Rcf2 revealed in cryo-EM structures of hypoxic isoforms of mature mitochondrial III-IV supercomplexes.

ABSTRACT: The organization of the mitochondrial electron transport chain proteins into supercomplexes (SCs) is now undisputed; however, their assembly process, or the role of differential expression isoforms, remain to be determined. In Saccharomyces cerevisiae, cytochrome c oxidase (CIV) forms SCs of varying stoichiometry with cytochrome bc₁ (CIII). Recent studies have revealed, in normoxic growth conditions, an interface made exclusively by Cox5A, the only yeast respiratory protein that exists as one of two isoforms depending on oxygen levels. Here we present the cryo-EM structures of the III₂-IV₁ and III₂-IV₂ SCs containing the hypoxic isoform Cox5B solved at 3.4 and 2.8 Å, respectively. We show that the change of isoform

SUBMITTER: Hartley AM 

PROVIDER: S-EPMC7196821 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature