Polypeptide sequences of human EDG-1c

Abstract

Human EDG-1c polypeptidees and polynucleotides and methods for producing such polypeptides by recombinant techniques are disclosed. Human EDG-1c is identified as a selective receptor for sphingosine-1-phosphate (“S-1-P”) and for di-hydro S-1-P. Also disclosed are methods for discovering agonists and antagonists of the interaction between S-1-P and di-hydro S-1-P and their cellular receptor, human EDG-1c, which may have utility in the treatment of several human diseases and disorders, including, but not limited to the treatment of infections such as bacterial, fungal, protozoan and viral infections, particularly infections such as bacterial, fungal, protozoan and viral infections, particularly infections caused by HIV-1 or HIV-2; pain; cancers; diabetes, obesity; anorexia; bulimia; asthma; Parkinson's disease; acute heart failure; hypotension; hypertension; urinary retention; osteoporosis; angina pectoris; myocardial infarction; stroke; congestive heart failure; left ventricular hypertrophy; arrythmias; restenosis after coronary artery angioplasty; vascular sclerosis; deleterious fibrosis; atherosclerosis; inflammation; angiogenesis; wound healing; ulcers; asthma; allergies; benign prostatic hypertrophy; migraine; vomiting; psychotic and neurological disorders, including anxiety, schizophrenia, manic depression, depression, delirium, dementia, and severe mental retardation; degenerative diseases, such as neurodegenerative diseases and ischemic stroke; and dyskinesias, such as Huntington's disease or Gilles dela Tourett's syndrome.

What is claimed is:  
     
         1 . An isolated polynucleotide comprising a nucleotide sequence encoding the polypeptide of SEQ ID NO:2; or a nucleotide sequence complementary to said nucleotide sequence.  
     
     
         2 . The polynucleotide as claimed in  claim 1 , wherein said polynucleotide is DNA or RNA.  
     
     
         3 . The polynucleotide as claimed in  claim 1 , wherein said nucleotide sequence comprises SEQ ID NO:1.  
     
     
         4 . An isolated polypeptide comprising the polypeptide sequence set forth in SEQ ID NO:2.  
     
     
         5 . An expression system comprising a polynucleotide capable of producing a polypeptide as claimed in  claim 4  when said expression system is in a compatible host cell.  
     
     
         6 . A process for producing a recombinant host cell comprising the step of introducing the expression system as claimed in  claim 5  into a cell, such that the host cell, under appropriate culture conditions, produces said polypeptide.  
     
     
         7 . A recombinant host cell produced by the process as claimed in  claim 6 .  
     
     
         8 . A membrane of a recombinant host cell as claimed in  claim 7  expressing said polypeptide.  
     
     
         9 . A process for producing a polypeptide comprising culturing a host cell as claimed in  claim 6  under conditions sufficient for the production of said polypeptide and recovering the polypeptide from the culture.  
     
     
         10 . An antibody immunospecific for the polypeptide as claimed in  claim 4 .  
     
     
         11 . A method for identifying agonist or antagonist of the of polypeptide as claimed in  claim 4  comprising: 
 (a) contacting a cell expressing on the surface thereof the polypeptide, said polypeptide being associated with a second component capable of providing a detectable signal in response to the binding of a compound to said polypeptide, with a compound to be screened under conditions to permit binding to the polypeptide; and  
 (b) determining whether the compound binds to and activates or inhibits the polypeptide by measuring the level of a signal generated from the interaction of the compound with the polypeptide.  
 
     
     
         12 . The method as claimed in  claim 11 , wherein said method further comprises conducting the identification of an agonist or antagonist in the presence of labeled or unlabeled sphingosine 1-phosphate or di-hydo sphingosine 1-phosphate.  
     
     
         13 . A method for identifying an agonist or antagonist of the polypeptide as claimed in  claim 4  comprising: 
 determining the inhibition of binding of a ligand to cells expressing the polypeptide on the surface thereof, or to cell membranes containing the polypeptide, in the presence of a candidate compound under conditions to permit binding to the polypeptide, and determining the amount of ligand bound to the polypeptide, such that a compound capable of causing reduction of binding of a ligand is an agonist or antagonist.  
 
     
     
         14 . The method as claimed in  claim 13 , wherein the ligand is labeled or unlabeled sphingosine-1-phosphate or di-hydro sphingosine 1-phosphate.  
     
     
         15 . A method for screening to identify compounds that stimulate or that inhibit a function or level of the polypeptide as claimed in  claim 4 , comprising a method selected from the group consisting of: 
 (a) measuring or, quantitatively or qualitatively, detecting the binding of a candidate compound to the polypeptide (or to the cells or membranes bearing the polypeptide) or a fusion protein thereof by means of a label directly or indirectly associated with the candidate compound;    (b) measuring the competition of the binding of a candidate compound to the polypeptide (or to the cells or membranes bearing the polypeptide) or a fusion protein thereof in the presence of a labeled competitor, preferably sphingosine-1-phosphate or di-hydro sphingosine 1-phosphate;    (c) testing whether the candidate compound results in a signal generated by activation or inhibition of the polypeptide, using detection systems appropriate to the cells or cell membranes bearing the polypeptide;    (d) mixing a candidate compound with a solution comprising said polypeptide to form a mixture, measuring activity of the polypeptide in the mixture, and comparing the activity of the mixture to a to a control mixture which contains no candidate compound; or    (e) detecting the effect of a candidate compound on the production of mRNA encoding said polypeptide and said polypeptide in cells.    
     
     
         16 . An antagonist identified by the method as claimed in  claim 15 .  
     
     
         17 . An agonist identified by the method as claimed in  claim 15 .  
     
     
         18 . A method for the treatment of a subject having need to inhibit activity or expression of human EDG-1c polypeptide comprising: 
 (a) administering to the subject a therapeutically effective amount of an antagonist as claimed in  claim 16 .    
     
     
         19 . The method as claimed in  claim 18 , wherein the subject is afflicted with a disease selected from the group consisting of: congestive heart failure, left ventricular hypertrophy, and arrythmias.