Gq alpha:G beta:G gamma dissociates to Gq alpha:GTP and G beta:G gamma

In the non-activated state heterotrimeric G proteins exist at membranes as heterotrimeric complexes of alpha, beta, and gamma subunits, with the alpha subunit bound to GDP. Upon activation by a receptor coupled to the heterotrimer, exchange of GDP for GTP by the Gq alpha subunit causes the alpha subunit to lose affinity for the beta and gamma subunits. The alpha subunit with bound GTP then dissociates from the beta and gamma subunits.

在非激活状态下，异源三聚体G蛋白以α、β和γ亚基组成的异源三聚体复合物的形式存在于细胞膜上，其中α亚基与GDP结合。当与异源三聚体偶联的受体被激活后，Gq α亚基中的GDP与GTP的交换导致α亚基对β和γ亚基的亲和力降低。随后，与GTP结合的α亚基从β和γ亚基上解离。