Three-step docking by WIPI2, ATG16L1 and ATG3 delivers LC3 to the phagophore

Output Details

Preprint July 19, 2023

Published February 6, 2024

The covalent attachment of ubiquitin-like LC3 proteins (microtubule-associated proteins 1A/1B light chain 3) prepares the autophagic membrane for cargo recruitment. We resolve key steps in LC3 lipidation by combining molecular dynamics simulations and experiments in vitro and in cellulo. We show how the E3-like ligase autophagy- related 12 (ATG12)–ATG5-ATG16L1 in complex with the E2-like conjugase ATG3 docks LC3 onto the membrane in three steps by (i) the phosphatidylinositol 3-phosphate effector protein WD repeat domain phosphoinositide- interacting protein 2 (WIPI2), (ii) helix α2 of ATG16L1, and (iii) a membrane-interacting surface of ATG3. Phospha- tidylethanolamine (PE) lipids concentrate in a region around the thioester bond between ATG3 and LC3, highlighting residues with a possible role in the catalytic transfer of LC3 to PE, including two conserved histi- dines. In a near-complete pathway from the initial membrane recruitment to the LC3 lipidation reaction, the three-step targeting of the ATG12–ATG5-ATG16L1 machinery establishes a high level of regulatory control.
Identifier (DOI)
10.1126/sciadv.adj8027
Tags
  • ATG12-5-16L1
  • ATG3 (E2-like enzyme)
  • Cell biology
  • In Vitro
  • LC3
  • LC3 lipidation
  • Lipid bilayers
  • Lipids
  • Molecular Dynamics simulation (MD)
  • Original Research
  • Recombinant

Meet the Authors

  • User avatar fallback logo

    Shanlin Rao, PhD

    Key Personnel: Team Hurley

    Max Planck Institute of Biophysics

  • User avatar fallback logo

    Marvin Skulsuppaisarn

  • Lisa Strong, BSc

    Key Personnel: Team Hurley

    University of California, Berkeley

  • User avatar fallback logo

    Xuefeng Ren, PhD

    Key Personnel: Team Hurley

    University of California, Berkeley

  • Michael Lazarou, PhD

    Co-PI (Core Leadership): Team Hurley

    Monash University

  • James Hurley

    Lead PI (Core Leadership): Team Hurley

    University of California, Berkeley

  • Gerhard Hummer, PhD

    Collaborating PI: Team Hurley

    Max Planck Institute of Biophysics