MSH (melanocyte-stimulating hormone), produced by the pituitary gland, regulates the pigmentation of the skin by increasing melanin production in melanocytes. Gamma-MSH peptides contain a core 7-amino-acid residue sequence similar to ACTH(4-10). Gamma-3 MSH is a 15-aa C-term extension of the Gamma-2 MSH 12-aa peptide. Gamma-3 MSH corresponds to aa 77-102 of corticotropin precursor (pro-opiomelanocortin, POMC). Gamma-3 MSH binds to the melanocortin-3 receptor (MC3-R).Human: H-Tyr-Val-Met-Gly-His-Phe-Arg-Trp-Asp-Arg-Phe-Gly-Arg-Arg-Asn-Ser-Ser-Ser-Ser-Gly-Ser-Ser-Gly-Ala-Gly-Gln-OH or H-YVMGHFRWDRFGRRNSSSSGSSGAGQ-OH