The Ligand:GPCR:G12/13 complex dissociates

The classical view of G-protein signalling is that the G-protein alpha subunit dissociates from the beta:gamma dimer. Activated G alpha (12/13) and the beta:gamma dimer then participate in separate signaling cascades. Although G protein dissociation has been contested (e.g. Bassi et al. 1996), recent in vivo experiments have demonstrated that dissociation does occur, though possibly not to completion (Lambert 2008).

经典的G蛋白信号传导观点认为，G蛋白的α亚基会从β:γ二聚体中解离。随后，激活的Gα（12/13）以及β:γ二聚体分别参与独立的信号级联反应。尽管G蛋白的解离现象曾受到争议（例如，Bassi等人，1996年），但近期的体内实验已证实，解离现象确实存在，尽管可能并非完全解离（Lambert，2008年）。