G蛋白信号调节因子的结构分类和功能

G蛋白信号调节因子是能够直接与激活的Gα亚基结合,显著刺激Gα亚基上的GTP酶活性,加速GTP水解,从而灭活或终止G蛋白信号的一组分子大小各异的多功能蛋白质家族。它们都共同拥有一个130个氨基酸的保守的RGS结构域,其功能是结合激活的Gα亚基,负调节G蛋白信号。许多RGS蛋白还拥有非RGS结构域,能够结合其它信号蛋白,从而整合和调节G蛋白信号之间以及G蛋白和其它信号系统之间的关系。

The structure, classification and function of RGS proteins

Regulators of G protein signaling (RGS) are a family of highly diverse, multifunctional signaling proteins that bind directly to activated Galpha subunits and markedly stimulates the GTPase activity of Galpha subunits leading to their deactivation and termination of downstream signals. RGS family members share a conserved 130-amino acid core domain which is responsible for binding Galpha subunits and negatively regulate G protein signal. Many RGS proteins possess additional non RGS domains and motifs. The non RGS domains are involved to integrate different G protein signaling pathways and as a saffolding protein that links G protein to related signaling proteins.