Up-Regulation of Human Inducible Nitric Oxide Synthase by p300 Transcriptional Complex
| Autor: | Liang Zheng, Xinghua Liao, Zhong Guo, David A. Geller |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Chromatin Immunoprecipitation Proto-Oncogene Proteins c-jun Interleukin-1beta Nitric Oxide Synthase Type II lcsh:Medicine Fos-Related Antigen-2 P300-CBP Transcription Factors Biology Gene Expression Regulation Enzymologic Interferon-gamma 03 medical and health sciences Transactivation Genes Reporter Transcription (biology) Cell Line Tumor Coactivator Humans p300-CBP Transcription Factors Promoter Regions Genetic lcsh:Science Enhancer Transcription factor Binding Sites Multidisciplinary 030102 biochemistry & molecular biology Tumor Necrosis Factor-alpha Gene Expression Profiling lcsh:R NF-kappa B Promoter Molecular biology Recombinant Proteins Up-Regulation Transcription Factor AP-1 030104 developmental biology Mutagenesis Transcription Coactivator Mutagenesis Site-Directed Cytokines lcsh:Q E1A-Associated p300 Protein Research Article Protein Binding |
| Zdroj: | PLoS ONE, Vol 11, Iss 1, p e0146640 (2016) PLoS ONE |
| ISSN: | 1932-6203 |
| Popis: | p300, a ubiquitous transcription coactivator, plays an important role in gene activation. Our previous work demonstrated that human inducible nitric oxide synthase (hiNOS) expression can be highly induced with the cytokine mixture (CM) of TNF-α + IL-1β + IFN-γ. In this study, we investigated the functional role of p300 in the regulation of hiNOS gene expression. Our initial data showed that overexpression of p300 significantly increased the basal and cytokine-induced hiNOS promoter activities in A549 cells. Interestingly, p300 activated cytokine-induced hiNOS transcriptional activity was completely abrogated by deleting the upstream hiNOS enhancer at -5 kb to -6 kb in the promoter. Furthermore, p300 over-expression increased cytokine-induced transcriptional activity on a heterologous minimal TK promoter with the same hiNOS enhancer. Site-directed mutagenesis of the hiNOS AP-1 motifs revealed that an intact upstream (-5.3 kb) AP-1 binding site was critical for p300 mediated cytokine-induced hiNOS transcription. Furthermore, our ChIP analysis demonstrated that p300 was binding to Jun D and Fra-2 proteins at -5.3 kb AP-1 binding site in vivo. Lastly, our 3C assay was able to detect a long DNA loop between the hiNOS enhancer and core promoter site, and ChIP loop assay confirmed that p300 binds to AP-1 and RNA pol II proteins. Overall, our results suggest that coactivator p300 mediates cytokine-induced hiNOS transactivation by forming a distant DNA loop between its enhancer and core promoter region. |
| Databáze: | OpenAIRE |
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