Melanocortin Receptor 4 (MC4R)

Melanocortin receptor 4 (MC4R) is a G protein-coupled receptor primarily expressed in the central nervous system, especially in the paraventricular nucleus of the hypothalamus. MC4R plays a crucial role in regulating energy homeostasis, feeding behavior, metabolism, sexual function, and body weight. Mutations or dysfunctions in MC4R are linked with severe early-onset obesity. Pharmacological targeting includes peptide/small molecule agonists aimed at restoring or modulating receptor activity for anti-obesity therapies.

Agonists bind to MC4R, activating GαS proteins and increasing cAMP production. Some small molecules act as pharmacological chaperones, rescuing misfolded mutant receptors.