U.S. patent application number 11/870229 was filed with the patent office on 2008-02-14 for dna encoding a plant lipase, transgenic plants and a method for controlling senescence in plants.
This patent application is currently assigned to Senesco Technologies, Inc.. Invention is credited to Yuwen Hong, Katalin Hudak, John E. Thompson, Tzann-Wei Wang.
Application Number | 20080039335 11/870229 |
Document ID | / |
Family ID | 22947104 |
Filed Date | 2008-02-14 |
United States Patent
Application |
20080039335 |
Kind Code |
A1 |
Thompson; John E. ; et
al. |
February 14, 2008 |
DNA ENCODING A PLANT LIPASE, TRANSGENIC PLANTS AND A METHOD FOR
CONTROLLING SENESCENCE IN PLANTS
Abstract
Regulation of expression of senescence in plants is achieved by
integration of a gene or gene fragment encoding senescence-induced
lipase into the plant genome in antisense orientation. The
carnation and Arabidopsis genes encoding senescence-induced lipase
are identified and the nucleotide sequences are used to modify
senescence in transgenic plants.
Inventors: |
Thompson; John E.;
(Waterloo, CA) ; Wang; Tzann-Wei; (Waterloo,
CA) ; Hudak; Katalin; (East Brunswick, NJ) ;
Hong; Yuwen; (Waterloo, CA) |
Correspondence
Address: |
WOMBLE CARLYLE SANDRIDGE & RICE, PLLC
ATTN: PATENT DOCKETING 32ND FLOOR
P.O. BOX 7037
ATLANTA
GA
30357-0037
US
|
Assignee: |
Senesco Technologies, Inc.
New Brunswick
NJ
|
Family ID: |
22947104 |
Appl. No.: |
11/870229 |
Filed: |
October 10, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11486250 |
Jul 14, 2006 |
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11870229 |
Oct 10, 2007 |
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10674540 |
Oct 1, 2003 |
7087419 |
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11486250 |
Jul 14, 2006 |
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09597774 |
Jun 19, 2000 |
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10674540 |
Oct 1, 2003 |
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09250280 |
Feb 16, 1999 |
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09597774 |
Jun 19, 2000 |
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09105812 |
Jun 26, 1998 |
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09250280 |
Feb 16, 1999 |
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Current U.S.
Class: |
506/2 |
Current CPC
Class: |
C12N 9/18 20130101; C12Q
1/6895 20130101; C40B 40/08 20130101; C12N 15/8249 20130101; C12N
15/8266 20130101; C12N 15/8273 20130101; C40B 30/04 20130101; C12Q
2600/158 20130101; C12N 9/20 20130101 |
Class at
Publication: |
506/002 |
International
Class: |
C40B 20/00 20060101
C40B020/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 14, 2000 |
US |
PCT/US00/03494 |
Claims
1.-53. (canceled)
54. A method for identifying a polynucleotide encoding a
senescence-induced plant lipase in a plant comprising: a) isolating
RNA from a senescing plant tissue; b) constructing a cDNA library
from the RNA obtained from the senescing plant tissue; c) screening
the cDNA library with a known senescence-induced lipase
polynucleotide; and, d) identifying a senescence-induced plant
lipase polynucleotide that has at least about 43% identity across
the entire coding region of the lipase with that of one of the
known senescence-induced lipase polynucleotides, and wherein the
polynucleotide comprises a polynucleotide encoding a conserved
plant lipase amino acid motif of GHSLG (SEQ ID NO:22) to identify a
polynucleotide encoding a senescence-induced lipase in the plant.
Description
[0001] This application is a continuation-in-part of application
Ser. No. 09/597,774, which is a continuation-in-part application of
application Ser. No. 09/250,280 which is a continuation-in-part
application of application Ser. No. 09/105,812, filed Jun. 26,
1998, and incorporated herein in its entirety by reference
thereto.
FIELD OF THE INVENTION
[0002] The present invention relates to polynucleotides which
encode plant polypeptides and which exhibit senescence-induced
expression, transgenic plants containing the polynucleotides in
antisense orientation and methods for controlling senescence in
plants. More particularly, the present invention relates to plant
lipase genes whose expression is induced by the onset of senescence
and the use of the lipase gene to control senescence in plants.
DESCRIPTION OF THE PRIOR ART
[0003] Senescence is the terminal phase of biological development
in the life of a plant. It presages death and occurs at various
levels of biological organization including the whole plant,
organs, flowers and fruit, tissues and individual cells.
[0004] Cell membrane deterioration is an early and fundamental
feature of senescence. Metabolism of lipids, in particular membrane
lipids, is one of several biochemical manifestations of cellular
senescence. Rose petals, for example, sustain an increase in acyl
hydrolase activity as senescence progresses that is accompanied by
a loss of membrane function (Borochov, et al., Plant Physiol.,
1982, 69, 296-299). Cell membrane deterioration is an early and
characteristic feature of senescence engendering increased
permeability, loss of ionic gradients and decreased function of key
membrane proteins such as ion pumps (Brown, et al., Plant Physiol.:
A Treatise, Vol. X. Academic Press, 1991, pp. 227-275). Much of
this decline in membrane structural and functional integrity can be
attributed to lipase-mediated phospholipid metabolism. Loss of
lipid phosphate has been demonstrated for senescing flower petals,
leaves, cotyledons and ripening fruit (Thompson, J. E., Senescence
and Aging in Plants, Academic Press, San Diego, 1988, pp. 51-83),
and this appears to give rise to major alterations in the molecular
organization of the membrane bilayer with advancing senescence that
lead to impairment of cell function. In particular, studies with a
number of senescing plant tissues have provided evidence for lipid
phase separations in membranes that appear to be attributable to an
accumulation of lipid metabolites in the membrane bilayer (McKersie
and Thompson, 1979, Biochim. Biophys. Acta, 508: 197-212; Chia, et
al., 1981, Plant Physiol., 67:415-420). There is growing evidence
that much of the metabolism of lipids in senescing tissue is
achieved through senescence-specific changes in gene expression
(Buchanan-Wollaston, V., J. Exp. Bot., 1997, 307:181-199).
[0005] The onset of senescence can be induced by different factors
both internal and external. For example, ethylene plays a role in
many plants in a variety of plant processes such as seed
germination, seedling development, fruit ripening and flower
senescence. Ethylene production in plants can also be associated
with trauma induced by mechanical wounding, chemicals, stress (such
as produced by temperature and water amount variations), and by
disease. Ethylene has been implicated in the regulation of leaf
senescence in many plants, but evidence obtained with transgenic
plants and ethylene response mutants has indicated that, although
ethylene has an effect on senescence, it is not an essential
regulator of the process. In many plants ethylene seems to have no
role in fruit ripening or senescence. For example in the ripening
of fruits of non-climacteric plants such as strawberry, in
senescence of some flowers such as day lilies and in leaf
senescence in some plants, such as Arabidopsis, and in particular,
in the monocots there is no requirement for ethylene signaling
(Smart, C. M., 1994, New Phytology, 126:419-448; Valpuesta, et al.,
1995, Plant Mol. Biol., 28:575-582).
[0006] External factors that induce premature initiation of
senescence include environmental stresses such as temperature,
drought, poor light or nutrient supply, as well as pathogen attack.
As in the case of natural (age-related) senescence, environmental
stress-induced senescence is characterized by a loss of cellular
membrane integrity. Specifically, exposure to environmental stress
induces electrolyte leakage reflecting membrane damage (Sharom, et
al., 1994, Plant Physiol., 105:305-308; Wright and Simon, 1973, J.
Exp. Botany, 24:400-411; Wright, M., 1974, Planta, 120:63-69; and
Eze et al., 1986, Physiologia Plantarum, 68:323-328), a decline in
membrane phospholipid levels (Wright, M., 1974, Planta, 120:63-69)
and lipid phase transitions (Sharom, et al., 1994, Plant Physiol.,
105:305-308), all of which can be attributed to the action of
lipase. Plant tissues exposed to environmental stress also produce
ethylene, commonly known as stress ethylene (Buchanan-Wollaston,
V., 1997, J. Exp. Botany, 48:181-199; Wright, M., 1974, Planta,
120:63-69). As noted above, ethylene is known to cause senescence
in some plants.
[0007] Membrane deterioration leading to leakage is also a seminal
feature of seed aging, and there is evidence that this too reflects
deesterification of fatty acids from membrane phospholipids
(McKersie, B. D., Senarata, T., Walker, M. A., Kendall, E. J. and
Hetherington, P. R. In: Senescence and Aging in Plants, Ed. L. D.
Nooden and A. C. Leoopold, academic Press, 1988. PP 441-464).
[0008] Presently, there is no widely applicable method for
controlling onset of senescence caused by either internal or
external, e.g., environmental stress, factors. At present, the
technology for controlling senescence and increasing the shelf-life
of fresh, perishable plant produce, such as fruits, flowers and
vegetables relies primarily upon reducing ethylene biosynthesis.
For example, U.S. Pat. No. 5,824,875 discloses transgenic geranium
plants which exhibit prolonged shelf-life due to reduction in
levels of ethylene resulting from the expression of one of three
1-amino-cyclopropane-1-carboxylate (ACC) synthase genes in
antisense orientation. Consequently, this technology is applicable
to only a limited range of plants that are ethylene-sensitive.
[0009] The shelf-life of some fruits is also extended by reducing
ethylene biosynthesis, which causes ripening to occur more slowly.
Since senescence of these fruits is induced after ripening, the
effect of reduced ethylene biosynthesis on shelf-life is indirect.
Another approach used to delay fruit ripening is by altering
cellular levels of polygalacturonase, a cell-wall softening enzyme
that is synthesized during the early stages of ripening. This
approach is similar to controlling ethylene biosynthesis in that
it, too, only indirectly affects senescence and again, is only
applicable to a narrow range of plants.
[0010] Thus, there is a need for a method of controlling senescence
in plants which is applicable to a wide variety of plants. It is
therefore of interest to develop senescence modulating technologies
that are applicable to all types of plants, regardless of ethylene
sensitivity.
SUMMARY OF THE INVENTION
[0011] This invention is based on the discovery and cloning of a
full length cDNA clone encoding a carnation senescence-induced
lipase and a full-length cDNA clone encoding Arabidopsis thaliana
senescence-induced lipase. The nucleotide sequences and
corresponding amino acid sequences for the senescence-induced
lipase genes are disclosed herein. The nucleotide sequence of the
carnation senescence-induced lipase gene has been successfully used
as a heterologous probe to detect corresponding genes or RNA
transcripts in several plants that are similarly regulated.
[0012] The invention provides a method for genetic modification of
plants to control the onset of senescence, either age-related
senescence or environmental stress-induced senescence. The
senescence-induced lipase nucleotide sequences of the invention,
fragments thereof, or combinations of such fragments, are
introduced into a plant cell in reverse orientation to inhibit
expression of the endogenous senescence-induced lipase gene,
thereby reducing the level of endogenous senescence-induced lipase
and altering senescence in the transformed plant.
[0013] Using the methods of the invention, transgenic plants are
generated and monitored for growth and development. Plants or
detached parts of plants (e.g., cuttings, flowers, vegetables,
fruits, seeds or leaves) exhibiting prolonged life or shelf life
with respect to plant growth, flowering, reduced fruit spoilage,
reduced seed aging and/or reduced yellowing of leaves due to
reduction in the level of senescence-induced lipase are selected as
desired products having improved properties including reduced leaf
yellowing, reduced petal abscission, reduced fruit spoilage during
shipping and storage. These superior plants are propagated.
Similarly, plants exhibiting increased resistance to environmental
stress, e.g., decreased susceptibility to low temperature
(chilling), drought, infection, etc., are selected as superior
products.
[0014] In one aspect, the present invention is directed to an
isolated DNA molecule encoding senescence-induced lipase, wherein
the DNA molecule hybridizes with SEQ ID NO:1, or a functional
derivative of the isolated DNA molecule which hybridizes with SEQ
ID NO:1. In one embodiment of the invention, the isolated DNA
molecule has the nucleotide sequence of SEQ ID NO:1, i.e., 100%
complementarity (sequence identity) to SEQ ID NO:1. In another
embodiment of this aspect of the invention, the isolated DNA
molecule contains the nucleotide sequence of SEQ ID NO:4.
[0015] The invention is also directed to an isolated DNA molecule
encoding senescence-induced lipase, wherein the DNA molecule
hybridizes with SEQ ID NO:18, or a functional derivative of the
isolated DNA molecule which hybridizes with SEQ ID NO:18. In one
embodiment of this aspect of the invention, the isolated DNA
molecule has the nucleotide sequence of SEQ ID NO:18, i.e., 100%
complementarity (sequence identity) to SEQ ID NO:18. In another
embodiment of this aspect of the invention, the isolated DNA
molecule contains the nucleotide sequence of SEQ ID NO:19.
[0016] In another embodiment of the invention, there is provided an
isolated protein encoded by a DNA molecule as described herein
above, or a functional derivative thereof. A preferred protein has
the amino acid sequence of SEQ ID NO:2, or is a functional
derivative thereof.
[0017] Also provided herein is an antisense oligonucleotide or
polynucleotide encoding an RNA molecule which is complementary to
at least a portion of an RNA transcript of the DNA molecule
described hereinabove, wherein the RNA molecule hybridizes with the
RNA transcript such that expression of endogenous
senescence-induced lipase is altered. The antisense oligonucleotide
or polynucleotide can be full length or preferably has about six to
about 100 nucleotides.
[0018] The antisense oligonucleotide or polynucleotide is
substantially complementary to a corresponding portion of one
strand of a DNA molecule encoding senescence-induced lipase,
wherein the DNA molecule encoding senescence-induced lipase
hybridizes with SEQ ID NO:1, SEQ ID NO:18 or both, or is
substantially complementary to a corresponding portion of an RNA
sequence encoded by the DNA molecule encoding senescence-induced
lipase. In one embodiment of the invention, the antisense
oligonucleotide or polynucleotide is substantially complementary to
a corresponding portion of one strand of the nucleotide sequence
SEQ ID NO:1, SEQ ID NO:18 or both or the RNA transcript encoded by
SEQ ID NO:1. In another embodiment, the antisense oligonucleotide
is substantially complementary to a corresponding portion of about
100 to about 200 nucleotides of the 5' non-coding portion or 3'-end
portion of one strand of a DNA molecule encoding senescence-induced
lipase, wherein the DNA molecule hybridizes with SEQ ID NO:1, SEQ
ID NO:18 or both. In another embodiment, the antisense oligo- or
polynucleotide is substantially complementary to a corresponding
portion of the open reading frame of one strand of the nucleotide
sequence SEQ ID NO:4 or the RNA transcript encoded by SEQ ID
NO:4.
[0019] The invention is further directed to a vector for
transformation of plant cells, comprising
[0020] (a) antisense nucleotide sequences substantially
complementary to (1) a corresponding portion of one strand of a DNA
molecule encoding senescence-induced lipase, wherein the DNA
molecule encoding senescence-induced lipase hybridizes with SEQ ID
NO:1, SEQ ID NO:18 or both or (2) a corresponding portion of an RNA
sequence encoded by the DNA molecule encoding senescence-induced
lipase; and
[0021] (b) regulatory sequences operatively linked to the antisense
nucleotide sequences such that the antisense nucleotide sequences
are expressed in a plant cell into which it is transformed.
[0022] The regulatory sequences include a promoter functional in
the transformed plant cell, which promoter may be inducible or
constitutive. Optionally, the regulatory sequences include a
polyadenylation signal.
[0023] The invention also provides a plant cell transformed with
the vector as described above, a plantlet or mature plant generated
from such a cell, or a plant part of such a plantlet or plant.
[0024] The present method is further directed to a method of
producing a plant having a reduced level of senescence-induced
lipase compared to an unmodified plant, comprising:
[0025] (1) transforming a plant with a vector as described
above;
[0026] (2) allowing the plant to grow to at least a plantlet
stage;
[0027] (3) assaying the transformed plant or plantlet for altered
senescence-induced lipase activity and/or altered senescence and/or
altered environmental stress-induced senescence and/or
ethylene-induced senescence; and
[0028] (4) selecting and growing a plant having altered
senescence-induced lipase activity and/or altered senescence and/or
altered environmental stressed-induced senescence or
ethylene-induced senescence compared to an nom-transformed
plant.
[0029] A plant produced as above, or progeny, hybrids, clones or
plant parts preferably exhibit reduced senescence-induced lipase
expression and delayed senescence and/or delayed stress-induced
senescence or ethylene-induced senescence.
[0030] This invention is further directed to a method of inhibiting
expression of endogenous senescence-induced lipase in a plant cell,
said method comprising:
[0031] (1) integrating into the genome of a plant a vector
comprising [0032] (A) antisense nucleotide sequences complementary
to (i) a corresponding portion of one strand of a DNA molecule
encoding endogenous senescence-induced lipase, wherein the DNA
molecule encoding the endogenous senescence-induced lipase
hybridizes with SEQ ID NO:1, SEQ ID NO:18 or both, or (ii) a
corresponding portion of an RNA sequence encoded by the endogenous
senescence-induced lipase gene; and [0033] (B) regulatory sequences
operatively linked to the antisense nucleotide sequences such that
the antisense nucleotide sequences are expressed; and
[0034] (2) growing said plant, whereby said antisense nucleotide
sequences are transcribed and the transcript binds to said
endogenous RNA whereby expression of said senescence-induced lipase
gene is inhibited.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 depicts the derived amino acid sequence (SEQ ID NO:2)
encoded by the senescence-induced lipase cDNA clone (SEQ ID NO:1)
obtained from a carnation flower cDNA library. Consensus motifs
within the amino acid sequence are as follows: single underline,
amidation site; dotted underline, protein kinase C phosphorylation
site; double underline, N-myristoylation site; box border, cAMP
phosphorylation site; shadow box, casein kinase II phosphorylation
site; cross-hatched box, consensus sequence of lipase family; and
dotted box, N-glycosylation site.
[0036] FIG. 2 depicts the derived full length carnation petal
senescence-induced lipase amino acid sequence (SEQ ID NO:2) in
alignment with partial sequences of lipase-like proteins. Carlip,
full length sequence of carnation petal senescence-induced lipase
(SEQ ID NO:11); arlip, partial sequence of lipase-like protein from
Arabidopsis thaliana (Gen Bank Accession No. AL021710) (SEQ ID
NO:12); ipolip, partial sequence of a lipase-like sequence from
Ipomea (Gen Bank Accession No. U55867) (SEQ ID NO:13); arlipi,
partial sequence of lipase-like protein from Arabidopsis thaliana
(Gen Bank Accession No. U93215) (SEQ ID NO:14). Identical amino
acids among three or four of the sequences are boxed.
[0037] FIG. 3 shows a Western blot analysis of the fusion protein
expression product obtained from carnation lipase cDNA expressed in
E. coli. The Western blot was probed with antibodies to the
senescence-induced lipase protein. Lane 1, maltose binding protein;
lane 2, fusion protein consisting of carnation lipase fused through
a proteolytic (Factor Xa) cleavage site to maltose binding protein
cDNA; lane 3, fusion protein partially cleaved with Factor Xa into
free lipase protein (50.2 kDa) and free maltose-binding
protein.
[0038] FIG. 4 is a Northern blot analysis of RNA isolated from
carnation flower petals at different stages of development. FIG. 4A
is the ethidium bromide stained gel of total RNA. Each lane
contained 10 .mu.g RNA. FIG. 4B is an autoradiograph of the
Northern blot probed with .sup.32P-dCTP-labelled full length
carnation senescence-induced lipase cDNA.
[0039] FIG. 5 is an in situ demonstration of lipolytic acyl
hydrolase, i.e., lipase activity of the protein product obtained by
over expression of the carnation senescence-induced lipase cDNA in
E. coli. mal, E. coli cells containing maltose binding protein
alone in a basal salt medium; mLip, E. coli cells containing the
fusion protein consisting of the carnation senescence-induced
lipase fused with maltose binding protein in basal salt medium; 40
mal/40 mLip, E. coli cells containing maltose binding protein alone
[mal] or the lipase-maltose binding protein fusion product [mbip]
in basal salt medium supplemented with Tween 40; 60 mal/60 mLip, E.
coli cells containing maltose binding protein alone [mal] or the
lipase-maltose binding protein fusion product [mLip] in basal salt
medium supplemented with Tween 60.
[0040] FIG. 6A illustrates a restriction enzyme map of the open
reading frame of the carnation senescence-induced lipase. The
numbers refer to nucleotides in the open reading frame.
[0041] FIG. 6B is a Southern blot analysis of carnation genomic DNA
digested with various restriction enzymes and probed with carnation
senescence-induced lipase cDNA.
[0042] FIG. 7 is the nucleotide sequence of the carnation
senescence-induced lipase cDNA clone (SEQ ID NO:1). Solid
underlining, non-coding sequence of the senescence-induced lipase
cDNA; non-underlined sequenced is the open reading frame.
[0043] FIG. 8 is the amino acid sequence of the carnation
senescence-induced lipase cDNA (SEQ ID NO:2).
[0044] FIG. 9A is a Northern blot analysis showing the expression
of the carnation lipase in stage II petals that have been exposed
to 0.5 ppm ethylene for 15 hours. FIG. 9A is an ethidium bromide
stained gel showing that each of the lanes was loaded with a
constant amount of carnation RNA (petals: lanes 1 and 2; leaves:
lanes 3 and 4; +, ethylene treated; -, untreated). FIG. 9B is an
autoradiogram of a Northern blot of the gel in FIG. 9A probed with
labelled full length carnation petal senescence-induced lipase
cDNA.
[0045] FIG. 10 is a partial nucleotide sequence of tomato leaf
genomic senescence-induced lipase (SEQ ID NO:6) and the
corresponding deduced amino acid sequence (SEQ ID NO:17). The
conserved lipase consensus motif is shaded; the sequences of the
primers used to generate the genomic fragment are each
underlined.
[0046] FIG. 11 is a bar graph showing the effects of chilling on
membrane leakiness. Tomato plants were chilled at 8.degree. for 48
hours and then rewarmed to room temperature. Diffusate leakage
(.mu.Mhos) from leaf disks was measured for control plants, which
had not been chilled, and for chilled plants for 6 and 24 hour
periods.
[0047] FIG. 12 is a Northern blot analysis of tomato leaf RNA
isolated from plants that had been chilled at 8.degree. C. for 48
hours and rewarmed to ambient temperature for 24 hours. FIG. 12A is
the ethidium bromide stained gel of total leaf RNA. FIG. 12B is an
autoradiograph of the Northern blot probed with .sup.32P
dCTP-labelled full length carnation senescence-induced lipase
cDNA.
[0048] FIG. 13 is a partial nucleotide sequence (SEQ ID NO:15) and
corresponding deduced amino acid sequence of an Arabidopsis EST
(GenBank Acc#: N38227) (SEQ ID NO:16) that is 55.5% identical over
a 64 amino acid region with the carnation senescence-induced
lipase. The conserved lipase consensus motif is shaded.
[0049] FIG. 14 is the nucleotide (top) (SEQ ID No:18) and derived
amino acid sequence (bottom) (SEQ ID NO:19) of the full-length
Arabidopsis senescence-induced lipase gene.
[0050] FIG. 15 is a Northern blot of total RNA isolated from leaves
of Arabidopsis plants at various stages (lane 1, two week-old
plants; lane 2, three week-old plants; lane 3, four week-old
plants; lane 4, five week-old plants; lane 5, six week-old plants)
probed with .sup.32P-dCTP-labelled full-length Arabidopsis
senescence-induced lipase. The autoradiograph is at the top (15A)
and the ethidium bromide stained gel below (15B).
[0051] FIG. 16 is a Northern blot of total RNA isolated from leaves
of three week-old Arabidopsis plants treated with 50 .mu.M ethephon
(a source of ethylene) and probed with .sup.32P-dCTP-labelled
full-length Arabidopsis senescence-induced lipase. The
autoradiograph is at the top (16A) and the ethidium bromide stained
gel below (16B).
[0052] FIG. 17 is a photograph of 4.6 week-old Arabidopsis
wild-type plants (left) and transgenic plants (right) expressing
the full-length Arabidopsis senescence-induced lipase gene in
antisense orientation showing increased leaf size in the transgenic
plants.
[0053] FIG. 18 is a photograph of 6.3 week-old Arabidopsis
wild-type plants (left) and transgenic plants (right) expressing
the full-length Arabidopsis senescence-induced lipase gene in
antisense orientation showing increased leaf size and delayed leaf
senescence in the transgenic plants.
[0054] FIG. 19 is a photograph of 7 week-old Arabidopsis wild-type
plants (left) and transgenic plants (right) expressing the
full-length Arabidopsis senescence-induced lipase gene in antisense
orientation showing increased leaf size in the transgenic
plants.
[0055] FIG. 20 is a graph showing the increase in seed yield in
three T.sub.1 transgenic Arabidopsis plant lines expressing the
senescence-induced lipase gene in antisense orientation. Seed yield
is expressed as volume of seed. SE for n=30 is shown for wild-type
plants.
[0056] FIG. 21 is a Western blot of total protein isolated from
leaves of four week-old Arabidopsis wild-type plants and
corresponding transgenic plants expressing the full-length
senescence-induced lipase gene in antisense orientation. (Lanes 1
and 2 were loaded with 9 .mu.g of protein, and lanes 3 and 4 were
loaded with 18 .mu.g of protein). The blot was probed with antibody
raised against the Arabidopsis senescence-induced lipase protein.
The expression of the senescence-induced lipase is reduced in all
transgenic plants.
DETAILED DESCRIPTION OF THE INVENTION
[0057] Methods and compositions are provided for altering the
expression of senescence-induced lipase gene (s) in plant cells.
Alteration of expression of the senescence-induced lipase gene(s)
in plants results in delayed onset of senescence and improved
resistance to environmental stress, thus extending the plant
shelf-life and/or growth period.
[0058] A full length cDNA sequence encoding a carnation lipase gene
exhibiting senescence-induced expression has been isolated from a
cDNA library made from RNA of senescing petals of carnation
(Dianthus caryophyllus) flowers. Polynucleotide probes
corresponding to selected regions of the isolated carnation flower
lipase cDNA sequence as well as the full length carnation lipase
cDNA were used to determine the presence of mRNA encoding the
lipase gene in senescing carnation leaves, ripening tomato fruit
and senescing green bean leaves, as well as environmentally
stressed (chilled) tomato leaves. Primers designed from the
carnation lipase cDNA were used to generate a polymerase chain
reaction (PCR) product using tomato leaf genomic DNA as template.
The PCR product contains a partial open reading frame which encodes
a partial protein sequence including the conserved lipase consensus
motif, ITFTGHSLGA (SEQ ID NO:3). The tomato nucleotide sequence has
53.4% sequence identity with the carnation senescence-induced
lipase sequence and 43.5% identity with Arabidopsis lipase
sequence. The Arabidopsis lipase sequence has 44.3% identity with
the carnation nucleotide sequence.
[0059] The carnation senescence-induced lipase gene of the present
invention was isolated by screening a cDNA expression library
prepared from senescing carnation petals with antibodies raised
against cytosolic lipid-protein particles, a source of the
carnation lipase. A positive full-length cDNA clone corresponding
to the carnation senescence-induced lipase gene was obtained and
sequenced. The nucleotide sequence of the senescence-induced lipase
cDNA clone is shown in SEQ ID NO:1. The cDNA clone encodes a 447
amino acid polypeptide (SEQ ID NO: 2) having a calculated molecular
mass of 50.2 kDa. Expression of the cDNA clone in E. coli yielded a
protein of the expected molecular weight that exhibits acyl
hydrolase activity, i.e., the expressed protein hydrolyzes
p-nitrophenylpalmitate, phospholipid and triacylglycerol. Based on
the expression pattern of the enzyme in developing carnation
flowers and the activity of the protein, it is involved in
senescence.
[0060] An Arabidopsis senescence-induced lipase gene of the present
invention was also isolated by PCR using a senescing Arabidopsis
leaf cDNA library as template in the reaction. The nucleotide and
derived amino acid sequence of the Arabidopsis senescence-induced
lipase gene is shown in FIG. 14 (SEQ ID NO:18) Based on the
expression pattern of the lipase gene in developing plants, it is
involved in senescence.
[0061] Northern blots of carnation petal total RNA probed with the
full length carnation cDNA show that the expression of the
senescence-induced lipase gene is significantly induced just prior
to the onset of natural senescence (FIG. 4). Northern blot analyses
also demonstrate that the senescence-induced lipase gene is induced
by environmental stress conditions, e.g., chilling (FIG. 12) and
ethylene (FIGS. 4 and 9), which is known to be produced in response
to environmental stress. The Northern blot analyses show that the
presence of carnation senescence-induced lipase mRNA is
significantly higher in senescing (developmental stage IV) than in
young stage I, II and III carnation petals. Furthermore,
ethylene-stimulated stage II flowers also show higher
senescence-induced lipase gene expression. Similarly, plants that
have been exposed to chilling temperatures and returned to ambient
temperature also show induced expression of the senescence-induced
lipase gene coincident with the development of chilling injury
symptoms (e.g., leakiness) (FIGS. 11 and 12).
[0062] Expression of the Arabidopsis senescence-induced lipase gene
is similarly regulated. Northern blot analysis of total RNA from
leaves of Arabidopsis plants at various stages of development show
that the lipase gene is upregulated coincident with the onset of
leaf senescence. (FIG. 15) Also, like the carnation
senescence-induced lipase gene, the Arabidopsis senescence-induced
lipase gene is upregulated by treatment with ethylene, a plant
hormone that induces leaf senescence. (FIG. 16)
[0063] The overall pattern of gene expression in various plants,
e.g., carnation, green beans, tomato, Arabidopsis, and various
plant tissues, e.g., leaves, fruit and flowers, demonstrates that
the lipase genes of the invention are involved in the initiation of
senescence in these plants and plant tissues. Thus, it is expected
that by substantially repressing or altering the expression of the
senescence-induced lipase genes in plant tissues, senescence,
deterioration and spoilage can be delayed, increasing the
shelf-life of perishable fruits, flowers and vegetables. This can
be achieved by producing transgenic plants in which the lipase cDNA
or an oligonucleotide fragment thereof is expressed in the
antisense configuration in fruits, flowers, vegetable, agronomic
crop plants and forest species, preferably using a constitutive
promoter such as the CaMV 35 S promoter, or using a tissue-specific
or senescence-inducible promoter.
[0064] The carnation senescence-induced lipase gene is a single
copy gene. Southern blot analysis of carnation genomic DNA cut with
various restriction enzymes that do not recognize sequences within
the open reading frame of the senescence-induced lipase cDNA was
carried out. The restriction enzyme-digested genomic DNA was probed
with .sup.32P-dCTP-labelled full length cDNA (SEQ ID NO:1). Under
high stringency hybridization conditions, only one restriction
fragment hybridizes to the cDNA clone (68.degree. C. for both
hybridization and washing; washing buffer: 0.2%.times.SSC, 0.1%
SDS). Thus, the carnation senescence-induced lipase gene is a
single copy gene (FIG. 6). The fact that this gene is not a member
of a multigene family in carnations strongly suggests that it is a
single copy gene in other plants.
[0065] Knowledge of the complete nucleotide sequence of the
carnation senescence-induced lipase gene or Arabidopsis
senescence-induced lipase gene is sufficient for the isolation of
the senescence-induced lipase gene(s) from various other plant
species. Indeed, as demonstrated herein, oligonucleotide primers
based on the carnation cDNA sequence have been successfully used to
generate tomato leaf senescence-induced lipase gene fragments by
polymerase chain reactions using tomato leaf genomic DNA as
template.
[0066] The cloned senescence-induced lipase gene(s) or fragment(s)
thereof, alone or in combination, when introduced in reverse
orientation (antisense) under control of a constitutive promoter,
such as the fig wart mosaic virus 35S promoter, the cauliflower
mosaic virus promoter CaMV35S or the MAS promoter, can be used to
genetically modify plants and alter senescence in the modified
plants. Selected antisense sequences from other plants which share
sufficient sequence identity with the carnation senescence-induced
lipase gene can be used to achieve similar genetic modification.
One result of the genetic modification is a reduction in the amount
of endogenous translatable senescence-induced lipase-encoding mRNA.
Consequently, the amount of senescence-induced lipase produced in
the plant cells is reduced, thereby reducing the amount of cell
membrane damage and cell leakage, e.g., reduced leaf, fruit and/or
flower senescence and spoilage, due to aging or environmental
stress.
[0067] For example, Arabidopsis plants transformed with vectors
that express the full-length Arabidopsis senescence-induced lipase
gene in antisense orientation, under regulation of double 35S
promoter exhibit larger leaf size and overall larger plant growth
as compared to wild-type plants as shown in FIGS. 11 and 18. These
plants also demonstrate delayed leaf senescence, as shown in FIG.
19.
[0068] The effect of reduced expression of the senescence-induced
lipase gene brought about by expressing the full-length lipase gene
in antisense orientation in transgenic Arabidopsis plants is also
seen as an increase in seed yield in the transformed plants.
Arabidopsis plant lines expressing the full-length
senescence-induced lipase gene produce up to about two to three
times more seed than wild type plants. (FIG. 20)
[0069] That the effects observed in transgenic plants on biomass,
leaf senescence and seed yield are due to a decrease in
senescence-induced lipase in these plants is shown in FIG. 21. The
transgenic plants of the invention exhibit significantly reduced
expression of senescence-induced lipase in comparison to wild-type
plants.
[0070] Thus, the methods and sequences of the present invention can
be used to delay plant spoilage, including leaf or fruit spoilage,
as well as to increase plant biomass and seed yield, and in
general, alter senescence in plants.
[0071] The isolated nucleotide sequences of this invention can be
used to isolate substantially complementary senescence-induced
lipase nucleotide sequence from other plants or organisms. These
sequences can, in turn, be used to transform plants and thereby
alter senescence of the transformed plants in the same manner as
shown with the use of the isolated nucleotide sequences shown
herein.
[0072] The genetic modifications observed with transformation of
plants with senescence-induced lipase, functional fragments thereof
or combinations thereof can effect a permanent change in levels of
senescence-induced lipase in the plant and be propagated in
offspring plants by selfing or other reproductive schemes. The
genetically altered plant is used to produce a new line of plants
wherein the alteration is stably transmitted from generation to
generation. The present invention provides for the first time the
appropriate DNA sequences which may be used to achieve a stable
genetic modification of senescence in a wide range of different
plants.
[0073] For the identification and isolation of the
senescence-induced lipase gene, in general, preparation of plasmid
DNA, restriction enzyme digestion, agarose gel electrophoresis of
DNA, polyacrylamide gel electrophoresis of protein, Southern blots,
Northern blots, DNA ligation and bacterial transformation were
carried out using conventional methods well-known in the art. See,
for example, Sambrook, J. et al., Molecular Cloning: A Laboratory
Manual, 2nd ed., Cold Spring Harbor Press, Cold Spring Harbor,
N.Y., 1989. Techniques of nucleic acid hybridization are disclosed
by Sambrook (Supra).
[0074] As used herein, the term "plant" refers to either a whole
plant, a plant part, a plant cell or a group of plant cells. The
type of plant which can be used in the method of the invention is
not limited and includes, for example, ethylene-sensitive and
ethylene-insensitive plants; fruit bearing plants such as apricots,
apples, oranges, bananas, grapefruit, pears, tomatoes,
strawberries, avocados, etc.; vegetables such as carrots, peas,
lettuce, cabbage, turnips, potatoes, broccoli, asparagus, etc.;
flowers such as carnations, roses, mums, etc.; and in general, any
plant that can take up and express the DNA molecules of the present
invention. It may include plants of a variety of ploidy levels,
including haploid, diploid, tetraploid and polyploid.
[0075] A transgenic plant is defined herein as a plant which is
genetically modified in some way, including but not limited to a
plant which has incorporated heterologous or homologous
senescence-induced lipase DNA or modified DNA or some portion of
heterologous senescence-induced lipase DNA or homologous
senescence-induced lipase DNA into its genome. The altered genetic
material may encode a protein, comprise a regulatory or control
sequence, or may be or include an antisense sequence or encode an
antisense RNA which is antisense to the endogenous
senescence-induced lipase DNA or mRNA sequence or portion thereof
of the plant. A "transgene" or "transgenic sequence" is defined as
a foreign gene or partial sequence which has been incorporated into
a transgenic plant.
[0076] The term "hybridization" as used herein is generally used to
mean hybridization of nucleic acids at appropriate conditions of
stringency as would be readily evident to those skilled in the art
depending upon the nature of the probe sequence and target
sequences. Conditions of hybridization and washing are well known
in the art, and the adjustment of conditions depending upon the
desired stringency by varying incubation time, temperature and/or
ionic strength of the solution are readily accomplished. See, for
example, Sambrook, J. et al., Molecular Cloning: A Laboratory
Manual, 2nd edition, Cold spring harbor Press, Cold Spring harbor,
New York, 1989. The choice of conditions is dictated by the length
of the sequences being hybridized, in particular, the length of the
probe sequence, the relative G-C content of the nucleic acids and
the amount of mismatches to be permitted. Low stringency conditions
are preferred when partial hybridization between strands that have
lesser degrees of complementarity is desired. When perfect or near
perfect complementarity is desired, high stringency conditions are
preferred. For typical high stringency conditions, the
hybridization solution contains 6.times.S.S.C., 0.01 M EDTA,
1.times. Denhardt's solution and 0.5% SDS. Hybridization is carried
out at about 68.degree. C. for about 3 to 4 hours for fragments of
cloned DNA and for about 12 to about 16 hours for total eukaryotic
DNA. For lower stringencies the temperature of hybridization is
reduced to about 12.degree. C. below the melting temperature
(T.sub.M) of the duplex. The T.sub.M is known to be a function of
the G-C content and duplex length as well as the ionic strength of
the solution.
[0077] As used herein, the term "substantial sequence identity" or
"substantial homology" is used to indicate that a nucleotide
sequence or an amino acid sequence exhibits substantial structural
or functional equivalence with another nucleotide or amino acid
sequence. Any structural or functional differences between
sequences having substantial sequence identity or substantial
homology will be de minimis; that is, they will not affect the
ability of the sequence to function as indicated in the desired
application. Differences may be due to inherent variations in codon
usage among different species, for example. Structural differences
are considered de minimis if there is a significant amount of
sequence overlap or similarity between two or more different
sequences or if the different sequences exhibit similar physical
characteristics even if the sequences differ in length or
structure. Such characteristics include for example, ability to
hybridize under defined conditions, or in the case of proteins,
immunological crossreactivity, similar enzymatic activity, etc.
[0078] Additionally, two nucleotide sequences are "substantially
complementary" if the sequences have at least about 40 percent,
more preferably, at least about 60 percent and most preferably
about 90 percent sequence similarity between them. Two amino acid
sequences are substantially homologous if they have at least 40%,
preferably 70% similarity between the active portions of the
polypeptides.
[0079] As used herein, the phrase "hybridizes to a corresponding
portion" of a DNA or RNA molecule means that the molecule that
hybridizes, e.g., oligonucleotide, polynucleotide, or any
nucleotide sequence (in sense or antisense orientation) recognizes
and hybridizes to a sequence in another nucleic acid molecule that
is of approximately the same size and has enough sequence
similarity thereto to effect hybridization under appropriate
conditions. For example, a 100 nucleotide long antisense molecule
from the 3' coding or non-coding region of carnation lipase will
recognize and hybridize to an approximately 100 nucleotide portion
of a nucleotide sequence within the 3' coding or non-coding region,
respectively of the Arabidopsis senescence-induced lipase gene or
any other plant senescence-induced lipase gene so long as there is
about 70% or more sequence similarity between the two sequences. It
is to be understood that the size of the "corresponding portion"
will allow for some mismatches in hybridization such that the
"corresponding portion" may be smaller or larger than the molecule
which hybridizes to it, for example 20-30% larger or smaller,
preferably no more than about 12-15% larger or smaller.
[0080] The term "functional derivative" of a nucleic acid (or poly-
or oligonucleotide) is used herein to mean a fragment, variant,
homolog, or analog of the gene or nucleotide sequence encoding
senescence-induced lipase. A functional derivative may retain at
least a portion of the function of the senescence-induced lipase
encoding DNA which permits its utility in accordance with the
invention. Such function may include the ability to hybridize with
native carnation senescence-induced lipase or substantially
homologous DNA from another plant which encodes senescence-induced
lipase or with an mRNA transcript thereof, or, in antisense
orientation, to inhibit the transcription and/or translation of
plant senescence-induced lipase mRNA, or the like.
[0081] A "fragment" of the gene or DNA sequence refers to any
subset of the molecule, e.g., a shorter polynucleotide or
oligonucleotide. A "variant" refers to a molecule substantially
similar to either the entire gene or a fragment thereof, such as a
nucleotide substitution variant having one or more substituted
nucleotides, but which maintains the ability to hybridize with the
particular gene or to encode mRNA transcript which hybridizes with
the native DNA. A "homolog" refers to a fragment or variant
sequence from a different plant genus or species. An "analog"
refers to a non-natural molecule substantially similar to or
functioning in relation to either the entire molecule, a variant or
a fragment thereof.
[0082] By "altered expression" or "modified expression" of a gene,
e.g., the senescence-induced lipase gene, is meant any process or
result whereby the normal expression of the gene, for example, that
expression occurring in an unmodified carnation or other plant, is
changed in some way. As intended herein, alteration in gene
expression is complete or partial reduction in the expression of
the senescence-induced lipase gene, but may also include a change
in the timing of expression, or another state wherein the
expression of the senescence-induced lipase gene differs from that
which would be most likely to occur naturally in an unmodified
plant or cultivar. A preferred alteration is one which results in
reduction of senescence-induced lipase production by the plant
compared to production in an unmodified plant.
[0083] In producing a genetically altered plant in accordance with
this invention, it is preferred to select individual plantlets or
plants by the desired trait, generally reduced senescence-induced
lipase expression or production. Expression of senescence-induced
lipase can be quantitated, for example in a conventional
immunoassay method using a specific antibody as described herein.
Also, senescence-induced lipase enzymatic activity can be measured
using biochemical methods as described herein.
[0084] In order for a newly inserted gene or DNA sequence to be
expressed, resulting in production of the protein which it encodes,
or in the case of antisense DNA, to be transcribed, resulting in an
antisense RNA molecule, the proper regulatory elements should be
present in proper location and orientation with respect to the gene
or DNA sequence. The regulatory regions may include a promoter, a
5'-non-translated leader sequence and a 3'-polyadenylation sequence
as well as enhancers and other regulatory sequences.
[0085] Promoter regulatory elements that are useful in combination
with the senescence-induced lipase gene to generate sense or
antisense transcripts of the gene include any plant promoter in
general, and more particularly, a constitutive promoter such as the
fig wart mosaic virus 35S promoter, double 35S promoter, the
cauliflower mosaic virus promoter, CaMV35S promoter, or the MAS
promoter, or a tissue-specific or senescence-induced promoter, such
as the carnation petal GST1 promoter or the Arabidopsis SAG12
promoter (See, for example, J. C. Palaqui et al., Plant Physiol.,
112:1447-1456 (1996); Morton et al., Molecular Breeding, 1:123-132
(1995); Fobert et al., Plant Journal, 6:567-577 (1994); and Gan et
al., Plant Physiol., 113:313 (1997), incorporated herein by
reference). Preferably, the promoter used in the present invention
is a constitutive promoter.
[0086] Expression levels from a promoter which is useful for the
present invention can be tested using conventional expression
systems, for example by measuring levels of a reporter gene
product, e.g., protein or mRNA in extracts of the leaves, flowers,
fruit or other tissues of a transgenic plant into which the
promoter/reporter have been introduced.
[0087] The present invention provides antisense oligonucleotides
and polynucleotides complementary to the gene encoding carnation
senescence-induced lipase, complementary to the gene encoding
Arabidopsis senescence-induced lipase or complementary to a gene or
gene fragment from another plant, which hybridizes with the
carnation or Arabidopsis senescence-induced lipase gene under low
to high stringency conditions. Such antisense oligonucleotides
should be at least about six nucleotides in length to provide
minimal specificity of hybridization and may be complementary to
one strand of DNA or mRNA encoding senescence-induced lipase or a
portion thereof, or to flanking sequences in genomic DNA which are
involved in regulating senescence-induced lipase gene expression.
The antisense oligonucleotide may be as large as 100 nucleotides
and may extend in length up to and beyond the full coding sequence
for which it is antisense. The antisense oligonucleotides can be
DNA or RNA or chimeric mixtures of DNA and RNA or derivatives or
modified versions thereof, single stranded or double stranded.
[0088] The action of the antisense oligonucleotide may result in
alteration, primarily inhibition, of senescence-induced lipase gene
expression in cells. For a general discussion of antisense see:
Alberts, et al., Molecular Biology of the Cell, 2nd ed., Garland
Publishing, Inc. New York, N.Y. (1989, in particular pages 195-196,
incorporated herein by reference).
[0089] The antisense oligonucleotide may be complementary to any
portion of the senescence-induced lipase gene. In one embodiment,
the antisense oligonucleotide may be between 6 and 100 nucleotides
in length, and may be complementary to the 5'-non-coding sequence
or 3' end of the senescence-induced lipase sequence, for example.
Antisense oligonucleotides primarily complementary to 5'-non-coding
sequences are known to be effective inhibitors of expression of
genes encoding transcription factors. Branch, M. A., Molec. Cell
Biol., 13:4284-4290 (1993).
[0090] Preferred antisense oligonucleotides are substantially
complementary to a corresponding portion of the mRNA encoding
senescence-induced lipase. For example, introduction of the full
length cDNA clone encoding senescence-induced lipase in an
antisense orientation into a plant is expected to result in
successful altered senescence-induced lipase gene expression.
Moreover, introduction of partial sequences, targeted to specific
portions of the senescence-induced lipase gene, can be equally
effective.
[0091] The minimal amount of homology required by the present
invention is that sufficient to result in sufficient
complementarity to provide recognition of the specific target RNA
or DNA and inhibition or reduction of its translation or function
while not affecting function of other RNA or DNA molecules and the
expression of other genes. While the antisense oligonucleotides of
the invention comprise sequences complementary to at least a
portion of an RNA transcript of the senescence-induced lipase gene,
absolute complementarity, although preferred is not required. The
ability to hybridize may depend on the length of the antisense
oligonucleotide and the degree of complementarity. Generally, the
longer the hybridizing nucleic acid, the more base mismatches with
the senescence-induced lipase target sequence it may contain and
still form a stable duplex. One skilled in the art can ascertain a
tolerable degree of mismatch by use of standard procedures to
determine the melting temperature of the hybridized complex, for
example.
[0092] The antisense RNA oligonucleotides may be generated
intracellularly by transcription from exogenously introduced
nucleic acid sequences. The antisense molecule may be delivered to
a cell by transformation or transfection or infection with a
vector, such as a plasmid or virus into which is incorporated DNA
encoding the antisense senescence-induced lipase sequence operably
linked to appropriate regulatory elements, including a promoter.
Within the cell the exogenous DNA sequence is expressed, producing
an antisense RNA of the senescence-induced lipase gene.
[0093] Vectors can be plasmids, preferably, or may be viral or
other vectors known in the art to replicate and express genes
encoded thereon in plant cells or bacterial cells. The vector
becomes chromosomally integrated such that it can be transcribed to
produce the desired antisense senescence-induced lipase RNA. Such
plasmid or viral vectors can be constructed by recombinant DNA
technology methods that are standard in the art. For example, the
vector may be a plasmid vector containing a replication system
functional in a prokaryotic host and an antisense oligonucleotide
or polynucleotide according to the invention. Alternatively, the
vector may be a plasmid containing a replication system functional
in Agrobacterium and an antisense oligonucleotide or polynucleotide
according to the invention. Plasmids that are capable of
replicating in Agrobacterium are well known in the art. See, Miki,
et al., Procedures for Introducing Foreign DNA Into Plants, Methods
in Plant Molecular Biology and Biotechnology, Eds. B. R. Glick and
J. E. Thompson. CRC Press (1993), PP. 67-83.
[0094] The carnation lipase gene was cloned in the antisense
orientation into a plasmid vector in the following manner. The pCD
plasmid, which is constructed from a pUC18 backbone and contains
the 35S promoter from cauliflower mosaic virus (CaMV) followed by a
multiple cloning site and an octapine synthase termination sequence
was used for cloning the carnation lipase gene. The pCd-lipase
(antisense) plasmid was constructed by subcloning the full length
carnation lipase gene in the antisense orientation into a Hind3
site and EcoR1 site of pCd. Similarly, a pCD.DELTA.35S-GST1-lipase
(antisense) plasmid was constructed by first subcloning a PCR
amplified fragment (-703 to +19 bp) of the carnation Glutathione S
Transferase 1 (GST1) promoter into the BamH1 and Sal1 sites of the
pCd vector. The full length carnation lipase gene was then
subcloned in the antisense orientation into the Hind3 and EcoR1
sites of the construct. Another plasmid, pGd.DELTA.35S-GST1-GUS
plasmid, was constructed by first subcloning a PCR-amplified
fragment (-703 to +19 bp) of the carnation Glutathione
S-Transferase 1 (GST1) promoter into the BamH1 and Sal1 sites of
the pCd vector. The reporter gene beta-glucuronidase (GUS) was then
subcloned into the Sal1 and EcoRI sites of the construct. The
pCd-35S.sup.2-lipase (antisense) plasmid was constructed by first
subcloning a double 35S promoter (containing two copies of the CaMV
35S promoter in tandem) into the Sma1 and Hind3 sites of the pCd
vector. The full length carnation lipase gene was then subcloned in
the antisense orientation into the Hind3 and EcoR1 sites of the
construct.
[0095] An oligonucleotide, preferably between about 6 and about 100
nucleotides in length and complementary to the target sequence of
senescence-induced lipase, may be prepared by recombinant
nucleotide technologies or may be synthesized from mononucleotides
or shorter oligonucleotides, for example. Automated synthesizers
are applicable to chemical synthesis of the oligo- and
polynucleotides of the invention. Procedures for constructing
recombinant nucleotide molecules in accordance with the present
invention are disclosed in Sambrook, et al., In: Molecular Cloning:
A Laboratory Manual, 2nd ed., Cold Spring Harbor Press, Cold Spring
Harbor, N.Y. (1989), which is incorporated herein in its entirety.
Oligonucleotides which encode antisense RNA complementary to
senescence-induced lipase sequence can be prepared using procedures
well known to those in the art. Details concerning such procedures
are provided in Maniatis, T. et al., Molecular mechanisms in the
Control of Gene expression, eds., Nierlich, et al., eds., Acad.
Press, N.Y. (1976).
[0096] In an alternative embodiment of the invention, inhibition of
expression of endogenous plant senescence-induced lipase is the
result of co-suppression through over-expression of an exogenous
senescence-induced lipase gene or gene fragment introduced into the
plant cell. In this embodiment of the invention, a vector encoding
senescence-induced lipase in the sense orientation is introduced
into the cells in the same manner as described herein for antisense
molecules. Preferably, the senescence-induced lipase is operatively
linked to a strong constitutive promoter, such as for example the
fig wart mosaic virus promoter or CaMV35S.
[0097] Transgenic plants made in accordance with the present
invention may be prepared by DNA transformation using any method of
plant transformation known in the art. Plant transformation methods
include direct co-cultivation of plants, tissues or cells with
Agrobacterium tumerfaciens or direct infection (Miki, et al., Meth.
in Plant Mol. Biol. and Biotechnology, (1993), p. 67-88); direct
gene transfer into protoplasts or protoplast uptake (Paszkowski, et
al., EMBO J., 12:2717 (1984); electroporation (Fromm, et al.,
Nature, 319:719 (1986); particle bombardment (Klein et al.,
BioTechnology, 6:559-563 (1988); injection into meristematic
tissues of seedlings and plants (De LaPena, et al., Nature,
325:274-276 (1987); injection into protoplasts of cultured cells
and tissues (Reich, et al., BioTechnology, 4:1001-1004 (1986)).
[0098] Generally a complete plant is obtained from the
transformation process. Plants are regenerated from protoplasts,
callus, tissue parts or explants, etc. Plant parts obtained from
the regenerated plants in which the expression of
senescence-induced lipase is altered, such as leaves, flowers,
fruit, seeds and the like are included in the definition of "plant"
as used herein. Progeny, variants and mutants of the regenerated
plants are also included in the definition of "plant."
[0099] The present invention also provides carnation or Arabidopsis
senescence-induced lipase protein encoded by the cDNA molecules of
the invention and proteins which cross-react with antibody to the
carnation or Arabidopsis protein. Such proteins have the amino acid
sequence set forth in SEQ ID No:2, shown in FIG. 1, share cross
reactivity with antibodies to the protein set forth in SEQ ID NO:2,
have the amino acid sequence set forth in SEQ ID NO:19 (shown in
FIG. 14) or share cross reactivity with antibodies to the protein
set forth in SEQ ID NO:19.
[0100] The carnation or Arabidopsis senescence-induced lipase
protein or functional derivatives thereof are preferably produced
by recombinant technologies, optionally in combination with
chemical synthesis methods. In one embodiment of the invention the
senescence-induced lipase is expressed as a fusion protein
consisting of the senescence-induced lipase fused with maltose
binding protein. Expression of a clone encoding the recombinant
fusion protein yields a fusion protein of the expected molecular
weight that hydrolyzes p-nitrophenylpalmitate, phospholipid and
triacylglycerol, which is an indicator of lipase activity. The
recombinant senescence-induced lipase protein shows a predominant
band in Western blot analyses after immunoblotting with antibody to
carnation senescence-induced lipase. The free senescence-induced
lipase (50.2 Kda), which is released by treatment of the fusion
protein with the protease, factor Xa, also reacts with the
senescence-induced lipase antibody in Western blot analysis (FIG.
3). A motif search of the senescence-induced lipase amino acid
sequence shows the presence of a potential N-myristoylation site
(FIG. 1) for the covalent attachment of myristate via an amide
linkage (See Johnson, et al., Ann. Rev. Biochem., 63: 869-914
(1994); Towler, et al., Ann. Rev. Biochem., 57:67-99 (1988); and R.
J. A. Grand, Biochem. J., 258:625-638 (1989). The protein motif
search also showed that the carnation senescence-induced lipase
contains a sequence, ITFAGHSLGA, (SEQ ID NO:4) which is the
conserved lipase consensus sequence (Table 1). The conserved lipase
consensus sequence from a variety of plants is shown in the table
below. TABLE-US-00001 TABLE 1 Plant Species conserved Lipase
Sequence Carnation I T F A G H S L G A (SEQ ID NO: 4) Tomato I T F
T G H S L G A (SEQ ID NO: 3) Arabidopsis I T T C G H S L G A (SEQ
ID NO: 9) Ipomoea nil I T V T G H S L G S (SEQ ID NO: 10)
[0101] The senescence-induced lipase protein of the invention was
shown to possess lipase activity in both in vitro and in situ
assays. For in vitro measurements, p-nitrophenylpalmitate and
soybean phospholipid (40% phosphatidylcholine and 60% other
phospholipids) were used as substrates, and the products of the
reactions, p-nitrophenol and free fatty acids, respectively, were
measured spectrophotometrically (Pencreac'h and Baratti, 1996;
Nixon and Chan, 1979; Lin et al., 1983). Lipase activity was also
measured in vitro by gas chromatography using a modification of the
method described by Nixon and Chan (1979) and Lin et al. (1983).
The reaction mixture contained 100 mM Tris-HCl (pH 8.0), 2.5 mM
substrate (trilinolein, soybean phospholipid or
dilinoleylphosphatidylcholine) and enzyme protein (100 .mu.g) in a
final volume of 100 .mu.l. The substrates were emulsified in 5% gum
arabic prior to being added to the reaction mixture. To achieve
this, the substrates were dissolved in chloroform, added to the gum
arabic solution and emulsified by sonication for 30 s. After
emulsification, the chloroform was evaporated by a stream of
N.sub.2. The reaction was carried out at 25.degree. C. for varying
periods of time up to 2 hours. The reaction mixture was then
lipid-extracted, and the free fatty acids were purified by TLC,
derivitized and quantified by GC (McKegney et al., 1995).
[0102] Lipolytic acyl hydrolase activity was measure in situ as
described by Furukawa et al. (1983) and modified by Tsuboi et al.
(1996). In this latter assay, E. coli transformed with the full
length cDNA clone encoding senescence-induced lipase were grown in
minimal salt medium supplemented with Tween 40 or Tween 60, both of
which are long chain fatty acid esters, as the only source of
carbon. Thus, carbon for bacterial growth was only available if the
fatty acid esters were hydrolyzed by lipase. The finding that E.
coli transformed with the senescence-induced lipase cDNA grow in
Tween 40- and Tween 60-basal medium after an initial lag phase,
whereas control cultures of E. coli that were not transformed do
not grow, confirms the lipase activity of the encoded recombinant
protein (FIG. 5). That is, the senescence-induced lipase releases
stearate (Tween 60) and palmitate (Tween 40) to obtain the
necessary carbon for growth.
[0103] "Functional derivatives" of the senescence-induced lipase
protein as described herein are fragments, variants, analogs, or
chemical derivatives of senescence-induced lipase, which retain at
least a portion of the senescence-induced lipase activity or
immunological cross reactivity with an antibody specific for
senescence-induced lipase. A fragment of the senescence-induced
lipase protein refers to any subset of the molecule. Variant
peptides may be made by direct chemical synthesis, for example,
using methods well known in the art. An analog of
senescence-induced lipase refers to a non-natural protein
substantially similar to either the entire protein or a fragment
thereof. Chemical derivatives of senescence-induced lipase contain
additional chemical moieties not normally a part of the peptide G38
or peptide fragment. Modifications may be introduced into the
senescence-induced lipase peptide or fragment thereof by reacting
targeted amino acid residues of the peptide with an organic
derivatizing agent that is capable of reacting with selected side
chains or terminal residues.
[0104] A senescence-induced lipase protein or peptide according to
the invention may be produced by culturing a cell transformed with
a nucleotide sequence of this invention (in the sense orientation),
allowing the cell to synthesize the protein and then isolating the
protein, either as a free protein or as a fusion protein, depending
on the cloning protocol used, from either the culture medium or
from cell extracts. Alternatively, the protein can be produced in a
cell-free system. Ranu, et al., Meth. Enzymol., 60:459-484,
(1979).
[0105] Having now generally described the invention, the same will
be more readily understood through reference to the following
examples which are provided by way of illustration, and are not
intended to be limiting to the present invention.
EXAMPLE 1
Plant Materials Used to Isolate the Carnation Lipase cDNA
[0106] Carnation plants (Dianthus caryophyllus L. cv. Improved
white Sim) grown and maintained in a greenhouse were used to
isolate the nucleotide sequence corresponding to the
senescence-induced lipase gene. Flower tissue in the form of
senescing flower petals (from different developmental stages) was
collected in buffer or stored at -70.degree. C. until used.
[0107] Cytosolic lipid particles were isolated from carnation
flower petals harvested just before the onset of senescence.
Carnation petals (25 g/150 ml buffer) were homogenized at 4.degree.
C. in homogenization buffer (50 mM Epps-0.25 M sorbitol pH 7.4, 10
mm EDTA, 2 mM EGTA, 1 mM PMSF, 1 mM benzamadine, 10 mm
amino-n-caproic acid and 4% polyvinylpolypyrrolidone) for 45
seconds in an Omnimizer and for an additional minute in a Polytron
homogenizer. The homogenate was filtered through four layers of
cheesecloth, and the filtrate was centrifuged at 10,000 g for
twenty minutes at 4.degree. C. The supernatant was centrifuged for
one hour at 250,000 g to isolate microsomal membranes. The lipid
particles were obtained from the post-microsomal supernatant by
collecting the particles after floatation centrifugation by the
method of Hudak and Thompson, (1997), Physiol. Plant., 114:705-713.
The supernatant was made 10% (w/v) with sucrose, and 23 ml of the
supernatant were poured into 60 Ti Beckman centrifuge tubes,
overlayed with 1.5 ml isolation buffer and centrifuged at 305,000 g
for 12 hours at 4.degree. C. The particles were removed from the
isolation buffer overlayer with a Pasteur pipette. Three ml of
particle suspension were loaded onto a Sepharose G-25 column
equilibrated with sterile PBS (10 mM sodium phosphate buffer pH 7.5
plus 0.85% sodium chloride) and the suspension was eluted with
sterile PBS. The void volume containing the particles was eluted
and concentrated using a Centricon-10 filter (available from
Amicon) to a protein concentration of 600 .mu.g. The lipid
particles were then used to generate antibodies in rabbits
inoculated with 300 .mu.g of the particles. The IgG titer of the
blood was tested by Western blot analysis.
Messenger RNA (mRNA) Isolation
[0108] Total RNA was isolated from petals of stage I, II, III or IV
carnation flowers essentially as described by Chomczynski and
Sachi, Anal. Biochem., 162:156-159 (1987). Briefly, 15 g of petal
tissue were frozen in liquid nitrogen and homogenized for 30
seconds in buffer containing 4 M guanidinium thiocyanate, 25 mM
sodium citrate, pH 7.0, 0.5% sarkosyl and 0.1 M
.beta.-mercaptoethanol. 150 ml water-saturated phenol, 30 ml of
chloroform and 15 ml of 2 M NaOAc, pH 4.0 were added to the
homogenized sample. The sample was centrifuged at 10,000 g for ten
minutes and the aqueous phase removed and nucleic acids
precipitated therefrom with 150 ml isopropanol. The sample was
centrifuged for ten minutes at 5,000 g and the pellet was washed
once with 30 ml of 4 M LiCl, extracted with 30 ml chloroform and
precipitated with 30 ml isopropanol containing 0.2 M NaOAc, pH 5.0.
The RNA was dissolved in DEPC-treated water and stored at
-70.degree. C.
[0109] PolyA.sup.+ mRNA was isolated from total RNA using the
PolyA.sup.+ tract mRNA Isolation System available from Promega.
PolyA.sup.+ mRNA was used as a template for cDNA synthesis using
the ZAP Express.RTM. cDNA synthesis system available from
Stratagene (La Jolla, Calif.)
Carnation Petal cDNA Library Screening
[0110] A cDNA library made using mRNA isolated from stage IV
carnation petals was diluted to approximately 5.times.10.sup.6
PFU/ml and immunoscreened with lipid particle antiserum. Positive
cDNA clones were recovered using the ExAssist.RTM. Helper
Phage/SOLR strain system and recircularized in a pBluescript.RTM.
phagemid (Stratagene). A stage III carnation petal cDNA library was
also screened using a .sup.32P-labelled 19 base pair probe
(5'-ACCTACTAGGTTCCGCGTC-3') (SEQ ID NO:5). Positive cDNA clones
were excised from the phages and recircularized into a pBK-CMV.RTM.
(Stratagene) phagemid using the method in the manufacturer's
instructions. The full length cDNA (1.53 kb fragment) was inserted
into the pBK-CMV vector.
Arabidopsis Leaf cDNA Library Screening
[0111] A full-length cDNA clone (1338 bp) of the senescence-induced
lipase gene from Arabidopsis thaliana was isolated by screening an
Arabidopsis senescent leaf cDNA library. The probe used for
screening the library was obtained by PCR using the senescent leaf
library as template. The PCR primers were designed from the genomic
sequence (U93215) present in GenBank. The forward primer had the
sequence 5' ATG TCT AGA GAA GAT ATT GCG CGG CGA 3' (SEQ ID NO:20)
and the reverse primer had the sequence 5' GAT GAG CTC GAC GGA GCT
GAG AGA GAT G 3' (SEQ ID NO:21). The PCR product was subcloned into
Bluescript for sequencing. The nucleotide and amino acid sequence
of the PCR product used are shown in FIG. 14.
Plasmid DNA Isolation, DNA Sequencing
[0112] The alkaline lysis method described by Sambrook et al.,
(Supra) was used to isolate plasmid DNA. The full length positive
cDNA clone was sequenced using the dideoxy sequencing method.
Sanger, et al., Proc. Natl. Acad. Sci. USA, 74:5463-5467. The open
reading frame was compiled and analyzed using BLAST search
(GenBank, Bethesda, Md.) and alignment of the five most homologous
proteins with the derived amino acid sequence of the encoded gene
was achieved using a BCM Search Launcher: Multiple Sequence
Alignments Pattern-Induced Multiple Alignment Method (See F.
Corpet, Nuc. Acids Res., 16:10881-10890, (1987)). Functional motifs
present in the derived amino acid sequence were identified by
MultiFinder.
Expression of the Lipase as a Fusion Protein
[0113] Phagemid pBK-CMV containing the full length carnation
senescence-induced lipase was digested with EcoRI and XbaI, which
released the 1.53 Kb lipase fragment, which was subcloned into an
EcoRI and XbaI digested fusion vector, pMalc (New England BioLabs).
The pMalc vector containing the senescence-induced lipase,
designated pMLip, was used to transform E. coli BL-21 (DE3)
cells.
[0114] The fusion protein encoded by pMLip, (fusion of the
senescence-induced lipase and maltose binding protein) was isolated
and purified as described in Sambrook, et al. (Supra) and Ausubel,
et al., in Current Protocols in Molecular Biology, Green Publishing
Associates and Wiley Interscience, New York, (1987), 16.4.1-16.4.3.
Briefly, E. coli BL-21 cells transformed with pMLip were
resuspended in 3 ml/g lysate buffer (50 mM Tris, pH 8.0, 100 mM
NaCl and 1 mM EDTA) containing 8 .mu.l of 50 mM PMSF and 80 .mu.l
of 20 mg/ml lysozyme per gram of cells and incubated for twenty
minutes at room temperature with shaking. Then, 80 .mu.l of 5%
deoxycholic acid and 40 units of DNAse I were added and the cells
were shaken at room temperature until the cells completely lysed.
The cell debris was pelleted by centrifugation and resuspended in
two volumes of lysate buffer plus 8 M urea and 0.1 mM PMSF. After
one hour, seven volumes of buffer (50 mM KH.sub.2PO.sub.4, 1 mM
EDTA and 50 mM NaCl, pH 7.0) were added to neutralize the
suspension. The pH of the cell suspension was adjusted to pH 8.0
with HCl and the cell debris was pelleted. The supernatant was
dialyzed against 20 mM Tris buffer, pH 8.0, 100 mM NaCl and 1 mM
EDTA at 4.degree. C. overnight. The maltose binding protein-lipase
fusion product (Malip) was purified using an amylose column
(available from New England BioLab) Fractions containing the fusion
protein were cleaved with Protease Factor Xa (1 .mu.g/100 .mu.g
fusion protein) to separate lipase from the fusion product. Both
the fusion protein and the cleaved lipase were analyzed by SDS PAGE
electrophoresis and Western blots. Maltose binding protein encoded
by pMalc was used as a control. The results are shown in FIG.
3.
Northern Blot Hybridizations of Carnation RNA
[0115] Ten .mu.g of total RNA isolated from flowers at stages I,
II, III, IV were separated on 1% denatured formaldehyde agarose
gels and immobilized on nylon membranes. The 1.53 Kb EcoRI-XbaI
lipase fragment labelled with .sup.32P-dCTP using a random primer
kit (Boehringer Mannheim) was used to probe the filters
(7.times.10.sup.7 cpm). The filters were washed once with
1.times.SSC, 0.1% SDS at room temperature and three times with
0.2.times.SSC, 0.1% SDS at 65.degree. C. The filters were dried and
exposed to X-ray film overnight at -70.degree. C. The results are
shown in FIG. 4.
Northern Blot Hybridization of Arabidopsis RNA
[0116] Ten .mu.g of total RNA isolated from Arabidopsis leaves at
weeks 2, 3, 4, 5 and 6 of growth were separated on 1% denatured
formaldehyde agarose gels and immobilized on nylon membranes. The
full-length Arabidopsis senescence-induced lipase gene labelled
with .sup.32P-dCTP using a random primer kit (Boehringer Mannheim)
was used to probe the filters (7.times.10.sup.7 cpm). The filters
were washed once with 1.times.SSC, 0.1% SDS at room temperature and
three times with 0.2.times.SSC, 0.1% SDS at 65.degree. C. The
filters were dried and exposed to X-ray film overnight at
-70.degree. C.
Genomic DNA Isolation and Southern Blot Hybridizations
[0117] Freshly cut carnation petals were frozen in liquid nitrogen,
ground to a powder and homogenized (2 ml/g) with extraction buffer
(0.1 M Tris, pH 8.2, 50 mM EDTA, 0.1M NaCl, 2% SDS, and 0.1 mg/ml
proteinase K) to isolate genomic DNA. The homogenized material was
incubated at 37.degree. C. for ten minutes and extracted with
phenol-chloroform-isoamyl alcohol (25:24:1). DNA was precipitated
with NaOAc and isopropanol. The DNA pellet was dissolved in
1.times.TE, pH 8.0, re-extracted with phenol, reprecipitated and
resuspended in 1.times.TE, pH 8.0.
[0118] Genomic DNA was digested with restriction endonucleases (Bam
HI, XbaI, XhoI, EcoRI, HindIII and SalI) separately and the
digested DNA was fractionated on a 1% agarose gel. The separated
DNA was blotted onto nylon membranes and hybridizations were
carried out using .sup.32P-dCTP-labelled 1.53 Kb lipase fragment.
Hybridization and washing were carried out under high stringency
conditions (68.degree. C.))6.times. SSC, 2.times.Denhardt's
reagent, 0.1% SDS) as well as low stringency conditions (42.degree.
C. for hybridization and washing) (6.times.SSC, 5.times. Denhardt's
reagent, 0.1% SDS). The results are shown in FIG. 6. As can be
seen, the lipase cDNA probe detects only one genomic fragment,
indicating that the carnation lipase gene is a single copy
gene.
Lipase Enzyme Assays
[0119] Lipolytic acyl hydrolase activity of the purified lipase
fusion protein was assayed spectrophotometrically using
p-nitrophenylpalmitate and soybean phospholipid as exogenous
substrates. For maltose-binding protein alone, which served as a
control, there was no detectable lipase activity with phospholipid
as a substrate (Table 2). When p-nitrophenylpalmitate was used as a
substrate with maltose-binding protein alone, a small amount of
p-nitrophenol, the expected product of a lipase reaction, was
detectable reflecting background levels of p-nitrophenol in the
commercial preparation of p-nitrophenylpalmitate (Table 2).
However, in the presence of purified lipase fusion protein, strong
lipase activity manifested as the release of free fatty acids from
phospholipid and p-nitrophenol from p-nitrophenylpalmitate was
evident (Table 2). TABLE-US-00002 TABLE 2 Spectrophotometric
measurements of the lipolytic acyl hydrolase activity of
maltose-binding protein and lipase fusion protein expressed in E.
coli and purified by amylose column chromatography. Two substrates,
p-nitrophenylpalmitate and soybean phospholipid, were used.
Activities are expressed in terms of product formed (p-nitrophenol
from p-nitrophenylpalmitate and free fatty acid from soybean
phospholipid). Means .+-. SE for n = 3 replications are shown.
PRODUCT pNPP p-nitrophenol free fatty acid Protein Species
(nmol/mg/min) (nmol/mg protein/min) Maltose-binding protein 0.71
.+-. 0.02 ND* Lipase fusion protein 12.01 .+-. 1.81 46.75 .+-. 1.24
*ND, not detectable
[0120] In other experiments, the enzymatic activity of the lipase
fusion protein was assayed by gas chromatography, a technique that
enables quantitation and identification of free fatty acids
released from the substrate. Trilinolein, soybean phospholipid and
dilinoleylphosphatidylcholine were used as substrates, and the
deesterified fatty acids were purified by thin layer chromatography
prior to being analyzed by gas chromatography. In keeping with the
spectrophotometric assay (Table 2), there was no detectable lipase
activity for maltose-binding protein alone with either soybean
phospholipid or dilinoleylphosphatidylcholine, indicating that
these substrates are essentially free of deesterified fatty acids
(Table 3). However, when the lipase fusion protein was used as a
source of enzyme, palmitic, stearic and linoleic acids were
deesterified from the soybean phospholipid extract, and linoleic
acid was deesterified from dilinoleylphosphatidylcholine (Table 3).
In contrast to the phospholipid substrates, detectable levels of
free linoleic acid were present in trilinolein, but the levels of
free linoleic acid were significantly increased in the presence of
lipase fusion protein indicating that the lipase is capable of
deesterifying fatty acids from triacylglycerol as well (Table 3).
TABLE-US-00003 TABLE 3 GC measurements of the lipolytic acyl
hydrolase activity of maltose-binding protein and lipase fusion
protein expressed in E. coli and purified by amylose column
chromatography Products (.mu.g/mg protein).sup.1 Maltose- Lipase
binding fusion Substrates Protein Protein Tri-linolein.sup.2
Linoleic acid (18:2) 15.9 .+-. 0.75 33.4 .+-. 1.58 Soybean Palmitic
acid (16:0) .sup. ND.sup.4 4.80 phospholipids.sup.3 Stearic acid
(18:0) ND 9.68 Linoleic acid (18:2) ND 5.80 Dilinoleylphos-
Linoleic acid (18:2) ND 20.0 phatydilcholine.sup.3 .sup.1Reaction
was allowed to proceed for 2 hours, and was not continuously linear
over this period. .sup.2Means .+-. SE for n = 3 replications are
shown .sup.3Single experiment .sup.4Not detectable
[0121] Lipase activity of the protein obtained by expression of the
lipase cDNA in E. coli was measured in vivo as described in Tsuboi,
et al., Infect. Immunol., 64:2936-2940 (1996); Wang, et al.,
Biotech., 9:741-746 (1995); and G. Sierra, J. Microbiol. and
Serol., 23:15-22 (1957). A single colony of E. coli BL-21 cells
transformed with pMal and another E. coli BL-21 colony transformed
with pMLip were inoculated in basal salt medium (pH 7.0) containing
(g/L): K.sub.2HPO.sub.4 (4.3), KH.sub.2PO.sub.4 (3.4),
(NH.sub.4)SO.sub.4 (2.0), MgCl.sub.2 (0.16), MnCl.sub.2.4H.sub.2O
(0.001), FeSO.sub.4.7H.sub.2O (0.0006), CaCl.sub.2.2H.sub.2O
(0.026), and NaMoO.sub.4.2H.sub.2O (0.002). Substrate, Tween 40
(polyoxyethylenesorbitan monopalmitate) or Tween 60
(polyoxyethylenesorbitan monostearate), was added at a
concentration of 1%. Growth of the bacterial cells at 37.degree. C.
with shaking was monitored by measuring the absorbance at 600 nm
(FIG. 5). As can be seen in FIG. 5, E. coli cells transformed with
pMLip were capable of growth in the Tween40/Tween60-supplemented
basal medium, after an initial lag period. However, E. coli cells
transformed with pMal did not grow in the Tween-supplemented
medium.
EXAMPLE 2
Ethylene Induction of Carnation Senescence-Induced Lipase Gene
[0122] Stage II carnation flowers and carnation cuttings were
treated with 0.5 ppm ethylene in a sealed chamber for 15 hours. RNA
was extracted from the ethylene treated Stage II flower petals and
from leaves of the treated cutting, as well as from the flower and
leaves of untreated carnation flowers and cuttings as described
below.
[0123] Arabidopsis plants were treated with 50 .mu.M ethephon in a
sealed chamber for one, two or three days. RNA was extracted from
the ethephon treated leaves of the plants as follows.
[0124] Flowers or leaves (1 flower or 5 g leaves) were ground in
liquid nitrogen. The ground powder was mixed with 30 ml guanidinium
buffer (4 M guanidinium isothiocyanate, 2.5 mM NaOAc pH 8.5, 0.8%
.beta.-mercaptoethanol). The mixture was filtered through four
layers of cheesecloth and centrifuged at 10,000 g at 4.degree. C.
for 30 minutes. The supernatant was then subjected to cesium
chloride density gradient centrifugation at 26,000 g for 20 hours.
The pelleted RNA was rinsed with 75% ethanol, resuspended in 600
.mu.l DEPC-treated water and the RNA precipitated at -70.degree. C.
with 0.75 ml 95% ethanol and 30 .mu.l of 3M NaOAc. Ten .mu.g of
either carnation or Arabidopsis RNA were fractionated on a 1.2%
denaturing formaldehyde agarose gel and transferred to a nylon
membrane. Randomly primed .sup.32P-dCTP-labelled full length
carnation lipase cDNA (SEQ ID NO:1) was used to probe the membrane
containing carnation RNA at 42.degree. C. overnight. Randomly
primed .sup.32P-dCTP-labelled full length Arabidopsis lipase cDNA
was used to probe the membrane containing Arabidopsis RNA at
42.degree. C. overnight. The membranes were then washed once in
1.times.SSC containing 0.1% SDS at room temperature for 15 minutes
and three times in 0.2.times.SSC containing 0.1% SDS at 65.degree.
C. for 15 minutes each. The membranes were exposed to x-ray film
overnight at -70.degree. C.
[0125] The results are shown in FIG. 9 (carnation) and FIG. 16
(Arabidopsis; lane 1, one day treatment; lane 2, two days
treatment; lane 3, three days treatment). As can be seen,
transcription of the carnation lipase and Arabidopsis lipase is
induced in flowers and/or leaves by ethylene.
EXAMPLE 3
Generation of Tomato PCR Product Using Carnation Lipase Primers
[0126] A partial length senescence-induced lipase sequence from
tomato genomic DNA obtained from tomato leaves was generated by
nested PCR using a pair of oligonucleotide primers designed from
carnation senescence-induced lipase sequence. The 5' primer is a
19-mer having the sequence, 5'-CTCTAGACTATGAGTGGGT (SEQ ID NO:7);
the 3' primer is an 18-mer having the sequence,
CGACTGGCACAACCTCCA-3' (SEQ ID NO:8). Polymerase chain reaction,
using genomic tomato DNA was carried out as follows:
[0127] Reaction Components: TABLE-US-00004 Genomic DNA 100 ng dNTP
(10 mM each) 1 .mu.l MgCl.sub.2 (5 mM) + 10.times. buffer 5 .mu.l
Primers 1 and 2 (20 .mu.M each) 0.5 .mu.l Taq DNA polymerase 1.25 U
Reaction volume 50 .mu.l
[0128] Reaction Parameters:
[0129] 94.degree. C. for 3 min
[0130] 94.degree. C./1 min, 48.degree. C./1 min, 72.degree. C./2
min, for 45 cycles
[0131] 72.degree. C. for 15 min.
[0132] The tomato partial length sequence obtained by PCR has the
nucleotide sequence, SEQ ID NO:6 (FIG. 10) and a deduced amino acid
sequence as set forth in FIG. 10. The partial length sequence
contains an intron (FIG. 10, lower case letters) interspersed
between two coding sequences. The tomato sequence contains the
conserved lipase consensus sequence, ITFTGHSLGA (SEQ ID NO:3).
[0133] The tomato sequence has 53.4% sequence identity with the
carnation senescence-induced lipase sequence and 43.5% sequence
identity with Arabidopsis lipase, the latter of which has 44.3%
sequence identity with the carnation sequence.
EXAMPLE 4
Effect of Chilling on Cell Membrane Integrity in Tomato Plants
[0134] Tomato plants were chilled for 48 hours at 7.degree. C. to
8.degree. C. and then returned to room temperature for 24 hours.
The effect of chilling on leaves was assessed by measuring the
amount of electrolyte leakage (.mu.Mhos).
[0135] Specifically, 1 g of leaf tissue was cut into a 50 ml tube,
quick-rinsed with distilled water, and 40 ml of deionized water
added. The tubes were capped and rotated at room temperature for 24
hours. Conductivity (.mu.Mho) readings reflecting electrolyte
leakage were taken at 6 and 24 hour intervals for control and
chill-injured leaf tissue. It is clear from FIG. 11 that
electrolyte leakage reflecting membrane damage is incurred during
the rewarming period in chill injured leaf tissue.
Northern Blot Analysis of RNA Obtained from Chilled Tomato
Leaves
[0136] Total RNA was isolated from the leaves 15 g of unchilled
tomato plants (control) and chilled tomato plants that had been
returned to room temperature for 0, 6 and 24 hours. RNA extraction
was carried out as described in Example 3. 10 .mu.g of RNA from
each sample was separated on a 1.2% denaturing formaldehyde gel and
transferred to a nylon membrane. The membrane was probed with
.sup.32P-dCTP-labelled probe (SEQ ID NO:3) and then washed under
the same conditions as described in Example 3. The results are
shown in FIG. 12.
[0137] As can be seen from the autoradiograph (FIG. 12B) tomato
lipase gene expression is induced by chilling and the pattern of
gene induction correlates with increased electrolyte leakage in
chill injured leaves (FIG. 11).
EXAMPLE 5
Generation of Transgenic Plants Expressing Senescence-Induced
Lipase Gene in Antisense Orientation
[0138] Agrobacteria were transformed with the binary vector,
pKYLX71, containing the full-length Arabidopsis senescence-induced
lipase gene expressed in antisense orientation under the regulation
of double 35S promoter. Arabidopsis plants were transformed with
these Agrobacteria by vacuum filtration, and transformed seeds from
the resultant T.sub.0 plants were selected on ampicillin.
[0139] T.sub.1 plants were grown under greenhouse conditions,
alongside wild-type Arabidopsis plants. Differences in leaf size,
overall plant size, seed yield and leaf senescence between
transgenic and wild-type plants were observed over time.
Differences are illustrated in FIGS. 17, 18, 19, and 20.
EXAMPLE 6
Reduced Senescence-Induced Lipase Production in Transgenic
Plants
[0140] Total protein isolated from leaves of four week-old
Arabidopsis wild-type and corresponding transgenic plants made as
in example 5 was transferred to a nylon membrane and probed with
antibody raised against the Arabidopsis senescence-induced lipase
protein. The Western blot is shown in FIG. 21. (Lanes 1 and 2 were
loaded with 9 .mu.g of protein, and lanes 3 and 4 were loaded with
18 .mu.g of protein). The expression of the senescence-induced
lipase was reduced in transgenic plants.
Sequence CWU 1
1
22 1 1537 DNA Dianthus caryophyllus CDS (48)..(1388) 1 gcacgagcca
ttccaaaact ccttacacca ctcaaaacta ttccaac atg gct gca 56 Met Ala Ala
1 gaa gcc caa cct tta ggc ctc tca aag ccc ggc cca aca tgg ccc gaa
104 Glu Ala Gln Pro Leu Gly Leu Ser Lys Pro Gly Pro Thr Trp Pro Glu
5 10 15 ctc ctc ggg tcc aac gct tgg gcc ggg cta cta aac ccg ctc aac
gat 152 Leu Leu Gly Ser Asn Ala Trp Ala Gly Leu Leu Asn Pro Leu Asn
Asp 20 25 30 35 gag ctc cgt gag ctc ctc cta cgc tgc ggg gac ttc tgc
cag gtg aca 200 Glu Leu Arg Glu Leu Leu Leu Arg Cys Gly Asp Phe Cys
Gln Val Thr 40 45 50 tac gac acc ttc ata aac gac cag aac tcg tcc
tac tgc ggc agc agc 248 Tyr Asp Thr Phe Ile Asn Asp Gln Asn Ser Ser
Tyr Cys Gly Ser Ser 55 60 65 cgc tac ggg aag gcg gac cta ctt cat
aag acc gcc ttc ccg ggg ggc 296 Arg Tyr Gly Lys Ala Asp Leu Leu His
Lys Thr Ala Phe Pro Gly Gly 70 75 80 gca gac cgg ttt gac gtg gtg
gcg tac ttg tac gcc act gcg aag gtc 344 Ala Asp Arg Phe Asp Val Val
Ala Tyr Leu Tyr Ala Thr Ala Lys Val 85 90 95 agc gtc cca gag gcg
ttt ctg ctg aag tcg agg tcg agg gag aag tgg 392 Ser Val Pro Glu Ala
Phe Leu Leu Lys Ser Arg Ser Arg Glu Lys Trp 100 105 110 115 gat agg
gaa tcg aat tgg att ggg tat gtc gtg gtg tcg aat gac gag 440 Asp Arg
Glu Ser Asn Trp Ile Gly Tyr Val Val Val Ser Asn Asp Glu 120 125 130
acg agt cgg gtg gcg gga cga agg gag gtg tat gtg gtg tgg aga ggg 488
Thr Ser Arg Val Ala Gly Arg Arg Glu Val Tyr Val Val Trp Arg Gly 135
140 145 act tgt agg gat tat gag tgg gtt gat gtt ctt ggt gct caa ctt
gag 536 Thr Cys Arg Asp Tyr Glu Trp Val Asp Val Leu Gly Ala Gln Leu
Glu 150 155 160 tct gct cat cct ttg tta cgc act caa caa act act cat
gtt gaa aag 584 Ser Ala His Pro Leu Leu Arg Thr Gln Gln Thr Thr His
Val Glu Lys 165 170 175 gtg gaa aat gag gaa aag aag agc att cat aaa
tca agt tgg tac gac 632 Val Glu Asn Glu Glu Lys Lys Ser Ile His Lys
Ser Ser Trp Tyr Asp 180 185 190 195 tgt ttc aat atc aac cta cta ggt
tcc gcg tcc aaa gac aaa gga aaa 680 Cys Phe Asn Ile Asn Leu Leu Gly
Ser Ala Ser Lys Asp Lys Gly Lys 200 205 210 gga agc gac gac gac gat
gat gac gac ccc aaa gtg atg caa ggt tgg 728 Gly Ser Asp Asp Asp Asp
Asp Asp Asp Pro Lys Val Met Gln Gly Trp 215 220 225 atg aca ata tac
aca tcg gag gat ccc aaa tca ccc ttc aca aaa cta 776 Met Thr Ile Tyr
Thr Ser Glu Asp Pro Lys Ser Pro Phe Thr Lys Leu 230 235 240 agt gca
aga aca caa ctt cag acc aaa ctc aaa caa cta atg aca aaa 824 Ser Ala
Arg Thr Gln Leu Gln Thr Lys Leu Lys Gln Leu Met Thr Lys 245 250 255
tac aaa gac gaa acc cta agc ata aca ttc gcc ggt cac agc cta ggc 872
Tyr Lys Asp Glu Thr Leu Ser Ile Thr Phe Ala Gly His Ser Leu Gly 260
265 270 275 gcg aca cta tca gtc gtg agc gcc ttc gac ata gtg gag aat
ctc acg 920 Ala Thr Leu Ser Val Val Ser Ala Phe Asp Ile Val Glu Asn
Leu Thr 280 285 290 acc gag atc cca gtc acg gcc gtg gtc ttc ggg tgc
cca aaa gta ggc 968 Thr Glu Ile Pro Val Thr Ala Val Val Phe Gly Cys
Pro Lys Val Gly 295 300 305 aac aaa aaa ttc caa caa ctc ttc gac tcg
tac cca aac cta aat gtc 1016 Asn Lys Lys Phe Gln Gln Leu Phe Asp
Ser Tyr Pro Asn Leu Asn Val 310 315 320 ctc cat gta agg aat gtc atc
gac ctg atc cct ctg tat ccc gtg aaa 1064 Leu His Val Arg Asn Val
Ile Asp Leu Ile Pro Leu Tyr Pro Val Lys 325 330 335 ctc atg ggt tac
gtg aac ata gga atc gag ctg gag atc gac tcg agg 1112 Leu Met Gly
Tyr Val Asn Ile Gly Ile Glu Leu Glu Ile Asp Ser Arg 340 345 350 355
aag tcg acc ttt cta aag gac tcg aaa aac ccg agt gat tgg cat aat
1160 Lys Ser Thr Phe Leu Lys Asp Ser Lys Asn Pro Ser Asp Trp His
Asn 360 365 370 ttg caa gca ata ttg cat gtt gta agt ggt tgg cat ggg
gtt aag ggg 1208 Leu Gln Ala Ile Leu His Val Val Ser Gly Trp His
Gly Val Lys Gly 375 380 385 gag ttt aag gtt gta aat aag aga agt gtt
gca ttg gtt aat aag tca 1256 Glu Phe Lys Val Val Asn Lys Arg Ser
Val Ala Leu Val Asn Lys Ser 390 395 400 tgt gat ttt ctt aag gaa gaa
tgt ttg gtt cct cca gct tgg tgg gtt 1304 Cys Asp Phe Leu Lys Glu
Glu Cys Leu Val Pro Pro Ala Trp Trp Val 405 410 415 gtg cag aac aaa
ggg atg gtt ttg aat aag gat ggt gag tgg gtt ttg 1352 Val Gln Asn
Lys Gly Met Val Leu Asn Lys Asp Gly Glu Trp Val Leu 420 425 430 435
gct cct cct gag gaa gat cct act cct gaa ttt gat tgataatatt 1398 Ala
Pro Pro Glu Glu Asp Pro Thr Pro Glu Phe Asp 440 445 tcatcatgtt
ttatattttt ataaatttta ctaaatttac atgacaattt atgggactaa 1458
gttacttatt tatatgttta ttatatttga aatgtgtttt aagttacata aaattgcaat
1518 tagttttaaa aaaaaaaaa 1537 2 447 PRT Dianthus caryophyllus 2
Met Ala Ala Glu Ala Gln Pro Leu Gly Leu Ser Lys Pro Gly Pro Thr 1 5
10 15 Trp Pro Glu Leu Leu Gly Ser Asn Ala Trp Ala Gly Leu Leu Asn
Pro 20 25 30 Leu Asn Asp Glu Leu Arg Glu Leu Leu Leu Arg Cys Gly
Asp Phe Cys 35 40 45 Gln Val Thr Tyr Asp Thr Phe Ile Asn Asp Gln
Asn Ser Ser Tyr Cys 50 55 60 Gly Ser Ser Arg Tyr Glu Lys Ala Asp
Leu Leu His Lys Thr Ala Phe 65 70 75 80 Pro Gly Gly Ala Asp Arg Phe
Asp Val Val Ala Tyr Leu Tyr Ala Thr 85 90 95 Ala Lys Val Ser Val
Pro Glu Ala Phe Leu Leu Lys Ser Arg Ser Arg 100 105 110 Glu Lys Trp
Asp Arg Glu Ser Asn Trp Ile Gly Tyr Val Val Val Ser 115 120 125 Asn
Asp Glu Thr Ser Arg Val Ala Gly Arg Arg Glu Val Tyr Val Val 130 135
140 Trp Arg Gly Thr Cys Arg Asp Tyr Glu Trp Val Asp Val Leu Gly Ala
145 150 155 160 Gln Leu Glu Ser Ala His Pro Leu Leu Arg Thr Gln Gln
Thr Thr His 165 170 175 Val Glu Lys Val Glu Asn Glu Glu Lys Lys Ser
Ile His Lys Ser Ser 180 185 190 Trp Tyr Asp Cys Phe Asn Ile Asn Leu
Leu Gly Ser Ala Ser Lys Asp 195 200 205 Lys Gly Lys Gly Ser Asp Asp
Asp Asp Asp Asp Asp Pro Lys Val Met 210 215 220 Gln Gly Trp Met Thr
Ile Tyr Thr Ser Glu Asp Pro Lys Ser Pro Phe 225 230 235 240 Thr Lys
Leu Ser Ala Arg Thr Gln Leu Gln Thr Lys Leu Lys Gln Leu 245 250 255
Met Thr Lys Tyr Lys Asp Glu Thr Leu Ser Ile Thr Phe Ala Gly His 260
265 270 Ser Leu Gly Ala Thr Leu Ser Val Val Ser Ala Phe Asp Ile Val
Glu 275 280 285 Asn Leu Thr Thr Glu Ile Pro Val Thr Ala Val Val Phe
Gly Cys Pro 290 295 300 Lys Val Gly Asn Lys Lys Phe Gln Gln Leu Phe
Asp Ser Tyr Pro Asn 305 310 315 320 Leu Asn Val Leu His Val Arg Asn
Val Ile Asp Leu Ile Pro Leu Tyr 325 330 335 Pro Val Lys Leu Met Gly
Tyr Val Asn Ile Gly Ile Glu Leu Glu Ile 340 345 350 Asp Ser Arg Lys
Ser Thr Phe Leu Lys Asp Ser Lys Asn Pro Ser Asp 355 360 365 Trp His
Asn Leu Gln Ala Ile Leu His Val Val Ser Gly Trp His Gly 370 375 380
Val Lys Gly Glu Phe Lys Val Val Asn Lys Arg Ser Val Ala Leu Val 385
390 395 400 Asn Lys Ser Cys Asp Phe Leu Lys Glu Glu Cys Leu Val Pro
Pro Ala 405 410 415 Trp Trp Val Val Gln Asn Lys Gly Met Val Leu Asn
Lys Asp Gly Glu 420 425 430 Trp Val Leu Ala Pro Pro Glu Glu Asp Pro
Thr Pro Glu Phe Asp 435 440 445 3 10 PRT Lycopersicon esculentum 3
Ile Thr Phe Thr Gly His Ser Leu Gly Ala 1 5 10 4 10 PRT Dianthus
caryophyllus 4 Ile Thr Phe Ala Gly His Ser Leu Gly Ala 1 5 10 5 19
DNA Dianthus caryophyllus 5 acctactagg ttccgcgtc 19 6 923 DNA
Lycopersicon esculentum CDS (6)...(513) CDS (845)...(921) 6 ctcta
gac tat gag tgg gtg gat gtt tta ggt gct cgt cct gat tca 47 Asp Tyr
Glu Trp Val Asp Val Leu Gly Ala Arg Pro Asp Ser 1 5 10 gct gac tct
ctt ctt cat cct aaa tct ctc caa aaa ggc att aac aac 95 Ala Asp Ser
Leu Leu His Pro Lys Ser Leu Gln Lys Gly Ile Asn Asn 15 20 25 30 aag
aac gat gag gat gag gac gag gac gag gat gag atc aaa gta atg 143 Lys
Asn Asp Glu Asp Glu Asp Glu Asp Glu Asp Glu Ile Lys Val Met 35 40
45 gat ggg tgg ctt aag atc tac gtc tca agt aac ccg aag tcg tct ttc
191 Asp Gly Trp Leu Lys Ile Tyr Val Ser Ser Asn Pro Lys Ser Ser Phe
50 55 60 acg aga cta agt gca aga gaa caa ctt caa gca aag att gaa
aag tta 239 Thr Arg Leu Ser Ala Arg Glu Gln Leu Gln Ala Lys Ile Glu
Lys Leu 65 70 75 aga aat gag tat aaa gat gag aat ttg agc ata act
ttt aca ggg cat 287 Arg Asn Glu Tyr Lys Asp Glu Asn Leu Ser Ile Thr
Phe Thr Gly His 80 85 90 agt ctt ggt gct agc tta gct gtt tta gct
tca ttt gat gtg gtt gaa 335 Ser Leu Gly Ala Ser Leu Ala Val Leu Ala
Ser Phe Asp Val Val Glu 95 100 105 110 aat ggt gtg cca gtt gat att
cca gta tct gca att gta ttt ggt agt 383 Asn Gly Val Pro Val Asp Ile
Pro Val Ser Ala Ile Val Phe Gly Ser 115 120 125 cca caa gtt ggg aat
aag gca ttc aat gaa aga atc aag aaa ttc tca 431 Pro Gln Val Gly Asn
Lys Ala Phe Asn Glu Arg Ile Lys Lys Phe Ser 130 135 140 aac ttg aat
atc tta cat gtt aag aac aag att gat ctc att acc ctt 479 Asn Leu Asn
Ile Leu His Val Lys Asn Lys Ile Asp Leu Ile Thr Leu 145 150 155 tac
cca agt gct ctg ttt ggg tat gtg aat tca g gtattgaagg 523 Tyr Pro
Ser Ala Leu Phe Gly Tyr Val Asn Ser 160 165 aaaagatcat tacaattttg
agctagattt ctcatatcgt cacactcaac taacagttat 583 tatatgagaa
agtcactttc tttgtgaaaa aattgaatca acttttggaa ataatagtag 643
ttgagtgacc atatgagaaa tcaacactct actaacttta tgctataaga gaataggtta
703 aggtccatat gtttatactg tctgttcaat tagaatcata aaagtattac
tagttaaatt 763 tgactacaat cttatgtaga catgaataaa ataaatccta
cataaataag atttcctaca 823 actttaatga ttcttcaaca g gt ata gag cta
gtc atc gat agc aga aag 873 Gly Ile Glu Leu Val Ile Asp Ser Arg Lys
170 175 tct ccg agt tta aag gat tca aaa gac atg ggc gac tgg cac aac
ctc 921 Ser Pro Ser Leu Lys Asp Ser Lys Asp Met Gly Asp Trp His Asn
Leu 180 185 190 195 ca 923 7 19 DNA Artificial Sequence Description
of Artificial Sequence Synthetic Primer 7 ctctagacta tgagtgggt 19 8
18 DNA Artificial Sequence Description of Artificial Sequence
Synthetic Primer 8 cgactggcac aacctcca 18 9 10 PRT Arabidopsis sp.
9 Ile Thr Thr Cys Gly His Ser Leu Gly Ala 1 5 10 10 10 PRT Ipomoea
nil 10 Ile Thr Val Thr Gly His Ser Leu Gly Ser 1 5 10 11 447 PRT
Dianthus caryophyllus 11 Met Ala Ala Glu Ala Gln Pro Leu Gly Leu
Ser Lys Pro Gly Pro Thr 1 5 10 15 Trp Pro Glu Leu Leu Gly Ser Asn
Ala Trp Ala Gly Leu Leu Asn Pro 20 25 30 Leu Asn Asp Glu Leu Arg
Glu Leu Leu Leu Arg Cys Gly Asp Phe Cys 35 40 45 Gln Val Thr Tyr
Asp Thr Phe Ile Asn Asp Gln Asn Ser Ser Tyr Cys 50 55 60 Gly Ser
Ser Arg Tyr Gly Lys Ala Asp Leu Leu His Lys Thr Ala Phe 65 70 75 80
Pro Gly Gly Ala Asp Arg Phe Asp Val Val Ala Tyr Leu Tyr Ala Thr 85
90 95 Ala Lys Val Ser Val Pro Glu Ala Phe Leu Leu Lys Ser Arg Ser
Arg 100 105 110 Glu Lys Trp Asp Arg Glu Ser Asn Trp Ile Gly Tyr Val
Val Val Ser 115 120 125 Asn Asp Glu Thr Ser Arg Val Ala Gly Arg Arg
Glu Val Tyr Val Val 130 135 140 Trp Arg Gly Thr Cys Arg Asp Tyr Glu
Trp Val Asp Val Leu Gly Ala 145 150 155 160 Gln Leu Glu Ser Ala His
Pro Leu Leu Arg Thr Gln Gln Thr Thr His 165 170 175 Val Glu Lys Val
Glu Asn Glu Glu Lys Lys Ser Ile His Lys Ser Ser 180 185 190 Trp Tyr
Asp Cys Phe Asn Ile Asn Leu Leu Gly Ser Ala Ser Lys Asp 195 200 205
Lys Gly Lys Gly Ser Asp Asp Asp Asp Asp Asp Asp Pro Lys Val Met 210
215 220 Gln Gly Trp Met Thr Ile Tyr Thr Ser Glu Asp Pro Lys Ser Pro
Phe 225 230 235 240 Thr Lys Leu Ser Ala Arg Thr Gln Leu Gln Thr Lys
Leu Lys Cys Leu 245 250 255 Met Thr Lys Tyr Lys Asp Glu Thr Leu Ser
Ile Thr Phe Ala Gly His 260 265 270 Ser Leu Gly Ala Thr Leu Ser Val
Val Ser Ala Phe Asp Ile Val Glu 275 280 285 Asn Leu Thr Thr Glu Ile
Pro Val Thr Ala Val Val Phe Gly Cys Pro 290 295 300 Lys Val Gly Asn
Lys Lys Phe Gln Gln Leu Phe Asp Ser Tyr Pro Asn 305 310 315 320 Leu
Asn Val Leu His Val Arg Asn Val Ile Asp Leu Ile Pro Leu Tyr 325 330
335 Pro Val Lys Leu Met Gly Tyr Val Asn Ile Gly Ile Glu Leu Glu Ile
340 345 350 Asp Ser Arg Lys Ser Thr Phe Leu Lys Asp Ser Lys Asn Pro
Ser Asp 355 360 365 Trp His Asn Leu Gln Ala Ile Leu His Val Val Ser
Gly Trp His Gly 370 375 380 Val Lys Gly Glu Phe Lys Val Val Asn Lys
Arg Ser Val Ala Leu Val 385 390 395 400 Asn Lys Ser Cys Asp Phe Leu
Lys Glu Glu Cys Leu Val Pro Pro Ala 405 410 415 Trp Trp Val Val Gln
Asn Lys Gly Met Val Leu Asn Lys Asp Gly Glu 420 425 430 Trp Val Leu
Ala Pro Pro Glu Glu Asp Pro Thr Pro Glu Phe Asp 435 440 445 12 418
PRT Arabidopsis thaliana 12 Met Lys Arg Lys Lys Lys Glu Glu Glu Glu
Glu Lys Leu Ile Val Thr 1 5 10 15 Arg Glu Phe Ala Lys Arg Trp Arg
Asp Leu Ser Gly Gln Asn His Trp 20 25 30 Lys Gly Met Leu Gln Pro
Leu Asp Gln Asp Leu Arg Glu Tyr Ile Ile 35 40 45 His Tyr Gly Glu
Met Ala Gln Ala Gly Tyr Asp Thr Phe Asn Ile Asn 50 55 60 Thr Glu
Ser Gln Phe Ala Gly Ala Ser Ile Tyr Ser Arg Lys Asp Phe 65 70 75 80
Phe Ala Lys Val Gly Leu Glu Ile Ala His Pro Tyr Thr Lys Tyr Lys 85
90 95 Val Thr Lys Phe Ile Tyr Ala Thr Ser Asp Ile His Val Pro Glu
Ser 100 105 110 Phe Leu Leu Phe Pro Ile Ser Arg Glu Gly Trp Ser Lys
Glu Ser Asn 115 120 125 Trp Met Gly Tyr Val Ala Val Thr Asp Asp Gln
Gly Thr Ala Leu Leu 130 135 140 Gly Arg Arg Asp Ile Val Val Ser Trp
Arg Gly Ser Val Gln Pro Leu 145 150 155 160 Glu Trp Val Glu Asp Phe
Glu Phe Gly Leu Val Asn Ala Ile Lys Ile 165 170 175 Phe Gly Glu Arg
Asn Asp Gln Val Gln Ile His Gln Gly Trp Tyr Ser 180 185 190 Ile Tyr
Met Ser Gln Asp Glu Arg Ser Pro Phe Thr Lys Thr Asn Ala 195 200 205
Arg Asp Gln Val Leu Arg Glu Val Gly Arg Leu Leu Glu Lys Tyr Lys 210
215 220 Asp Glu Glu Val Ser Ile Thr Ile Cys Gly His Ser Leu Gly Ala
Ala 225 230 235 240 Leu Ala Thr Asp Ser Ala Ile Asp Ile Val Ala
Asn
Gly Tyr Asn Arg 245 250 255 Pro Lys Ser Arg Pro Asp Lys Ser Cys Pro
Val Thr Ala Phe Val Phe 260 265 270 Ala Ser Pro Arg Val Gly Asp Ser
Asp Phe Arg Lys Leu Phe Ser Gly 275 280 285 Leu Glu Asp Ile Arg Val
Leu Arg Thr Arg Asn Leu Phe Asp Val Ile 290 295 300 Pro Ile Tyr Pro
Pro Ile Gly Tyr Ser Glu Val Gly Asp Glu Phe Pro 305 310 315 320 Ile
Asp Thr Arg Lys Ser Pro Tyr Met Lys Ser Pro Gly Asn Leu Ala 325 330
335 Thr Phe His Cys Leu Glu Gly Tyr Leu His Gly Val Ala Gly Thr Gln
340 345 350 Gly Thr Asn Lys Ala Asp Leu Phe Arg Leu Asp Val Glu Arg
Ala Ile 355 360 365 Gly Leu Val Asn Lys Ser Val Asp Gly Leu Lys Asp
Glu Cys Met Val 370 375 380 Pro Gly Lys Trp Arg Val Leu Lys Asn Lys
Gly Ala Gln Gln Asp Asp 385 390 395 400 Gly Ser Trp Glu Leu Val Asp
His Glu Ile Asp Asp Asn Glu Asp Leu 405 410 415 Asp Phe 13 401 PRT
Ipomoea sp. 13 Met Ser Gly Ile Ala Lys Arg Trp Lys Val Leu Ser Gly
Ser Asp Asn 1 5 10 15 Trp Glu Gly Leu Leu Glu Pro Leu Asp Ser Asp
Leu Arg Arg Tyr Leu 20 25 30 Ile His Tyr Gly Thr Met Val Ser Pro
Ala Thr Asp Ser Phe Ile Asn 35 40 45 Glu Ala Ala Ser Lys Asn Val
Gly Leu Pro Arg Tyr Ala Arg Arg Asn 50 55 60 Leu Leu Ala Asn Cys
Gly Leu Val Lys Gly Asn Pro Phe Lys Tyr Glu 65 70 75 80 Val Thr Lys
Tyr Phe Tyr Ala Pro Ser Thr Ile Pro Leu Pro Asp Glu 85 90 95 Gly
Tyr Asn Val Arg Ala Thr Arg Ala Asp Ala Val Leu Lys Glu Ser 100 105
110 Asn Trp Asn Gly Tyr Val Ala Val Ala Thr Asp Glu Gly Lys Val Ala
115 120 125 Leu Gly Arg Arg Asp Ile Leu Ile Val Trp Arg Gly Thr Ile
Arg Lys 130 135 140 Ser Glu Trp Asn Glu Asn Leu Thr Phe Trp Phe Val
Lys Ala Pro Leu 145 150 155 160 Phe Phe Gly Gln Asn Ser Asp Pro Leu
Val His Lys Gly Trp Tyr Asp 165 170 175 Met Tyr Thr Thr Ile Asn Gln
Asp Ser Gln Leu Asn Glu Lys Ser Ala 180 185 190 Arg Asp Gln Ile Arg
Glu Glu Val Ala Arg Leu Val Glu Leu Tyr Lys 195 200 205 Asp Glu Asp
Ile Ser Ile Thr Val Thr Gly His Ser Leu Gly Ser Ser 210 215 220 Met
Ala Thr Leu Asn Ala Val Asp Leu Ala Ala Asn Pro Ile Asn Asn 225 230
235 240 Asn Lys Asn Ile Leu Val Thr Ala Phe Leu Tyr Ala Ser Pro Lys
Val 245 250 255 Gly Asp Glu Asn Phe Lys Asn Val Ile Ser Asn Gln Gln
Asn Leu Arg 260 265 270 Ala Leu Arg Ile Ser Asp Val Asn Asp Ile Val
Thr Ala Val Pro Pro 275 280 285 Phe Gly Trp Lys Glu Cys Asp Asn Thr
Ala Ile Leu Tyr Gly Asp Val 290 295 300 Gly Val Gly Leu Val Ile Asp
Ser Lys Lys Ser His Tyr Leu Lys Pro 305 310 315 320 Asp Phe Pro Asn
Leu Ser Thr His Asp Leu Met Leu Tyr Met His Ala 325 330 335 Ile Asp
Gly Tyr Gln Gly Ser Gln Gly Gly Phe Glu Arg Gln Glu Asp 340 345 350
Phe Asp Leu Ala Lys Val Asn Lys Tyr Gly Asp Tyr Leu Lys Ala Glu 355
360 365 Tyr Pro Ile Pro Ile Gly Trp Phe Asn Ile Lys Asp Lys Gly Met
Gln 370 375 380 Gln Asp Asp Gly Asn Tyr Ile Leu Asp Asp His Glu Val
Asp Lys Thr 385 390 395 400 Phe 14 448 PRT Arabidopsis thaliana 14
Met Thr Ala Glu Asp Ile Arg Arg Arg Asp Lys Lys Thr Glu Glu Glu 1 5
10 15 Arg Arg Leu Arg Asp Thr Trp Arg Lys Ile Gln Gly Glu Asp Asp
Trp 20 25 30 Ala Gly Leu Met Asp Pro Met Asp Pro Ile Leu Arg Ser
Glu Leu Ile 35 40 45 Arg Tyr Gly Glu Met Ala Gln Ala Cys Tyr Asp
Ala Phe Asp Phe Asp 50 55 60 Pro Ala Ser Lys Tyr Cys Gly Thr Ser
Arg Phe Thr Arg Leu Glu Phe 65 70 75 80 Phe Asp Ser Leu Gly Met Ile
Asp Ser Gly Tyr Glu Val Ala Arg Tyr 85 90 95 Leu Tyr Ala Thr Ser
Asn Ile Asn Leu Pro Asn Phe Phe Ser Lys Ser 100 105 110 Arg Trp Ser
Lys Val Trp Ser Lys Asn Ala Asn Trp Met Gly Tyr Val 115 120 125 Ala
Val Ser Asp Asp Glu Thr Ser Arg Asn Arg Leu Gly Arg Arg Asp 130 135
140 Ile Ala Ile Ala Trp Arg Gly Thr Val Thr Lys Leu Glu Trp Ile Ala
145 150 155 160 Asp Leu Lys Asp Tyr Leu Lys Pro Val Thr Glu Asn Lys
Ile Arg Cys 165 170 175 Pro Asp Pro Ala Val Lys Val Glu Ser Gly Phe
Leu Asp Leu Tyr Thr 180 185 190 Asp Lys Asp Thr Thr Cys Lys Phe Ala
Arg Phe Ser Ala Arg Glu Gln 195 200 205 Ile Leu Thr Glu Val Lys Arg
Leu Val Glu Glu His Gly Asp Asp Asp 210 215 220 Asp Ser Asp Leu Ser
Ile Thr Val Thr Gly His Ser Leu Gly Gly Ala 225 230 235 240 Leu Ala
Ile Leu Ser Ala Tyr Asp Ile Ala Glu Met Arg Leu Asn Arg 245 250 255
Ser Lys Lys Gly Lys Val Ile Pro Val Thr Ala Val Leu Thr Tyr Gly 260
265 270 Gly Pro Arg Val Gly Asn Val Arg Phe Arg Glu Arg Met Glu Glu
Leu 275 280 285 Gly Val Lys Val Met Arg Val Val Asn Val His Asp Val
Val Pro Lys 290 295 300 Ser Pro Gly Leu Phe Leu Asn Glu Ser Arg Pro
His Ala Leu Met Lys 305 310 315 320 Ile Ala Glu Gly Leu Pro Trp Cys
Tyr Ser His Val Gly Glu Glu Leu 325 330 335 Ala Leu Asp His Gln Asn
Ser Pro Phe Leu Lys Pro Ser Val Asp Val 340 345 350 Ser Thr Ala His
Asn Leu Glu Ala Met Leu His Leu Leu Asp Gly Tyr 355 360 365 His Gly
Lys Gly Glu Arg Phe Val Leu Ser Ser Gly Arg Asp His Ala 370 375 380
Leu Val Asn Lys Ala Ser Asp Phe Leu Lys Glu His Leu Gln Ile Pro 385
390 395 400 Pro Phe Trp Arg Gln Asp Ala Asn Lys Gly Met Val Arg Asn
Ser Glu 405 410 415 Gly Arg Trp Ile Gln Ala Glu Arg Leu Arg Phe Glu
Asp His His Ser 420 425 430 Pro Asp Ile His His His Leu Ser Gln Leu
Arg Leu Asp His Pro Cys 435 440 445 15 1167 DNA Arabidopsis sp. CDS
(1)..(1044) 15 cgg gtc gac cca cgc gtc cgc gaa aac gct tcc gac tac
gag gtt gta 48 Arg Val Asp Pro Arg Val Arg Glu Asn Ala Ser Asp Tyr
Glu Val Val 1 5 10 15 aac ttc ctc tac gcc aca gct cgt gtt tct ctc
ccc gaa ggt ttg ctt 96 Asn Phe Leu Tyr Ala Thr Ala Arg Val Ser Leu
Pro Glu Gly Leu Leu 20 25 30 ctc caa tca caa tca aga gat tct tgg
gac cgt gag tct aac tgg ttt 144 Leu Gln Ser Gln Ser Arg Asp Ser Trp
Asp Arg Glu Ser Asn Trp Phe 35 40 45 ggc tac att gct gtc acg tct
gat gaa cgg tct aag gct tta gga cgc 192 Gly Tyr Ile Ala Val Thr Ser
Asp Glu Arg Ser Lys Ala Leu Gly Arg 50 55 60 cgt gag atc tat ata
gct ttg aga gga acg agc agg aac tat gag tgg 240 Arg Glu Ile Tyr Ile
Ala Leu Arg Gly Thr Ser Arg Asn Tyr Glu Trp 65 70 75 80 gtc aat gtt
ttg ggt gct agg cca act tca gct gac ccc ttg ctg cac 288 Val Asn Val
Leu Gly Ala Arg Pro Thr Ser Ala Asp Pro Leu Leu His 85 90 95 gga
ccc gag cag gat ggt tct ggt ggt gta gtt gaa ggt acg act ttt 336 Gly
Pro Glu Gln Asp Gly Ser Gly Gly Val Val Glu Gly Thr Thr Phe 100 105
110 gat agt gac agt gaa gat gaa gaa ggg tgt aag gtg atg ctc ggg tgg
384 Asp Ser Asp Ser Glu Asp Glu Glu Gly Cys Lys Val Met Leu Gly Trp
115 120 125 ctc aca atc tat act tct aat cac ccc gaa tcg aaa ttc act
aag ctg 432 Leu Thr Ile Tyr Thr Ser Asn His Pro Glu Ser Lys Phe Thr
Lys Leu 130 135 140 agt cta cgg tca cag ttg tta gcc aag atc aag gag
ctt ctg ttg aag 480 Ser Leu Arg Ser Gln Leu Leu Ala Lys Ile Lys Glu
Leu Leu Leu Lys 145 150 155 160 tat aag gac gag aaa ccg agc att gtg
ttg act gga cat agc ttg gga 528 Tyr Lys Asp Glu Lys Pro Ser Ile Val
Leu Thr Gly His Ser Leu Gly 165 170 175 cct aca gag gct gtt ctg gcc
gcc tat gat ata gct gag aac ggt tcc 576 Pro Thr Glu Ala Val Leu Ala
Ala Tyr Asp Ile Ala Glu Asn Gly Ser 180 185 190 agt gat gat gtt ccg
gtc act gct ata gtc ttt ggt tgt cca cag gta 624 Ser Asp Asp Val Pro
Val Thr Ala Ile Val Phe Gly Cys Pro Gln Val 195 200 205 gga aac aag
gag ttc aga gac gaa gta atg agt cac aag aac tta aag 672 Gly Asn Lys
Glu Phe Arg Asp Glu Val Met Ser His Lys Asn Leu Lys 210 215 220 atc
ctc cat gta agg aac acg att gat ctc tta act cga tac cca ggg 720 Ile
Leu His Val Arg Asn Thr Ile Asp Leu Leu Thr Arg Tyr Pro Gly 225 230
235 240 gga ctt tta ggg tat gtg gac ata gga ata aac ttt gtg atc gat
aca 768 Gly Leu Leu Gly Tyr Val Asp Ile Gly Ile Asn Phe Val Ile Asp
Thr 245 250 255 aag aag tca ccg ttc cta agc gat tca agg aat cca ggg
gat tgg cat 816 Lys Lys Ser Pro Phe Leu Ser Asp Ser Arg Asn Pro Gly
Asp Trp His 260 265 270 aat ctt cag gcg atg tta cat gtt gta gct gga
tgg aat ggg aag aaa 864 Asn Leu Gln Ala Met Leu His Val Val Ala Gly
Trp Asn Gly Lys Lys 275 280 285 gga gag ttt aaa ctg atg gtt aag aga
agt att gca tta gtg aac aag 912 Gly Glu Phe Lys Leu Met Val Lys Arg
Ser Ile Ala Leu Val Asn Lys 290 295 300 tca tgc gag ttc ttg aaa gct
gag tgt ttg gtg cca gga tct tgg tgg 960 Ser Cys Glu Phe Leu Lys Ala
Glu Cys Leu Val Pro Gly Ser Trp Trp 305 310 315 320 gta gag aag aac
aaa gga ctg atc aag aac gaa gat ggt gaa tgg gtt 1008 Val Glu Lys
Asn Lys Gly Leu Ile Lys Asn Glu Asp Gly Glu Trp Val 325 330 335 ctt
gct ccc gtt gaa gaa gaa cct gta cct gaa ttc taaattgtat 1054 Leu Ala
Pro Val Glu Glu Glu Pro Val Pro Glu Phe 340 345 ttctgtattt
ttctctaagg tcatgataaa tcaacaataa gcagttcaac tatgtgatga 1114
aaagacccaa gttattatat tgatatgagt ttatgagata aaaaaaaaaa aaa 1167 16
348 PRT Arabidopsis sp. 16 Arg Val Asp Pro Arg Val Arg Glu Asn Ala
Ser Asp Tyr Glu Val Val 1 5 10 15 Asn Phe Leu Tyr Ala Thr Ala Arg
Val Ser Leu Pro Glu Gly Leu Leu 20 25 30 Leu Gln Ser Gln Ser Arg
Asp Ser Trp Asp Arg Glu Ser Asn Trp Phe 35 40 45 Gly Tyr Ile Ala
Val Thr Ser Asp Glu Arg Ser Lys Ala Leu Gly Arg 50 55 60 Arg Glu
Ile Tyr Ile Ala Leu Arg Gly Thr Ser Arg Asn Tyr Glu Trp 65 70 75 80
Val Asn Val Leu Gly Ala Arg Pro Thr Ser Ala Asp Pro Leu Leu His 85
90 95 Gly Pro Glu Gln Asp Gly Ser Gly Gly Val Val Glu Gly Thr Thr
Phe 100 105 110 Asp Ser Asp Ser Glu Asp Glu Glu Gly Cys Lys Val Met
Leu Gly Trp 115 120 125 Leu Thr Ile Tyr Thr Ser Asn His Pro Glu Ser
Lys Phe Thr Lys Leu 130 135 140 Ser Leu Arg Ser Gln Leu Leu Ala Lys
Ile Lys Glu Leu Leu Leu Lys 145 150 155 160 Tyr Lys Asp Glu Lys Pro
Ser Ile Val Leu Thr Gly His Ser Leu Gly 165 170 175 Pro Thr Glu Ala
Val Leu Ala Ala Tyr Asp Ile Ala Glu Asn Gly Ser 180 185 190 Ser Asp
Asp Val Pro Val Thr Ala Ile Val Phe Gly Cys Pro Gln Val 195 200 205
Gly Asn Lys Glu Phe Arg Asp Glu Val Met Ser His Lys Asn Leu Lys 210
215 220 Ile Leu His Val Arg Asn Thr Ile Asp Leu Leu Thr Arg Tyr Pro
Gly 225 230 235 240 Gly Leu Leu Gly Tyr Val Asp Ile Gly Ile Asn Phe
Val Ile Asp Thr 245 250 255 Lys Lys Ser Pro Phe Leu Ser Asp Ser Arg
Asn Pro Gly Asp Trp His 260 265 270 Asn Leu Gln Ala Met Leu His Val
Val Ala Gly Trp Asn Gly Lys Lys 275 280 285 Gly Glu Phe Lys Leu Met
Val Lys Arg Ser Ile Ala Leu Val Asn Lys 290 295 300 Ser Cys Glu Phe
Leu Lys Ala Glu Cys Leu Val Pro Gly Ser Trp Trp 305 310 315 320 Val
Glu Lys Asn Lys Gly Leu Ile Lys Asn Glu Asp Gly Glu Trp Val 325 330
335 Leu Ala Pro Val Glu Glu Glu Pro Val Pro Glu Phe 340 345 17 195
PRT Lycopersicon esculentum 17 Asp Tyr Glu Trp Val Asp Val Leu Gly
Ala Arg Pro Asp Ser Ala Asp 1 5 10 15 Ser Leu Leu His Pro Lys Ser
Leu Gln Lys Gly Ile Asn Asn Lys Asn 20 25 30 Asp Glu Asp Glu Asp
Glu Asp Glu Asp Glu Ile Lys Val Met Asp Gly 35 40 45 Trp Leu Lys
Ile Tyr Val Ser Ser Asn Pro Lys Ser Ser Phe Thr Arg 50 55 60 Leu
Ser Ala Arg Glu Gln Leu Gln Ala Lys Ile Glu Lys Leu Arg Asn 65 70
75 80 Glu Tyr Lys Asp Glu Asn Leu Ser Ile Thr Phe Thr Gly His Ser
Leu 85 90 95 Gly Ala Ser Leu Ala Val Leu Ala Ser Phe Asp Val Val
Glu Asn Gly 100 105 110 Val Pro Val Asp Ile Pro Val Ser Ala Ile Val
Phe Gly Ser Pro Gln 115 120 125 Val Gly Asn Lys Ala Phe Asn Glu Arg
Ile Lys Lys Phe Ser Asn Leu 130 135 140 Asn Ile Leu His Val Lys Asn
Lys Ile Asp Leu Ile Thr Leu Tyr Pro 145 150 155 160 Ser Ala Leu Phe
Gly Tyr Val Asn Ser Gly Ile Glu Leu Val Ile Asp 165 170 175 Ser Arg
Lys Ser Pro Ser Leu Lys Asp Ser Lys Asp Met Gly Asp Trp 180 185 190
His Asn Leu 195 18 1344 DNA Arabidopsis thaliana CDS (1)..(1341) 18
atg acg gcg gaa gat att cgc cgg cga gat aaa aaa acc gaa gaa gaa 48
Met Thr Ala Glu Asp Ile Arg Arg Arg Asp Lys Lys Thr Glu Glu Glu 1 5
10 15 aga aga cta aga gac acg tgg cgt aag atc caa gga gaa gac gat
tgg 96 Arg Arg Leu Arg Asp Thr Trp Arg Lys Ile Gln Gly Glu Asp Asp
Trp 20 25 30 gcc ggg tta atg gat cca atg gat cca att ctt aga tcg
gag cta atc 144 Ala Gly Leu Met Asp Pro Met Asp Pro Ile Leu Arg Ser
Glu Leu Ile 35 40 45 cgt tac ggc gaa atg gct caa gct tgt tac gac
gct ttc gat ttc gat 192 Arg Tyr Gly Glu Met Ala Gln Ala Cys Tyr Asp
Ala Phe Asp Phe Asp 50 55 60 ccc gct tcc aaa tac tgc ggc acc tcc
agg ttc acg cga ctc gag ttc 240 Pro Ala Ser Lys Tyr Cys Gly Thr Ser
Arg Phe Thr Arg Leu Glu Phe 65 70 75 80 ttc gat tct ctc gga atg atc
gat tcc ggt tac gag gtg gcg cgt tac 288 Phe Asp Ser Leu Gly Met Ile
Asp Ser Gly Tyr Glu Val Ala Arg Tyr 85 90 95 ctc tac gcg acg tcg
aac atc aat ctc ccg aac ttc ttc tcg aaa tcg 336 Leu Tyr Ala Thr Ser
Asn Ile Asn Leu Pro Asn Phe Phe Ser Lys Ser 100 105 110 cgg tgg tct
aaa gtc tgg agc aaa aac gct aat tgg atg gga tac gtc 384 Arg Trp Ser
Lys Val Trp Ser Lys Asn Ala Asn Trp Met Gly Tyr Val 115 120 125 gcc
gtt tca gac gac gaa acg tct cgt aac cga ctc ggc cgc cgt gat 432 Ala
Val Ser Asp Asp Glu Thr Ser Arg Asn Arg Leu Gly Arg Arg Asp 130 135
140 atc gcg att gcg tgg aga gga acc gtt acg aaa ctt gaa tgg atc gcg
480 Ile Ala Ile Ala Trp Arg Gly Thr Val Thr Lys Leu Glu Trp Ile Ala
145 150 155 160 gat cta aag gat tat tta aaa ccg gta acc gaa aac aag
atc cga tgc 528 Asp Leu Lys Asp Tyr Leu Lys Pro Val Thr Glu Asn Lys
Ile Arg Cys
165 170 175 ccc gac ccg gcc gtt aaa gtc gaa tcc gga ttc tta gat ctc
tac act 576 Pro Asp Pro Ala Val Lys Val Glu Ser Gly Phe Leu Asp Leu
Tyr Thr 180 185 190 gac aaa gac aca acc tgc aaa ttc gcg aga ttc tca
gcg cgt gaa cag 624 Asp Lys Asp Thr Thr Cys Lys Phe Ala Arg Phe Ser
Ala Arg Glu Gln 195 200 205 att tta acg gag gtg aaa cgg tta gtg gaa
gaa cac ggc gac gac gat 672 Ile Leu Thr Glu Val Lys Arg Leu Val Glu
Glu His Gly Asp Asp Asp 210 215 220 gat tcc gat tta agc atc acc gtg
acg gga cac agt ctc ggc ggc gcg 720 Asp Ser Asp Leu Ser Ile Thr Val
Thr Gly His Ser Leu Gly Gly Ala 225 230 235 240 tta gcg ata tta agc
gcg tac gat ata gcg gag atg aga ttg aat cgg 768 Leu Ala Ile Leu Ser
Ala Tyr Asp Ile Ala Glu Met Arg Leu Asn Arg 245 250 255 agt aag aaa
ggg aaa gtg att ccg gtg acg gtg ttg aca tac gga gga 816 Ser Lys Lys
Gly Lys Val Ile Pro Val Thr Val Leu Thr Tyr Gly Gly 260 265 270 ccg
aga gtt ggg aac gtt agg ttt agg gag agg atg gag gaa ttg gga 864 Pro
Arg Val Gly Asn Val Arg Phe Arg Glu Arg Met Glu Glu Leu Gly 275 280
285 gtg aaa gtg atg aga gta gtg aat gtt cac gac gtg gtt ccc aag tcg
912 Val Lys Val Met Arg Val Val Asn Val His Asp Val Val Pro Lys Ser
290 295 300 ccg gga ttg ttt ttg aac gag agt aga cct cac gcg ctg atg
aag ata 960 Pro Gly Leu Phe Leu Asn Glu Ser Arg Pro His Ala Leu Met
Lys Ile 305 310 315 320 gcg gag ggg ttg ccg tgg tgt tat agc cac gtg
ggg gag gag ctg gcg 1008 Ala Glu Gly Leu Pro Trp Cys Tyr Ser His
Val Gly Glu Glu Leu Ala 325 330 335 ttg gat cat cag aac tcg ccg ttt
ctt aaa cct tcc gtt gat gtt tct 1056 Leu Asp His Gln Asn Ser Pro
Phe Leu Lys Pro Ser Val Asp Val Ser 340 345 350 act gct cat aat ctt
gaa gct atg ctt cat tta ctt gac ggg tat cat 1104 Thr Ala His Asn
Leu Glu Ala Met Leu His Leu Leu Asp Gly Tyr His 355 360 365 gga aaa
gga gag aga ttt gtg ctg tcg agt ggg aga gac cat gcg cta 1152 Gly
Lys Gly Glu Arg Phe Val Leu Ser Ser Gly Arg Asp His Ala Leu 370 375
380 gtg aac aaa gcg tcg gac ttt ttg aaa gag cat tta caa att cca ccg
1200 Val Asn Lys Ala Ser Asp Phe Leu Lys Glu His Leu Gln Ile Pro
Pro 385 390 395 400 ttt tgg cgt caa gac gcg aat aaa gga atg gtt cgg
aac agt gaa ggt 1248 Phe Trp Arg Gln Asp Ala Asn Lys Gly Met Val
Arg Asn Ser Glu Gly 405 410 415 cgt tgg att caa gcc gag cgt ctc cgt
ttt gag gat cat cat tct cct 1296 Arg Trp Ile Gln Ala Glu Arg Leu
Arg Phe Glu Asp His His Ser Pro 420 425 430 gat atc cac cac cat ctc
tct cag ctc cgt ctt gat cat cct tgt taa 1344 Asp Ile His His His
Leu Ser Gln Leu Arg Leu Asp His Pro Cys 435 440 445 19 447 PRT
Arabidopsis thaliana 19 Met Thr Ala Glu Asp Ile Arg Arg Arg Asp Lys
Lys Thr Glu Glu Glu 1 5 10 15 Arg Arg Leu Arg Asp Thr Trp Arg Lys
Ile Gln Gly Glu Asp Asp Trp 20 25 30 Ala Gly Leu Met Asp Pro Met
Asp Pro Ile Leu Arg Ser Glu Leu Ile 35 40 45 Arg Tyr Gly Glu Met
Ala Gln Ala Cys Tyr Asp Ala Phe Asp Phe Asp 50 55 60 Pro Ala Ser
Lys Tyr Cys Gly Thr Ser Arg Phe Thr Arg Leu Glu Phe 65 70 75 80 Phe
Asp Ser Leu Gly Met Ile Asp Ser Gly Tyr Glu Val Ala Arg Tyr 85 90
95 Leu Tyr Ala Thr Ser Asn Ile Asn Leu Pro Asn Phe Phe Ser Lys Ser
100 105 110 Arg Trp Ser Lys Val Trp Ser Lys Asn Ala Asn Trp Met Gly
Tyr Val 115 120 125 Ala Val Ser Asp Asp Glu Thr Ser Arg Asn Arg Leu
Gly Arg Arg Asp 130 135 140 Ile Ala Ile Ala Trp Arg Gly Thr Val Thr
Lys Leu Glu Trp Ile Ala 145 150 155 160 Asp Leu Lys Asp Tyr Leu Lys
Pro Val Thr Glu Asn Lys Ile Arg Cys 165 170 175 Pro Asp Pro Ala Val
Lys Val Glu Ser Gly Phe Leu Asp Leu Tyr Thr 180 185 190 Asp Lys Asp
Thr Thr Cys Lys Phe Ala Arg Phe Ser Ala Arg Glu Gln 195 200 205 Ile
Leu Thr Glu Val Lys Arg Leu Val Glu Glu His Gly Asp Asp Asp 210 215
220 Asp Ser Asp Leu Ser Ile Thr Val Thr Gly His Ser Leu Gly Gly Ala
225 230 235 240 Leu Ala Ile Leu Ser Ala Tyr Asp Ile Ala Glu Met Arg
Leu Asn Arg 245 250 255 Ser Lys Lys Gly Lys Val Ile Pro Val Thr Val
Leu Thr Tyr Gly Gly 260 265 270 Pro Arg Val Gly Asn Val Arg Phe Arg
Glu Arg Met Glu Glu Leu Gly 275 280 285 Val Lys Val Met Arg Val Val
Asn Val His Asp Val Val Pro Lys Ser 290 295 300 Pro Gly Leu Phe Leu
Asn Glu Ser Arg Pro His Ala Leu Met Lys Ile 305 310 315 320 Ala Glu
Gly Leu Pro Trp Cys Tyr Ser His Val Gly Glu Glu Leu Ala 325 330 335
Leu Asp His Gln Asn Ser Pro Phe Leu Lys Pro Ser Val Asp Val Ser 340
345 350 Thr Ala His Asn Leu Glu Ala Met Leu His Leu Leu Asp Gly Tyr
His 355 360 365 Gly Lys Gly Glu Arg Phe Val Leu Ser Ser Gly Arg Asp
His Ala Leu 370 375 380 Val Asn Lys Ala Ser Asp Phe Leu Lys Glu His
Leu Gln Ile Pro Pro 385 390 395 400 Phe Trp Arg Gln Asp Ala Asn Lys
Gly Met Val Arg Asn Ser Glu Gly 405 410 415 Arg Trp Ile Gln Ala Glu
Arg Leu Arg Phe Glu Asp His His Ser Pro 420 425 430 Asp Ile His His
His Leu Ser Gln Leu Arg Leu Asp His Pro Cys 435 440 445 20 27 DNA
Artificial Sequence Description of Artificial Sequence Synthetic
Primer 20 atgtctagag aagatattgc gcggcga 27 21 28 DNA Artificial
Sequence Description of Artificial Sequence Synthetic Primer 21
gatgagctcg acgaagctga gagagatg 28 22 5 PRT Artificial Sequence
Description of Artificial Sequence Synthetic peptide motif 22 Gly
His Ser Leu Gly 1 5
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