title: Sch9 regulates intracellular protein ubiquitination by controlling stress responses.
abstract: Protein ubiquitination and the subsequent degradation are important means by which aberrant proteins are removed from cells, a key requirement for long-term survival. In this study, we found that the overall level of ubiquitinated proteins dramatically decreased as yeast cell grew from log to stationary phase. Deletion of SCH9, a gene encoding a key protein kinase for longevity control, decreased the level of ubiquitinated proteins in log phase and this effect could be reversed by restoring Sch9 function. We demonstrate here that the decrease of ubiquitinated proteins in sch9Δ cells in log phase is not caused by changes in ubiquitin expression, proteasome activity, or autophagy, but by enhanced expression of stress response factors and a decreased level of oxidative stress. Our results revealed for the first time how Sch9 regulates the level of ubiquitinated proteins and provides new insight into how Sch9 controls longevity.
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
authors.forename: Beibei
authors.initials: B
authors.lastname: Qie
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Lyu
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Lyu
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
authors.forename: Xuejie
authors.initials: X
authors.lastname: Gao
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: School of Medicine, Faculty of Health, Deakin University, Waurn Ponds, Victoria, Australia.
authors.forename: Wei
authors.initials: W
authors.lastname: Duan
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China. Electronic address: zhangnianhui@scu.edu.cn.
authors.forename: Nianhui
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China. Electronic address: dulinfang@scu.edu.cn.
authors.forename: Linfang
authors.initials: L
authors.lastname: Du
authors.affiliation: Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu, Sichuan 610064, China. Electronic address: kliu@scu.edu.cn.
authors.forename: Ke
authors.initials: K
authors.lastname: Liu
mesh_terms: D001343:Autophagy; D000071190:Autophagy-Related Protein 8 Family; D006861:Hydrogen Peroxide / Q000633:toxicity; D007976:Leupeptins / Q000494:pharmacology; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000737:chemistry / Q000378:metabolism; D061988:Proteasome Inhibitors / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism; D057149:Ubiquitinated Proteins / Q000378:metabolism; D054875:Ubiquitination / Q000187:drug effects
chemical_list: C113757:ATG8 protein, S cerevisiae; D000071190:Autophagy-Related Protein 8 Family; D007976:Leupeptins; D008869:Microtubule-Associated Proteins; D061988:Proteasome Inhibitors; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D029701:Saccharomyces cerevisiae Proteins; D025801:Ubiquitin; D057149:Ubiquitinated Proteins; D006861:Hydrogen Peroxide; D017346:Protein Serine-Threonine Kinases; C530964:SCH9 protein, S cerevisiae; D046988:Proteasome Endopeptidase Complex; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde
keywords: Hydrogen peroxide; Oxidation; SCH9; Ubiquitination; Yeast