Schematic representation of the cleavage of pituitary proopiomelanocortin (POMC) by prohormone convertase (PC) enzymes 1 and 2. Generated peptides include α-, β-, and γ-melanocyte–stimulating hormone (MSH), β- and γ- lipotropic hormone (LPH), adrenocorticotropic hormone (ACTH), β-endorphin (β-END), and the amino-terminal (NT), joining (JP), and CLIP peptides. Note that the release of γ-MSH requires a cleavage by PC2 at both ends.