Coi1 is a novel assembly factor of the yeast complex III–complex IV supercomplex

  • The yeast bc1 complex (complex III) and cytochrome oxidase (complex IV) are mosaics of core subunits encoded by the mitochondrial genome and additional nuclear-encoded proteins imported from the cytosol. Both complexes build in the mitochondrial inner membrane various supramolecular assemblies. The formation of the individual complexes and their supercomplexes depends on the activity of dedicated assembly factors. We identified a so far uncharacterized mitochondrial protein (open reading frame YDR381C-A) as an important assembly factor for complex III, complex IV, and their supercomplexes. Therefore, we named this protein Cox interacting (Coi) 1. Deletion of COI1 results in decreased respiratory growth, reduced membrane potential, and hampered respiration, as well as slow fermentative growth at low temperature. In addition, coi1Δ cells harbour reduced steady-state levels of subunits of complexes III and IV as well as of the assembled complexes and supercomplexes. Interaction of Coi1 with respiratory chain subunits seems transient, as it appears to be a stoichiometric subunit neither of complex III nor of complex IV. Collectively, this work identifies a novel protein that plays a role in the assembly of the mitochondrial respiratory chain.
Author:Ravi K. Singhal, Christine Kruse, Juliana HeidlerORCiD, Valentina Strecker, Klaus Zwicker, Lea Düsterwald, Benedikt Westermann, Johannes Herrmann, Ilka WittigORCiD, Doron Rapaport
Pubmed Id:
Parent Title (English):Molecular biology of the cell
Publisher:American Society for Cell Biology
Place of publication:Bethesda, Md.
Contributor(s):Anne Spang
Document Type:Article
Year of Completion:2017
Date of first Publication:2017/08/09
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2018/01/02
Page Number:14
First Page:2609
Last Page:2622
October 1, 2017 © 2017 Singhal et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (
Institutes:Medizin / Medizin
Exzellenzcluster / Exzellenzcluster Makromolekulare Komplexe
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Licence (German):License LogoCreative Commons - Namensnennung-Keine kommerzielle Nutzung-Weitergabe unter gleichen Bedingungen