title: Cheating on ubiquitin with Atg8.
abstract: Macroautophagy sequesters superflous cytosol and organelles into double-membraned autophagosomes. Over 30 autophagy-related (ATG) genes have been identified without elucidating the molecular details of autophagosome biogenesis. All proposed models for autophagosome formation require membrane fusion events (Fig. 1). Previous studies assumed that the autophagic machinery mediates these membrane fusions in a SNARE-independent manner and identified the ubiquitin-like protein Atg8 as a key component especially for elongation of the forming autophagosome. However, if and how Atg8 mediates membrane fusion and why a ubiquitin-like protein is needed for autophagosome biogenesis remained open questions. Since nuclear envelope growth and fusion of Golgi fragments are topologically similar to autophagosome formation and depend on the AAA (+) ATPase p97/VCP and p47 we analyzed the involvement of their yeast homologues Cdc48 and Shp1 in macroautophagy.
authors.affiliation: Department Biochemistry II, Georg-August University, Goettingen, Germany.
authors.forename: Roswitha
authors.initials: R
authors.lastname: Krick
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bremer
authors.forename: Evelyn
authors.initials: E
authors.lastname: Welter
authors.forename: Eeva-Liisa
authors.initials: EL
authors.lastname: Eskelinen
authors.forename: Michael
authors.initials: M
authors.lastname: Thumm
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001343:Autophagy; D000071190:Autophagy-Related Protein 8 Family; D018797:Cell Cycle Proteins / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008954:Models, Biological; D010588:Phagosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism*; D000074405:Valosin Containing Protein
chemical_list: C113757:ATG8 protein, S cerevisiae; D000071190:Autophagy-Related Protein 8 Family; D018797:Cell Cycle Proteins; D008869:Microtubule-Associated Proteins; D029701:Saccharomyces cerevisiae Proteins; D025801:Ubiquitin; D000251:Adenosine Triphosphatases; C000614177:CDC48 protein, S cerevisiae; D000074405:Valosin Containing Protein