Autophagosomes

Definition

Autophagosomes are double-membraned vesicles that contain cellular material slated to be degraded by autophagy. An isolation membrane or phagophore forms near autophagic cargo and expands until it encloses the cargo. Autophagosome formation depends on the activity of a type III PI3K lipid kinase.

Latest Research and Reviews

  • Research |

    De Leo et al. identify a lysosomal response to autophagic cargo during lysosome–autophagosome fusion that involves TLR9 activation and OCRL recruitment, and leads to a regulated local increase in PtdIns(4,5)P2, which is necessary for a normal autophagic flux.

    • Maria Giovanna De Leo
    • , Leopoldo Staiano
    • , Mariella Vicinanza
    • , Alessandro Luciani
    • , Annamaria Carissimo
    • , Margherita Mutarelli
    • , Antonella Di Campli
    • , Elena Polishchuk
    • , Giuseppe Di Tullio
    • , Valentina Morra
    • , Elena Levtchenko
    • , Francesca Oltrabella
    • , Tobias Starborg
    • , Michele Santoro
    • , Diego di Bernardo
    • , Olivier Devuyst
    • , Martin Lowe
    • , Diego L. Medina
    • , Andrea Ballabio
    •  & Maria Antonietta De Matteis
    Nature Cell Biology 18, 839–850
  • Research | | open

    Autophagy requires transport of autophagosomes to the perinuclear region. Here, the authors show that ORP1L localizes to autophagosomes and mediates formation of ER contact sites that prevent autophagosome transport and fusion with endocytic vesicles when cholesterol levels are low.

    • Ruud H. Wijdeven
    • , Hans Janssen
    • , Leila Nahidiazar
    • , Lennert Janssen
    • , Kees Jalink
    • , Ilana Berlin
    •  & Jacques Neefjes
  • Research | | open

    Autophagy is a catabolic process whereby cellular components are degraded by the autophagosome, but the role of the actin cytoskeleton is not clear. Here Coutts and La Thangue show that the actin nucleator JMY is recruited to the autophagosome via binding LC3, and promotes actin nucleation that is required for autophagosome maturation.

    • Amanda S. Coutts
    •  & Nicholas B. La Thangue
  • Research |

    The Cvt pathway in yeast operates constitutively, but the mechanism by which non-cargo material is excluded from the vacuole is incompletely defined. Martens and colleagues show that cargo binding to the cargo receptor Atg19 exposes further Atg8 binding sites on the receptor, which draws the isolation membrane around the autophagic cargo and prevents inclusion of non-cargo material in autophagosomes.

    • Justyna Sawa-Makarska
    • , Christine Abert
    • , Julia Romanov
    • , Bettina Zens
    • , Iosune Ibiricu
    •  & Sascha Martens
    Nature Cell Biology 16, 425–433
  • Reviews |

    Autophagosome biogenesis starts at the isolation membrane (also called the phagophore). Our understanding of the molecular processes that initiate the isolation membrane, the membrane sources from which this membrane originates and how it is expanded to the autophagosome membrane by autophagy-related (ATG) proteins and the vesicular trafficking machinery, is increasing.

    • Christopher A. Lamb
    • , Tamotsu Yoshimori
    •  & Sharon A. Tooze
  • Research | | open

    BafilomycinA1 is an autophagy inhibitor, presumably owing to its blocking effect on the lysosomal proton pump V-ATPase. Here the authors show that V-ATPase-deficient lysosomes can still fuse with autophagosomes, showing that lysosomal acidification and fusion are two separable, independent events.

    • Caroline Mauvezin
    • , Péter Nagy
    • , Gábor Juhász
    •  & Thomas P. Neufeld

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