Heat shock factor 1 represses transcription of the IL-1beta gene through physical interaction with the nuclear factor of interleukin 6.
Heat shock factor (HSF) 1 is the major heat shock transcription factor that regulates stress-inducible synthesis of heat shock proteins and is also essential in protection against endotoxic shock. Following our previous study, which demonstrated the transcriptional repression of the IL-1beta gene by HSF1 (Cahill, C. M., Waterman, W. R., Xie, Y., Auron, P. E., and Calderwood, S. K. (1996) J. Biol. Chem. 271, 24874-24879), we have examined the mechanisms of transcriptional repression. Our studies show that HSF1 represses the lipopolyliposaccharide-induced transcription of the IL-1beta promoter through direct interaction with the nuclear factor of interleukin 6 (NF-IL6, also known as CCAAT enhancer binding protein (C/EBPbeta), an essential regulator in IL-1beta transcription. We show for the first time that HSF1 binds directly to NF-IL6 in vivo and antagonizes its activity. The HSF1/NF-IL6 interaction involves a sequence of HSF1 containing the trimerization and regulatory domains and the bZip region of NF-IL6. HSF1 has little effect on IL-1beta promoter activity stimulated by the essential monocytic transcription factor Spi.1 but is strongly inhibitory to transcriptional activation by NF-IL6 and to the synergistic activation by NF-IL6 and Spi.1. Because of its ability to bind to specific C/EBP elements in the promoters of multiple genes and its ability to interact with other transcription factors, NF-IL6 is involved in transcriptional regulation of a wide range of genes. Interaction between HSF1 and NF-IL6 could thus be an important mechanism in HSF1 regulation of general gene transcription during endotoxin stress.
Xie
Yue
Y
Department of Radiation Oncology, Dana Farber Cancer Institute, Harvard Medical School, Beth Israel and Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115, USA.
Chen
Changmin
C
Stevenson
Mary Ann
MA
Auron
Philip E
PE
Calderwood
Stuart K
SK
D000818:Animals; D001665:Binding Sites; D015153:Blotting, Western; D016466:CHO Cells; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D006224:Cricetinae; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism*; D004731:Endotoxins / Q000494:pharmacology; D017930:Genes, Reporter; D005982:Glutathione Transferase / Q000378:metabolism; D006367:HeLa Cells; D000076249:Heat Shock Transcription Factors; D006801:Humans; D007375:Interleukin-1 / Q000235:genetics* / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008954:Models, Biological; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D014176:Protein Biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014157:Transcription Factors; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014162:Transfection
D004268:DNA-Binding Proteins; D004731:Endotoxins; C000619706:HSF1 protein, human; D000076249:Heat Shock Transcription Factors; D007375:Interleukin-1; D015850:Interleukin-6; D008070:Lipopolysaccharides; D014157:Transcription Factors; D005982:Glutathione Transferase