Degradation of cytochrome oxidase subunits in mutants of yeast lacking cytochrome c and suppression of the degradation by mutation of yme1.
We have confirmed by spectral analysis that cytochrome oxidase is not present in strains of the yeast Saccharomyces cerevisiae having a primary deficiency in cytochrome c, and we have demonstrated by immunological procedures that such strains lack the mitochondrially encoded subunits I, II, and III of cytochrome oxidase. Furthermore, pulse-chase experiments demonstrated that subunit II is rapidly degraded in vivo. This degradation can be at least partially suppressed by disruption of the nuclear gene YME1, which encodes a putative ATP-Zn(2+)-dependent protease. We suggest that the cytochrome oxidase subunits are not properly assembled in the absence of cytochrome c, and that Yme1 and possibly other proteases degrade the unassembled mitochondrial-encoded subunits of cytochrome oxidase.
Pearce
D A
DA
Department of Biochemistry, University of Rochester School of Medicine and Dentistry, New York 14642, USA.
Sherman
F
F
D049069:ATP-Dependent Proteases; D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism; D003574:Cytochrome c Group / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D008928:Mitochondria / Q000201:enzymology; D009154:Mutation; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins
D003574:Cytochrome c Group; D029701:Saccharomyces cerevisiae Proteins; D003576:Electron Transport Complex IV; D049069:ATP-Dependent Proteases; C082702:YME1 protein, S cerevisiae; D000251:Adenosine Triphosphatases