NMUR1

NMUR1, short for neuromedin U receptor 1, is a G protein-coupled receptor that binds the neuropeptide neuromedin U (NMU). Together with NMUR2, NMUR1 forms the receptor system for NMU, which is involved in modulating feeding, energy balance, and autonomic functions. The NMUR1 gene encodes a seven-transmembrane receptor that is activated by neuromedin U, with the principal ligands being NMU-25 and NMU-8.

Signaling through NMUR1 is primarily mediated by Gq/11 proteins, leading to activation of phospholipase C and mobilization of intracellular calcium; other signaling pathways may also contribute. NMUR1 exhibits broad expression in peripheral tissues, including parts of the gastrointestinal tract, adipose tissue, pancreas, and cardiovascular system, whereas NMUR2 is more abundantly expressed in the brain. The distinct tissue distribution supports roles for NMUR1 in peripheral regulation of gut function, metabolism, and autonomic responses, complementing the central actions of NMUR2.

In physiological studies, NMUR1 signaling has been linked to regulation of feeding behavior, energy homeostasis, and stress responses in animal models, with indications that it may influence gut motility and endocrine secretion. The precise relevance to human physiology remains under investigation. From a clinical perspective, the involvement of NMUR1 in metabolic and autonomic processes in animals has made it a potential target for obesity and metabolic disorder therapies, though no NMUR1-targeted drugs are approved and human data are still emerging.