Septins modulate the autophagy response after nutrient starvation
Luis Perucho-Jaimes1, Jonathan Do1, Alexandria Van Elgort1
1Department of Molecular and Cellular Biology, University of California, Davis, Davis, CA 95616.
Molecular Biology of the Cell
|November 1, 2023
Summary
Septin filaments reorganize during nutrient deprivation to modulate autophagy. These structures limit Atg9 membrane access, altering autophagy kinetics and duration for cellular adaptation.
Area of Science:
- Cell Biology
- Molecular Biology
Background:
- Macroautophagy (autophagy) is crucial for survival during nutrient scarcity.
- Mechanisms regulating autophagy dynamics remain incompletely understood.
Purpose of the Study:
- To investigate the role of septins in modulating the autophagy response in budding yeast.
- To elucidate how septin structures influence Atg9 membrane dynamics and autophagosome biogenesis.
Main Methods:
- Microscopy of budding yeast undergoing nutrient deprivation.
- Analysis of septin filament assembly and localization.
- Tracking of Atg9 membrane dynamics in wild-type and mutant yeast.
Main Results:
- Septin filaments assemble into cortical patches upon autophagy induction.
- These septin structures mature and associate with Atg9 membranes at the endoplasmic reticulum.
- Loss of septin structures disrupts Atg9 membrane diffusion and alters autophagy kinetics and duration.
Conclusions:
- Septins reorganize at the cell cortex to regulate Atg9 membrane access to autophagosome assembly sites.
- Septins act as a key modulator of the autophagy response during nutrient deprivation.
- This regulation impacts the efficiency and duration of the cellular starvation response.
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