Motilin receptor
Protein-coding gene in the species Homo sapiens
From Wikipedia, the free encyclopedia
Motilin receptor is a G protein-coupled receptor (previously GPCR38)[3][4][5] that binds motilin.[6][7] It was first cloned in 1999 by Merck Laboratories.[8] and scientists have since been searching for compounds to modify its behavior.[9]
| MLNR | |||||||||||||||||||||||||||||||||||||||||||||||||||
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| Aliases | MLNR, GPR38, MTLR1, motilin receptor | ||||||||||||||||||||||||||||||||||||||||||||||||||
| External IDs | OMIM: 602885; HomoloGene: 74398; GeneCards: MLNR; OMA:MLNR - orthologs | ||||||||||||||||||||||||||||||||||||||||||||||||||
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The primary structure of the motilin receptor consists of 412 amino acids,[8] while its tertiary structure resembles a golf club.[10] The protein C-terminal protein protects from enzymatic degradation, while the N-terminal is essential for binding.[10]
Function
The primary function of the motilin receptor is to contract gastric smooth muscle during phase III of the migrating motor complex (MMC).[8] In this final phase of the MMC, N-type motilin receptors in the distal antral pump of the stomach are activated.[11] This causes contraction of the gastric smooth muscle, sieving food into the small intestine, and priming the stomach for the next meal.[12]
Motilin
Motilin is an intestinal peptide that stimulates the contraction of gastric smooth muscle via the motilin receptor.[8] It is produced by enteroendocrine cells in the proximal small intestine[3][13] and secreted cyclically.[14] Motilin mimetics could be used to increase gastric motility in patients with gastroparesis e.g., constipation-predominant irritable bowel syndrome.[15] However, none of the candidate drugs that have been tested so far have made it to market.[4][16]
