The melanocortin receptor 2, MC2 receptor, is Gs-coupled GPCRs expressed in zona fasciculata of the adrenal cortex placental and stimulates production of cortisol. MC2 is a member of the rhodopsin family of 7-transmembrane and it's also known as the ACTH receptor or corticotropin receptor because it is specific for ACTH alone. Activation of the MC2 receptor initiates a cascade of events affecting multiple steps in corticoid steroidogenesis. Mutations in MC2 may result in familial glucocorticoid deficiency, a group of autosomal recessive disorders characterized by resistance to ACTH.