title: Mitochondrial respiratory thresholds regulate yeast chronological life span and its extension by caloric restriction.
abstract: We have explored the role of mitochondrial function in aging by genetically and pharmacologically modifying yeast cellular respiration production during the exponential and/or stationary growth phases and determining how this affects chronological life span (CLS). Our results demonstrate that respiration is essential during both growth phases for standard CLS, but that yeast have a large respiratory capacity, and only deficiencies below a threshold (~40% of wild-type) significantly curtail CLS. Extension of CLS by caloric restriction also required respiration above a similar threshold during exponential growth and completely alleviated the need for respiration in the stationary phase. Finally, we show that supplementation of media with 1% trehalose, a storage carbohydrate, restores wild-type CLS to respiratory-null cells. We conclude that mitochondrial respiratory thresholds regulate yeast CLS and its extension by caloric restriction by increasing stress resistance, an important component of which is the optimal accumulation and mobilization of nutrient stores.
authors: Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA.
authors: Alejandro
authors: A
authors: Ocampo
authors: Jingjing
authors: J
authors: Liu
authors: Elizabeth A
authors: EA
authors: Schroeder
authors: Gerald S
authors: GS
authors: Shadel
authors: Antoni
authors: A
authors: Barrientos
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000935:Antifungal Agents / Q000494:pharmacology; D000968:Antimycin A / Q000494:pharmacology; D003470:Culture Media / Q000737:chemistry*; D055786:Gene Knockout Techniques; D050296:Microbial Viability; D008928:Mitochondria / Q000378:metabolism* / Q000502:physiology; D009840:Oligomycins / Q000494:pharmacology; D018384:Oxidative Stress; D010101:Oxygen Consumption; D019869:Phosphatidylinositol 3-Kinases / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D019342:Acetic Acid; D000935:Antifungal Agents; D000968:Antimycin A; D003470:Culture Media; D009840:Oligomycins; D019869:Phosphatidylinositol 3-Kinases; D017382:Reactive Oxygen Species; D029701:Saccharomyces cerevisiae Proteins; C083324:TOR1 protein, S cerevisiae