Overexpression of two transcriptional factors, Kin28 and Pog1, suppresses the stress sensitivity caused by the rsp5 mutation in Saccharomyces cerevisiae.
Rsp5 is an essential and multi-functional E3 ubiquitin ligase in Saccharomyces cerevisiae. The Ala401Glu rsp5 mutant, which is hypersensitive to various stresses, was isolated previously. To understand the function of Rsp5 in stress responses, suppressor genes whose overexpression allows rsp5(A401E) cells to grow at a high temperature were screened. The KIN28 and POG1 genes, encoding a subunit of the transcription factor TFIIH and a putative transcriptional activator, respectively, were identified as multicopy suppressors of not only high temperature but also LiCl stresses. The overexpression of Kin28 and Pog1 in rsp5(A401E) cells led to an increase in the transcriptional level of some stress proteins when exposed to a temperature up-shift. Based on DNA microarray analysis under LiCl stress, it appears that the transcriptional level of some proteasome components is slightly increased in rsp5(A401E) cells overexpressing Kin28 or Pog1. These results suggest that the overexpression of Kin28 and Pog1 enhances the protein refolding and degradation pathways in rsp5(A401E) cells.
Demae
Mika
M
Graduate School of Biological Sciences, Nara Institute of Science and Technology,Ikoma, Nara, Japan.
Murata
Yoshinori
Y
Hisano
Mirei
M
Haitani
Yutaka
Y
Shima
Jun
J
Takagi
Hiroshi
H
D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism*; D056827:Endosomal Sorting Complexes Required for Transport; D015966:Gene Expression Regulation, Fungal; D018869:Heat-Shock Response / Q000235:genetics; D018021:Lithium Chloride / Q000494:pharmacology; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism*; D051758:Transcription Factor TFIIH / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D043743:Ubiquitin-Protein Ligase Complexes / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation
D056827:Endosomal Sorting Complexes Required for Transport; D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; D051758:Transcription Factor TFIIH; D043743:Ubiquitin-Protein Ligase Complexes; D018844:Cyclin-Dependent Kinases; C084210:Kin28 protein kinase, S cerevisiae; C469287:RSP5 protein, S cerevisiae; D018021:Lithium Chloride