An evidence based hypothesis on the existence of two pathways of mitochondrial crista formation

• Published in: eLife Vol. 5
• Main Authors: Harner, Max E, Unger, Ann-Katrin, Geerts, Willie Jc, Mari, Muriel, Izawa, Toshiaki, Stenger, Maria, Geimer, Stefan, Reggiori, Fulvio, Westermann, Benedikt, Neupert, Walter
• Format: Journal Article
• Language: English
• Published: England eLife Science Publications, Ltd 16.11.2016; eLife Sciences Publications Ltd; eLife Sciences Publications, Ltd
• Subjects: ATP synthase; Biochemistry; Biology; Biosynthesis; Cell Biology; crista formation; Cristae; Dimerization; DNA sequencing; F1FO-ATP synthase; Gene Expression; GTP Phosphohydrolases - genetics; GTP Phosphohydrolases - metabolism; GTP-Binding Proteins - genetics; GTP-Binding Proteins - metabolism; Homeostasis; Hypotheses; Invaginations; Membranes; Metabolism; Metabolites; Methods; Mgm1/Opa1; MICOS; Microscopy; Mitochondria; Mitochondria - genetics; Mitochondria - metabolism; Mitochondria - ultrastructure; Mitochondrial DNA; Mitochondrial Dynamics - physiology; mitochondrial fusion; Mitochondrial Membranes - metabolism; Mitochondrial Membranes - ultrastructure; Mitochondrial Proteins - genetics; Mitochondrial Proteins - metabolism; Mitochondrial Proton-Translocating ATPases - genetics; Mitochondrial Proton-Translocating ATPases - metabolism; Nucleotide sequencing; Organelle Biogenesis; Oxidative phosphorylation; Phosphorylation; Physiological aspects; Protein Multimerization; Proteins; Respiration; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae - ultrastructure; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - metabolism; Structure-function relationships; Yeast; cell biology; MICOS; crista formation; mitochondria; biochemistry; F1FO-ATP synthase; Mgm1/Opa1; mitochondrial fusion; S. cerevisiae
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/elife.18853

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 the 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 F F -ATP synthase and the 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.