Selective sorting and destruction of mitochondrial membrane proteins in aged yeast
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
- Andrew Dillin, Howard Hughes Medical Institute, University of California, Berkeley, United States
- 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)
© 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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