The nuclear factor-kappaB engages CBP/p300 and histone acetyltransferase activity for transcriptional activation of the interleukin-6 gene promoter.
Expression of the pleiotropic cytokine interleukin (IL)-6 can be stimulated by the proinflammatory cytokine tumor necrosis factor (TNF) and the microbial alkaloid staurosporine (STS). In this report, the transcriptional mechanisms were thoroughly investigated. Whereas transcription factors binding to the activator protein-1-, cAMP-responsive element-, and CAAT enhancer-binding protein-responsive sequences are necessary for gene activation by STS, nuclear factor (NF)-kappaB alone is responsible and sufficient for inducibility by TNF, which reveals distinct signaling pathways for both compounds. At the cofactor level, cAMP-responsive element-binding protein-binding protein (CBP) or p300 potentiate basal and induced IL-6 promoter activation via multiple protein-protein interactions with all transcription factors bound to the promoter DNA. However, the strongest promoter activation relies on the p65 NF-kappaB subunit, which specifically engages CBP/p300 for maximal transcriptional stimulation by its histone acetyltransferase activity. Moreover, treatment of chromatin-integrated promoter constructions with the histone deacetylase inhibitor trichostatin A exclusively potentiates TNF-dependent (i.e. NF-kappaB-mediated) gene activation, while basal or STS-stimulated IL-6 promoter activity remains completely unchanged. Similar observations were recorded with other natural NF-kappaB-driven promoters, namely IL-8 and endothelial leukocyte adhesion molecule (ELAM). We conclude that, within an "enhanceosome-like" structure, NF-kappaB is the central mediator of TNF-induced IL-6 gene expression, involving CBP/p300 and requiring histone acetyltransferase activity.
Vanden Berghe
W
W
Department of Molecular Biology, University of Gent and Flanders Interuniversity Institute for Biotechnology, B-9000 Gent, Belgium.
De Bosscher
K
K
Boone
E
E
Plaisance
S
S
Haegeman
G
G
D000123:Acetyltransferases / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D050881:E1A-Associated p300 Protein; D051548:Histone Acetyltransferases; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D015850:Interleukin-6 / Q000235:genetics*; D051379:Mice; D016328:NF-kappa B / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D029701:Saccharomyces cerevisiae Proteins; D019311:Staurosporine / Q000494:pharmacology; D015534:Trans-Activators / Q000378:metabolism*; D015533:Transcriptional Activation / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D006877:Hydroxamic Acids; D015850:Interleukin-6; D016328:NF-kappa B; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014409:Tumor Necrosis Factor-alpha; C012589:trichostatin A; D000123:Acetyltransferases; D050881:E1A-Associated p300 Protein; C494361:Ep300 protein, mouse; D051548:Histone Acetyltransferases; D019311:Staurosporine