The essential protein fap7 is involved in the oxidative stress response of Saccharomyces cerevisiae

Mol Microbiol. 2000 Feb;35(4):936-48. doi: 10.1046/j.1365-2958.2000.01768.x.


Pos9 (Skn7) is an important transcription factor that, together with Yap1, induces the expression of oxidative stress target genes in Saccharomyces cerevisiae. The activation of Pos9 upon an oxidative stress signal occurs post-translationally. In a mutant screen for factors involved in the activation of a Pos9-dependent reporter gene upon oxidative stress, we identified the mutant fap7-1 (for factor activating Pos9). This point mutant failed to activate a Gal4-Pos9 hybrid transcription factor, assayed by hydrogen peroxide-induced GAL1-lacZ reporter gene activities. Additionally, the fap7-1 mutant strain was sensitive to oxidative stress and revealed slow growth on glucose compared with the wild type. The fap7-1 mutation also affected the induction of the Pos9 target gene TPX1 and of a synthetic promoter previously identified to be regulated in a Yap1- and Pos9-dependent manner. This lack of induction was specific as the fap7-1 mutant response to other stresses such as sodium chloride or co-application of both hydrogen peroxide and sodium chloride was not affected, as tested with the Pos9-independent expression pattern of a TPS2-lacZ reporter system. We identified the gene YDL166c to be allelic to the FAP7 gene and to be essential. Fluorescence microscopy of Fap7-GFP fusion proteins indicated a nuclear localization of the Fap7 protein. Our data suggest that Fap7 is a nuclear factor important for Pos9-dependent target gene transcription upon oxidative stress.

MeSH terms

  • Adenylate Kinase
  • Amino Acid Sequence
  • Cell Nucleus / chemistry
  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / physiology
  • Fungal Proteins / genetics
  • Fungal Proteins / physiology*
  • Gene Expression Regulation, Fungal
  • Genes, Essential
  • Genetic Complementation Test
  • Green Fluorescent Proteins
  • Lac Operon / genetics
  • Luminescent Proteins / genetics
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Mutation
  • Nuclear Proteins / genetics
  • Nuclear Proteins / physiology*
  • Nucleoside-Triphosphatase
  • Osmotic Pressure
  • Oxidative Stress / genetics*
  • Phenotype
  • Phosphoric Monoester Hydrolases / genetics
  • Point Mutation
  • Recombinant Fusion Proteins / genetics
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins*
  • Sequence Alignment
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Transcription Factors / genetics
  • Transcription Factors / physiology


  • DNA, Fungal
  • DNA-Binding Proteins
  • Fungal Proteins
  • Luminescent Proteins
  • Nuclear Proteins
  • Recombinant Fusion Proteins
  • SKN7 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Transcription Factors
  • YAP1 protein, S cerevisiae
  • Green Fluorescent Proteins
  • Adenylate Kinase
  • FAP7 protein, S cerevisiae
  • trehalose-phosphatase
  • Phosphoric Monoester Hydrolases
  • Nucleoside-Triphosphatase