Obligatory role of cyclic adenosine monophosphate response element in cyclooxygenase-2 promoter induction and feedback regulation by inflammatory mediators.
BACKGROUND
Cyclooxygenase-2 (COX-2) plays a key role in human inflammatory disorders such as vascular inflammation. COX-2 promoter activity is induced by proinflammatory mediators, but the role of cyclic adenosine monophosphate response element (CRE) in promoter stimulation remains unclear.


RESULTS
Transient transfection of a 0.9-kb COX-2 promoter fragment bearing CRE mutation abrogated COX-2 promoter activity induced by proinflammatory mediators in human endothelial cells and fibroblasts. Dual mutations of CRE and an upstream CCAAT/enhancer binding protein (C/EBP) site did not have an additional effect. Binding of CREB-2, ATF-2, USF-2, and c-Jun transactivators to a wild-type and CRE-mutated oligonucleotide was analyzed by a novel DNA-binding assay. CREB-2 and ATF-2 in nuclear extracts of unstimulated endothelial cells bound to CRE, whereas USF-2 and c-Jun or c-Fos bound to non-CRE sites. CREB-2 and c-Fos binding was increased by phorbol 12-myristate 13-acetate but not tumor necrosis factor-alpha. The binding assay and chromatin immunoprecipitation revealed binding of P300 coactivator to the COX-2 promoter region.


CONCLUSIONS
CRE plays an obligatory role in COX-2 promoter activation by diverse stimuli. CREB-2 and ATF-2 bound to CRE serve as an anchor for P300 interaction with upstream transactivators and downstream transcription machinery.
Schroer
Karsten
K
Institut für Pharmakologie und Klinische Pharmakologie, Heinrich-Heine-Universtät Düsseldorf, Düsseldorf, Germany.
Zhu
Ying
Y
Saunders
Michael A
MA
Deng
Wu-Guo
WG
Xu
Xiao-Ming
XM
Meyer-Kirchrath
Jutta
J
Wu
Kenneth K
KK
D051701:Activating Transcription Factor 4; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D002843:Chromatin / Q000378:metabolism; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000378:metabolism; D051546:Cyclooxygenase 2; D004730:Endothelium, Vascular / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D004790:Enzyme Induction; D006801:Humans; D018836:Inflammation Mediators / Q000494:pharmacology*; D007375:Interleukin-1 / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics*; D008565:Membrane Proteins; D009687:Nuclear Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D011453:Prostaglandins / Q000494:pharmacology; D020218:Response Elements; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D015533:Transcriptional Activation; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation
C497109:ATF4 protein, human; D002843:Chromatin; D018836:Inflammation Mediators; D007375:Interleukin-1; D007527:Isoenzymes; D008565:Membrane Proteins; D009687:Nuclear Proteins; D011453:Prostaglandins; D015534:Trans-Activators; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D051701:Activating Transcription Factor 4; D000242:Cyclic AMP; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D013755:Tetradecanoylphorbol Acetate