title: Small GTPase proteins in macroautophagy.
abstract: Macroautophagy, a highly conserved process in eukaryotic cells, is initiated in response to stress, especially nutrient starvation. Macroautophagy helps cells survive by engulfing proteins and organelles into an unusual double-membraned structure called the autophagosome, which then fuses with the lysosome. Upon degradation of the engulfed contents, the building blocks are recycled for synthesis of new macromolecules. Recent work has demonstrated that construction of the autophagosome requires a variety of small GTPases in variations of their normal roles in membrane traffic. In this Commentary, we review our own recent findings with respect to 2 different GTPases, Arl1, a member of the Arf/Arl/Sar family, and Ypt6, a member of the Rab family, in the yeast S. cerevisiae in light of other information from the literature and discuss future directions for further discerning the roles of small GTPases in autophagy.
authors.affiliation: a Department of Biology , Georgetown University , Washington, DC , USA.
authors.forename: Shu
authors.initials: S
authors.lastname: Yang
authors.affiliation: a Department of Biology , Georgetown University , Washington, DC , USA.
authors.forename: Anne
authors.identifier: 0000-0002-0144-8515
authors.initials: A
authors.lastname: Rosenwald
mesh_terms: D000818:Animals; D001343:Autophagy; D020558:GTP Phosphohydrolases / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology
chemical_list: D020558:GTP Phosphohydrolases
keywords: Arl1; GTPase-activating protein (GAP); Saccharomyces cerevisiae; Ypt6; autophagosome; guanine nucleotide exchange factor (GEF); macroautophagy; membrane traffic