Melatonin receptor 1B (MTNR1B)

Melatonin receptor 1B is a high-affinity G protein-coupled membrane receptor primarily responsive to the neurohormone melatonin. Encoded by the *MTNR1B* gene, it plays key roles in regulating circadian rhythms, reproductive physiology, bone formation, and insulin secretion. The receptor is expressed mainly in brain regions such as the retina but also found on pancreatic beta cells where it influences glucose metabolism. Genetic variants affecting its function have been linked to an elevated risk of developing type 2 diabetes due to altered insulin secretion dynamics. As a drug target, both selective agonists and antagonists have been developed—some with high specificity over related receptors—making it an important focus for therapies addressing sleep disorders, metabolic diseases like diabetes mellitus type II, mood disturbances, and possibly certain cancers.

Other names

MT2Mel-1B-RMel1b receptorMT2R

Drugs targeting this molecule typically act by: - Agonism or partial agonism at the melatonin binding site, mimicking or enhancing endogenous melatonin signaling to regulate circadian rhythms or metabolic processes. - Antagonists block the action of endogenous melatonin at this site, potentially modulating sleep-wake cycles or glucose metabolism.