| Autor: |
Raspè E; UR 545 INSERM, Institut Pasteur de Lille, 1 Rue du Pr. Calmette, 59019 Lille, France., Mautino G, Duval C, Fontaine C, Duez H, Barbier O, Monte D, Fruchart J, Fruchart JC, Staels B |
| Jazyk: |
angličtina |
| Zdroj: |
The Journal of biological chemistry [J Biol Chem] 2002 Dec 20; Vol. 277 (51), pp. 49275-81. Date of Electronic Publication: 2002 Oct 10. |
| DOI: |
10.1074/jbc.M206215200 |
| Abstrakt: |
The Rev-erb and retinoic acid-related orphan receptors (ROR) are two related families of orphan nuclear receptors that recognize similar response elements but have opposite effects on transcription. Recently, the Rev-erbalpha gene promoter has been characterized and shown to harbor a functional Rev-erbalpha-binding site known as Rev-DR2, responsible for negative feedback down-regulation of promoter activity by Rev-erbalpha itself. The present study aimed to investigate whether Rev-erbalpha gene expression is regulated by RORalpha. Gel shift analysis demonstrated that in vitro translated hRORalpha1 protein binds to the Rev-DR2 site, both as monomer and dimer. Chromatin immunoprecipitation assays demonstrated that binding of RORalpha to this site also occurred in vivo in human hepatoma HepG2 cells. The Rev-DR2 site was further shown to be functional as it conferred hRORalpha1 responsiveness to a heterologous promoter and to the natural human Rev-erbalpha gene promoter in these cells. Mutation of this site in the context of the natural Rev-erbalpha gene promoter abolished its activation by RORalpha, indicating that this site plays a key role in hRORalpha1 action. Finally, adenoviral overexpression of hRORalpha1 in HepG2 cells led to enhanced hRev-erbalpha mRNA accumulation, further confirming the physiological importance of RORalpha1 in the regulation of Rev-erbalpha expression. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
|
