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Release of cytochrome c and decrease of cytochrome c oxidase in Bax-expressing yeast cells, and prevention of these effects by coexpression of Bcl-xL.

S Manon·B Chaudhuri·M Guérin
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Abstract

The characteristics of mitochondria of yeast cells expressing the pro-apoptotic gene Bax or coexpressing Bax and the anti-apoptotic gene Bcl-xL have been investigated in whole cells, isolated mitochondria and permeabilized spheroplasts. It is found that Bax-induced growth arrest of yeast cells is related to two defects in the respiratory chain: (i) a decrease in the amount of cytochrome c oxidase, the terminal enzyme of the respiratory chain, and (ii) a dramatic increase in the release of cytochrome c to the cytosol. Other components of the inner mitochondrial membrane (bc1 complex and F0F1-ATPase) are unaffected. Coexpression of Bcl-xL almost fully prevented the effect of Bax. Surprisingly, these results obtained in yeast parallel similar observations reported in mammalian cells.

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ApoptosisCytochrome a GroupCytochrome c GroupElectron Transport Complex IVEnergy MetabolismGalactoseGene ExpressionKineticsMembrane ProteinsMitochondriaProto-Oncogene ProteinsProto-Oncogene Proteins c-bcl-2Proton-Translocating ATPasesRecombinant ProteinsSaccharomyces cerevisiaeSpectrophotometrySpheroplastsbcl-2-Associated X Proteinbcl-X ProteinJournal ArticleResearch Support, Non-U.S. Gov't

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S Manon, B Chaudhuri, M Guérin. 1997-09-22. Release of cytochrome c and decrease of cytochrome c oxidase in Bax-expressing yeast cells, and prevention of these effects by coexpression of Bcl-xL.. https://doi.org/10.1016/s0014-5793(97)01087-9

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