Molecular machinery of autophagosome formation in yeast, Saccharomyces cerevisiae

Abstract 

Autophagy is a degradation process accompanied by dynamic membrane organization. In the yeast, Saccharomyces cerevisiae, about 30 ATG (autophagy-related) genes have been identified as important genes for autophagy. Among them, 17 are indispensable for formation of the autophagosome, an organelle enclosed by a double lipid bilayer during starvation-induced autophagy. Recently, a central structure for autophagosome generation, termed the pre-autophagosomal structure, was identified. Despite intensive study, many questions regarding the mechanisms underlying autophagosome formation remain unanswered. In this review, we will give an overview of recent studies on the mechanisms of autophagosome formation and discuss these unresolved questions.

Abbreviations: AS-PI3K, autophagy-specific phosphatidylinositol 3-kinase, ATG genes, autophagy-related genes, COP, coatmer, Cvt, cytoplasm-to-vacuole targeting, ER, endoplasmic reticulum, GFP, green fluorescent protein, IM, isolation membrane, NSF, N-ethylmaleimide-sensitive fusion protein, PAS, pre-autophagosomal structure, PE, phosphatidylethanolamine, PtdIns(3)P, phosphatidylinositol 3-phosphate, PtdIns(3,5)P₂, phosphatidylinositol 3,5-bisphosphate, SNAP, soluble NSF attachment protein, SNARE, SNAP receptor

Keywords: Autophagy, Autophagosome, ATG genes, Pre-autophagosomal structure, Nutrient starvation