title: Localization of Atg3 to autophagy-related membranes and its enhancement by the Atg8-family interacting motif to promote expansion of the membranes.
abstract: The E2 enzyme Atg3 conjugates the ubiquitin-like protein Atg8 to phosphatidylethanolamine (PE) to drive autophagosome formation in Saccharomyces cerevisiae. In this study, we show that Atg3 localizes to the pre-autophagosomal structure (PAS) and the isolation membrane (IM), providing crucial evidence that Atg8-PE conjugates are produced on these structures. We also find that mutations in the Atg8-family interacting motif (AIM) of Atg3 significantly impairs the PAS/IM localization of Atg3, resulting in inefficient IM expansion. It is suggested that the AIM-mediated PAS/IM localization of Atg3 facilitates membrane expansion in these structures probably by ensuring active production of Atg8-PE on the membranes.
authors: Frontier Research Center, Tokyo Institute of Technology, Yokohama 226-8503, Japan.
authors: Machiko
authors: M
authors: Sakoh-Nakatogawa
authors: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8503, Japan; CREST, Japan Science and Technology Agency, Saitama 332-0012, Japan.
authors: Hiromi
authors: H
authors: Kirisako
authors: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8503, Japan; CREST, Japan Science and Technology Agency, Saitama 332-0012, Japan. Electronic address: hnakatogawa@bio.titech.ac.jp.
authors: Hitoshi
authors: H
authors: Nakatogawa
authors: Frontier Research Center, Tokyo Institute of Technology, Yokohama 226-8503, Japan. Electronic address: yohsumi@iri.titech.ac.jp.
authors: Yoshinori
authors: Y
authors: Ohsumi
mesh_terms: D001343:Autophagy; D000071190:Autophagy-Related Protein 8 Family; D000071183:Autophagy-Related Proteins; D002462:Cell Membrane / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000737:chemistry; D010714:Phosphatidylethanolamines / Q000378:metabolism; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism*
chemical_list: C113757:ATG8 protein, S cerevisiae; D000071190:Autophagy-Related Protein 8 Family; D000071183:Autophagy-Related Proteins; D008869:Microtubule-Associated Proteins; D010714:Phosphatidylethanolamines; D029701:Saccharomyces cerevisiae Proteins; C483858:phosphatidylethanolamine; D044763:Ubiquitin-Conjugating Enzymes; C104235:ATG3 protein, S cerevisiae
keywords: Autophagosome; E2 enzyme; Lipidation; Ubiquitin-like protein; Yeast