title: Transcriptional response to mitochondrial NADH kinase deficiency in Saccharomyces cerevisiae.
abstract: Yeast cells lacking the mitochondrial NADH kinase encoded by POS5 display increased sensitivity to hydrogen peroxide, a slow-growth phenotype, reduced mitochondrial function and increased levels of mitochondrial protein oxidation and mtDNA mutations. Here we examined gene expression in pos5Delta cells, comparing these data to those from cells containing deletions of superoxide dismutase-encoding genes SOD1 or SOD2. Surprisingly, stress-response genes were down-regulated in pos5Delta, sod1Delta and sod2Delta cells, implying that cells infer stress levels from mitochondrial activity rather than sensing reactive oxygen species directly. Additionally, pos5Delta, but not sod1 or sod2, cells displayed an anaerobic expression profile, indicating a defect in oxygen sensing that is specific to pos5, and is not a general stress-response. Finally, the pos5Delta expression profile is quite similar to the hap1Delta expression profile previously reported, which may indicate a shared mechanism.
authors.affiliation: Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709, USA.
authors.forename: Gregory R
authors.initials: GR
authors.lastname: Stuart
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Humble
authors.forename: Micheline K
authors.initials: MK
authors.lastname: Strand
authors.forename: William C
authors.initials: WC
authors.lastname: Copeland
mesh_terms: D000935:Antifungal Agents / Q000633:toxicity; D015536:Down-Regulation; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D006861:Hydrogen Peroxide / Q000633:toxicity; D024101:Mitochondrial Proteins / Q000172:deficiency*; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000172:deficiency*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D013482:Superoxide Dismutase / Q000235:genetics; D000072105:Superoxide Dismutase-1; D015854:Up-Regulation; D000099156:Superoxide Dismutase 2
chemical_list: D000935:Antifungal Agents; D006861:Hydrogen Peroxide; D024101:Mitochondrial Proteins; D017853:Phosphotransferases (Alcohol Group Acceptor); D029701:Saccharomyces cerevisiae Proteins; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; D000099156:Superoxide Dismutase 2; C060670:POS5 protein, S cerevisiae