Patent ID: 7294475

Claim:
A method for screening a compound or its salt that inhibits the binding of a protein comprising the amino acid sequence of SEQ ID NO: 1, a partial peptide or a salt thereof, to insulin-responsive aminopeptidase (IRAP) or glucose transporter 4 (GLUT4), which comprises: (i) contacting (a) the protein comprising the amino acid sequence of SEQ ID NO: 1, its partial peptide comprising the amino acid numbers 977 th to 1190 th in SEQ ID NO: 1, or a salt thereof with (b) IRAP, a cytoplasmic side domain of IRAP comprising the amino acid sequence of SEQ ID NO: 11 or the amino acid numbers 55 th to 82 nd of SEQ ID NO: 11, GLUT4, a domain of GLUT4 in the cytoplasm comprising the amino acid sequence of SEQ ID NO: 13, or a salt thereof, and measuring the binding activity between the protein, its partial peptide, or a salt thereof and IRAP, the cytoplasmic side domain of IRAP, GLUT4, the domain of GLUT4 in the cytoplasm, or a salt thereof; (ii) contacting (a) the protein comprising the amino acid sequence of SEQ ID NO: 1, its partial peptide comprising the amino acid numbers 977 th to 1190 th in SEQ ID NO: 1, or a salt thereof and a test compound with (b) IRAP, a cytoplasmic side domain of IRAP comprising the amino acid sequence of SEQ ID NO: 11 or the amino acid numbers 55 th to 82 nd of SEQ ID NO: 11, GLUT4, a domain of GLUT4 in the cytoplasm comprising the amino acid sequence of SEQ ID NO: 13, or a salt thereof, and measuring the binding activity between the protein, its partial peptide, or a salt thereof and IRAP the cytoplasmic side domain of IRAP, GLUT4, the domain of GLUT4 in the cytoplasm, or a salt thereof; and (iii) comparing the activity of case (i) with the activity of case (ii)using said protein.