length protein, an
antigenic peptide fragment or a fusion protein can be used.
Particularly important fragments are those covering functional
domains, such as the domains identified in FIG. 2, and domain of
sequence homology or divergence amongst the family, such as those
that can readily be identified using protein alignment methods and
as presented in the Figures.
[0106] Antibodies are preferably prepared from regions or discrete
fragments of the drug-metabolizing enzyme proteins. Antibodies can
be prepared from any region of the peptide as described herein.
However, preferred regions will include those involved in
function/activity and/or drug-metabolizing enzyme/binding partner
interaction. FIG. 2 can be used to identify particularly important
regions while sequence alignment can be used to identify conserved
and unique sequence fragments.
[0107] An antigenic fragment will typically comprise at least 8
contiguous amino acid residues. The antigenic peptide can comprise,
however, at least 10, 12, 14, 16 or more amino acid residues. Such
fragments can be selected on a physical property, such as fragments
correspond to regions that are located on the surface of the
protein, e.g., hydrophilic regions or can be selected based on
sequence uniqueness (see FIG. 2).
[0108] Detection on an antibody of the present invention can be
facilitated by coupling (i.e., physically linking) the antibody to
a detectable substance. Examples of detectable substances include
various enzymes, prosthetic groups, fluorescent materials,
luminescent materials, bioluminescent materials, and radioactive
materials. Examples of suitable enzymes include horseradish
peroxidase, alkaline phosphatase, .beta.-galactosidase, or
acetylcholinesterase; examples of suitable prosthetic group
complexes include streptavidin/biotin and avidin/biotin; examples
of suitable fluorescent materials include umbelliferone,
fluorescein, fluorescein isothiocyanate, rhodamine,
dichlorotriazinylamine fluorescein, dansyl chloride or
phycoerythrin; an example of a luminescent material includes
luminol; examples of bioluminescent materials include luciferase,
luciferin, and aequorin, and examples of suitable radioactive
material include .sup.125I, .sup.131I, .sup.35S or .sup.3H.
[0109] Antibody Uses
[0110] The antibodies can be used to isolate one of the proteins of
the present invention by standard techniques, such as affinity
chromatography or immunoprecipitation. The antibodies can
facilitate the purification of the natural protein from cells and
recombinantly produced protein expressed in host cells. In
addition, such antibodies are useful to detect the presence of one
of the proteins of the present invention in cells or tissues to
determine the pattern of expression of the protein among various
tissues in an organism and over the course of normal development.
Experimental data as provided in FIG. 1 indicates that
drug-metabolizing enzyme proteins of the present invention are
expressed in the lung. Specifically, a virtual northern blot shows
expression in carcinoid lung. In addition, PCR-based tissue
screening panel indicates expression in human and human fetal
brain, human bone marrow, human colon, human fetal heart, human
fetal liver, human fetal lung, human pancreas, human placenta.
Further, such antibodies can be used to detect protein in situ, in
vitro, or in a cell lysate or supernatant in order to evaluate the
abundance and pattern of expression. Also, such antibodies can be
used to assess abnormal tissue distribution or abnormal expression
during development or progression of a biological condition.
Antibody detection of circulating fragments of the full length
protein can be used to identify turnover.
[0111] Further, the antibodies can be used to assess expression in
disease states such as in active stages of the disease or in an
individual with a predisposition toward disease related to the
protein's function. When a disorder is caused by an inappropriate
tissue distribution, developmental expression, level of expression
of the protein, or expressed/processed form, the antibody can be
prepared against the normal protein. Experimental data as provided
in FIG. 1 indicates expression in the lung. If a disorder is
characterized by a specific mutation in the protein, antibodies
specific for this mutant protein can be used to assay for the
presence of the specific mutant protein.
[0112] The antibodies can also be used to assess normal and
aberrant subcellular localization of cells in the various tissues
in an organism. Experimental data as provided in FIG. 1 indicates
expression in the lung. The diagnostic uses can be applied, not
only in genetic testing, but also in monitoring a treatment
modality. Accordingly, where treatment is ultimately aimed at
correcting expression level or the presence of aberrant sequence
and aberrant tissue distribution or developmental expression,
antibodies directed against the protein or relevant fragments can
be used to monitor therapeutic efficacy.
[0113] Additionally, antibodies are useful in pharmacogenomic
analysis. Thus, antibodies prepared against polymorphic proteins
can be used to identify individuals that require modified treatment
modalities. The antibodies are also useful as diagnostic tools as
an immunological marker for aberrant protein analyzed by
electrophoretic mobility, isoelectric point, tryptic peptide
digest, and other physical assays known to those in the art.
[0114] The antibodies are also useful for tissue typing.
Experimental data as provided in FIG. 1 indicates expression in the
lung. Thus, where a specific protein has been correlated with
expression in a specific tissue, antibodies that are specific for
this protein can be used to identify a tissue type.
[0115] The antibodies are also useful for inhibiting protein
function, for example, blocking the binding of the
drug-metabolizing enzyme peptide to a binding partner such as a
substrate. These uses can also be applied in a therapeutic context
in which treatment involves inhibiting the protein's function. An
antibody can be used, for example, to block binding, thus
modulating (agonizing or antagonizing) the peptides activity.
Antibodies can be prepared against specific fragments containing
sites required for function or against intact protein that is
associated with a cell or cell membrane. See FIG. 2 for structural
information relating to the proteins of the present invention.
[0116] The invention also encompasses kits for using antibodies to
detect the presence of a protein in a biological sample. The kit
can comprise antibodies such as a labeled or labelable antibody and
a compound or agent for detecting protein in a biological sample;
means for determining the amount of protein in the sample; means
for comparing the amount of protein in the sample with a standard;
and instructions for use. Such a kit can be supplied to detect a
single protein or epitope or can be configured to detect one of a
multitude of epitopes, such as in an antibody detection array.
Arrays are described in detail below for nucleic acid arrays and
similar methods have been developed for antibody arrays.
[0117] Nucleic Acid Molecules
[0118] The present invention further provides isolated nucleic acid
molecules that encode a drug-metabolizing enzyme peptide or protein
of the present invention (cDNA, transcript and genomic sequence).
Such nucleic acid molecules will consist of, consist essentially
of, or comprise a nucleotide sequence that encodes one of the
drug-metabolizing enzyme peptides of the present invention, an
allelic variant thereof, or an ortholog or paralog thereof.
[0119] As used herein, an "isolated" nucleic acid molecule is one
that is separated from other nucleic acid present in the natural
source of the nucleic acid. Preferably, an "isolated" nucleic acid
is free of sequences that naturally flank the nucleic acid (i.e.,
sequences located at the 5' and 3' ends of the nucleic acid) in the
genornic DNA of the organism from which the nucleic acid is
derived. However, there can be some flanking nucleotide sequences,
for example up to about 5 KB, 4 KB, 3 KB, 2 KB, or 1 KB or less,
particularly contiguous peptide encoding sequences and peptide
encoding sequences within the same gene but separated by introns in
the genomic sequence. The important point is that the nucleic acid
is isolated from remote and unimportant flanking sequences such
that it can be subjected to the specific manipulations described
herein such as recombinant expression, preparation of probes and
primers, and other uses specific to the nucleic acid sequences.
[0120] Moreover, an "isolated" nucleic acid molecule, such as a
transcript/cDNA molecule, can be substantially free of other
cellular material, or culture medium when produced by recombinant
techniques, or chemical precursors or other chemicals when
chemically synthesized. However, the nucleic acid molecule can be
fused to other coding or regulatory sequences and still be
considered isolated.
[0121] For example, recombinant DNA molecules contained in a vector
are considered isolated. Further examples of isolated DNA molecules
include recombinant DNA molecules maintained in heterologous host
cells or purified (partially or substantially) DNA molecules in
solution. Isolated RNA-molecules include in vivo or in vitro RNA
transcripts of the isolated DNA molecules of the present invention.
Isolated nucleic acid molecules according to the present invention
further include such molecules produced synthetically.
[0122] Accordingly, the present invention provides nucleic acid
molecules that consist of the nucleotide sequence shown in FIG. 1
or 3 (SEQ ID NO:1, transcript sequence and SEQ ID NO:3, genomic
sequence), or any nucleic acid molecule that encodes the protein
provided in FIG. 2, SEQ ID NO:2. A nucleic acid molecule consists
of a nucleotide sequence when the nucleotide sequence is the
complete nucleotide sequence of the nucleic acid molecule.
[0123] The present invention further provides nucleic acid
molecules that consist essentially of the nucleotide sequence shown
in FIG. 1 or 3 (SEQ ID NO:1, transcript sequence and SEQ ID NO:3,
genomic sequence), or any nucleic acid molecule that encodes the
protein provided in FIG. 2, SEQ ID NO:2. A nucleic acid molecule
consists essentially of a nucleotide sequence when such a
nucleotide sequence is present with only a few additional nucleic
acid residues in the final nucleic acid molecule.
[0124] The present invention further provides nucleic acid
molecules that comprise the nucleotide sequences shown in FIG. 1 or
3 (SEQ ID NO:1, transcript sequence and SEQ ID NO:3, genomic
sequence), or any nucleic acid molecule that encodes the protein
provided in FIG. 2, SEQ ID NO:2. A nucleic acid molecule comprises
a nucleotide sequence when the nucleotide sequence is at least part
of the final nucleotide sequence of the nucleic acid molecule. In
such a fashion, the nucleic acid molecule can be only the
nucleotide sequence or have additional nucleic acid residues, such
as nucleic acid residues that are naturally associated with it or
heterologous nucleotide sequences. Such a nucleic acid molecule can
have a few additional nucleotides or can comprises several hundred
or more additional nucleotides. A brief description of how various
types of these nucleic acid molecules can be readily made/isolated
is provided below.
[0125] In FIGS. 1 and 3, both coding and non-coding sequences are
provided. Because of the source of the present invention, humans
genomic sequence (FIG. 3) and cDNA/transcript sequences (FIG. 1),
the nucleic acid molecules in the Figures will contain genomic
intronic sequences, 5' and 3' non-coding sequences, gene regulatory
regions and non-coding intergenic sequences. In general such
sequence features are either noted in FIGS. 1 and 3 or can readily
be identified using computational tools known in the art. As
discussed below, some of the non-coding regions, particularly gene
regulatory elements such as promoters, are useful for a variety of
purposes, e.g. control of heterologous gene expression, target for
-identifying gene activity modulating compounds, and are
particularly claimed as fragments of the genomic sequence provided
herein.
[0126] The isolated nucleic acid molecules can encode the mature
protein plus additional amino or carboxyl-terminal amino acids, or
amino acids interior to the mature peptide (when the mature form
has more than one peptide chain, for instance). Such sequences may
play a role in processing of a protein from precursor to a mature
form, facilitate protein trafficking, prolong or shorten protein
half-life or facilitate manipulation of a protein for assay or
production, among other things. As generally is the case in situ,
the additional amino acids may be processed away from the mature
protein by cellular enzymes.
[0127] As mentioned above, the isolated nucleic acid molecules
include, but are not limited to, the sequence encoding the
drug-metabolizing enzyme peptide alone, the sequence encoding the
mature peptide and additional coding sequences, such as a leader or
secretory sequence (e.g., a pre-pro or pro-protein sequence), the
sequence encoding the mature peptide, with or without the
additional coding sequences, plus additional non-coding sequences,
for example introns and non-coding 5' and 3' sequences such as
transcribed but non-translated sequences that play a role in
transcription, mRNA processing (including splicing and
polyadenylation signals), ribosome binding and stability of mRNA.
In addition, the nucleic acid molecule may be fused to a marker
sequence encoding, for example, a peptide that facilitates
purification.
[0128] Isolated nucleic acid molecules can be in the form of RNA,
such as mRNA, or in the form DNA, including cDNA and genomic DNA
obtained by cloning or produced by chemical synthetic techniques or
by a combination thereof. The nucleic acid, especially DNA, can be
double-stranded or single-stranded. Single-stranded nucleic acid
can be the coding strand (sense strand) or the non-coding strand
(anti-sense strand).
[0129] The invention further provides nucleic acid molecules that
encode fragments of the peptides of the present invention as well
as nucleic acid molecules that encode obvious variants of the
drug-metabolizing enzyme proteins of the present invention that are
described above. Such nucleic acid molecules may be naturally
occurring, such as allelic variants (same locus), paralogs
(different locus), and orthologs (different organism), or may be
constructed by recombinant DNA methods or by chemical synthesis.
Such non-naturally occurring variants may be made by mutagenesis
techniques, including those applied to nucleic acid molecules,
cells, or organisms. Accordingly, as discussed above, the variants
can contain nucleotide substitutions, deletions, inversions and
insertions. Variation can occur in either or both the coding and
non-coding regions. The variations can produce both conservative
and non-conservative amino acid substitutions.
[0130] The present invention further provides non-coding fragments
of the nucleic acid molecules provided in FIGS. 1 and 3. Preferred
non-coding fragments include, but are not limited to, promoter
sequences, enhancer sequences, gene modulating sequences and gene
termination sequences. Such fragments are useful in controlling
heterologous gene expression and in developing screens to identify
gene-modulating agents. A promoter can readily be identified as
being 5' to the ATG start site in the genomic sequence provided in
FIG. 3.
[0131] A fragment comprises a contiguous nucleotide sequence
greater than 12 or more nucleotides. Further, a fragment could at
least 30, 40, 50, 100, 250 or 500 nucleotides in length. The length
of the fragment will be based on its intended use. For example, the
fragment can encode epitope bearing regions of the peptide, or can
be useful as DNA probes and primers. Such fragments can be isolated
using the known nucleotide sequence to synthesize an
oligonucleotide probe. A labeled probe can then be used to screen a
cDNA library, genomic DNA library, or mRNA to isolate nucleic acid
corresponding to the coding region. Further, primers can be used in
PCR reactions to clone specific regions of gene.
[0132] A probe/primer typically comprises substantially a purified
oligonucleotide or oligonucleotide pair. The oligonucleotide
typically comprises a region of nucleotide sequence that hybridizes
under stringent conditions to at least about 12, 20, 25, 40, 50 or
more consecutive nucleotides.
[0133] Orthologs, homologs, and allelic variants can be identified
using methods well known in the art. As described in the Peptide
Section, these variants comprise a nucleotide sequence encoding a
peptide that is typically 60-70%, 70-80%, 80-90%, and more
typically at least about 90-95% or more homologous to the
nucleotide sequence shown in the Figure sheets or a fragment of
this sequence. Such nucleic acid molecules can readily be
identified as being able to hybridize under moderate to stringent
conditions, to the nucleotide sequence shown in the Figure sheets
or a fragment of the sequence. Allelic variants can readily be
determined by genetic locus of the encoding gene. As indicated by
the data presented in FIG. 3, the map position was determined to be
on chromosome 6 by ePCR.
[0134] FIG. 3 provides information on SNPs that have been
identified in a gene encoding the that drug-metabolizing enzyme
proteins of the present invention. 4 SNP variants were found, of
which all of them beyond ORFs.
[0135] As used herein, the term "hybridizes under stringent
conditions" is intended to describe conditions for hybridization
and washing under which nucleotide sequences encoding a peptide at
least 60-70% homologous to each other typically remain hybridized
to each other. The conditions can be such that sequences at least
about 60%, at least about 70%, or at least about 80% or more
homologous to each other typically remain hybridized to each other.
Such stringent conditions are known to those skilled in the art and
can be found in Current Protocols in Molecular Biology, John Wiley
& Sons, N.Y. (1989), 6.3.1-6.3.6. One example of stringent
hybridization conditions are hybridization in 6.times. sodium
chloride/sodium citrate (SSC) at about 45 C, followed by one or
more washes in 0.2.times.SSC, 0.1% SDS at 50-65 C. Examples of
moderate to low stringency hybridization conditions are well known
in the art.
[0136] Nucleic Acid Molecule Uses
[0137] The nucleic acid molecules of the present invention are
useful for probes, primers, chemical intermediates, and in
biological assays. The nucleic acid molecules are useful as a
hybridization probe for messenger RNA, transcript/cDNA and genomic
DNA to isolate full-length cDNA and georomic clones encoding the
peptide described in FIG. 2 and to isolate cDNA and genomic clones
that correspond to variants (alleles, orthologs, etc.) producing
the same or related peptides shown in FIG. 2. 4 SNPs have been
identified in the gene encoding the sulfotransferase protein
provided by the present invention and are given in FIG. 3.
[0138] The probe can correspond to any sequence along the entire
length of the nucleic acid molecules provided in the Figures.
Accordingly, it could be derived from 5' noncoding regions, the
coding region, and 3' noncoding regions. However, as discussed,
fragments are not to be construed as encompassing fragments
disclosed prior to the present invention.
[0139] The nucleic acid molecules are also useful as primers for
PCR to amplify any given region of a nucleic acid molecule and are
useful to synthesize antisense molecules of desired length and
sequence.
[0140] The nucleic acid molecules are also useful for constructing
recombinant vectors. Such vectors include expression vectors that
express a portion of, or all of, the peptide sequences. Vectors
also include insertion vectors, used to integrate into another
nucleic acid molecule sequence, such as into the cellular genome,
to alter in situ expression of a gene and/or gene product. For
example, an endogenous coding sequence can be replaced via
homologous recombination with all or part of the coding region
containing one or more specifically introduced mutations.
[0141] The nucleic acid molecules are also useful for expressing
antigenic portions of the proteins.
[0142] The nucleic acid molecules are also useful as probes for
determining the chromosomal positions of the nucleic acid molecules
by means of in situ hybridization methods. As indicated by the data
presented in FIG. 3, the map position was determined to be on
chromosome 6 by ePCR.
[0143] The nucleic acid molecules are also useful in making vectors
containing the gene regulatory regions of the nucleic acid
molecules of the present invention.
[0144] The nucleic acid molecules are also useful for designing
ribozymes corresponding to all, or a part, of the mRNA produced
from the nucleic acid molecules described herein.
[0145] The nucleic acid molecules are also useful for making
vectors that express part, or all, of the peptides.
[0146] The nucleic acid molecules are also useful for constructing
host cells expressing a part, or all, of the nucleic acid molecules
and peptides.
[0147] The nucleic acid molecules are also useful for constructing
transgenic animals expressing all, or a part, of the nucleic acid
molecules and peptides.
[0148] The nucleic acid molecules are also useful as hybridization
probes for determining the presence, level, form and distribution
of nucleic acid expression. Experimental data as provided in FIG. 1
indicates that drug-metabolizing enzyme proteins of the present
invention are expressed in the lung. Specifically, a virtual
northern blot shows expression in carcinoid lung. In addition,
PCR-based tissue screening panel indicates expression in human and
human fetal brain, human bone marrow, human colon, human fetal
heart, human fetal liver, human fetal lung, human pancreas, human
placenta. Accordingly, the probes can be used to detect the
presence of, or to determine levels of, a specific nucleic acid
molecule in cells, tissues, and in organisms. The nucleic acid
whose level is determined can be DNA or RNA. Accordingly, probes
corresponding to the peptides described herein can be used to
assess expression and/or gene copy number in a given cell, tissue,
or organism. These uses are relevant for diagnosis of disorders
involving an increase or decrease in drug-metabolizing enzyme
protein expression relative to normal results.
[0149] In vitro techniques for detection of mRNA include Northern
hybridizations and in situ hybridizations. In vitro techniques for
detecting DNA include Southern hybridizations and in situ
hybridization.
[0150] Probes can be used as a part of a diagnostic test kit for
identifying cells or tissues that express a drug-metabolizing
enzyme protein, such as by measuring a level of a drug-metabolizing
enzyme-encoding nucleic acid in a sample of cells from a subject
e.g., mRNA or genomic DNA, or determining if a drug-metabolizing
enzyme gene has been mutated. Experimental data as provided in FIG.
1 indicates that drug-metabolizing enzyme proteins of the present
invention are expressed in the lung. Specifically, a virtual
northern blot shows expression in carcinoid lung. In addition,
PCR-based tissue screening panel indicates expression in human and
human fetal brain, human bone marrow, human colon, human fetal
heart, human fetal liver, human fetal lung, human pancreas, human
placenta.
[0151] Nucleic acid expression assays are useful for drug screening
to identify compounds that modulate drug-metabolizing enzyme
nucleic acid expression.
[0152] The invention thus provides a method for identifying a
compound that can be used to treat a disorder associated with
nucleic acid expression of the drug-metabolizing enzyme gene,
particularly biological and pathological processes that are
mediated by the drug-metabolizing enzyme in cells and tissues that
express it. Experimental data as provided in FIG. 1 indicates
expression in the lung. The method typically includes assaying the
ability of the compound to modulate the expression of the
drug-metabolizing enzyme nucleic acid and thus identifying a
compound that can be used to treat a disorder characterized by
undesired drug-metabolizing enzyme nucleic acid expression. The
assays can be performed in cell-based and cell-free systems.
Cell-based assays include cells naturally expressing the
drug-metabolizing enzyme nucleic acid or recombinant cells
genetically engineered to express specific nucleic acid
sequences.
[0153] Thus, modulators of drug-metabolizing enzyme gene expression
can be identified in a method wherein a cell is contacted with a
candidate compound and the expression of mRNA determined. The level
of expression of drug-metabolizing enzyme mRNA in the presence of
the candidate compound is compared to the level of expression of
drug-metabolizing enzyme mRNA in the absence of the candidate
compound. The candidate compound can then be identified as a
modulator of nucleic acid expression based on this comparison and
be used, for example to treat a disorder characterized by aberrant
nucleic acid expression. When expression of mRNA is statistically
significantly greater in the presence of the candidate compound
than in its absence, the candidate compound is identified as a
stimulator of nucleic acid expression. When nucleic acid expression
is statistically significantly less in the presence of the
candidate compound than in its absence, the candidate compound is
identified as an inhibitor of nucleic acid expression.
[0154] The invention further provides methods of treatment, with
the nucleic acid as a target, using a compound identified through
drug screening as a gene modulator to modulate drug-metabolizing
enzyme nucleic acid expression in cells and tissues that express
the drug-metabolizing enzyme. Experimental data as provided in FIG.
1 indicates that drug-metabolizing enzyme proteins of the present
invention are expressed in the lung. Specifically, a virtual
northern blot shows expression in carcinoid lung. In addition,
PCR-based tissue screening panel indicates expression in human and
human fetal brain, human bone marrow, human colon, human fetal
heart, human fetal liver, human fetal lung, human pancreas, human
placenta. Modulation includes both up-regulation (i.e. activation
or agonization) or down-regulation (suppression or antagonization)
or nucleic acid expression.
[0155] Alternatively, a modulator for drug-metabolizing enzyme
nucleic acid expression can be a small molecule or drug identified
using the screening assays described herein as long as the drug or
small molecule inhibits the drug-metabolizing enzyme nucleic acid
expression in the cells and tissues that express the protein.
Experimental data as provided in FIG. 1 indicates expression in the
lung.
[0156] The nucleic acid molecules are also useful for monitoring
the effectiveness of modulating compounds on the expression or
activity of the drug-metabolizing enzyme gene in clinical trials or
in a treatment regimen. Thus, the gene expression pattern can serve
as a barometer for the continuing effectiveness of treatment with
the compound, particularly with compounds to which a patient can
develop resistance. The gene expression pattern can also serve as a
marker indicative of a physiological response of the affected cells
to the compound. Accordingly, such monitoring would allow either
increased administration of the compound or the administration of
alternative compounds to which the patient has not become
resistant. Similarly, if the level of nucleic acid expression falls
below a desirable level, administration of the compound could be
commensurately decreased.
[0157] The nucleic acid molecules are also useful in diagnostic
assays for qualitative changes in drug-metabolizing enzyme nucleic
acid expression, and particularly in qualitative changes that lead
to pathology. The nucleic acid molecules can be used to detect
mutations in drug-metabolizing enzyme genes and gene expression
products such as mRNA. The nucleic acid molecules can be used as
hybridization probes to detect naturally occurring genetic
mutations in the drug-metabolizing enzyme gene and thereby to
determine whether a subject with the mutation is at risk for a
disorder caused by the mutation. Mutations include deletion,
addition, or substitution of one or more nucleotides in the gene,
chromosomal rearrangement, such as inversion or transposition,
modification of genomic DNA, such as aberrant methylation patterns
or changes in gene copy number, such as amplification. Detection of
a mutated form of the drug-metabolizing enzyme gene associated with
a dysfunction provides a diagnostic tool for an active disease or
susceptibility to disease when the disease results from
overexpression, underexpression, or altered expression of a
drug-metabolizing enzyme protein.
[0158] Individuals carrying mutations in the drug-metabolizing
enzyme gene can be detected at the nucleic acid level by a variety
of techniques. FIG. 3 provides information on SNPs that have been
identified in a gene encoding the that drug-metabolizing enzyme
proteins of the present invention. 4 SNP variants were found, of
which all of them beyond ORFs. As indicated by the data presented
in FIG. 3, the map position was determined to be on chromosome 6 by
ePCR. Genomic DNA can be analyzed directly or can be amplified by
using PCR prior to analysis. RNA or cDNA can be used in the same
way. In some uses, detection of the mutation involves the use of a
probe/primer in a p6lymerase chain reaction (PCR) (see, e.g. U.S.
Pat. Nos. 4,683,195 and 4,683,202), such as anchor PCR or RACE PCR,
or, alternatively, in a ligation chain reaction (LCR) (see, e.g.,
Landegran et al., Science 241:1077-1080 (1988); and Nakazawa et
al., PNAS 91:360-364 (1994)), the latter of which can be
particularly useful for detecting point mutations in the gene (see
Abravaya et al., Nucleic Acids Res. 23:675-682 (1995)). This method
can include the steps of collecting a sample of cells from a
patient, isolating nucleic acid (e.g., genomic, mRNA or both) from
the cells of the sample, contacting the nucleic acid sample with
one or more primers which specifically hybridize to a gene under
conditions such that hybridization and amplification of the gene
(if present) occurs, and detecting the presence or absence of an
amplification product, or detecting the size of the amplification
product and comparing the length to a control sample. Deletions and
insertions can be detected by a change in size of the amplified
product compared to the normal genotype. Point mutations can be
identified by hybridizing amplified DNA to normal RNA or antisense
DNA sequences.
[0159] Alternatively, mutations in a drug-metabolizing enzyme gene
can be directly identified, for example, by alterations in
restriction enzyme digestion patterns determined by gel
electrophoresis.
[0160] Further, sequence-specific ribozymes (U.S. Pat. No.
5,498,531) can be used to score for the presence of specific
mutations by development or loss of a ribozyme cleavage site.
Perfectly matched sequences can be distinguished from mismatched
sequences by nuclease cleavage digestion assays or by differences
in melting temperature.
[0161] Sequence changes at specific locations can also be assessed
by nuclease protection assays such as RNase and S1 protection or
the chemical cleavage method. Furthermore, sequence differences
between a mutant drug-metabolizing enzyme gene and a wild-type gene
can be determined by direct DNA sequencing. A variety of automated
sequencing procedures can be utilized when performing the
diagnostic assays (Naeve, C. W., (1995) Biotechniques 19:448),
including sequencing by mass spectrometry (see, e.g., PCT
International Publication No. WO 94/16101; Cohen et al., Adv.
Chromatogr. 36:127-162 (1996); and Griffin et al., Appl. Biochem.
Biotechnol. 38:147-159 (1993)).
[0162] Other methods for detecting mutations in the gene include
methods in which protection from cleavage agents is used to detect
mismatched bases in RNA/RNA or RNA/DNA duplexes (Myers et al.,
Science 230:1242 (1985)); Cotton et al., PNAS 85:4397 (1988);
Saleeba et al., Meth. Enzymol. 217:286-295 (1992)), electrophoretic
mobility of mutant and wild type nucleic acid is compared (Orita et
al., PNAS 86:2766 (1989); Cotton et al., Mutat. Res. 285:125-144
(1993); and Hayashi et al., Genet. Anal. Tech. Appl. 9:73-79
(1992)), and movement of mutant or wild-type fragments in
polyacrylamide gels containing a gradient of denaturant is assayed
using denaturing gradient gel electrophoresis (Myers et al., Nature
313:495 (1985)). Examples of other techniques for detecting point
mutations include selective oligonucleotide hybridization,
selective amplification, and selective primer extension.
[0163] The nucleic acid molecules are also useful for testing an
individual for a genotype that while not necessarily causing the
disease, nevertheless affects the treatment modality. Thus, the
nucleic acid molecules can be used to study the relationship
between an individual's genotype and the individual's response to a
compound used for treatment (pharmacogenomic relationship).
Accordingly, the nucleic acid molecules described herein can be
used to assess the mutation content of the drug-metabolizing enzyme
gene in an individual in order to select an appropriate compound or
dosage regimen for treatment. FIG. 3 provides information on SNPs
that have been identified in a gene encoding the that
drug-metabolizing enzyme proteins of the present invention. 4 SNP
variants were found, of which all of them beyond ORFs.
[0164] Thus nucleic acid molecules displaying genetic variations
that affect treatment provide a diagnostic target that can be used
to tailor treatment in an individual. Accordingly, the production
of recombinant cells and animals containing these polymorphisms
allow effective clinical design of treatment compounds and dosage
regimens.
[0165] The nucleic acid molecules are thus useful as antisense
constructs to control drug-metabolizing enzyme gene expression in
cells, tissues, and organisms. A DNA antisense nucleic acid
molecule is designed to be complementary to a region of the gene
involved in transcription, preventing transcription and hence
production of drug-metabolizing enzyme protein. An antisense RNA or
DNA nucleic acid molecule would hybridize to the mRNA and thus
block translation of mRNA into drug-metabolizing enzyme
protein.
[0166] Alternatively, a class of antisense molecules can be used to
inactivate mRNA in order to decrease expression of
drug-metabolizing enzyme nucleic acid. Accordingly, these molecules
can treat a disorder characterized by abnormal or undesired
drug-metabolizing enzyme nucleic acid expression. This technique
involves cleavage by means of ribozymes containing nucleotide
sequences complementary to one or more regions in the mRNA that
attenuate the ability of the mRNA to be translated. Possible
regions include coding regions and particularly coding regions
corresponding to the catalytic and other functional activities of
the drug-metabolizing enzyme protein, such as substrate
binding.
[0167] The nucleic acid molecules also provide vectors for gene
therapy in patients containing cells that are aberrant in
drug-metabolizing enzyme gene expression. Thus, recombinant cells,
which include the patient's cells that have been engineered ex vivo
and returned to the patient, are introduced into an individual
where the cells produce the desired drug-metabolizing enzyme
protein to treat the individual.
[0168] The invention also encompasses kits for detecting the
presence of a drug-metabolizing enzyme nucleic acid in a biological
sample. Experimental data as provided in FIG. 1 indicates that
drug-metabolizing enzyme proteins of the present invention are
expressed in the lung. Specifically, a virtual northern blot shows
expression in carcinoid lung. In addition, PCR-based tissue
screening panel indicates expression in human and human fetal
brain, human bone marrow, human colon, human fetal heart, human
fetal liver, human fetal lung, human pancreas, human placenta. For
example, the kit can comprise reagents such as a labeled or
labelable nucleic acid or agent capable of detecting
drug-metabolizing enzyme nucleic acid in a biological sample; means
for determining the amount of drug-metabolizing enzyme nucleic acid
in the sample; and means for comparing the amount of
drug-metabolizing enzyme nucleic acid in the sample with a
standard. The compound or agent can be packaged in a suitable
container. The kit can further comprise instructions for using the
kit to detect drug-metabolizing enzyme protein mRNA or DNA.
[0169] Nucleic Acid Arrays
[0170] The present invention further provides nucleic acid
detection kits, such as arrays or microarrays of nucleic acid
molecules that are based on the sequence information provided in
FIGS. 1 and 3 (SEQ ID NOS:1 and 3).
[0171] As used herein "Arrays" or "Microarrays" refers to an array
of distinct polynucleotides or oligonucleotides synthesized on a
substrate, such as paper, nylon or other type of membrane, filter,
chip, glass slide, or any other suitable solid support. In one
embodiment, the microarray is prepared and used according to the
methods described in U.S. Pat. No. 5,837,832, Chee et al., PCT
application W095/11995 (Chee et al.), Lockhart, D. J. et al. (1996;
Nat. Biotech. 14: 1675-1680) and Schena, M. et al. (1996; Proc.
Natl. Acad. Sci. 93: 10614-10619), all of which are incorporated
herein in their entirety by reference. In other embodiments, such
arrays are produced by the methods described by Brown et al., U.S.
Pat. No. 5,807,522.
[0172] The microarray or detection kit is preferably composed of a
large number of unique, single-stranded nucleic acid sequences,
usually either synthetic antisense oligonucleotides or fragments of
cDNAs, fixed to a solid support. The oligonucleotides are
preferably about 6-60 nucleotides in length, more preferably 15-30
nucleotides in length, and most preferably about 20-25 nucleotides
in length. For a certain type of microarray or detection kit, it
may be preferable to use oligonucleotides that are only 7-20
nucleotides in length. The microarray or detection kit may contain
oligonucleotides that cover the known 5', or 3', sequence,
sequential oligonucleotides that cover the full length sequence; or
unique oligonucleotides selected from particular areas along the
length of the sequence. Polynucleotides used in the microarray or
detection kit may be oligonucleotides that are specific to a gene
or genes of interest.
[0173] In order to produce oligonucleotides to a known sequence for
a microarray or detection kit, the gene(s) of interest (or an ORF
identified from the contigs of the present invention) is typically
examined using a computer algorithm which starts at the 5' or at
the 3' end of the nucleotide sequence. Typical algorithms will then
identify oligomers of defined length that are unique to the gene,
have a GC content within a range suitable for hybridization, and
lack predicted secondary structure that may interfere with
hybridization. In certain situations it may be appropriate to use
pairs of oligonucleotides on a microarray or detection kit. The
"pairs" will be identical, except for one nucleotide that
preferably is located in the center of the sequence. The second
oligonucleotide in the pair (mismatched by one) serves as a
control. The number of oligonucleotide pairs may range from two to
one million. The oligomers are synthesized at designated areas on a
substrate using a light-directed chemical process. The substrate
may be paper, nylon or other type of membrane, filter, chip, glass
slide or any other suitable solid support.
[0174] In another aspect, an oligonucleotide may be synthesized on
the surface of the substrate by using a chemical coupling procedure
and an ink jet application apparatus, as described in PCT
application W095/251116 (Baldeschweiler et al.) which is
incorporated herein in its entirety by reference. In another
aspect, a "gridded" array analogous to a dot (or slot) blot may be
used to arrange and link cDNA fragments or oligonucleotides to the
surface of a substrate using a vacuum system, thermal, UV,
mechanical or chemical bonding procedures. An array, such as those
described above, may be produced by hand or by using available
devices (slot blot or dot, blot apparatus), materials (any suitable
solid support), and machines (including robotic instruments), and
may contain 8, 24, 96, 384, 1536, 6144 or more oligonucleotides, or
any other number between two and one million which lends itself to
the efficient use of commercially available instrumentation.
[0175] In order to conduct sample analysis using a microarray or
detection kit, the RNA or DNA from a biological sample is made into
hybridization probes. The mRNA is isolated, and cDNA is produced
and used as a template to make antisense RNA (aRNA). The aRNA is
amplified in the presence of fluorescent nucleotides, and labeled
probes are incubated with the microarray or detection kit so that
the probe sequences hybridize to complementary oligonucleotides of
the microarray or detection kit. Incubation conditions are adjusted
so that hybridization occurs with precise complementary matches or
with various degrees of less complementarity. After removal of
nonhybridized probes, a scanner is used to determine the levels and
patterns of fluorescence. The scanned images are examined to
determine degree of complementarity and the relative abundance of
each oligonucleotide sequence on the microarray or detection kit.
The biological samples may be obtained from any bodily fluids (such
as blood, urine, saliva, phlegm, gastric juices, etc.), cultured
cells, biopsies, or other tissue preparations. A detection system
may be used to measure the absence, presence, and amount of
hybridization for all of the distinct sequences simultaneously.
This data may be used for large-scale correlation studies on the
sequences, expression patterns, mutations, variants, or
polymorphisms among samples.
[0176] Using such arrays, the present invention provides methods to
identify the expression of the drug-metabolizing enzyme
proteins/peptides of the present invention. In detail, such methods
comprise incubating a test sample with one or more nucleic acid
molecules and assaying for binding of the nucleic acid molecule
with components within the test sample. Such assays will typically
involve arrays comprising many genes, at least one of which is a
gene of the present invention and or alleles of the
drug-metabolizing enzyme gene of the present invention. FIG. 3
provides information on SNPs that have been identified in a gene
encoding the that drug-metabolizing enzyme proteins of the present
invention. 4 SNP variants were found, of which all of them beyond
ORFs.
[0177] Conditions for incubating a nucleic acid molecule with a
test sample vary. Incubation Conditions depend on the format
employed in the assay, the detection methods employed, and the type
and nature of the nucleic acid molecule used in the assay. One
skilled in the art will recognize that any one of the commonly
available hybridization, amplification or array assay formats can
readily be adapted to employ the novel fragments of the Human
genome disclosed herein. Examples of such assays can be found in
Chard, T, An Introduction to Radioimmunoassay and Related
Techniques, Elsevier Science Publishers, Amsterdam, The Netherlands
(1986); Bullock, G. R. et al., Techniques in Immunocytochemistry,
Academic Press, Orlando, Fla. Vol. 1 (1 982), Vol. 2 (1983), Vol. 3
(1985); Tijssen, P., Practice and Theory of Enzyme Immunoassays:
Laboratory Techniques in Biochemistry and Molecular Biology,
Elsevier Science Publishers, Amsterdam, The Netherlands (1985).
[0178] The test samples of the present invention include cells,
protein or membrane extracts of cells. The test sample used in the
above-described method will vary based on the assay format, nature
of the detection method and the tissues, cells or extracts used as
the sample to be assayed. Methods for preparing nucleic acid
extracts or of cells are well known in the art and can be readily
be adapted in order to obtain a sample that is compatible with the
system utilized.
[0179] In another embodiment of the present invention, kits are
provided which contain the necessary reagents to carry out the
assays of the present invention.
[0180] Specifically, the invention provides a compartmentalized kit
to receive, in close confinement, one or more containers which
comprises: (a) a first container comprising one of the nucleic acid
molecules that can bind to a fragment of the Human genome disclosed
herein; and (b) one or more other containers comprising one or more
of the following: wash reagents, reagents capable of detecting
presence of a bound nucleic acid.
[0181] In detail, a compartmentalized kit includes any kit in which
reagents are contained in separate containers. Such containers
include small glass containers, plastic containers, strips of
plastic, glass or paper, or arraying material such as silica. Such
containers allows one to efficiently transfer reagents from one
compartment to another compartment such that the samples and
reagents are not cross-contaminated, and the agents or solutions of
each container can be added in a quantitative fashion from one
compartment to another. Such containers will include a container
which will accept the test sample, a container which contains the
nucleic acid probe, containers which contain wash reagents (such as
phosphate buffered saline, Tris-buffers, etc.), and containers
which contain the reagents used to detect the bound probe. One
skilled in the art will readily recognize that the previously
unidentified drug-metabolizing enzyme gene of the present invention
can be routinely identified using the sequence information
disclosed herein can be readily incorporated into one of the
established kit formats which are well known in the art,
particularly expression arrays.
[0182] Vectors/Host Cells
[0183] The invention also provides vectors containing the nucleic
acid molecules described herein. The term "vector" refers to a
vehicle, preferably a nucleic acid molecule, which can transport
the nucleic acid molecules. When the vector is a nucleic acid
molecule, the nucleic acid molecules are covalently linked to the
vector nucleic acid. With this aspect of the invention, the vector
includes a plasmid, single or double stranded phage, a single or
double stranded RNA or DNA viral vector, or artificial chromosome,
such as a BAC, PAC, YAC, OR MAC.
[0184] A vector can be maintained in the host cell as an
extrachromosomal element where it replicates and produces
additional copies of the nucleic acid molecules. Alternatively, the
vector may integrate into the host cell genome and produce
additional copies of the nucleic acid molecules when the host cell
replicates.
[0185] The invention provides vectors for the maintenance (cloning
vectors) or vectors for expression (expression vectors) of the
nucleic acid molecules. The vectors can function in prokaryotic or
eukaryotic cells or in both (shuttle vectors).
[0186] Expression vectors contain cis-acting regulatory regions
that are operably linked in the vector to the nucleic acid
molecules such that transcription of the nucleic acid molecules is
allowed in a host cell. The nucleic acid molecules can be
introduced into the host cell with a separate nucleic acid molecule
capable of affecting transcription. Thus, the second nucleic acid
molecule may provide a trans-acting factor interacting with the
cis-regulatory control region to allow transcription of the nucleic
acid molecules from the vector. Alternatively, a trans-acting
factor may be supplied by the host cell. Finally, a trans-acting
factor can be produced from the vector itself. It is understood,
however, that in some embodiments, transcription and/or translation
of the nucleic acid molecules can occur in a cell-free system.
[0187] The regulatory sequence to which the nucleic acid molecules
described herein can be operably linked include promoters for
directing mRNA transcription. These include, but are not limited
to, the left promoter from bacteriophage .lambda., the lac, TRIP,
and TAC promoters from E. coli, the early and late promoters from
SV40, the CMV immediate early promoter, the adenovirus early and
late promoters, and retrovirus long-terminal repeats.
[0188] In addition to control regions that promote transcription,
expression vectors may also include regions that modulate
transcription, such as repressor binding sites and enhancers.
Examples include the SV40 enhancer, the cytomegalovirus immediate
early enhancer, polyoma enhancer, adenovirus enhancers, and
retrovirus LTR enhancers.
[0189] In addition to containing sites for transcription initiation
and control, expression vectors can also contain sequences
necessary for transcription termination and, in the transcribed
region a ribosome binding site for translation. Other regulatory
control elements for expression include initiation and termination
codons as well as polyadenylation signals. The person of ordinary
skill in the art would be aware of the numerous regulatory
sequences that are useful in expression vectors. Such regulatory
sequences are described, for example, in Sambrook et al., Molecular
Cloning: A Laboratory Manual. 2nd. ed., Cold Spring Harbor
Laboratory Press, Cold Spring Harbor, N.Y., (1989).
[0190] A variety of expression vectors can be used to express a
nucleic acid molecule. Such vectors include chromosomal, episomal,
and virus-derived vectors, for example vectors derived from
bacterial plasmids, from bacteriophage, from yeast episomes, from
yeast chromosomal elements, including yeast artificial chromosomes,
from viruses such as baculoviruses, papovaviruses such as SV40,
Vaccinia viruses, adenoviruses, poxviruses, pseudorabies viruses,
and retroviruses. Vectors may also be derived from combinations of
these sources such as those derived from plasmid and bacteriophage
genetic elements, e.g. cosmids and phagemids. Appropriate cloning
and expression vectors for prokaryotic and eukaryotic hosts are
described in Sambrook et al., Molecular Cloning: A Laboratory
Manual. 2nd. ed., Cold Spring Harbor Laboratory Press, Cold Spring
Harbor, N.Y., (1989).
[0191] The regulatory sequence may provide constitutive expression
in one or more host cells (i.e. tissue specific) or may provide for
inducible expression in one or more cell types such as by
temperature, nutrient additive, or exogenous factor such as a
hormnone or other ligand. A variety of vectors providing for
constitutive and inducible expression in prokaryotic and eukaryotic
hosts are well known to those of ordinary skill in the art.
[0192] The nucleic acid molecules can be inserted into the vector
nucleic acid by well-known methodology. Generally, the DNA sequence
that will ultimately be expressed is joined to an expression vector
by cleaving the DNA sequence and the expression vector with one or
more restriction enzymes and then ligating the fragments together.
Procedures for restriction enzyme digestion and ligation are well
known to those of ordinary skill in the art.
[0193] The vector containing the appropriate nucleic acid molecule
can be introduced into an appropriate host cell for propagation or
expression using well-known techniques. Bacterial cells include,
but are not limited to, E. coli, Streptomyces, and Salmonella
typhimurium. Eukaryotic cells include, but are not limited to,
yeast, insect cells such as Drosophila, animal cells such as COS
and CHO cells, and plant cells.
[0194] As described herein, it may be desirable to express the
peptide as a fusion protein. Accordingly, the invention provides
fusion vectors that allow for the production of the peptides.
Fusion vectors can increase the expression of a recombinant
protein, increase the solubility of the recombinant protein, and
aid in the purification of the protein by acting for example as a
ligand for affinity purification. A proteolytic cleavage site may
be introduced at the junction of the fusion moiety so that the
desired peptide can ultimately be separated from the fusion moiety.
Proteolytic enzymes include, but are not limited to, factor Xa,
thrombin, and enterokinase. Typical fusion expression vectors
include pGEX (Smith et al., Gene 67:3140 (1988)), pMAL (New England
Biolabs, Beverly, Mass.) and pRIT5 (Pharmacia, Piscataway, N.J.)
which fuse glutathione S-transferase (GST), maltose E binding
protein, or protein A, respectively, to the target recombinant
protein. Examples of suitable inducible non-fusion E. coli
expression vectors include pTrc (Amann et al., Gene 69:301-315
(1988)) and pET 11d (Studier et al., Gene Expression Technology:
Methods in Enzymology 185:60-89 (1990)).
[0195] Recombinant protein expression can be maximized in host
bacteria by providing a genetic background wherein the host cell
has an impaired capacity to proteolytically cleave the recombinant
protein. (Gottesman, S., Gene Expression Technology: Methods in
Enzymology 185, Academic Press, San Diego, Calif. (1990) 119-128).
Alternatively, the sequence of the nucleic acid molecule of
interest can be altered to provide preferential codon usage for a
specific host cell, for example E. coli. (Wada et al., Nucleic
Acids Res. 20:2111-2118 (1992)).
[0196] The nucleic acid molecules can also be expressed by
expression vectors that are operative in yeast. Examples of vectors
for expression in yeast e.g., S. cerevisiae include pYepSec1
(Baldari, et al., EMBO J. 6:229-234 (1987)), pMFa (Kuijan et al.,
Cell 30:933-943(1982)), pJRY88 (Schultz et al., Gene 54:113-123
(1987)), and pYES2 (Invitrogen Corporation, San Diego, Calif.).
[0197] The nucleic acid molecules can also be expressed in insect
cells using, for example, baculovirus expression vectors.
Baculovirus vectors available for expression of proteins in
cultured insect cells (e.g., Sf 9 cells) include the pAc series
(Smith et al., Mol. Cell Biol. 3:2156-2165 (1983)) and the pVL
series (Lucklow et al., Virology 170:31-39 (1989)).
[0198] In certain embodiments of the invention, the nucleic acid
molecules described herein are expressed in mammalian cells using
mammalian expression vectors. Examples of mammalian expression
vectors include pCDM8 (Seed, B. Nature 329:840(1987)) and pMF2PC
(Kaufman et al., EMBO J. 6:187-195 (1987)).
[0199] The expression vectors listed herein are provided by way of
example only of the well-known vectors available to those of
ordinary skill in the art that would be useful to express the
nucleic acid molecules. The person of ordinary skill in the art
would be aware of other vectors suitable for maintenance
propagation or expression of the nucleic acid molecules described
herein. These are found for example in Sambrook, J., Fritsh, E. F.,
and Maniatis, T. Molecular Cloning: A Laboratory Manual. 2nd, ed.,
Cold Spring Harbor Laboratory, Cold Spring Harbor Laboratory Press,
Cold Spring Harbor, N.Y., 1989.
[0200] The invention also encompasses vectors in which the nucleic
acid sequences described herein are cloned into the vector in
reverse orientation, but operably linked to a regulatory sequence
that permits transcription of antisense RNA. Thus, an antisense
transcript can be produced to all, or to a portion, of the nucleic
acid molecule sequences described herein, including both coding and
non-coding regions. Expression of this antisense RNA is subject to
each of the parameters described above in relation to expression of
the sense RNA (regulatory sequences, constitutive or inducible
expression, tissue-specific expression).
[0201] The invention also relates to recombinant host cells
containing the vectors described herein. Host cells therefore
include prokaryotic cells, lower eukaryotic cells such as yeast,
other eukaryotic cells such as insect cells, and higher eukaryotic
cells such as mammalian cells.
[0202] The recombinant host cells are prepared by introducing the
vector constructs described herein into the cells by techniques
readily available to the person of ordinary skill in the art. These
include, but are not limited to, calcium phosphate transfection,
DEAE-dextran-mediated transfection, cationic lipid-mediated
transfection, electroporation, transduction, infection,
lipofection, and other techniques such as those found in Sambrook,
et al. (Molecular Cloning: A Laboratory Manual. 2nd, ed., Cold
Spring Harbor Laboratory, Cold Spring Harbor Laboratory Press, Cold
Spring Harbor, N.Y., 1989).
[0203] Host cells can contain more than one vector. Thus, different
nucleotide sequences can be introduced on different vectors of the
same cell. Similarly, the nucleic acid molecules can be introduced
either alone or with other nucleic acid molecules that are not
related to the nucleic acid molecules such as those providing
trans-acting factors for expression vectors. When more than one
vector is introduced into a cell, the vectors can be introduced
independently, co-introduced or joined to the nucleic acid molecule
vector.
[0204] In the case of bacteriophage and viral vectors, these can be
introduced into cells as packaged or encapsulated virus by standard
procedures for infection and transduction. Viral vectors can be
replication-competent or replication-defective. In the case in
which viral replication is defective, replication will occur in
host cells providing functions that complement the defects.
[0205] Vectors generally include selectable markers that enable the
selection of the subpopulation of cells that contain the
recombinant vector constructs. The marker can be contained in the
same vector that contains the nucleic acid molecules described
herein or may be on a separate vector. Markers include tetracycline
or ampicillin-resistance genes for prokaryotic host cells and
dihydrofolate reductase or neomycin resistance for eukaryotic host
cells. However, any marker that provides selection for a phenotypic
trait will be effective.
[0206] While the mature proteins can be produced in bacteria,
yeast, mammalian cells, and other cells under the control of the
appropriate regulatory sequences, cell-free transcription and
translation systems can also be used to produce these proteins
using RNA derived from the DNA constructs described herein.
[0207] Where secretion of the peptide is desired, appropriate
secretion signals are incorporated into the vector. The signal
sequence can be endogenous to the peptides or heterologous to these
peptides.
[0208] Where the peptide is not secreted into the medium, the
protein can be isolated from the host cell by standard disruption
procedures, including freeze thaw, sonication, mechanical
disruption, use of lysing agents and the like. The peptide can then
be recovered and purified by well-known purification methods
including ammonium sulfate precipitation, acid extraction, anion or
cationic exchange chromatography, phosphocellulose chromatography,
hydrophobic-interaction chromatography, affinity chromatography,
hydroxylapatite chromatography, lectin chromatography, or high
performance liquid chromatography.
[0209] It is also understood that depending upon the host cell in
recombinant production of the peptides described herein, the
peptides can have various glycosylation patterns, depending upon
the cell, or maybe non-glycosylated as when produced in bacteria.
In addition, the peptides may include an initial modified
methionine in some cases as a result of a host-mediated
process.
[0210] Uses of Vectors and Host Cells
[0211] The recombinant host cells expressing the peptides described
herein have a variety of uses. First, the cells are useful for
producing a drug-metabolizing enzyme protein or peptide that can be
further purified to produce desired amounts of drug-metabolizing
enzyme protein or fragments. Thus, host cells containing expression
vectors are useful for peptide production.
[0212] Host cells are also useful for conducting cell-based assays
involving the drug-metabolizing enzyme protein or drug-metabolizing
enzyme protein fragments, such as those described above as well as
other formats known in the art. Thus, a recombinant host cell
expressing a native drug-metabolizing enzyme protein is useful for
assaying compounds that stimulate or inhibit drug-metabolizing
enzyme protein function.
[0213] Host cells are also useful for identifying drug-metabolizing
enzyme protein mutants in which these functions are affected. If
the mutants naturally occur and give rise to a pathology, host
cells containing the mutations are useful to assay compounds that
have a desired effect on the mutant drug-metabolizing enzyme
protein (for example, stimulating or inhibiting function) which may
not be indicated by their effect on the native drug-metabolizing
enzyme protein.
[0214] Genetically engineered host cells can be further used to
produce non-human transgenic animals. A transgenic animal is
preferably a mammal, for example a rodent, such as a rat or mouse,
in which one or more of the cells of the animal include a
transgene. A transgene is exogenous DNA which is integrated into
the genome of a cell from which a transgenic animal develops and
which remains in the genome of the mature animal in one or more
cell types or tissues of the transgenic animal. These animals are
useful for studying the function of a drug-metabolizing enzyme
protein and identifying and evaluating modulators of
drug-metabolizing enzyme protein activity. Other examples of
transgenic animals include non-human primates, sheep, dogs, cows,
goats, chickens, and amphibians.
[0215] A transgenic animal can be produced by introducing nucleic
acid into the male pronuclei of a fertilized oocyte, e.g., by
microinjection, retroviral infection, and allowing the oocyte to
develop in a pseudopregnant female foster animal. Any of the
drug-metabolizing enzyme protein nucleotide sequences can be
introduced as a transgene into the genome of a non-human animal,
such as a mouse.
[0216] Any of the regulatory or other sequences useful in
expression vectors can form part of the transgenic sequence. This
includes intronic sequences and polyadenylation signals, if not
already included. A tissue-specific regulatory sequence(s) can be
operably linked to the transgene to direct expression of the
drug-metabolizing enzyme protein to particular cells.
[0217] Methods for generating transgenic animals via embryo
manipulation and microinjection, particularly animals such as mice,
have become conventional in the art and are described, for example,
in U.S. Pat. Nos. 4,736,866 and 4,870,009, both by Leder et al.,
U.S. Pat. No. 4,873,191 by Wagner et al. and in Hogan, B.,
Manipulating the Mouse Embryo, (Cold Spring Harbor Laboratory
Press, Cold Spring Harbor, N.Y., 1986). Similar methods are used
for production of other transgenic animals. A transgenic founder
animal can be identified based upon the presence of the transgene
in its genome and/or expression of transgenic mRNA in tissues or
cells of the animals. A transgenic founder animal can then be used
to breed additional animals carrying the transgene. Moreover,
transgenic animals carrying a transgene can further be bred to
other transgenic animals carrying other transgenes. A transgenic
animal also includes animals in which the entire animal or tissues
in the animal have been produced using the homologously recombinant
host cells described herein.
[0218] In another embodiment, transgenic non-human animals can be
produced which contain selected systems that allow for regulated
expression of the transgene. One example of such a system is the
cre/loxP recombinase system of bacteriophage P1. For a description
of the cre/loxP recombinase system, see, e.g., Lakso et al. PNAS
89:6232-6236 (1992). Another example of a recombinase system is the
FLP recombinase system of S. cerevisiae (O'Gorman et al. Science
251:1351-1355 (1991). If a cre/loxP recombinase system is used to
regulate expression of the transgene, animals containing transgenes
encoding both the Cre recombinase and a selected protein is
required. Such animals can be provided through the construction of
"double" transgenic animals, e.g., by mating two transgenic
animals, one containing a transgene encoding a selected protein and
the other containing a transgene encoding a recombinase.
[0219] Clones of the non-human transgenic animals described herein
can also be produced according to the methods described in Wilmut,
I. et al. Nature 385:810-813 (1997) and PCT International
Publication Nos. WO 97/07668 and WO 97/07669. In brief, a cell,
e.g., a somatic cell, from the transgenic animal can be isolated
and induced to exit the growth cycle and enter G.sub.o phase. The
quiescent cell can then be fused, e.g., through the use of
electrical pulses, to an enucleated oocyte from an animal of the
same species from which the quiescent cell is isolated. The
reconstructed oocyte is then cultured such that it develops to
morula or blastocyst and then transferred to pseudopregnant female
foster animal. The offspring born of this female foster animal will
be a clone of the animal from which the cell, e.g., the somatic
cell, is isolated.
[0220] Transgenic animals containing recombinant cells that express
the peptides described herein are useful to conduct the assays
described herein in an in vivo context. Accordingly, the various
physiological factors that are present in vivo and that could
effect substrate binding, drug-metabolizing enzyme protein
activation, and signal transduction, may not be evident from in
vitro cell-free or cell-based assays. Accordingly, it is useful to
provide non-human transgenic animals to assay in vivo
drug-metabolizing enzyme protein function, including substrate
interaction, the effect of specific mutant drug-metabolizing enzyme
proteins on drug-metabolizing enzyme protein function and substrate
interaction, and the effect of chimeric drug-metabolizing enzyme
proteins. It is also possible to assess the effect of null
mutations, that is mutations that substantially or completely
eliminate one or more drug-metabolizing enzyme protein
functions.
[0221] All publications and patents mentioned in the above
specification are herein incorporated by reference. Various
modifications and variations of the described method and system of
the invention will be apparent to those skilled in the art without
departing from the scope and spirit of the invention. Although the
invention has been described in connection with specific preferred
embodiments, it should be understood that the invention as claimed
should not be unduly limited to such specific embodiments. Indeed,
various modifications of the above-described modes for carrying out
the invention which are obvious to those skilled in the field of
molecular biology or related fields are intended to be within the
scope of the following claims.
Sequence CWU 1
1
4 1 970 DNA Homo sapiens 1 atgagcttaa agtgtctctg tcttgcttgc
aggctacaac ccatttgccc cattgaaggt 60 cgactgggtg gagcccgcac
tcaggctgaa ttcccacttc gcgccctgca gtttaagcgt 120 ggcctgctgc
acgagttccg gaagggcaac gcttccaagg agcaggttcg cctccatgac 180
ctggtccagc agctccccaa ggccattatc attggggtga ggaaaggagg cacaagggcc
240 ctgcttgaaa tgctgaacct acatccggca gtagtcaaag cctctcaaga
aatccacttt 300 tttgataatg atgagaatta tggtaagggc attgagtggt
ataggaaaaa gatgcctttt 360 tcctaccctc agcaaatcac aattgaaaag
agcccagcat attttatcac agaggaggtt 420 ccagaaagga tttacaaaat
gaactcatcc atcaagttgt tgatcattgt cagggagcca 480 accacaagag
ctatttctga ttatactcag gtgctagagg ggaaggagag gaagaacaaa 540
acttattaca agtttgagaa gctggccata gaccctaata catgcgaagt gaacacaaaa
600 tacaaagcag taagaaccag catctacacc aaacatctgg aaaggtggtt
gaaatacttt 660 ccaattgagc aatttcatgt cgtcgatgga gatcgcctca
tcacggaacc tctgccagaa 720 cttcagctcg tggagaagtt cctaaatctg
cctccaagga taagtcaata caatttatac 780 ttcaatgcta ccagagggtt
ttactgcttg cggtttaata ttatctttaa taagtgcctg 840 gcgggcagca
aggggcgcat tcatccagag gtggacccct ctgtcattac taaattgcgc 900
aaattctttc atccttttaa tcaaaaattt taccagatca ctgggaggac attgaactgg
960 ccctaagggc 970 2 321 PRT Homo sapiens 2 Met Ser Leu Lys Cys Leu
Cys Leu Ala Cys Arg Leu Gln Pro Ile Cys 1 5 10 15 Pro Ile Glu Gly
Arg Leu Gly Gly Ala Arg Thr Gln Ala Glu Phe Pro 20 25 30 Leu Arg
Ala Leu Gln Phe Lys Arg Gly Leu Leu His Glu Phe Arg Lys 35 40 45
Gly Asn Ala Ser Lys Glu Gln Val Arg Leu His Asp Leu Val Gln Gln 50
55 60 Leu Pro Lys Ala Ile Ile Ile Gly Val Arg Lys Gly Gly Thr Arg
Ala 65 70 75 80 Leu Leu Glu Met Leu Asn Leu His Pro Ala Val Val Lys
Ala Ser Gln 85 90 95 Glu Ile His Phe Phe Asp Asn Asp Glu Asn Tyr
Gly Lys Gly Ile Glu 100 105 110 Trp Tyr Arg Lys Lys Met Pro Phe Ser
Tyr Pro Gln Gln Ile Thr Ile 115 120 125 Glu Lys Ser Pro Ala Tyr Phe
Ile Thr Glu Glu Val Pro Glu Arg Ile 130 135 140 Tyr Lys Met Asn Ser
Ser Ile Lys Leu Leu Ile Ile Val Arg Glu Pro 145 150 155 160 Thr Thr
Arg Ala Ile Ser Asp Tyr Thr Gln Val Leu Glu Gly Lys Glu 165 170 175
Arg Lys Asn Lys Thr Tyr Tyr Lys Phe Glu Lys Leu Ala Ile Asp Pro 180
185 190 Asn Thr Cys Glu Val Asn Thr Lys Tyr Lys Ala Val Arg Thr Ser
Ile 195 200 205 Tyr Thr Lys His Leu Glu Arg Trp Leu Lys Tyr Phe Pro
Ile Glu Gln 210 215 220 Phe His Val Val Asp Gly Asp Arg Leu Ile Thr
Glu Pro Leu Pro Glu 225 230 235 240 Leu Gln Leu Val Glu Lys Phe Leu
Asn Leu Pro Pro Arg Ile Ser Gln 245 250 255 Tyr Asn Leu Tyr Phe Asn
Ala Thr Arg Gly Phe Tyr Cys Leu Arg Phe 260 265 270 Asn Ile Ile Phe
Asn Lys Cys Leu Ala Gly Ser Lys Gly Arg Ile His 275 280 285 Pro Glu
Val Asp Pro Ser Val Ile Thr Lys Leu Arg Lys Phe Phe His 290 295 300
Pro Phe Asn Gln Lys Phe Tyr Gln Ile Thr Gly Arg Thr Leu Asn Trp 305
310 315 320 Pro 3 5044 DNA Homo sapiens 3 attagcttcc aatcatttac
cttttactta gtaattgatc taatgatcac taatgcatta 60 ttatttagtt
gatgattctt ttcatttttt taactctgtc tctagtctct aaggggatag 120
cttttatttg gaattgaatt gtttggtggg ctttctaaaa gcctctcact tcagactttg
180 agattatgtc tgaaggtaac aggcttattt aggcccactc tccagtaact
gaagaccctg 240 ctttctggga gggagacaga ggttacttct accatccctt
ccaatcctaa acctgtatga 300 tttttcagtc tgggacccat actcagaatc
catgctttca gaagtgggaa agaatatgat 360 attttctcaa attttcacat
tctatcttga gttagggagt ccaaaaagcg actattctgc 420 aggatgtgat
ctcccagggt agaagataga aagaggaagg aagtaaagaa ggaaaatgac 480
cctttctaca agtggggaaa ttccatttga cctcaaacaa agcagagact gtctatatca
540 gccactctca gccagggtac tatgaaagaa ttaaatccta caaaaaagaa
tttgagtgac 600 tgtttcctca attcttccaa ggatggtact agcatcattc
taggtgctta ggacagaaat 660 ccatcaatgg atgccttatg gaattagagc
ttaattctca accagaaccc aagaagaact 720 gaaagatgaa cttgtattat
tccaatcagt gtcacaatta aaagcatctt tgcctatgta 780 tctattgata
attttacatc ctccatttaa agccctagta cattaatctc attaacaaat 840
ttataaaaac aaaattcatg tttctctaaa ctattaaccg ggttaaatcc tgttttttaa
900 aagctgtcta ggccaggcac agtagctcac gcctgtaatc ccagcacttt
gggaggctga 960 ggcaggcgaa tcacgagatc aggagttcaa gaccagccag
gccaacatgg tgaaaccttg 1020 tctctactaa aaatacaaaa attagctggg
tatggtggcg caggcctgta atcccagcta 1080 ctcgggaggc tgaggcagga
gaatctcttg aacccaggag acagagattg cagtgagcca 1140 agatcgtgcc
actgcactgc agcctaggca acagaccaag actccgtctc aaaaaaaaaa 1200
gaaaaaaaag ttgtctatat tttcacactt tccacaatga gcatgagttg ttttaaaaat
1260 cataaaaaag aaacatcgtg aaaagtagta tacattgata tttttcctta
agcattatga 1320 tagatagctg tttaaacaga acaaagacca agaccatgct
cctcaattct gcagaacagg 1380 ctgagtgtat tagtccgttt tcacagtgct
ataaagacat acctgagact gagtaattta 1440 taaagaaaaa aggtttaatt
gacacacagt tctgcatggc tggggaagcc tcagaaaact 1500 tacaatcatg
gcagaaggca aagaagaagc aaggcacgtc ttacttggtg gcaggagaga 1560
gagggagctt gcagggggcg gtgccacaca gttttaaacc atcaaatctc atgagaactc
1620 actatcatga aaacaagggg taaatacacc cccataatcc agtcacctcc
caccaagccc 1680 ctcctccgac atgtggggat tacaattcgg gatgagattt
gggtgggggc acagagccaa 1740 accatatcac tgggcatgac cttgaggttg
tttctcatct cagaaaacaa gaaagatgca 1800 atacagtctc ttgggaaaag
caagcaacag cctcattgcc acagaggggg agacacagat 1860 tccaaattat
tagaataact ggaagctttc aagtgtaaga attggtttaa cagccttttt 1920
gactgatatt atttaatttt accaagaagg ctaaaatgcc ctcacagatc aacttagggg
1980 aattataatg aacttcagtt caattcagac tatacctaaa aggaaactca
atttgctaac 2040 catatatgtt agccatgaca aattaaacag tcaccatcgt
ctactatcat tgtgactgtt 2100 accacatctt tctccctgag aaaagcagag
atggttgttc actattcagg ataatactga 2160 agtggaaatc ctcctgtctg
gctatatcca ttgcactcct tccttaatga gattgagttc 2220 ctgattttaa
tgggcttggc aatgagggct tgaggtttct ggccctgtca aggtcttgtt 2280
gatgcctggt cccaggtgtg gtaggtgata tacagcactt gctgatggca attgggtttg
2340 attctatatt cagcaaagtg gatatataat cctgacctct ttagatagaa
agagaaagag 2400 aggcagaaga aatatagtat tcttctggct atcctcaagg
cccagggcag agagtctcag 2460 aatgaaaatc tcagcaagtt ccaagattgg
aattttgcag gttgatgatg caaacagccc 2520 ggggcagaaa ctgggacctc
ctttcagatt atatctcaaa gattttcaag agccatctga 2580 gtgctgccga
gctgcaagaa aataatacca cacaaaatgt gaaacacatg gcctccctgc 2640
tacccttcca cctcccagct gaagattata atctcctgcc tttcactttt tcttaatgat
2700 tttaactggt gagctgttaa aaagctatta gtatggctgg tgccacttgt
ctatcctgta 2760 ctgcaaacag aagtgcacgc cgtagtcaat taagtgcttg
gagaataaaa aattttaagg 2820 agcactaata aaaaaattca tcaattatgt
gtgctccatt taatacatgg ttgcttaaaa 2880 taaaatttcc caaacatatg
ttcattatgg attgcagcag gctgggaacc agtggcttta 2940 tttatgcatt
taaagtcttg gtctgactgg ggaaccagaa aaatgaaaag ttagttgcaa 3000
tgagcttaaa gtgtctctgt cttgcttgca ggctacaacc catttgcccc attgaaggtc
3060 gactgggtgg agcccgcact caggctgaat tcccacttcg cgccctgcag
tttaagcgtg 3120 gcctgctgca cgagttccgg aagggcaacg cttccaagga
gcaggttcgc ctccatgacc 3180 tggtccagca gctccccaag gccattatca
ttggggtgag gaaaggaggc acaagggccc 3240 tgcttgaaat gctgaaccta
catccggcag tagtcaaagc ctctcaagaa atccactttt 3300 ttgataatga
tgagaattat ggtaagggca ttgagtggta taggaaaaag atgccttttt 3360
cctaccctca gcaaatcaca attgaaaaga gcccagcata ttttatcaca gaggaggttc
3420 cagaaaggat ttacaaaatg aactcatcca tcaagttgtt gatcattgtc
agggagccaa 3480 ccacaagagc tatttctgat tatactcagg tgctagaggg
gaaggagagg aagaacaaaa 3540 cttattacaa gtttgagaag ctggccatag
accctaatac atgcgaagtg aacacaaaat 3600 acaaagcagt aagaaccagc
atctacacca aacatctgga aaggtggttg aaatactttc 3660 caattgagca
atttcatgtc gtcgatggag atcgcctcat cacggaacct ctgccagaac 3720
ttcagctcgt ggagaagttc ctaaatctgc ctccaaggat aagtcaatac aatttatact
3780 tcaatgctac cagagggttt tactgcttgc ggtttaatat tatctttaat
aagtgcctgg 3840 cgggcagcaa ggggcgcatt catccagagg tggacccctc
tgtcattact aaattgcgca 3900 aattctttca tccttttaat caaaaatttt
accagatcac tgggaggaca ttgaactggc 3960 cctaaaataa tatgtcatac
aacactatgt gttgtgcctg gagacacaca atgtctcctg 4020 tagattaaaa
tatgcacttt tcctaggcag agctatccaa gtcatttttc catgtatatt 4080
tgtacatacg cagtgtgtga ccaaatataa gatcagttct ttttctactg aaaatttacg
4140 aaaaaaaaaa aattgctgtc tgcatagtcg catcttttaa gctatttaca
aaagagaaga 4200 ggtggtggta ttgggggaaa gtgacttcag ctattctcaa
agagttagtc ttcctttgat 4260 tcagaatttg tcacccgcca ttttcataga
tttaagccaa aagataaatg tgtgaaaatg 4320 taccaatggc tgcgaagctt
caggaagtag aggatccagt gatgcatttt ttttttccta 4380 agggaaagct
ggctctttaa ttcagatgct gaattggtgc catgaaaaca gaaaatgcta 4440
ttttcttatt atttaaaaga acgtcttatc tcataaaatt gacattgttc caaagttctt
4500 gtggtgattt tgcactattg ttttctcgta tggaccatgg tgtcacttgt
agcatgtcaa 4560 tcacacattg gaaagtcaag tccttttact tccatgttgt
atgtcaacag agagaaatgt 4620 catgtacata atgtatattg ttgtaaatac
tggtttcaca ctaagtaatt ctattttgta 4680 aactgaatat ggctatttaa
tttattgtga aaattaaatt tattgtggta tttaaaaatg 4740 gaatggatta
aaattactct atgtgcaatt tttttttttt ttactcattt tgttttacgt 4800
gccccctgct ggcttccaaa atggaagctg tttacgtgca tatgagagca cttggaaaga
4860 tgtgcttccc tgctggattt ctgtacccca gtgaaaatgt atttatgaag
tgaggttgag 4920 tatattaaaa aagaaaaacc tcaaccatct ggaaatcaag
tataatagcc acctcaaaga 4980 accctagtgc tgctctgcta caactttgta
acaattaatt tactcgcagt tgctgctgct 5040 cagg 5044 4 255 PRT Homo
sapiens 4 Gln Gln Leu Pro Gln Thr Ile Ile Ile Gly Val Arg Lys Gly
Gly Thr 1 5 10 15 Arg Ala Leu Leu Glu Met Leu Ser Leu His Pro Asp
Val Ala Ala Ala 20 25 30 Glu Asn Glu Val His Phe Phe Asp Trp Glu
Glu His Tyr Ser His Gly 35 40 45 Leu Gly Trp Tyr Leu Ser Gln Met
Pro Phe Ser Trp Pro His Gln Leu 50 55 60 Thr Val Glu Lys Thr Pro
Ala Tyr Phe Thr Ser Pro Lys Val Pro Glu 65 70 75 80 Arg Val Tyr Ser
Met Asn Pro Ser Ile Arg Leu Leu Leu Ile Leu Arg 85 90 95 Asp Pro
Ser Glu Arg Val Leu Ser Asp Tyr Thr Gln Val Phe Tyr Asn 100 105 110
His Met Gln Lys His Lys Pro Tyr Pro Ser Ile Glu Glu Phe Leu Val 115
120 125 Arg Asp Gly Arg Leu Asn Val Asp Tyr Lys Ala Leu Asn Arg Ser
Leu 130 135 140 Tyr His Val His Met Gln Asn Trp Leu Arg Phe Phe Pro
Leu Arg His 145 150 155 160 Ile His Ile Val Asp Gly Asp Arg Leu Ile
Arg Asp Pro Phe Pro Glu 165 170 175 Ile Gln Lys Val Glu Arg Phe Leu
Lys Leu Ser Pro Gln Ile Asn Ala 180 185 190 Ser Asn Phe Tyr Phe Asn
Lys Thr Lys Gly Phe Tyr Cys Leu Arg Asp 195 200 205 Ser Gly Arg Asp
Arg Cys Leu His Glu Ser Lys Gly Arg Ala His Pro 210 215 220 Gln Val
Asp Pro Lys Leu Leu Asn Lys Leu His Glu Tyr Phe His Glu 225 230 235
240 Pro Asn Lys Lys Phe Phe Glu Leu Val Gly Arg Thr Phe Asp Trp 245
250 255
* * * * *
References