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Updated: Jul 16, 2026
07:20
Imaging ATG9A, a Multi-Spanning Membrane Protein
Published on: June 16, 2023
Atg9 trafficking in autophagy-related pathways
Congcong He1, Daniel J Klionsky
1Life Sciences Institute, Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109-2216, USA.
Autophagy
|March 3, 2007
Summary
Autophagy membrane origin remains unknown. A new model shows Atg11 protein transports Atg9 protein to the phagophore assembly site (PAS), potentially acting as a membrane shuttle for vesicle formation in yeast selective autophagy.
Area of Science:
- Cell Biology
- Molecular Biology
- Autophagy Research
Background:
- The origin of the autophagosomal membrane and lipid delivery mechanisms in autophagy are not fully understood.
- Atg9, an integral membrane protein essential for autophagosome formation, is implicated as a membrane carrier in autophagy.
- In yeast (S. cerevisiae), Atg9 exhibits dynamic cycling between peripheral locations and the pre-autophagosomal structure/phagophore assembly site (PAS).
Purpose of the Study:
- To elucidate the role of Atg9 in autophagosome formation and membrane delivery.
- To propose and investigate a model for Atg9 cycling and its function in selective autophagy.
- To understand the molecular mechanisms underlying membrane trafficking during yeast autophagy.
Main Methods:
- Yeast two-hybrid screening to identify Atg9 binding partners.
- Analysis of Atg9 cycling dynamics and its relationship with the actin cytoskeleton.
- Investigating the role of Atg11 in Atg9 transport to the PAS.
Main Results:
- Atg11 was identified as a binding partner of Atg9.
- A model was proposed where Atg11 mediates the anterograde transport of Atg9 to the PAS along the actin cytoskeleton.
- This Atg9 delivery process is suggested to function as a membrane shuttle for vesicle assembly during yeast selective autophagy.
Conclusions:
- The study proposes a novel model for Atg9 cycling mediated by Atg11.
- This mechanism highlights the potential role of Atg11-Atg9 interaction in delivering membrane components for autophagosome biogenesis.
- The findings provide insights into membrane trafficking during yeast selective autophagy, including pexophagy.
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