Active Ras2 in mitochondria promotes regulated cell death in a cAMP/PKA pathway‐dependent manner in budding yeast

Abstract

Previously, we showed that an aberrant accumulation of activated Ras in mitochondria correlates with an increase in apoptosis. In this article, we show that lack of trehalose-6P-synthase, known to trigger apoptosis in Saccharomyces cerevisiae, induces localization of active Ras proteins in mitochondria, confirming the above-mentioned correlation. Next, by characterizing the ras1D and ras2D mutants, we show that active Ras2 proteins, which accumulate in the mitochondria following addition of acetic acid (a pro-apoptotic stimulus), are likely the GTPases involved in regulated cell death, while active Ras1 proteins, constitutively localized in mitochondria, might be involved in a pro-survival molecular machinery. Finally, by characterizing the gpa2D and cyr1D mutants, in which the cAMP/PKA pathway is compromised, we show that active mitochondrial Ras proteins promote apoptosis through the cAMP/PKA pathway.

To each its own: Mechanisms of cross-talk between GPI biosynthesis and cAMP-PKA signaling in Candida albicans versus Saccharomyces cerevisiae

“…5 A ). It may also be found in the nucleus in wild type cells grown in glucose or localize to the mitochondria under specific conditions ( 133 , 134 ).

Figure 5 Ras proteins of Saccharomyces cerevisiae and Candida albicans .

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