A secreted protein of approximately 131 amino acids (depending on species) that regulates the synthesis of eumelanin (brown/black) pigments in MELANOCYTES. Agouti protein antagonizes the signaling of MELANOCORTIN RECEPTORS and has wide distribution including ADIPOSE TISSUE; GONADS; and HEART. Its overexpression in agouti mice results in uniform yellow coat color, OBESITY, and metabolic defects similar to type II diabetes in humans.

Synonyms: 0, Agouti Protein, Agouti Signaling Protein, Agouti Switch Protein, ASIP Protein