title: Rsp5 regulates expression of stress proteins via post-translational modification of Hsf1 and Msn4 in Saccharomyces cerevisiae.
abstract: Rsp5 is an essential E3 ubiquitin ligase in Saccharomyces cerevisiae and is known to ubiquitinate plasma membrane permeases followed by endocytosis and vacuolar degradation. We previously isolated the rsp5 mutant that is hypersensitive to various stresses, suggesting that Rsp5 is involved in degradation of stress-induced abnormal proteins. Here, we analyzed the ability to refold the proteins by stress proteins in the rsp5 mutant. The transcription of stress protein genes in the rsp5 mutant was significantly lower than that in the wild-type strain when exposed to temperature up-shift, ethanol or sorbitol. Interestingly, the amounts of transcription factors Hsf1 and Msn4 were remarkably defective in the rsp5 mutant. These results suggest that expression of stress proteins are mediated by Rsp5 and that Rsp5 primarily regulates post-translational modification of Hsf1 and Msn4.
authors.affiliation: Department of Bioscience, Fukui Prefectural University, Eiheiji-cho, Fukui, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Haitani
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shimoi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takagi
mesh_terms: D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism*; D056827:Endosomal Sorting Complexes Required for Transport; D006360:Heat-Shock Proteins / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism*; D043743:Ubiquitin-Protein Ligase Complexes / Q000235:genetics / Q000502:physiology*
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; D056827:Endosomal Sorting Complexes Required for Transport; C067168:HSF1 protein, S cerevisiae; D006360:Heat-Shock Proteins; C081937:MSN4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D043743:Ubiquitin-Protein Ligase Complexes; C469287:RSP5 protein, S cerevisiae