Mfn2 ubiquitination by PINK1/parkin gates the p97-dependent release of ER from mitochondria to drive mitophagy
- Montreal Neurological Institute and Hospital, McGill University, Canada
- McGill University, Canada
- University of Lübeck, Germany
Abstract
Despite their importance as signaling hubs, the function of mitochondria-ER contact sites in mitochondrial quality control pathways remains unexplored. Here we describe a mechanism by which Mfn2, a mitochondria-ER tether, gates the autophagic turnover of mitochondria by PINK1 and parkin. Mitochondria-ER appositions are destroyed during mitophagy, and reducing mitochondria-ER contacts increases the rate of mitochondrial degradation. Mechanistically, parkin/PINK1 catalyze a rapid burst of Mfn2 phosphoubiquitination to trigger p97-dependent disassembly of Mfn2 complexes from the outer mitochondrial membrane, dissociating mitochondria from the ER. We additionally demonstrate that a major portion of the facilitatory effect of p97 on mitophagy is epistatic to Mfn2 and promotes the availability of other parkin substrates such as VDAC1. Finally, we reconstitute the action of these factors on Mfn2 and VDAC1 ubiquitination in a cell-free assay. We show that mitochondria-ER tethering suppresses mitophagy and describe a parkin-/PINK1-dependent mechanism that regulates the destruction of mitochondria-ER contact sites.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all Figures.
Article and author information
Author details
Funding
Canadian Institutes of Health Research (Canada Graduate Scholarship)
- Gian-Luca McLelland
Canadian Institutes of Health Research (Foundation Grant)
- Edward A Fon
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, McLelland 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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Mfn2 ubiquitination by PINK1/parkin gates the p97-dependent release of ER from mitochondria to drive mitophagy
eLife 7:e32866.
https://doi.org/10.7554/eLife.32866
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