Bioamine receptors: evolutionary and functional variations of a structural leitmotiv.

摘要: Bioamines act as neurohormonal messengers through their binding to receptors which belong the largest membrane protein family known so far: seven spanning receptors. This class of transmits effect agonist intracellular effectors by interacting with an intermediary G-protein. The diversity receptor subtypes inside family, observed in many animal species, is result a long evolutionary process. tendency diversification depends upon gene duplications and continuous accumulation mutations. maintenance vital functions organisms, however, strictly requires enough structural conservation ensure functionality corresponding proteins. Both forces cooperate adaptation organisms changing environment. We have reviewed here main conformational functional constraints exerted on structure bioamine They are mainly transmembrane conformation receptors, ability bind ligands, interact G-proteins desensitize. molecular basis biochemical pharmacological differences used classify members also been examined. Interestingly, this classification very close that obtained phylogeny methods, elucidate relationships between However, latter allows accurately distinguish different (paralogous genes) species homologues (orthologous genes). In addition, calculation phylogenetical distances reveals two periods diversification: first one occurred before separation arthropods from vertebrates, Precambrian, corresponds appearance second one, about 400 million years ago, might accompany cephalization CNS vertebrates.