小G蛋白Rab5的研究进展

Research progress on small G protein Rab5

小GTP酶Rab5是细胞内部各类膜组分(membrane component)运输的关键调节因子。Rab5在无活性的GDP结合形式和有活性的GTP结合形式之间循环。不同状态的Rab5通过募集不同的下游效应物,调控囊泡的出芽、锚定和融合运输。Rab5除了能够调节早期胞内体(early endosome)的融合,它还调节细胞自噬、线粒体的稳态、染色质的排列整合、细胞的迁移以及能量代谢等。此外,Rab5与肿瘤、阿尔兹海默症及亨廷顿病也有着非常密切的关系。本文结合近几年Rab5的最新研究进展作一综述。

The small GTPase Rab5 is a key regulator of the transport of various membrane components in cells.Rab5 switches between an inactive GDP-binding state and an active GTP-binding state.Different states of Rab5 recruit different effectors that allow for their various roles in vesicle budding,vesicle tethering,and fusion.In addition to regulating the fusion of early endosomes,recent studies reveal the function of Rab5 in regulating autophagy,mitochondrial homeostasis,chromatin alignment,cell migration,and energy metabolism.Moreover,there is evidence showing that the aberrant activation and mislocalization of Rab5 might contribute to tumors,Alzheimer’s disease and Huntington’s disease.This review focuses on the recent advances on the functions of Rab5.