title: A novel domain of the yeast heat shock factor that regulates its activation function.
abstract: Heat shock factor Hsf1 of the yeast Saccharomyces cerevisiae binds to the heat shock element (HSE) of a subset of genes and activates their transcription in response to various environmental stresses. Hsf1 protein contains discrete domains respectively involved in DNA-binding, trimerization, transcription activation, and transcription repression. Here we have identified a novel domain rich in basic amino acids at the extreme C-terminus of Hsf1. Deletion or point mutations of the C-terminal basic region caused an inefficient heat shock response of genes containing noncanonical HSEs such as CUP1 and HSP26. The basic region is also essential for oxidative stress-inducible transcription of CUP1 by Hsf1. By contrast, it was dispensable for heat induction through the canonical HSE. We suggest that the basic region is a modulator involved in regulation of the Hsf1-mediated activation depending on the architecture of its binding site.
authors.affiliation: School of Health Sciences, Faculty of Medicine, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa 920-0942, Japan. sakurai@kenroku.kanazawa-u.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Sakurai
authors.forename: T
authors.initials: T
authors.lastname: Fukasawa
mesh_terms: D020816:Amino Acid Motifs / Q000502:physiology; D002352:Carrier Proteins; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004742:Enhancer Elements, Genetic / Q000502:physiology; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D018869:Heat-Shock Response / Q000502:physiology; D008668:Metallothionein / Q000235:genetics; D016297:Mutagenesis, Site-Directed; D018384:Oxidative Stress / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000502:physiology
chemical_list: C500769:CUP1-1 protein, S cerevisiae; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C067168:HSF1 protein, S cerevisiae; C499528:HSP26 protein, S cerevisiae; D006360:Heat-Shock Proteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C007121:copper thionein; D008668:Metallothionein