Olfactory receptor 51B5 (OR51B5)

Olfactory receptor 51B5 (OR51B5) is a member of the olfactory receptor family, encoded by a single-exon gene on chromosome 11 (11p15.4). Like other olfactory receptors, it possesses a seven-transmembrane domain characteristic of GPCRs and mediates signal transduction by interacting with odorant molecules, activating intracellular G protein signaling cascades. While primarily expressed in the olfactory epithelium, OR51B5 is also expressed in other tissues, including skin and certain cancers. Recent studies highlight its additional function as a tumor suppressor in esophageal cancer: transcriptional silencing of OR51B5 by chromatin modification leads to enhanced N-Ras activity and tumor cell proliferation, while its activation increases intracellular Ca²⁺ and suppresses malignancy, indicating relevance as a novel therapeutic target and prognostic marker in cancer. OR51B5 also participates in keratinocyte migration, relevant to wound healing.

Other names

OR51B5HOR5'Beta5OR11-37Odorant receptor HOR5'beta5olfactory receptor family 51 subfamily B member 5

For putative ligands (isononyl alcohol): activation of OR51B5 increases intracellular Ca²⁺ signaling and reduces N-Ras expression, inhibiting cell proliferation and metastasis; G protein–mediated signal transduction.