Loading...
|
Please use this identifier to cite or link to this item:
https://ir.csmu.edu.tw:8080/ir/handle/310902500/11809
|
Title: | MCRS2 represses the transactivation activities of Nrf1 |
Authors: | Wu, Jia-Long Lin, Young-Sun Yang, Chi-Chiang Lin, Yu-Jen Wu, Shan-Fu Lin, Ying-Ting Huang, Chien-Fu |
Contributors: | 中山醫學大學 |
Date: | 2009 |
Issue Date: | 2015-07-29T09:25:08Z (UTC)
|
ISSN: | 1471-2121 |
Abstract: | Background
Nrf1 [p45 nuclear factor-erythroid 2 (p45 NF-E2)-related factor 1], a member of the CNC-bZIP (CNC basic region leucine zipper) family, is known to be a transcriptional activator by dimerization with distinct partners, such as Maf, FosB, c-Jun, JunD, etc. The transcriptional roles of CNC-bZIP family are demonstrated to be involved in globin gene expression as well as the antioxidant response. For example, CNC-bZIP factors can regulate the expression of detoxification proteins through AREs, such as expression of human gamma-glutamylcysteine synthetases (GCS), glutathione S-transferases (GST), UDP-glucuronosyl transferase (UDP-GT), NADP (H) quinone oxidoreductase (NQOs), etc. To further explore other factor(s) in cells related to the function of Nrf1, we performed a yeast two-hybrid screening assay to identify any Nrf1-interacting proteins. In this study, we isolated a cDNA encoding residues 126–475 of MCRS2 from the HeLa cell cDNA library. Some functions of MCRS1 and its splice variant-MSP58 and MCRS2 have been previously identified, such as transforming, nucleolar sequestration, ribosomal gene regulation, telomerase inhibition activities, etc. Here, we demonstrated MCRS2 can function as a repressor on the Nrf1-mediated transactivation using both in vitro and in vivo systems.
Results
To find other proteins interacting with the CNC bZIP domain of Nrf1, the CNC-bZIP region of Nrf1 was used as a bait in a yeast two-hybrid screening assay. MCRS2, a splicing variant of p78/MCRS1, was isolated as the Nrf1-interacting partner from the screenings. The interaction between Nrf1 and MCRS2 was confirmed in vitro by GST pull-down assays and in vivo by co-immunoprecipitation. Further, the Nrf1-MCRS2 interaction domains were mapped to the residues 354–447 of Nrf1 as well as the residues 314–475 of MCRS2 respectively, by yeast two-hybrid and GST pull-down assays. By immunofluorescence, MCRS2-FLAG was shown to colocalize with HA-Nrf1 in the nucleus and didn't result in the redistribution of Nrf1. This suggested the existence of Nrf1-MCRS2 complex in vivo. To further confirm the biological function, a reporter driven by CNC-bZIP protein binding sites was also shown to be repressed by MCRS2 in a transient transfection assay. An artificial reporter gene activated by LexA-Nrf1 was also specifically repressed by MCRS2.
Conclusion
From the results, we showed MCRS2, a new Nrf1-interacting protein, has a repression effect on Nrf1-mediated transcriptional activation. This was the first ever identified repressor protein related to Nrf1 transactivation. |
URI: | https://ir.csmu.edu.tw:8080/ir/handle/310902500/11809 http://dx.doi.org/10.1186/1471-2121-10-9 |
Relation: | BMC Cell Biology 2009, 10:9 |
Appears in Collections: | [醫學檢驗暨生物技術學系暨碩士班] 期刊論文
|
Files in This Item:
File |
Description |
Size | Format | |
index.html | 期刊論文 | 0Kb | HTML | 335 | View/Open |
|
All items in CSMUIR are protected by copyright, with all rights reserved.
|