The coordinated action of the MVB pathway and autophagy ensures cell survival during starvation
- Medical University of Innsbruck, Austria
- University of Vienna, Austria
- University of Natural Resources and Applied Biosciences, Austria
Abstract
The degradation and recycling of cellular components is essential for cell growth and survival. Here we show how selective and non-selective lysosomal protein degradation pathways cooperate to ensure cell survival upon nutrient limitation. A quantitative analysis of starvation-induced proteome remodeling in yeast reveals comprehensive changes already in the first three hours. In this period, many different integral plasma membrane proteins undergo endocytosis and degradation in vacuoles via the multivesicular body (MVB) pathway. Their degradation becomes essential to maintain critical amino acids levels that uphold protein synthesis early during starvation. This promotes cellular adaptation, including the de novo synthesis of vacuolar hydrolases to boost the vacuolar catabolic activity. This order of events primes vacuoles for the efficient degradation of bulk cytoplasm via autophagy. Hence, a catabolic cascade including the coordinated action of the MVB pathway and autophagy is essential to enter quiescence to survive extended periods of nutrient limitation.
Article and author information
Author details
Reviewing Editor
- Noboru Mizushima, The University of Tokyo, Japan
Version history
- Received: March 26, 2015
- Accepted: April 19, 2015
- Accepted Manuscript published: April 22, 2015 (version 1)
- Version of Record published: May 8, 2015 (version 2)
Copyright
© 2015, Müller 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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The coordinated action of the MVB pathway and autophagy ensures cell survival during starvation
eLife 4:e07736.
https://doi.org/10.7554/eLife.07736
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