論文 - 詳細
| RRC ID | 38550 |
|---|---|
| 著者 | Yaguchi T, Nakano T, Gotoh A, Nishizaki T. |
| タイトル | Adenosine promotes GATA-2-regulated p53 gene transcription to induce HepG2 cell apoptosis. |
| ジャーナル | Cell Physiol Biochem |
| Abstract |
BACKGROUND/AIMS:In our earlier study, adenosine induced apoptosis in HepG2 human hepatoma cells by tuning of apoptosis-mediator gene transcription. The present study aimed at understanding the regulatory mechanism underlying the apoptosis-mediator gene transcription under the control of adenosine. METHODS:For HepG2 cells with and without knocking-down p53 or GATA-2, cell viability, mitochondrial membrane potentials, caspase activity, and transcriptional activity were monitored, and Western blotting, RT-PCR, electrophoretic mobility shift assay (EMSA), and chromatin immunoprecipitation (ChIP) assay were carried out. RESULTS:Extracellular adenosine upregulated expression of the p53 mRNA and protein in HepG2 human hepatoma cells. Adenosine induced apoptosis, disrupted mitochondrial membrane potentials, and activated caspase-3, -8 and -9 in HepG2 cells, and those effects were inhibited by silencing the p53-targetd gene. In the assay of transcriptional activity using full-length p53 gene promoter and 5' deletion mutants combined with the luciferase reporter vector, adenosine enhanced transcriptional activity for full-length p53 gene promoter, that was prevented by deleting from -240 to -146 bp on the promoter. In the EMSA using a (32)P-labeled DNA probe to detect binding to the putative GATA-2 biding site on the p53 gene promoter, adenosine produced (32)P-positive signals in nuclear extracts from HepG2 cells. In the Western blot analysis, adenosine increased presence of GATA-2 in nuclear extracts. In the ChIP assay, adenosine increased PCR products for the p53 gene promoter in chromosomal extracts from HepG2 cells, immunoprecipitated using an anti-GATA-2 antibody. Adenosine-induced upregulation of the p53 mRNA expression was suppressed by knocking-down GATA-2. CONCLUSION:The results of the present study show that p53 is a transcriptional target of GATA-2 and that adenosine upregulates GATA-2-regulated p53 expression, thereby activating caspase-3, -8, and -9 to induce HepG2 cell apoptosis. |
| 巻・号 | 28(4) |
| ページ | 761-70 |
| 公開日 | 2011-1-1 |
| DOI | 10.1159/000335770 |
| PII | 000335770 |
| PMID | 22178888 |
| MeSH | Adenosine / pharmacology* Apoptosis* / drug effects Binding Sites Caspase 3 / metabolism Caspase 8 / metabolism Caspase 9 / metabolism Chromatin Immunoprecipitation Electrophoretic Mobility Shift Assay GATA2 Transcription Factor / antagonists & inhibitors GATA2 Transcription Factor / genetics GATA2 Transcription Factor / metabolism* Gene Deletion Gene Expression Regulation / drug effects* Hep G2 Cells Humans Membrane Potential, Mitochondrial / drug effects Promoter Regions, Genetic RNA Interference RNA, Small Interfering / metabolism Tumor Suppressor Protein p53 / antagonists & inhibitors Tumor Suppressor Protein p53 / genetics Tumor Suppressor Protein p53 / metabolism* |
| IF | 5.5 |
| 引用数 | 5 |
| WOS 分野 | PHYSIOLOGY CELL BIOLOGY |
| リソース情報 | |
| ヒト・動物細胞 | Hep G2(RCB1648) |