A short element required for turning off heat shock transcription factor: evidence that phosphorylation enhances deactivation.
Transcriptional activation of heat shock genes is mediated by a presynthesized nuclear protein, the heat shock factor (HSF), which transiently converts from an inactive to an active form in response to hyperthermia. It has been suggested that hyperphosphorylation of HSF upon heat shock triggers activation through the induction of a conformational change unmasking transcriptional activator domains. Here we report that a short conserved element is involved in returning yeast HSF to the inactive state after heat shock and show that deactivation can be enhanced by phosphorylation of adjacent serine residues. These results suggest that phosphorylation of HSF in yeast serves as a regulatory mechanism to deactivate HSF, rather than being involved in its activation.
Department of Molecular Biology, University of Aarhus, Denmark.
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Høj
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BK
Jakobsen
D000595:Amino Acid Sequence; D001483:Base Sequence; D017124:Conserved Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal / Q000235:genetics*; D006360:Heat-Shock Proteins; D007716:Kluyveromyces / Q000235:genetics* / Q000378:metabolism; D008957:Models, Genetic; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009842:Oligopeptides / Q000235:genetics; D010766:Phosphorylation; D011487:Protein Conformation; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D012694:Serine; D013696:Temperature; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation / Q000235:genetics
D004268:DNA-Binding Proteins; C067168:HSF1 protein, S cerevisiae; D006360:Heat-Shock Proteins; D009842:Oligopeptides; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D012694:Serine