Abstract | AIM: Parkin has been shown to exert protective effects against 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in different models of Parkinson disease. In the present study we investigated the molecular mechanisms underlying the neuroprotective action of parkin in vitro. METHODS: HEK293, HeLa and PC12 cells were transfected with parkin, parkin mutants, p62 or si-p62. Protein expression and ubiquitination were assessed using immunoblot analysis. Immunoprecipitation assay was performed to identify the interaction between parkin and scaffold protein p62. PC12 and SH-SY5Y cells were treated with 6-OHDA (200 μmol/L), and cell apoptosis was detected using PI and Hoechst staining. RESULTS: In HEK293 cells co-transfected with parkin and p62, parkin was co-immunoprecipitated with p62, and parkin overexpression increased p62 protein levels. In parkin-deficient HeLa cells, transfection with wild-type pakin, but not with ligase activity-deficient pakin mutants, significantly increased p62 levels, suggesting that parkin stabilized p62 through its E3 ligase activity. Transfection with parkin or p62 significantly repressed ERK1/2 phosphorylation in HeLa cells, but transfection with parkin did not repress ERK1/2 phosphorylation in p62-knockdown HeLa cells, suggesting that p62 was involved in parkin-induced inhibition on ERK1/2 phosphorylation. Overexpression of parkin or p62 significantly repressed 6-OHDA-induced ERK1/2 phosphorylation in PC12 cells, and parkin overexpression inhibited 6-OHDA-induced apoptosis in PC12 and SH-SY5Y cells. CONCLUSION: Parkin protects PC12 cells against 6-OHDA-induced apoptosis via ubiquitinating and stabilizing scaffold protein p62, and repressing ERK1/2 activation.
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Authors | Xiao-ou Hou, Jian-min Si, Hai-gang Ren, Dong Chen, Hong-feng Wang, Zheng Ying, Qing-song Hu, Feng Gao, Guang-hui Wang |
Journal | Acta pharmacologica Sinica
(Acta Pharmacol Sin)
Vol. 36
Issue 11
Pg. 1300-7
(Nov 2015)
ISSN: 1745-7254 [Electronic] United States |
PMID | 26364802
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Heat-Shock Proteins
- Sequestosome-1 Protein
- Sqstm1 protein, rat
- Oxidopamine
- Ubiquitin-Protein Ligases
- parkin protein
- Mitogen-Activated Protein Kinase 1
- Mitogen-Activated Protein Kinase 3
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Topics |
- Animals
- Apoptosis
- HEK293 Cells
- HeLa Cells
- Heat-Shock Proteins
(metabolism)
- Humans
- Mitogen-Activated Protein Kinase 1
(metabolism)
- Mitogen-Activated Protein Kinase 3
(metabolism)
- Oxidopamine
(metabolism)
- PC12 Cells
- Rats
- Sequestosome-1 Protein
- Ubiquitin-Protein Ligases
(metabolism)
- Ubiquitination
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