SGIP peptides

Abstract

The present invention is directed to polynucleotides, polypeptides, peptides, variants and uses thereof for novel peptide fragments which have homology to motilin. Tissue distribution of the mRNA for the novel polypeptide fragment is specific to the stomach, small intestine and pancreas. Binding of the peptide fragment has been shown in kidney and small intestine. The present invention further includes agonists, antagonists, variants, antibodies and host cells expressing the cDNA encoding the novel SGIP peptide.

1 . An isolated polypeptide molecule consisting of an amino acid sequence selected from 
 a. residues 3 to 9 of SEQ ID NO:2;    b. residues 2 to 9 of SEQ ID NO:2;    c. residues 1 to 9 of SEQ ID NO:2    d. residues 3 to 10 of SEQ ID NO:2;    e. residues 2 to 10 of SEQ ID NO:2; and    f. residues 3 to 11 of SEQ ID NO:2,    wherein the polypeptide molecule has one amino acid substitution.    
     
     
         2 . The isolated polypeptide molecule according to  claim 1 , wherein the amino acid substitution is selected from 
 a. the amino acid at position 1 of SEQ ID NO:2 is substituted with serine, alanine, threonine, or methionine;    b. the amino acid at position 2 of SEQ ID NO:2 is substituted with glycine, alanine, threonine, or methionine;    c. the amino acid at position 3 of SEQ ID NO:2 is substituted with glycine, alanine, threonine, or methionine;    d. the amino acid at position 4 of SEQ ID NO:2 is substituted with tryptophan, tyrosine, leucine, valine, or isoleucine;    e. the amino acid at position 5 of SEQ ID NO:2 is substituted with isoleucine, valine, phenylalanine, or tyrosine;    f. the amino acid at position 6 of SEQ ID NO:2 is substituted with glycine, alanine, threonine, methionine, or proline;    g. the amino acid at position 7 of SEQ ID NO:2 is substituted with alanine, glycine, isoleucine, leucine, or valine;    h. the amino acid at position 8 of SEQ ID NO:2 is substituted with aspartic acid;    i. the amino acid at position 9 of SEQ ID NO:2 is substituted with arginine, lysine, phenylalanine, or tyrosine;    j. the amino acid at position 10 of SEQ ID NO:2 is substituted with asparagine, serine, threionine, histidine, alanine, glutamic acid, aspartic acid, lysine or arginine; or    k. the amino acid position 11 of SEQ ID NO:2 is substituted with glutamine, asparagine, serine, threionine, histidine, or alanine.    
     
     
         3 . An isolated polypeptide molecule consisting of an amino acid sequence selected from 
 a. residues 4 to 9 of SEQ ID NO:2;    b. residues 4 to 10 of SEQ ID NO:2; and    c. residues 4 to 11 of SEQ ID NO:2;    wherein the polypeptide molecule has one amino acid substitution.    
     
     
         4 . The isolated polypeptide molecule according to  claim 3 , wherein the amino acid substitution is selected from 
 a. the amino acid at position 4 of SEQ ID NO:2 is substituted with tryptophan, tyrosine, leucine, valine, or isoleucine;    b. the amino acid at position 5 of SEQ ID NO:2 is substituted with isoleucine, valine, phenylalanine, or tyrosine;    c. the amino acid at position 6 of SEQ ID NO:2 is substituted with glycine, alanine, threonine, methionine, or proline;    d. the amino acid at position 7 of SEQ ID NO:2 is substituted with glycine, alanine, isoleucine, leucine or valine;    e. the amino acid at position 8 of SEQ ID NO:2 is substituted with aspartic acid;    f. the amino acid at position 9 of SEQ ID NO:2 is substituted with arginine, lysine, phenylalanine, or tyrosine;    g. the amino acid at position 10 of SEQ ID NO:2 is substituted with asparagine, serine, threionine, histidine, alanine, glutamic acid, aspartic acid, lysine, or arginine; or    h. the amino acid at position 11 of SEQ ID NO:2 is substituted with glutamine, asparagine, serine, threionine, histidine, or alanine.