Functional interaction between cyclooxygenase-2 and p53 in response to an endogenous electrophile
| Autor: | Fumie Nakashima, Koji Uchida, Miho Chikazawa, Nao Matsukawa, Noriko Noguchi, Takahiro Shibata, Hiroko Usami, Takeshi Kumagai |
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| Rok vydání: | 2015 |
| Předmět: |
p53
Proteasome Endopeptidase Complex RT-PCR reverse transcription-polymerase chain reaction Lipid peroxidation Clinical Biochemistry Endogeny Biology p38 Mitogen-Activated Protein Kinases Biochemistry Gene Expression Regulation Enzymologic Cell Line Sp1 Gene expression Animals RNA Messenger Protein kinase A lcsh:QH301-705.5 Transcription factor Oligonucleotide Array Sequence Analysis Aldehydes lcsh:R5-920 Sp1 transcription factor Arachidonic Acid Proteasome Organic Chemistry Epithelial Cells HNE 4-hydroxy-2-nonenal Transfection Molecular biology EMSAs electrophoretic movility shift assays Rats Cyclooxygenase lcsh:Biology (General) GAPDH glyceraldehyde-3-phosphate dehydrogenase Cyclooxygenase 2 Prostaglandins Cox cyclooxygenase 4-Hydroxy-2-nonenal TTBS tween 20/tris buffered saline RIPA radioimmunoprecipitation assay Tumor Suppressor Protein p53 Signal transduction lcsh:Medicine (General) MAPK mitogen-activated protein kinase Research Paper Signal Transduction |
| Zdroj: | Redox Biology, Vol 4, Iss C, Pp 74-86 (2015) Redox Biology |
| ISSN: | 2213-2317 |
| DOI: | 10.1016/j.redox.2014.11.011 |
| Popis: | Cyclooxygenase-2 (Cox-2) is rapidly expressed by various stimuli and plays a key role in conversion of free arachidonic acid to prostaglandins. We have previously identified 4-hydroxy-2-nonenal (HNE), a lipid peroxidation-derived electrophile, as the potent Cox-2 inducer in rat epithelial RL34 cells and revealed that the HNE-induced Cox-2 expression resulted from the stabilization of Cox-2 mRNA that is mediated by the p38 mitogen-activated protein kinase signaling pathway. In the present study, we investigated an alternative regulatory mechanism of Cox-2 expression mediated by a transcription factor p53. In addition, to characterize the causal role for Cox-2, we examined the effects of Cox-2 overexpression in RL34 cells. To examine whether the HNE-induced Cox-2 expression was mechanistically linked to the p53 expression, we analyzed changes in Cox-2 and p53 expression levels in response to HNE and observed that the Cox-2 levels were inversely correlated with the p53 levels. Down-regulation of p53 followed by the activation of a transcription factor Sp1 was suggested to be involved in the HNE-induced Cox-2 gene expression. To characterize the effect of Cox-2 expression in the cells, we established the Cox-2-overexpressing derivatives of RL34 cells by stable transfection with Cox-2 cDNA. An oligonucleotide microarray analysis revealed a dramatic down-regulation of the proteasome subunit RC1 in the Cox-2 overexpressed cells compared to the empty-vector transfected control cells. Consistent with the Cox-2-mediated down-regulation of proteasome, a moderate reduction of the proteasome activities was observed. This proteasome dysfunction mediated by the Cox-2 overproduction was associated with the enhanced accumulation of p53 and ubiquitinated proteins, leading to the enhanced sensitivity toward electrophiles. These results suggest the existence of a causal link between Cox-2 and p53, which may represent a toxic mechanism of electrophilic lipid peroxidation products. |
| Databáze: | OpenAIRE |
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