Agouti signalling peptide

agouti signalling protein, nonagouti homolog (mouse)
NMR structure family of Agouti Signalling Protein, C-terminal knotting domain. PDB entry 1y7k
Identifiers
Symbol	ASIP
Alt. symbols	AGTIL
Entrez	434
HUGO	745
OMIM	600201
RefSeq	NM_001672
UniProt	P42127
Other data
Locus	Chr. 20 q11.2-q12

Agouti signalling peptide, a product of the Agouti gene, is a peptide consisting of 131 amino acids. Its discovery was published in 1994 in the scientific journal Nature where its functional properties were described. It acts as an inverse agonist at melanocortin receptors, to be specific MC1. It is produced by the Agouti gene ASIP.

In mice, the agouti gene encodes a paracrine signalling molecule that causes hair follicle melanocytes to synthesize the yellow pigment pheomelanin instead of the black or brown pigment eumelanin. Pleiotropic effects of constitutive expression of the mouse gene include adult-onset obesity, increased tumor susceptibility, and premature infertility. This gene is highly similar to the mouse gene and encodes a secreted protein that may (1) affect the quality of hair pigmentation, (2) act as an inverse agonist of alpha-melanocyte-stimulating hormone, (3) play a role in neuroendocrine aspects of melanocortin action, and (4) have a functional role in regulating lipid metabolism in adipocytes.

Agouti signalling peptide adopts an inhibitor cystine knot motif. Along with the homologous Agouti-related peptide, these are the only known mammalian proteins to adopt this fold.

This article incorporates text from the United States National Library of Medicine, which is in the public domain.