Modulation of the DNA binding activity of transcription factors CREP, NFkappaB and HSF by H2O2 and TNF alpha. Differences between in vivo and in vitro effects.
Human endothelial cells exposed to H2O2 showed reduced CREP DNA binding activity, enhanced HSF activation, and no induction of NFkappaB binding activity. Interestingly, H2O2 was able to induce NFkappaB subunit p65 translocation in the nucleus. In contrast, cells exposed to TNF alpha showed enhanced CREP binding activity, activation of NFkappaB and no induction of HSE-HSF complex. Addition of H2O2, diamide and iodoacetic acid to the binding reaction mixture markedly reduced the DNA binding ability of the three transcription factors. Thus free sulfhydryls were important in DNA binding activity of CREP, NFkappaB and HSF, and the lack of induction of NFkappaB by H2O2 in intact cells was likely caused by oxidation on a thiol, and not by a deficiency in the activation pathway.
Jornot
L
L
Department of Internal Medicine, University Hospital, Geneva, Switzerland.
Petersen
H
H
Junod
A F
AF
D002478:Cells, Cultured; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003958:Diamide / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007461:Iodoacetates / Q000494:pharmacology; D019807:Iodoacetic Acid; D007700:Kinetics; D016328:NF-kappa B / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014471:Umbilical Veins
D017362:Cyclic AMP Response Element-Binding Protein; D004268:DNA-Binding Proteins; D006360:Heat-Shock Proteins; D007461:Iodoacetates; D016328:NF-kappa B; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D003958:Diamide; D004247:DNA; D006861:Hydrogen Peroxide; D019807:Iodoacetic Acid