title: Involvement of TNF and NF-kappa B in the transcriptional control of cyclooxygenase-2 expression by IFN-gamma in macrophages.
abstract: IFN-gamma induces cyclooxygenase (COX)-2 expression and PG production in mouse macrophage cells. IFN-gamma activates COX-2 promoter-driven transcription. Deletion of the IFN sequence regulatory element (ISRE) I -1541/-1522 and ISRE II -1215/-1206 sites of the mouse COX-2 promoter minimally decrease this IFN-gamma induction. In contrast, deletion of the -965/-150 region from the COX-2 promoter abrogated IFN-gamma induction. In this region a NF-kappaB site has been described and mutation of this site impairs the induction of the full COX-2 promoter by IFN-gamma. Moreover, IFN-gamma induction of the COX-2 promoter was also strongly reduced by transfection of plasmid encoding the NF-kappaB inhibitor, IkappaBalpha. Interestingly, IFN-gamma induction of the COX-2 and PGE(2) synthesis was absent in macrophages from TNF(-/-) mice, and neutralizing anti-TNF Abs inhibited COX-2 promoter induction by IFN-gamma in RAW 264.7 macrophages. Moreover, NF-kappaB activity was induced late after stimulation with IFN-gamma correlating with the effect of autocrine TNF, and this NF-kappaB activation was absent in macrophages from TNF(-/-) mice. Taken together our results suggest a model in which IFN-gamma-induced TNF activates NF-kappaB, which is required for full COX-2 expression.
authors.affiliation: Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma, Madrid, Spain.
authors.forename: Virginia
authors.initials: V
authors.lastname: Vila-del Sol
authors.forename: Manuel
authors.initials: M
authors.lastname: Fresno
mesh_terms: D000818:Animals; D002460:Cell Line; D051546:Cyclooxygenase 2; D004268:DNA-Binding Proteins / Q000235:genetics; D015232:Dinoprostone / Q000096:biosynthesis; D004790:Enzyme Induction / Q000235:genetics / Q000276:immunology; D015971:Gene Expression Regulation, Enzymologic / Q000276:immunology*; D050856:Interferon Regulatory Factor-1; D050836:Interferon Regulatory Factor-2; D007371:Interferon-gamma / Q000502:physiology*; D008264:Macrophages / Q000201:enzymology / Q000276:immunology*; D017737:Macrophages, Peritoneal / Q000201:enzymology / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016328:NF-kappa B / Q000502:physiology*; D010750:Phosphoproteins / Q000235:genetics; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis* / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D014158:Transcription, Genetic / Q000276:immunology*; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000172:deficiency / Q000235:genetics / Q000502:physiology*
chemical_list: D004268:DNA-Binding Proteins; D050856:Interferon Regulatory Factor-1; D050836:Interferon Regulatory Factor-2; C494258:Irf1 protein, mouse; C494230:Irf2 protein, mouse; D016328:NF-kappa B; D010750:Phosphoproteins; D012097:Repressor Proteins; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone