Rens-Domiano S, Hamm H E
Department of Physiology and Biophysics, University of Illinois at Chicago, College of Medicine 60612, USA.
FASEB J. 1995 Aug;9(11):1059-66. doi: 10.1096/fasebj.9.11.7649405.
Heterotrimeric GTP-binding proteins (G-proteins) are a critical component of signal transduction pathways that carry information received at the cell surface to the appropriate cellular effector system, ultimately achieving a specific cellular response. Heterotrimeric G-proteins consist of an alpha-subunit, which contains the guanine nucleotide binding site and intrinsic GTPase activity, and an inseparable beta gamma-subunit complex. G-proteins act to define the specificity by which a receptor regulates a particular intracellular signaling system, as well as to regulate the duration of the signal. A great deal of structural and functional insight into how G-protein-mediated signal transduction occurs has recently been achieved. This review will discuss the structural features of G-proteins, as well as detail the mechanism by which G-proteins interact with receptors and effectors.
异源三聚体GTP结合蛋白（G蛋白）是信号转导途径的关键组成部分，该途径将在细胞表面接收到的信息传递到适当的细胞效应系统，最终实现特定的细胞反应。异源三聚体G蛋白由一个α亚基和一个不可分割的βγ亚基复合物组成，α亚基包含鸟嘌呤核苷酸结合位点和内在的GTP酶活性。G蛋白的作用是确定受体调节特定细胞内信号系统的特异性，以及调节信号的持续时间。最近，人们对G蛋白介导的信号转导如何发生有了大量的结构和功能方面的深入了解。本综述将讨论G蛋白的结构特征，并详细阐述G蛋白与受体和效应器相互作用的机制。
