Structure and activation of the human autophagy-initiating ULK1C:PI3KC3-C1 supercomplex

Output Details

Preprint June 12, 2023

Published May 28, 2025

The Unc-51-like kinase protein kinase complex (ULK1C) is the most upstream and central player in the initiation of macroautophagy in mammals. Here, we determined the cryo-electron microscopy structure of the human ULK1C core at amino-acid-level resolution. We also determined a moderate-resolution structure of the ULK1C core in complex with another autophagy core complex, the class III phosphatidylinositol 3-OH kinase complex I (PI3KC3-C1). We show that the two complexes coassemble through extensive contacts between the FIP200 scaffold subunit of ULK1C and the VPS15, ATG14 and BECN1 subunits of PI3KC3-C1. The FIP200:ATG13:ULK1 core of ULK1C undergoes a rearrangement from 2:1:1 to 2:2:2 stoichiometry in the presence of PI3KC3-C1. This suggests a structural mechanism for the initiation of autophagy through formation of a ULK1C:PI3KC3-C1 supercomplex and dimerization of ULK1 on the FIP200 scaffold.
Tags
  • Autophagy
  • Cryo-EM
  • Original Research
  • PI3KC3-C1 complex
  • Structural biology

Meet the Authors

  • Minghao Chen, PhD

    Key Personnel: Team Hurley

    University of California, Berkeley

  • Thanh Nguyen, PhD

    Key Personnel: Team Hurley

    Walter and Eliza Hall Institute of Medical Research

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    Xuefeng Ren, PhD

    Key Personnel: Team Hurley

    University of California, Berkeley

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    Grace Khuu, BSc

    Key Personnel: Team Hurley

    Monash University

  • Annan (Zeke) Cook, BSc

    Key Personnel: Team Hurley

    University of California, Berkeley

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    Yuanchang Zhao

  • User avatar fallback logo

    Ahmet Yildiz

  • Michael Lazarou, PhD

    Co-PI (Core Leadership): Team Hurley

    Monash University

  • James Hurley

    Lead PI (Core Leadership): Team Hurley

    University of California, Berkeley