An evidence based hypothesis on the existence of two pathways of mitochondrial crista formation
- Max Planck Institute of Biochemistry, Germany
- Universität Bayreuth, Germany
- Universiteit Utrecht, Netherlands
- University of Groningen, Netherlands
Abstract
Metabolic function and architecture of mitochondria are intimately linked. More than 60 years ago, cristae were discovered as characteristic elements of mitochondria that harbor the protein complexes of oxidative phosphorylation, but how cristae are formed, remained an open question. Here we present experimental results obtained with yeast that support a novel hypothesis on the existence of two molecular pathways that lead to generation of lamellar and tubular cristae. Formation of lamellar cristae depends on the mitochondrial fusion machinery through a pathway that is required also for homeostasis of mitochondria and mitochondrial DNA. Tubular cristae are formed via invaginations of the inner boundary membrane by a pathway independent of the fusion machinery. Dimerization of the F1FO-ATP synthase and presence of the MICOS complex are necessary for both pathways. The proposed hypothesis is suggested to apply also to higher eukaryotes, since the key components are conserved in structure and function throughout evolution.
Article and author information
Author details
Benedikt Westermann
Funding
Max-Planck-Gesellschaft
- Max E Harner
- Ann-Katrin Unger
- Toshiaki Izawa
- Walter Neupert
Carl Friedrich von Siemens Stiftung
- Walter Neupert
Jung-Stiftung für Wissenschaft und Forschung
- Max E Harner
Ludwig-Maximilians-Universität München
- Max E Harner
Netherlands organization for Scientific Research (DN82-303)
- Fulvio Reggiori
Deutsche Forschungsgemeinschaft (DN82-303)
- Fulvio Reggiori
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (CRSII3_154421)
- Fulvio Reggiori
ZonMw (ZonMW VICI)
- Fulvio Reggiori
Netherlands organization for Scientific Research (822.02.014)
- Fulvio Reggiori
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2016, Harner 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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An evidence based hypothesis on the existence of two pathways of mitochondrial crista formation
eLife 5:e18853.
https://doi.org/10.7554/eLife.18853
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