Roles of Rab proteins in vesicle transport

Abstract

Rab proteins are a part of a conserved small GTPase family in eukaryotes that are widely expressed in cells, and their activities are strictly regulated within the cell: the transition between the active Rab-GTP and inactive Rab-GDP forms is regulated by guanine nucleotide exchange factors (GEFs) and GTPase-activated proteins (GAPs). Functioning as important molecular switches in vesicle transport, Rab proteins interact with several different downstream effector molecules that are involved in cargo selection from the donor membrane, bud development, movement along the cytoskeleton, and anchor of the vesicles to the receptor membrane. In addition, the impaired roles of Rab proteins and disturbed vesicle trafficking caused by abnormal Rab proteins may lead to various diseases, including cancer and neurodegenerative and immune diseases. This article will review the recent research progress on Rab proteins, molecular mechanisms involved in vesicle trafficking, regulation of the Rab protein cycle, and diseases caused by abnormal vesicle transport.