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Updated: Dec 18, 2025

Study of Protein-protein Interactions in Autophagy Research
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Study of Protein-protein Interactions in Autophagy Research

Published on: September 9, 2017

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ULK complex organization in autophagy by a C-shaped FIP200 N-terminal domain dimer

Xiaoshan Shi1, Adam L Yokom1, Chunxin Wang2

  • 1Department of Molecular and Cell Biology and California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA.

The Journal of Cell Biology
|June 10, 2020
PubMed

Insights

The ULK complex, crucial for autophagy, involves ULK1/2, FIP200, ATG13, and ATG101. Researchers mapped their interactions, revealing FIP200

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Structural Biology

Background:

  • The ULK complex is essential for initiating autophagy, a fundamental cellular process.
  • Understanding the structural organization of the ULK complex is key to elucidating autophagy regulation.

Purpose of the Study:

  • To map the molecular interactions within the human ULK complex.
  • To determine the quaternary structure of the ULK complex and its subunits.

Main Methods:

  • Hydrogen-deuterium exchange mass spectrometry (HDX-MS) to map protein interactions.
  • Negative stain electron microscopy (EM) and multiangle light scattering (MALS) to assess complex assembly.
  • Cryo-electron microscopy (Cryo-EM) to resolve structural details.

Main Results:

  • FIP200 forms a dimer, interacting with ATG13 via its N-terminal domain (NTD).
  • The FIP200 NTD undergoes a conformational change upon ATG13 binding, adopting a C-shape.
  • ULK1 interacts with the FIP200 dimer, while the ATG13:ATG101 dimer does not directly contact FIP200.

Conclusions:

  • The study reveals the structural architecture of the ULK complex, highlighting key subunit interactions.
  • Structural similarities between FIP200 NTD and TBK1 suggest evolutionary links between autophagy and immunity kinases.

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