Critical role of C/EBPdelta and C/EBPbeta factors in the stimulation of the cyclooxygenase-2 gene transcription by interleukin-1beta in articular chondrocytes.
The activity of the [-831; +103] promoter of the human cyclooxygenase-2 gene in cultured rabbit chondrocytes is stimulated 2.9 +/- 0.3-fold by interleukin-1beta and this stimulation depends on [-132; -124] C/EBP binding-and [-223; -214] NF-kappaB binding-sites. The C/EBPbeta and C/EBPdelta factors bind to the [-132; -124] sequence. The [-61; -53] sequence is also recognized by C/EBPbeta and C/EBPdelta as well as USF. Mutation of the whole [-61; -53] sequence abolished the stimulation of transcription but single mutations of the C/EBP or USF site did not alter the activity of the promoter, suggesting that the factors bound to the proximal [-61; -53] sequence interact with different members of the general transcription machinery. The [-223; -214] site binds only the p50/p50 homodimer and a non-rel-related protein, but not the transcriptionally active heterodimer p50/p65. The p50/p50 homodimer could interact with the C/EBP family members bound to the [-132; -124] sequence for full stimulation of the COX-2 transcription by interleukin-1beta in chondrocytes. By contrast, the [-448; -449] sequence binds with a low affinity both the p50/p50 homodimeric and p50/p65 heterodimeric forms of NF-kappaB but has no role in the regulation of the human COX-2 promoter in chondrocytes.
Thomas
B
B
UPRES-A CNRS 7079, Université Pierre et Marie Curie, Paris, France.
Berenbaum
F
F
Humbert
L
L
Bian
H
H
Béréziat
G
G
Crofford
L
L
Olivier
J L
JL
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000502:physiology*; D051743:CCAAT-Enhancer-Binding Protein-delta; D022762:CCAAT-Enhancer-Binding Proteins / Q000502:physiology*; D002358:Cartilage, Articular / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D015500:Chloramphenicol O-Acetyltransferase / Q000378:metabolism; D019902:Chondrocytes / Q000378:metabolism*; D051546:Cyclooxygenase 2; D005260:Female; D017353:Gene Deletion; D005786:Gene Expression Regulation; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism*; D007527:Isoenzymes / Q000235:genetics*; D007700:Kinetics; D008565:Membrane Proteins; D008954:Models, Biological; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics*; D011485:Protein Binding; D020569:Proto-Oncogene Proteins c-rel / Q000378:metabolism; D011817:Rabbits; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors; D014158:Transcription, Genetic
D022782:CCAAT-Enhancer-Binding Protein-beta; D022762:CCAAT-Enhancer-Binding Proteins; C497252:CEBPD protein, human; D007375:Interleukin-1; D007527:Isoenzymes; D008565:Membrane Proteins; D020569:Proto-Oncogene Proteins c-rel; D014157:Transcription Factors; D051743:CCAAT-Enhancer-Binding Protein-delta; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; D015500:Chloramphenicol O-Acetyltransferase