Molecular cloning and expression of a human heat shock factor, HSF1.
Human cells respond to heat stress by inducing the binding of a preexisting transcriptional activator (heat shock factor, HSF) to DNA. We have isolated recombinant DNA clones for a human HSF (HSF1) by screening cDNA libraries with a human cDNA fragment. The human HSF1 probe was produced by the PCR with primers deduced from conserved amino acids in the Drosophila and yeast HSF sequences. The human HSF1 mRNA is constitutively expressed in HeLa cells under nonshock conditions and encodes a protein with four conserved leucine zipper motifs. Like its counterpart in Drosophila, human HSF1 produced in Escherichia coli in the absence of heat shock is active as a DNA binding transcription factor, suggesting that the intrinsic activity of HSF is under negative control in human cells. Surprisingly, an independently isolated human HSF clone, HSF2, is related to but significantly different from HSF1 [Schuetz, T. J., Gallo, G. J., Sheldon, L., Tempst, P. & Kingston, R. E. (1991) Proc. Natl. Acad. Sci. USA 88, 6911-6915].
Rabindran
S K
SK
Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892.
Giorgi
G
G
Clos
J
J
Wu
C
C
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D004330:Drosophila / Q000235:genetics; D015723:Gene Library; D006367:HeLa Cells / Q000502:physiology; D000076249:Heat Shock Transcription Factors; D006801:Humans; D016350:Leucine Zippers / Q000235:genetics; D016393:Lymphoma, B-Cell; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D016366:Open Reading Frames; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000302:isolation & purification; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011994:Recombinant Proteins; D014157:Transcription Factors