Selective sorting and destruction of mitochondrial membrane proteins in aged yeast
Abstract
Mitochondrial dysfunction is a hallmark of aging, and underlies the development of many diseases. Cells maintain mitochondrial homeostasis through a number of pathways that remodel the mitochondrial proteome or alter mitochondrial content during times of stress or metabolic adaptation. Here, using yeast as a model system, we identify a new mitochondrial degradation system that remodels the mitochondrial proteome of aged cells. Unlike many common mitochondrial degradation pathways, this system selectively removes a subset of membrane proteins from the mitochondrial inner and outer membranes, while leaving the remainder of the organelle intact. Selective removal of preexisting proteins is achieved by sorting into a mitochondrial-derived compartment, or MDC, followed by release through mitochondrial fission and elimination by autophagy. Formation of MDCs requires the import receptors Tom70/71, and failure to form these structures exacerbates preexisting mitochondrial dysfunction, suggesting that the MDC pathway provides protection to mitochondria in times of stress.
Article and author information
Author details
Reviewing Editor
- Andrew Dillin, Howard Hughes Medical Institute, University of California, Berkeley, United States
Publication history
- Received: December 19, 2015
- Accepted: April 18, 2016
- Accepted Manuscript published: April 20, 2016 (version 1)
- Accepted Manuscript updated: April 25, 2016 (version 2)
- Version of Record published: June 1, 2016 (version 3)
Copyright
© 2016, Hughes 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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