Mitochondrial dysfunction reduces yeast replicative lifespan by elevating RAS-dependent ROS production by the ER-localized NADPH oxidase Yno1.
Dae-Gwan YiSujin HongWon-Ki HuhPublished in: PloS one (2018)
Mitochondrial dysfunction leads to the accumulation of reactive oxygen species (ROS) which is associated with cellular dysfunction, disease etiology, and senescence. Here, we used the eukaryotic model Saccharomyces cerevisiae, commonly studied for cellular aging, to demonstrate how defective mitochondrial function affects yeast replicative lifespan (RLS). We show that RLS of respiratory-deficient cells decreases significantly, indicating that the maintenance of RLS requires active respiration. The shortening of RLS due to mitochondrial dysfunction was not related to the accumulation of extrachromosomal ribosomal DNA circles, a well-known cause of aging in yeast. Instead, intracellular ROS and oxidatively damaged proteins increased in respiratory-deficient mutants. We show that, while the protein kinase A activity is not elevated, ROS generation in respiratory-deficient cells depends on RAS signaling pathway. The ER-localized NADPH oxidase Yno1 also played a role in producing ROS. Our data suggest that a severe defect in mitochondrial respiration accelerates cellular aging by disturbing protein homeostasis in yeast.
Keyphrases
- reactive oxygen species
- saccharomyces cerevisiae
- induced apoptosis
- dna damage
- cell death
- cell cycle arrest
- wild type
- signaling pathway
- oxidative stress
- pi k akt
- endoplasmic reticulum stress
- endothelial cells
- big data
- single molecule
- small molecule
- artificial intelligence
- cell free
- electronic health record
- deep learning
- amino acid
- data analysis
- nucleic acid