《生物化學與分子生物學》 一、膜受體的分類

隨著越來越多的膜表面受體被純化，其結構及轉導信號的方式逐步得以闡明。目前，按照受體的結構及其作用方式可將其分為三大類。這三大類受體在配體種類、受體的一般結構和功能及細胞對之發(fā)生反應的方式上有所不同，見表21－2。

Table 21－2　Classification of MembraneReceptors:Characteristics of Three Groups of Receptors

CharacteristicsIon Channel ReceptorsG-Protein-Linked receptorsRecetpors with a Single Transmembrane DomainEndogenous ligandsNeurotransmitterNeurotransmitterGrowth factor hormoneHormoneCytokineAuloacoidChemotactic factorExogenous stimulantStructureOligomer with a poreProbably monomerMonomer of oligonerwith (±）catalyticdomainNumber of transmemFour per subunitSevenOne per subunitbane segmentsFunctionIon channelActivation of G proteinsTyrosine kinaseGiuanylate cyclase(?)Cellular responsesDepolarization orDepolarization orRegulation of functionhyperpolarizationhyperpolarizationand expression ofRegulation of functionproteinsand expression ofProliferation orproteinsdifferentiation