A reversible non-membrane bound stress assembly that confers cell viability by preserving ERES components during amino-acid starvation
Abstract
Nutritional restriction leads to protein translation attenuation that results in the storage and degradation of free mRNAs in cytoplasmic assemblies. Here, we show in Drosophila S2 cells that amino-acid starvation also leads to the inhibition of another major anabolic pathway, the protein transport through the secretory pathway, and to the formation of a novel reversible non-membrane bound stress assembly, the Sec body that incorporates components of the ER exit sites. Sec body formation does not depend on membrane traffic in the early secretory pathway, yet requires both Sec23 and Sec24AB. Sec bodies have liquid droplet-like properties and they act as a protective reservoir for ERES components to rebuild a functional secretory pathway after re-addition of amino-acids acting as a part of a survival mechanism. Taken together, we propose that the formation of these structures is a novel stress response mechanism to provide cell viability during and after nutrient stress.
Article and author information
Author details
Reviewing Editor
- Jodi Nunnari, University of California, Davis, United States
Version history
- Received: July 23, 2014
- Accepted: November 10, 2014
- Accepted Manuscript published: November 11, 2014 (version 1)
- Version of Record published: December 4, 2014 (version 2)
- Version of Record updated: November 11, 2016 (version 3)
Copyright
© 2014, Zacharogianni et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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