Melanocortin Receptor 3 (MC3R) is one of five members of the melanocortin receptor family, which belongs to the 7-transmembrane domain, G protein-coupled receptor (GPCR) superfamily.nThe ligands of these receptors, the melanocortins, are a group of structurally-related peptides comprising the α-, ß-, and γ-melanocyte-stimulating hormone (α-, ß-, γ-MSH) and the adrenocorticotropic hormone (ACTH), all of which are derived from post-translational processing of a common precursor peptide, proopiomelanocortin (POMC).