The molecular evolution of teleost olfactory receptor gene families.

摘要: Four olfactory receptor gene families, all of them G protein-coupled receptors, have been identified and characterized in mammals – the odorant (OR), vomeronasal (V1R V2R) trace amine-associated (TAARs) receptors. Much less attention has directed towards non-mammalian members these families. Since a hallmark mammalian receptors is their remarkable species specificity, an evaluation instructive both for comparative purposes its own right. In this review I compiled results currently available four families discuss phylogenomic properties relation to counterparts. Representatives are found cartilaginous fish and/or jawless fish, allowing minimal estimate evolutionary origin as preceding segregation between bony or respectively. Gene repertoires teleost smaller size (OR, ORA), comparable (olfC), even larger (TAAR) than corresponding repertoires. Despite repertoire size, OR ORA show much divergence Evolutionary rates vary greatly with evidence positive selection genes, whereas ora genes subject strong negative selection, fact being conserved among investigated. With one exception, ligands unknown any so considerable knowledge about odor responses epithelium bulb can only be linked indirectly