Patent ID: 7662574

Claim:
A method for screening a compound that alters the binding property between a ligand and a protein or a salt thereof, which comprises: (i) providing an isolated protein or a salt thereof comprising an amino acid sequence selected from the group consisting of: (a) SEQ ID NO: 54; (b) SEQ ID NO: 54 of which 1 to 30 amino acids are deleted; (c) SEQ ID NO: 54 to which 1 to 30 amino acids are added; (d) SEQ ID NO: 54 in which 1 to 30 amino acids are substituted by other amino acids; and (e) a combination of the amino acid sequences of(b) to (d); wherein said protein is capable of binding a partial peptide of a polypeptide containing the amino acid sequence of SEQ ID NO: 1, comprising (1) amino acid residues 81 (Met) to 92 (Phe) of SEQ ID NO: 1 or (2) amino acid residues 124 (Val) to 131 (Phe) of SEQ ID NO: 1, its amide or ester, or a salt thereof; (ii) contacting (a) the isolated protein or a salt thereof with (b) a polypeptide comprising (1) amino acid residues 81 (Met) to 92 (Phe) of SEQ ID NO: 1 or (2) amino acid residues 124 (Val) to 131 (Phe) of SEQ ID NO: 1, its amide or ester, or a salt thereof, and measuring binding activity between the isolated protein or a salt thereof and the polypeptide or its amide or ester, or a salt thereof; (iii) contacting (a) the isolated protein or a salt thereof and a test compound with (b) a polypeptide comprising (1) amino acid residues 81 (Met) to 92 (Phe) of SEQ ID NO: 1 or (2) amino acid residues 124 (Val) to 131 (Phe) of SEQ ID NO: 1, its amide or ester, or a salt thereof, and measuring binding activity between the isolated protein or a salt thereof and the polypeptide or its amide or ester, or a salt thereof; and (iv) comparing the activity of case (ii) with the activity of case (iii).