A heat shock-responsive domain of human HSF1 that regulates transcription activation domain function.
Human heat shock factor 1 (HSF1) stimulates transcription from heat shock protein genes following stress. We have used chimeric proteins containing the GAL4 DNA binding domain to identify the transcriptional activation domains of HSF1 and a separate domain that is capable of regulating activation domain function. This regulatory domain conferred heat shock inducibility to chimeric proteins containing the activation domains. The regulatory domain is located between the transcriptional activation domains and the DNA binding domain of HSF1 and is conserved between mammalian and chicken HSF1 but is not found in HSF2 or HSF3. The regulatory domain was found to be functionally homologous between chicken and human HSF1. This domain does not affect DNA binding by the chimeric proteins and does not contain any of the sequences previously postulated to regulate DNA binding of HSF1. Thus, we suggest that activation of HSF1 by stress in humans is controlled by two regulatory mechanisms that separately confer heat shock-induced DNA binding and transcriptional stimulation.
Green
M
M
Department of Molecular Biology, Massachusetts General Hospital, Boston 02114, USA.
Schuetz
T J
TJ
Sullivan
E K
EK
Kingston
R E
RE
D000595:Amino Acid Sequence; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation; D006367:HeLa Cells; D000076249:Heat Shock Transcription Factors; D006358:Hot Temperature; D006801:Humans; D008969:Molecular Sequence Data; D010449:Peptide Mapping; D014157:Transcription Factors; D015533:Transcriptional Activation / Q000235:genetics*
D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D014157:Transcription Factors