NF-kappaB- and c-Jun-dependent regulation of human cytomegalovirus immediate-early gene enhancer/promoter in response to lipopolysaccharide and bacterial CpG-oligodeoxynucleotides in macrophage cell line RAW 264.7.
The cytomegalovirus immediate-early (CMV IE) gene enhancer/promoter regulates the expression of immediate-early gene products and initiation of CMV replication. TNF-alpha and lipopolysaccharide (LPS) strongly activate the promoter, possibly involving NF-kappaB. CpG-oligodeoxynucleotides (CpG-ODNs), which contain unmethylated CpG dinucleotides in the context of particular base sequences, have gained attention because of their stimulating effects, via NF-kappaB, which have a strong innate immune response. To study the effects of LPS and CpG-ODNs, as well as the mechanisms of their actions regarding CMV IE enhancer/promoter activation, we used a macrophage cell line, RAW 264.7. Stimulation of the cells with LPS or CpG-ODNs resulted in the activation of the CMV IE enhancer/promoter. We examined the involvement of NF-kappaB and c-Jun transcription factors by promoter deletion/site-specific mutation analysis and ectopic expression, and found them to have additive effects. Involvement of myeloid differentiation protein, an upstream regulator of NF-kappaB and c-Jun, was also investigated. Experimental results indicate that both LPS-induced and CpG-ODN-induced activations of CMV IE enhancer/promoter are mediated by Toll-like receptor signaling molecules. Several lines of evidence suggest the potential contribution of bacterial infection in CMV reactivation along with the potential application of CpG-ODNs in gene therapy as a stimulator for the optimal expression of target genes under the control of the CMV IE enhancer/promoter.
Cell Biology Laboratory, Korea Research Institute of Bioscience and Biotechnology, Yusong, Daejon, Korea.
Younghee
Y
Lee
Wern-Joo
WJ
Sohn
Doo-Sik
DS
Kim
Hyung-Joo
HJ
Kwon
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D000943:Antigens, Differentiation / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D003587:Cytomegalovirus / Q000187:drug effects / Q000235:genetics*; D004742:Enhancer Elements, Genetic / Q000187:drug effects / Q000235:genetics; D017781:Genes, Immediate-Early / Q000187:drug effects* / Q000235:genetics; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D053594:Myeloid Differentiation Factor 88; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D009838:Oligodeoxyribonucleotides / Q000494:pharmacology*; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000187:drug effects / Q000235:genetics; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion / Q000235:genetics; D051996:Transcription Factor RelA; D014162:Transfection
D048868:Adaptor Proteins, Signal Transducing; D000943:Antigens, Differentiation; C408982:CPG-oligonucleotide; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides; C507779:MYD88 protein, human; C507780:Myd88 protein, mouse; D053594:Myeloid Differentiation Factor 88; D016328:NF-kappa B; C000606204:NFKBIA protein, human; C000606205:Nfkbia protein, mouse; D009838:Oligodeoxyribonucleotides; D016755:Proto-Oncogene Proteins c-jun; D011971:Receptors, Immunologic; D051996:Transcription Factor RelA; D000072000:NF-KappaB Inhibitor alpha