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Updated: May 20, 2026
07:20
Imaging ATG9A, a Multi-Spanning Membrane Protein
Published on: June 16, 2023
Autophagy regulation through Atg9 traffic.
Fulvio Reggiori1, Sharon A Tooze
1Department of Cell Biology, University Medical Center Utrecht, 3584CX Utrecht, Netherlands.
The Journal of Cell Biology
|July 25, 2012
Summary
Autophagosome formation relies on membrane expansion. New research reveals Atg9 vesicles initiate this process during starvation, assembling into autophagosomes and recycling Atg9 to prevent degradation.
Area of Science:
- Cell Biology
- Molecular Biology
- Autophagy Research
Background:
- Autophagosome formation is crucial for cellular homeostasis, particularly during nutrient starvation.
- Rapid membrane expansion is a known prerequisite for autophagosome biogenesis.
Purpose of the Study:
- To elucidate the mechanism of vesicle-mediated initiation of autophagosome biogenesis.
- To characterize the role and dynamics of Atg9 vesicles in autophagy.
Main Methods:
- Observation of Atg9 vesicle formation and behavior during nutrient starvation.
- Characterization of Atg9 vesicle size and Atg9 content.
Main Results:
- Atg9 vesicles are generated de novo during starvation, measuring approximately 30-60 nm in diameter.
- Each Atg9 vesicle contains around 30 molecules of Atg9.
- These vesicles assemble to form the autophagosome structure.
- Atg9 within the autophagosome membrane is recycled to prevent its degradation.
Conclusions:
- Atg9 vesicles play a pivotal role in initiating autophagosome formation through a vesicle-mediated mechanism.
- The dynamic recycling of Atg9 is essential for efficient autophagosome biogenesis and cellular survival under starvation conditions.
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