title: Impairment of starvation-induced and constitutive autophagy in Atg7-deficient mice.
abstract: Autophagy is a membrane-trafficking mechanism that delivers cytoplasmic constituents into the lysosome/vacuole for bulk protein degradation. This mechanism is involved in the preservation of nutrients under starvation condition as well as the normal turnover of cytoplasmic component. Aberrant autophagy has been reported in several neurodegenerative disorders, hepatitis, and myopathies. Here, we generated conditional knockout mice of Atg7, an essential gene for autophagy in yeast. Atg7 was essential for ATG conjugation systems and autophagosome formation, amino acid supply in neonates, and starvation-induced bulk degradation of proteins and organelles in mice. Furthermore, Atg7 deficiency led to multiple cellular abnormalities, such as appearance of concentric membranous structure and deformed mitochondria, and accumulation of ubiquitin-positive aggregates. Our results indicate the important role of autophagy in starvation response and the quality control of proteins and organelles in quiescent cells.
authors.affiliation: Department of Molecular Oncology, Tokyo Metropolitan Institute of Medical Science, Bunkyo-ku, Tokyo 113-8613, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Komatsu
authors.forename: Satoshi
authors.initials: S
authors.lastname: Waguri
authors.forename: Takashi
authors.initials: T
authors.lastname: Ueno
authors.forename: Junichi
authors.initials: J
authors.lastname: Iwata
authors.forename: Shigeo
authors.initials: S
authors.lastname: Murata
authors.forename: Isei
authors.initials: I
authors.lastname: Tanida
authors.forename: Junji
authors.initials: J
authors.lastname: Ezaki
authors.forename: Noboru
authors.initials: N
authors.lastname: Mizushima
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ohsumi
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Uchiyama
authors.forename: Eiki
authors.initials: E
authors.lastname: Kominami
authors.forename: Keiji
authors.initials: K
authors.lastname: Tanaka
authors.forename: Tomoki
authors.initials: T
authors.lastname: Chiba
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001343:Autophagy / Q000235:genetics*; D000071193:Autophagy-Related Protein 7; D002460:Cell Line; D022781:Hepatocytes / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D006529:Hepatomegaly / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D002479:Inclusion Bodies / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D007425:Intracellular Membranes / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D008099:Liver / Q000002:abnormalities* / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D008928:Mitochondria / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D015388:Organelles / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D010641:Phenotype; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D013217:Starvation / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism
chemical_list: C114830:ATG7 protein, S cerevisiae; C502661:Atg7 protein, mouse; D008869:Microtubule-Associated Proteins; D029701:Saccharomyces cerevisiae Proteins; D025801:Ubiquitin; D000071193:Autophagy-Related Protein 7