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Author Spotlight: A Selective Luciferase-Based Assay for Monitoring ATG4B 27 Activity in Cells
Published on: June 30, 2023
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Atg4 proteolytic activity can be inhibited by Atg1 phosphorylation
Jana Sánchez-Wandelmer1,2, Franziska Kriegenburg1,2, Sabrina Rohringer3
1Department of Cell Biology, University of Groningen, University Medical Center Groningen, A. Deusinglaan 1, 9713 AV, Groningen, The Netherlands.
Nature Communications
|August 20, 2017
Summary
Autophagosome formation relies on Atg8 protein conjugation. A novel finding shows Atg1 phosphorylation of Atg4 protease at the autophagosome site regulates this process, coordinating key steps in autophagosome biogenesis.
Area of Science:
- Cellular Biology
- Molecular Biology
- Autophagy Research
Background:
- Autophagosome biogenesis requires Atg8-like proteins conjugated to phosphatidylethanolamine.
- The cysteine protease Atg4 processes Atg8 for conjugation and deconjugation, but coordination is unclear.
Purpose of the Study:
- To elucidate the coordination mechanism between Atg8 conjugation and deconjugation by Atg4.
- To investigate the role of Atg1 in regulating Atg4 activity during autophagosome formation.
Main Methods:
- Investigated Atg4 activity regulation.
- Examined Atg1 phosphorylation of Atg4.
- Assessed Atg4 function at autophagosome biogenesis sites.
Main Results:
- Phosphorylation by Atg1 inhibits Atg4 protease activity.
- This inhibitory phosphorylation occurs specifically at autophagosome biogenesis sites.
- A model is proposed where Atg1 phosphorylation protects the Atg8-phosphatidylethanolamine pool.
Conclusions:
- Atg1-mediated phosphorylation of Atg4 is a key regulatory step coordinating Atg8 processing for autophagosome formation.
- This regulation ensures the availability of Atg8-phosphatidylethanolamine at the site of autophagosome biogenesis.
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