Deletion of conserved protein phosphatases reverses defects associated with mitochondrial DNA damage in Saccharomyces cerevisiae.
Mitochondrial biogenesis is regulated by signaling pathways sensitive to extracellular conditions and to the internal environment of the cell. Therefore, treatments for disease caused by mutation of mtDNA may emerge from studies of how signal transduction pathways command mitochondrial function. We have examined the role of phosphatases under the control of the conserved α4/Tap42 protein in cells lacking a mitochondrial genome. We found that deletion of protein phosphatase 2A (PP2A) or of protein phosphatase 6 (PP6) protects cells from the reduced proliferation, mitochondrial protein import defects, lower mitochondrial electrochemical potential, and nuclear transcriptional response associated with mtDNA damage. Moreover, PP2A or PP6 deletion allows viability of a sensitized yeast strain after mtDNA loss. Interestingly, the Saccharomyces cerevisiae ortholog of the mammalian AMP-activated protein kinase was required for the full benefits of PP6 deletion and also for proliferation of otherwise wild-type cells lacking mtDNA. Our work highlights the important role that nutrient-responsive signaling pathways can play in determining the response to mitochondrial dysfunction.
['Garipler|Görkem|G|', 'Mutlu|Nebibe|N|', 'Lack|Nathan A|NA|', 'Dunn|Cory D|CD|']
D004249:DNA Damage D004272:DNA, Mitochondrial D005434:Flow Cytometry D009154:Mutation D010749:Phosphoprotein Phosphatases D012441:Saccharomyces cerevisiae D017384:Sequence Deletion D059467:Transcriptome
TOR bioenergetics mitochondria nutrient signaling petite-negative