Abstract:
A novel human corticotropin releasing hormone (CRH) receptor which is a splice variant of the human CRH 2  receptor subfamily and is designated human CRHR2γ. Fragments of CRHR2γ. Nucleic acid molecules which encode CRHR2γ and fragments, expression vectors comprising the nucleic acid molecules, and host cells containing the expression vectors. Antibodies and antibody fragments capable of binding the novel receptor. Nucleic acid molecules capable of hybridizing with the above nucleic acid molecules. Use of the novel receptor and receptor fragments, antibodies and antibody fragments in testing compounds for CRH antagonist activity and in treating diseases.

Description:
This applications claims priority to provisional application number 60/018,199, filed May 23,1996. 
     FIELD OF THE INVENTION 
     This invention relates to corticotropin-releasing hormone (&#34;CRH&#34;) (also known as corticotropin-releasing factor, or CRF). More particularly, the invention relates to CRH receptors (&#34;CRHR&#34;), specifically subfamily 2 of CRH receptors (&#34;CRH 2  receptors&#34; or &#34;CRHR2&#34;). 
     BACKGROUND OF THE INVENTION 
     CRH is a major neuropeptide mediator of the hypothalamic-pituitary-adrenocortical axis. It binds to plasma membrane receptors in the brain, pituitary, adrenals and spleen. It plays an important role in stress-responses and stress-induced disorders. 
     Neurocrine Biosciences, Inc. WO 95/34651, published Dec. 12, 1995, reports rat CRF 2 α  receptor (&#34;rat CRFR2α&#34;), rat CRF 2 β receptor (&#34;rat CRFR2β&#34;), and human CRF 2 α  receptor (&#34;human CRFR2α&#34;). Rat CRFR2α cDNA was isolated from a rat brain hypothalamus cDNA library. Rat CRFR2β cDNA was isolated from a rat brain cDNA library. Human CRFR2α receptor cDNA was isolated from a human brain cerebral cortex cDNA library. The cDNA molecules were sequenced, and the amino acid sequences of the receptor molecules were deduced from the cDNA sequences. 
     WO 95/34651 states that CRFR2α and CRFR2β can be cloned or synthesized and utilized to generate antibodies, which in turn can be utilized in flow cytometry to sort CRF 2  receptor-bearing cells, in histochemistry to stain CRF 2  receptor-bearing tissues, or in therapy to block binding of CRF to CRF 2  receptors. The application also states that the CRF 2  receptors can be used in various assays to identify compounds which bind the CRF 2  receptors, including agonists and antagonists. 
     SUMMARY OF THE INVENTION 
     We report here the cloning and characterization of a novel CRH receptor. Complementary DNA (&#34;cDNA&#34;) was isolated from a human amygdala cDNA library and used to express a 397-amino acid protein with approximately 96% amino acid identity to the known human CRHR2α. 
     Sequence of the cDNA is shown in Sequence I.D. 1. Predicted sequence of the protein is shown in Sequence I.D. 2. The nucleotide sequence is identical to the nucleotide sequence for human CRHR2α (Sequence I.D. 3) from nucleotide 212 (Sequence I.D. 1). The predicted amino acid sequence is identical to the predicted amino acid sequence of human CRHR2α from amino acid 21. Thus the protein is a splice variant of the human CRH 2  receptor subfamily, and is designated &#34;human CRH2γ receptor&#34; or &#34;human CRHR2γ&#34;. 
     As described below, the original CRHR2γ clone isolated from the human brain amygdala cDNA library contained a single codon deletion of three nucleotides (CAG), at 425-427 of Sequence I.D. 1. The deleted codon is present at a putative splice site in CRHR2γ and may reflect inaccuracy of splicing or alternative splicing choices at the splice junction for this individual cDNA clone. Both forms of CRHR2γ transcripts, those with and without the codon 425-427 of Sequence I.D. 1, have been detected at approximately equal levels by reverse transcriptase polymerase chain reaction amplification (RT-PCR) of mRNA from human brain. 
     Various cloning strategies have failed to identify the rat CRHR2γ homolog. Analysis of genomic DNA from humans and rats suggest the absence of this receptor gene in rat. While we have not excluded the possibility that CRHR2γ may be present in other species, at the moment it has only been found in humans and, thus, may be human specific. 
     Human CRHR2γ, when expressed in HEK293-EBNA cells, binds CRH, sauvagine and urotensin with the expected potency of stimulation of adenylate cyclase activity (sauvagine&gt;urotensin&gt;rat/human CRH ), as measured by intracellular cAMP accumulation. The CRH antagonist a-helical CRH (9-41) inhibits binding of the agonist peptide, CRH, and blocks the CRH-stimulated increase in intracellular cAMP. By RT-PCR analysis, the human CRH 2  γ receptor mRNA is present in human brain, in particular, amygdala, hippocampus, and has a distinct distribution of expression compared to the α and β isoforms of CRHR2. These differences in expression patterns may be significant for disease pathology and treatment. 
     This invention includes the following embodiments: 
     An isolated nucleic acid molecule encoding human CRHR2γ, including an isolated nucleic acid molecule comprising the sequence of nucleotides in Sequence I.D. No. 1 from nucleotide number 152 to nucleotide number 1342, and an isolated nucleic acid molecule comprising the same sequence but with deletion of the 425-427 CAG codon; also including an isolated nucleic acid molecule which encodes the sequence of amino acids in Sequence I.D. No. 2, and an isolated nucleic acid molecule which encodes the same sequence, but with deletion of the Gln residue at position 92. 
     An isolated nucleic acid molecule encoding the N-terminal extracellular domain of human CRHR2γ, including an isolated nucleic acid molecule comprising the sequence of nucleotides in Sequence I.D. No. 1, from nucleotide number 152 to nucleotide number 211, and also including an isolated nucleic acid molecule which encodes a protein having the sequence of amino acids in Sequence I.D. No. 2, from amino acid number 1 to amino acid number 20. 
     A recombinant expression vector comprising a promoter operably linked to any of the nucleic acid molecules described above, and a host cell containing such a recombinant expression vector. 
     An isolated human CRHR2γ, including an isolated human CRHR2γ with amino acid sequence of Sequence I.D. No. 2 and an isolated human CRHR2γ with the same sequence but with deletion of the Gin residue at position 92. 
     An isolated protein comprising the N-terminal extracellular domain of human CRHR2γ, including an isolated protein having the amino acid sequence of Sequence I.D. No. 2, from amino acid number 1 to amino acid number 20. 
     An isolated antibody or antibody fragment capable of specifically binding to a human CRHR2γ, especially an isolated antibody or fragment capable of specifically binding to the N-terminal extracellular domain of human CRHR2γ, including an isolated antibody or fragment capable of specifically binding to a protein having the amino acid sequence of Sequence I.D. No. 2, from amino acid number 1 to amino acid number 20. 
     An isolated nucleic acid molecule capable of specifically hybridizing with any of the nucleic acid molecules described above. 
     A method of testing a compound for pharmacological activity as a CRH antagonist which comprises adding the compound and a labeled CRH agonist such as  125  I sauvagine to a sample containing human CRHR2γ or a fragment thereof, such as the N-terminal extracellular domain of human CRHR2γ, and measuring the extent to which the compound inhibits binding of the labeled agonist to the human CRHR2γ or fragment. 
     A method of treating a disease in a mammal which is associated with elevated levels of CRH or ACTH, comprising administering to the mammal a therapeutically effective amount of a human CRHR2γ or fragment thereof, such as the N-terminal extracellular domain of human CRHR2γ. 
     A method of treating a disease in a mammal which is associated with elevated levels of CRH or ACTH, comprising administering to the mammal a therapeutically effective amount of an antibody or antibody fragment capable of specifically binding to a human CRHR2γ or fragment thereof, such as the N-terminal extracellular domain of human CRHR2γ. 
     Diseases which are associated with elevated levels of CRH or ACTH include those mentioned in WO95/34651, i.e., Cushing&#39;s Disease, alcoholism, anorexia nervosa, pituitary tumors and other pituitary disorders, hypotension, immune system disorders such as arthritis, anxiety and depression. 
     DETAILED DESCRIPTION 
     The present invention relates to a novel CRHR2 protein. More particularly, the invention relates to an isolated nucleic acid encoding a novel splice isoform of the CRHR2 subfamily. This new subfamily member is designated CRHR2γ. Nucleic acids encoding CRHR2γ were identified in a human brain amygdala cDNA library using a DNA probe consisting of rat CRHR2 sequence obtained by polymerase chain reaction (PCR) amplification. 
    
    
     EXAMPLE 1 
     Cloning and sequencing of CRHR2γ cDNA A 536-bp polymerase chain reaction (&#34;UPCR&#34;) fragment containing the nucleotides 1-536 of rat CRHR2α receptor cDNA (coding region) was used to screen a λgt11 human brain amygdala cDNA library (Clontech). The probe was labeled with  α- 32  P!dCTP using a random primed labeling kit (Gibco-BRL). The plaques were lifted onto nitrocellulose membranes (Schleicher &amp; Schuell), then denatured, neutralized and rinsed. The membranes were prehybridized at 60° C. in 6×SSC, 0.05×blotto (1×blotto: 5% non-fat dry milk, 0.02% sodium azide) and 100 μg/ml herring sperm DNA for 2 hours and then hybridized at the same condition with 1×10 6  cpm/ml labeled probe overnight. Membranes were washed with 2×SSC / 0.1% SDS consecutively at RT and 60° C. for 30 minutes each, then twice with 0.5×SSC / 0.1% SDS at 60° C. for 30 minutes. Approximately 8.5×10 5  phage plaques were screened and 5 unique hybridization-positive plaques were isolated and purified. λ phage DNA was isolated by Qiagen lambda kit and further characterized by Southern analysis. After subcloning CDNA inserts into pBluescript II SK (Stratagene), the DNA sequence of both strands was determined using automated fluorescent dideoxynucleotide chain termination methodology (Rosenthal, A. and Chamock-Jones, D. S.1993). 
     Of the five positive cDNA clones, one was homologous to the human CRHR1 (hCRHR1) subtype but revealed the inclusion of putative intronic sequence. Four of the cDNA clones represented genes of the human CRHR2 (hCRHR2) receptor subfamily. Two of these clones contained sequence that indicated a novel member of the hCRHR2 receptor subfamily which was an alternatively spliced form to the α or β hCRHR2 receptors. These clones included novel nucleotide sequence and predicted amino acid sequence in the presumptive extracellular portion of the receptor protein. 
     Human CRHR2γ contains a 1555-bp insert with a 1191-bp open reading frame encoding 397-a.a. protein (Sequence I.D. No. 1). Compared to known rat CRHR2α, this clone showed approximately 87% identity at the nucleotide level over the entire coding region and 90% identity at the amino acid level. When compared to the hCRHRI(Vita et al., 1993), hCRHR2γ is approximately 72% similar at the nucleotide and amino acid level. Identity between hCRHR2γ and hCRHR2α is more significant with 97% identity. According to the hydrophobicity analysis of hCRHR2γ amino acid sequence, it contains seven hydrophobic regions corresponding to seven putative transmembrane domains (TopPred II algorithm), and five potential N-linked glycosylation sites in the N terminus (Sequence I.D. No. 2). In all the species of cloned CRHR2 (Kishimoto et al., 1995; Lovenberg et aL, 1995; Perrin et al, 1995), all but one of the potential N-link glycosylation sites are preserved among them. 
     To obtain additional 5&#39; sequence and validate the identity of the various alternatively spliced forms of the hCRHR2 gene, we used anchor PCR strategies to assess the sequence of the 5&#39; end of messenger RNA containing sequence from the common region of the hCRHR2 subfamily. Three consecutive antisense oligonucleotide primers (SEQUENCE I.D. 4,5,6) were designed from the common sequence of hCRHR2, 3&#39; from the putative splice site. After examining human brain hypothalamus, hippocampus and frontal cortex RNA by nested rounds of RT-PCR, we isolated an 5&#39;RACE clone (from frontal cortex mRNA) with identical overlapping sequence to the hCRHR2γ clone and additional 5&#39; non-coding sequence. 
     The original CRHR2γ clone isolated from the human brain amygdala cDNA library contained a single codon deletion of three nucleotides (CAG), at 425-427 of Sequence I.D. 1, compared to human homologs of CRHR α and β. The deleted three nucleotides (CAG) are present at a putative splice site in CRHR2γ and may reflect inaccuracy of splicing or an alternative splicing choice at the splice junction for this individual cDNA clone. The codon, CAG, which encodes for the amino acid glutamine, represents the consensus sequence at the 3&#39; end of intronic sequence. 
     Both forms of CRHR2 gamma transcripts, those with and without the codon 425-427 of Sequence I.D. 1, have been detected at approximately equal levels by reverse transcriptase polymerase chain reaction amplification (RT-PCR) of mRNA from human brain. Thus, both transcript forms appear to be naturally transcribed, alternatively spliced forms of the CRHR2 gene. 
     Interestingly, unlike many other genes encoding G-protein-coupled receptors which lack introns in their coding sequence, the CRH receptor family appears to generate multiple isoforms by alternative RNA splicing. The mouse CRH receptor gene comprises at least 12 exons, spanning more than 14 Kb (Chen et. al ). Based on preliminary cloning and PCR analysis, we believe there might be more than two intron/exon spliced sites in hCRHR2 gene. Within the neuropeptide receptor family (Segre, G. R. and Goldring S. R.,1993), a rat growth hormone releasing hormone (GHRH) receptor gene has been reported that contains numerous introns within the coding region (Mayo, K E.,1992). The mRNA of porcine calcitonin receptor (CTR) gene also encompasses 14 exons with 12 exons encoding the protein (Zolnierowicz S. et al, 1994). The human glucagon receptor gene spans over 5.5 Kb and is interrupted by 12 introns (Lok S. et al., 1994) The type I human vasoactive intestinal peptide (VIP) receptor gene spans approximately 22 kb and is composed of 13 exons and 12 introns (Sreedharan S. P. et al., 1995). Extensive alternative splicing of mRNA represents a unique characteristic in this CRH/calcitonin/GHRH/glucagon/VIP family of G protein-coupled seven transmembrane domain receptors. 
     Tissue Distribution 
     To detect the human CRHR2γ message in various brain regions, we used the RT-PCR to examine the total and/or poly-A enriched RNA of human brain tissues. Specific oligonucleotide primers (Sequence I.D. 7,8) were used to PCR amplify CRHR2γ sequences. The resulting products were electrophoretically separated through an agarose gel and subsequently blotted to a nitrocellulose membrane for hybridization analysis with a  32  P-labeled DNA probe for CRHR2γ. The signal for CRHR2γ was detected most abundantly in the human amygdala and hippocampus. 
     Heterologous Expression. 
     For expression studies, the full length CRHR2 γ cDNA (original cDNA library clone) was subcloned between the Xhol and Xbal restriction sites of expression vector phchm3AR (Shen et al., 1995), creating the CRHR2 γ expression plasmid ph-a10-18. This vector is a modification of pHEBo, an Epstein Barr Viral origin of replication plasmid (Sugden et al., 1985) into which a CMV immediate early promoter, a multicloning site, and the SV40 small t intron and early poly adenylation signal regions have been added. This plasmid replicates episomally in primate cells expressing the EBV nuclear antigen 1 (Shen et al., 1995). 
     A stable cell line expressing CRHR2 γ was established by transfecting the plasmid ph-a10-18 into HEK293EBNA cells (Invitrogen) using LipofectAMINE (GibcoBRL). This plasmid contains the CRHR2 γ gene under the control of the CMV immediate early promoter, the EBV oriP for maintenance of the plasmid as an extrachromosomal element in the appropriate cells (nonrodent mammalian cells expressing EBNA), and the hph gene from E. coli to yield resistance to hygromycin B. HEK293EBNA cells were grown in Dulbecco&#39;s modified Eagle medium containing 10% fetal bovine serum at 37° C. in a humid environment with 5% CO 2 . Cells were plated at a density of 4×10 5  cells/well in a 6-well plate and transfected with 1 μg of plasmid per well the following day. Within 24 hours after transfection, the cells were expanded into 150 mm plates; within 24 hours after expansion, hygromycin B was added to the media at a concentration of 300 μg/ml to select for transfectants. All cells resistant to hygromycin B after a week must be harboring the plasmid within them; since no integration is necessary for the maintenance of the plasmid within these cells, all transfected cells are essentially the same and no further subcloning was necessary. 
     Receptor Binding Assays 
       125  l-tyr-0-sauvagine was used in receptor binding studies with membranes isolated from HEK293EBNA cells expressing the CRHR2 γ receptor. Buffer consisted of 50 mM HEPES, 10 mM MgCI 2 , 2 mM EGTA, and 1 μg/ml each of aprotinin, leupeptin, and pepstatin at a final pH of 7.0. Bacitracin at 0.15 mM and ovalbumin at 0.1% were added to the buffer on the day of use. Assays were performed at 23° C. for 4 hours in a final volume of 200 μl in 96-well microtiter plates. Reactions were initiated by the addition of 10-20 μg of membrane homogenates and terminated by rapid filtration through presoaked (0.3% polyethyleneimine) glass fiber filters using an Inotech 96-well harvester. The filters were washed quickly 3×with ice-cold solution (PBS+0.01% TritonX-100, pH7.2), dried briefly, then placed into polystyrene tubes and counted on an Isomedic 10/880 γ counter (counting efficiency ˜80%). Data was analyzed by nonlinear regression analysis using the computer program MacLigand. Determinations were made from at least 3 separate experiments. 
     Saturation experiments were performed with 23 different concentrations of sauvagine over the range of 4 pM to 100 nM, using increasing concentrations of  125  l-tyr-0-sauvagine from 4 pM to 1 nM, and 0.25 nM  125  l-tyr-0-sauvagine spiked with unlabelled sauvagine from 1 nM to 100 nM. Nonspecific binding was defined by the presence of 1 μM a-helical CRH (9-41). The data analysis indicates the presence of two affinity states of the receptor: the high affinity receptor has a Kd of ˜60 pM, and the low affinity one of ˜5 nM. The Bmax of the high affinity receptor is ˜100 fmole/mg protein and that of the low affinity receptor is ˜1.6 pmole/mg protein. 
     Displacement studies looked at varying concentrations of r/h CRH, a-helical CRH(9-41), urotensin, and urocortin for their ability to displace 60-70 pM  125  l-tyr-0-sauvagine. The approximate IC50s determined for these peptides are: r/h CRH 25 nM; a-helical CRH (9-41) 7 nM; urotensin 5 nM; urocortin 2 nM. 
     Whole Cell Adenylate Cyclase Assay: 
     HEK293EBNA cells expressing the CRHR2 γ were incubated in DMEM with low serum (0.1% FBS) at 37° C., 5% CO 2  for at least 2 hrs before the addition of isobytylmethoxyxanthine (IBMX) to the media at a final concentration of 0.1 mM. The cells were incubated with the IBMX for 30 minutes; test peptides or compounds were then added to the media and incubated therein for 25-30 min. The media was then aspirated from the cells and replaced with ice cold sodium acetate buffer containing 1 mM IBMX. The cells were then disrupted by a freeze-thaw, followed by sonication. Supernatants were assayed for cAMP levels with PerSeptive Diagnostics EIA Kit. Results indicate that respective EC 50  of r/h CRH&gt;urotensin&gt;sauvagine for cAMP stimulation at this receptor. The CRH receptor antagonist a-helical CRH (9-41) inhibits the stimulation of both r/h CRH and sauvagine. 
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         __________________________________________________________________________SEQUENCE LISTING(1) GENERAL INFORMATION:(iii) NUMBER OF SEQUENCES:8(2) INFORMATION FOR SEQ ID NO:1:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:1558 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(ii) FEATURE:(A) NAME/KEY:CDS(B) LOCATION:152...1342(iii) SEQUENCE DESCRIPTION:SEQ ID NO:1:CTGTGCTCAAGCAATCTGCCTACCTTGGCTTCCCCAAGTGCTGAGATTAT50GGGTGTGAGCCACTGCACCTGGCCAAGAATCCGAATGGATTCAAAGATAC100CTTGAAATAATTCCTCAATGCAACACACACACATATGCCAGGGTTGGT148CAAATGGGAAGAGAGCCTTGGCCTGAAGACAGGGACCTGGGC190MetGlyArgGluProTrpProGluAspArgAspLeuGly1510TTTCCTCAGCTCTTCTGCCAAGGTCCCTACTCCTACTGCAAC232PheProGlnLeuPheCysGlnGlyProTyrSerTyrCysAsn152025ACGACCTTGGACCAGATCGGAACGTGCTGGCCCCGCAGCGCT274ThrThrLeuAspGlnIleGlyThrCysTrpProArgSerAla303540GCCGGAGCCCTCGTGGAGAGGCCGTGCCCCGAGTACTTCAAC316AlaGlyAlaLeuValGluArgProCysProGluTyrPheAsn455055GGCGTCAAGTACAACACGACCCGGAATGCCTATCGAGAATGC358GlyValLysTyrAsnThrThrArgAsnAlaTyrArgGluCys6065TTGGAGAATGGGACGTGGGCCTCAAAGATCAACTACTCACAG400LeuGluAsnGlyThrTrpAlaSerLysIleAsnTyrSerGln707580TGTGAGCCCATTTTGGATGACAAGCAGAGGAAGTATGACCTG442CysGluProIleLeuAspAspLysGlnArgLysTyrAspLeu859095CACTACCGCATCGCCCTTGTCGTCAACTACCTGGGCCACTGC484HisTyrArgIleAlaLeuValValAsnTyrLeuGlyHisCys100105110GTATCTGTGGCAGCCCTGGTGGCCGCCTTCCTGCTTTTCCTG526ValSerValAlaAlaLeuValAlaAlaPheLeuLeuPheLeu115120125GCCCTGCGGAGCATTCGCTGTCTGCGGAATGTGATTCACTGG568AlaLeuArgSerIleArgCysLeuArgAsnValIleHisTrp130135ACCCTCATCACCACCTTTATCCTGCGAAATGTCATGTGGTTC610AsnLeuIleThrThrPheIleLeuArgAsnValMetTrpPhe14014515CTGCTGCAGCTCGTTGACCATGAAGTGCACGAGAGCAATGAG652LeuLeuGlnLeuValAspHisGluValHisGluSerAsnGlu155160165GTCTGGTGCCGCTGCATCACCACCATCTTCAACTACTTCGTG694ValTrpCysArgCysIleThrThrIlePheAsnTyrPheVal170175180GTGACCAACTTCTTCTGGATGTTTGTGGAAGGCTGCTACCTG736ValThrAsnPhePheTrpMetPheValGluGlyCysTyrLeu185190195CACACGGCCATTGTCATGACCTACTCCACTGAGCGCCTGCGC778HisThrAlaIleValMetThrTyrSerThrGluArgLeuArg200205AAGTGCCTCTTCCTCTTCATCGGATGGTGCATCCCCTTCCCC820LysCysLeuPheLeuPheIleGlyTrpCysIleProPhePro210215220ATCATCGTCGCCTGGGCCATCGGCAAGCTCTACTATGAGAAT862IleIleValAlaTrpAlaIleGlyLysLeuTyrTyrGluAsn225230235GAACAGTGCTGGTTTGGCAAGGAGCCTGGCGACCTGGTGGAC904GluGlnCysTrpPheGlyLysGluProGlyAspLeuValAsp240245250TACATCTACCAAGGCCCCATCATTCTCGTGCTCCTGATCAAT946TyrIleTyrGlnGlyProIleIleLeuValLeuLeuIleAsn255260265TTCGTATTTCTGTTCAACATCGTCAGGATCCTAATGACAAAG988PheValPheLeuPheAsnIleValArgIleLeuMetThrLys270275TTACGCGCGTCCACCACATCCGAGACAATCCAGTACAGGAAG1030LeuArgAlaSerThrThrSerGluThrIleGlnTyrArgLys280285290GCAGTGAAGGCCACCCTGGTGCTCCTGCCCCTCCTGGGCATC1072AlaValLysAlaThrLeuValLeuLeuProLeuLeuGlyIle295300305ACCTACATGCTCTTCTTCGTCAATCCCGGGGAGGACGACCTG1114ThrTyrMetLeuPhePheValAsnProGlyGluAspAspLeu310315320TCACAGATCATGTTCATCTATTTCAACTCCTTCCTGCAGTCG1156SerGlnIleMetPheIleTyrPheAsnSerPheLeuGlnSer325330335TTCCAGGGTTTCTTCGTGTCTGTCTTCTACTGCTTCTTCAAT1198PheGlnGlyPhePheValSerValPheTyrCysPhePheAsn340345GGAGAGGTGCGCTCAGCCGTGAGGAAGAGGTGGCACCGCTGG1240GlyGluValArgSerAlaValArgLysArgTrpHisArgTrp350355360CAGGACCATCACTCCCTTCGAGTCCCCATGGCCCGGGCCATG1282GlnAspHisHisSerLeuArgValProMetAlaArgAlaMet365370375TCCATCCCTACATCACCCACACGGATCAGCTTCCACAGCATC1324SerIleProThrSerProThrArgIleSerPheHisSerIle380385390AAGCAGACGGCCGCTGTGTGACCCCTCGGTCGCCCACCTGCACAGCTC1372LysGlnThrAlaAlaVal395CCCTGTCCTCCTCCACCTTCTTCCTCTGGGTTCTCTGTGCTGGGCAGGCT1422CTCGTGGGGCAGGAGATGGGAGGGGAGAGACCAGCTCTCCAGCCTGGCAG1472GAAAGAGGGGGTGCGGCAGCCAAGGGGGACTGCAAGGGACAGGGATGAGT1522GGGGGCCACCAGGCTCAGCGCAAGAGGAAGCAGAGG1558(2) INFORMATION FOR SEQ ID NO:2:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:397 amino acids(B) TYPE:amino acid(C) TOPOLOGY:linear(ii) MOLECULE TYPE:protein(iii) SEQUENCE DESCRIPTION:SEQ ID NO:2:MetGlyArgGluProTrpProGluAspArgAspLeuGly1510PheProGlnLeuPheCysGlnGlyProTyrSerTyrCysAsn152025ThrThrLeuAspGlnIleGlyThrCysTrpProArgSerAla303540AlaGlyAlaLeuValGluArgProCysProGluTyrPheAsn455055GlyValLysTyrAsnThrThrArgAsnAlaTyrArgGluCys6065LeuGluAsnGlyThrTrpAlaSerLysIleAsnTyrSerGln707580CysGluProIleLeuAspAspLysGlnArgLysTyrAspLeu859095HisTyrArgIleAlaLeuValValAsnTyrLeuGlyHisCys100105110ValSerValAlaAlaLeuValAlaAlaPheLeuLeuPheLeu115120125AlaLeuArgSerIleArgCysLeuArgAsnValIleHisTrp130135AsnLeuIleThrThrPheIleLeuArgAsnValMetTrpPhe140145150LeuLeuGlnLeuValAspHisGluValHisGluSerAsnGlu155160165ValTrpCysArgCysIleThrThrIlePheAsnTyrPheVal170175180ValThrAsnPhePheTrpMetPheValGluGlyCysTyrLeu185190195HisThrAlaIleValMetThrTyrSerThrGluArgLeuArg200205LysCysLeuPheLeuPheIleGlyTrpCysIleProPhePro210215220IleIleValAlaTrpAlaIleGlyLysLeuTyrTyrGluAsn225230235GluGlnCysTrpPheGlyLysGluProGlyAspLeuValAsp240245250TyrIleTyrGlnGlyProIleIleLeuValLeuLeuIleAsn255260265PheValPheLeuPheAsnIleValArgIleLeuMetThrLys270275LeuArgAlaSerThrThrSerGluThrIleGlnTyrArgLys280285290AlaValLysAlaThrLeuValLeuLeuProLeuLeuGlyIle295300305ThrTyrMetLeuPhePheValAsnProGlyGluAspAspLeu310315320SerGlnIleMetPheIleTyrPheAsnSerPheLeuGlnSer325330335PheGlnGlyPhePheValSerValPheTyrCysPhePheAsn340345GlyGluValArgSerAlaValArgLysArgTrpHisArgTrp350355360GlnAspHisHisSerLeuArgValProMetAlaArgAlaMet365370375SerIleProThrSerProThrArgIleSerPheHisSerIle380385390LysGlnThrAlaAlaVal395(2) INFORMATION FOR SEQ ID NO:3:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:1233 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(iii) SEQUENCE DESCRIPTION:SEQ ID NO:3:ATGGACGCGGCACTGCTCCACAGCCTGCTGGAGGCCAACTGCAGCCTGGC50GCTGGCTGAAGAGCTGCTCTTGGACGGCTGGGGGCCACCCCTGGACCCCG100AGGGTCCCTACTCCTACTGCAACACGACCTTGGACCAGATCGGAACGTGC150TGGCCCCGCAGCGCTGCCGGAGCCCTCGTGGAGAGGCCGTGCCCCGAGTA200CTTCAACGGCGTCAAGTACAACACGACCCGGAATGCCTATCGAGAATGCT250TGGAGAATGGGACGTGGGCCTCAAAGATCAACTACTCACAGTGTGAGCCC300ATTTTGGATGACAAGCAGAGGAAGTATGACCTGCACTACCGCATCGCCCT350TGTCGTCAACTACCTGGGCCACTGCGTATCTGTGGCAGCCCTGGTGGCCG400CCTTCCTGCTTTTCCTGGCCCTGCGGAGCATTCGCTGTCTGCGGAATGTG450ATTCACTGGAACCTCATCACCACCTTTATCCTGCGAAATGTCATGTGGTT500CCTGCTGCAGCTCGTTGACCATGAAGTGCACGAGAGCAATGAGGTCTGGT550GCCGCTGCATCACCACCATCTTCAACTACTTCGTGGTGACCAACTTCTTC600TGGATGTTTGTGGAAGGCTGCTACCTGCACACGGCCATTGTCATGACCTA650CTCCACTGAGCGCCTGCGCAAGTGCCTCTTCCTCTTCATCGGATGGTGCA700TCCCCTTCCCCATCATCGTCGCCTGGGCCATCGGCAAGCTCTACTATGAG750AATGAACAGTGCTGGTTTGGCAAGGAGCCTGGCGACCTGGTGGACTACAT800CTACCAAGGCCCCATCATTCTCGTGCTCCTGATCAATTTCGTATTTCTGT850TCAACATCGTCAGGATCCTAATGACAAAGTTACGCGCGTCCACCACATCC900GAGACAATCCAGTACAGGAAGGCAGTGAAGGCCACCCTGGTGCTCCTGCC950CCTCCTGGGCATCACCTACATGCTCTTCTTCGTCAATCCCGGGGAGGACG1000ACCTGTCACAGATCATGTTCATCTATTTCAACTCCTTCCTGCAGTCGTTC1050CAGGGTTTCTTCGTGTCTGTCTTCTACTGCTTCTTCAATGGAGAGGTGCG1100CTCAGCCGTGAGGAAGAGGTGGCACCGCTGGCAGGACCATCACTCCCTTC1150GAGTCCCCATGGCCCGGGCCATGTCCATCCCTACATCACCCACACGGATC1200GCTTCCACAGCATCAAGCAGACGGCCGCTGTG1233(2) INFORMATION FOR SEQ ID NO:4:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:22 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(iii) SEQUENCE DESCRIPTION:SEQ ID NO:4:GGTCATACTTCCTCTGCTTGTC22(2) INFORMATION FOR SEQ ID NO:5:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:20 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(iii) SEQUENCE DESCRIPTION:SEQ ID NO:5:TCTCCAAGCATTCTCGATAG20(2) INFORMATION FOR SEQ ID NO:6:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:18 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(iii) SEQUENCE DESCRIPTION:SEQ ID NO:6:TACTTGACGCCGTTGAAG18(2) INFORMATION FOR SEQ ID NO:7:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:20 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(iii) SEQUENCE DESCRIPTION:SEQ ID NO:7:TCTCCAAGCATTCTCGATAG20(2) INFORMATION FOR SEQ ID NO:8:(i) SEQUENCE CHARACTERISTICS:(A) LENGTH:19 nucleotides(B) TYPE:nucleic acid(C) STRANDEDNESS:single(D) TOPOLOGY:linear(iii) SEQUENCE DESCRIPTION:SEQ ID NO:8:GATTATGGGTGTGAGCCAC19__________________________________________________________________________