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

ABSTRACT: 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 aut

SUBMITTER: Chen M 

PROVIDER: S-EPMC12440827 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature