OR6A2

Odorant receptor for medium-chain aliphatic aldehydes, such as octanal, nonanal and trans-2-decenal. Activated by aliphatic aldehydes with chains ranging from 5 to 11 carbon atoms, with preference for octanal (C8). Ligand-binding involves the formation of a reversible covalent Schiff base linkage with the aldehyde, causing a conformation change that triggers signaling via G(s)-class of G alpha proteins (GNAL/G(olf) or GNAS/G(s)). In olfactory epithelium, couples to GNAL/G(olf), mediating activation of adenylate cyclase activity and increased production of cAMP, initiating a neuronal response that triggers the perception of a smell. Beyond its role in olfaction, also acts as a regulator of inflammation. In macrophages, activation by octanal, a product of lipid peroxidation during oxidative stress, triggers a signaling that promotes activation of the NLRP3 inflammasome, leading to the production of pro-inflammatory cytokines, such as IL1B, exacerbating inflammatory processes in vascular macrophages and contributing to atherosclerosis. Outside of the olfactory system, in tissues lacking GNAL/G(olf), couples to GNAS/G(s), promoting activation of adenylate cyclase activity and production of cAMP..

Function from UniProtKB (O95222), read 2026-09-23. CC BY 4.0.