| RRC ID |
43121
|
| 著者 |
Yoshimura K, Muto Y, Shimizu M, Matsushima-Nishiwaki R, Okuno M, Takano Y, Tsurumi H, Kojima S, Okano Y, Moriwaki H.
|
| タイトル |
Phosphorylated retinoid X receptor alpha loses its heterodimeric activity with retinoic acid receptor beta.
|
| ジャーナル |
Cancer Sci
|
| Abstract |
A malfunction in retinoid X receptor (RXR) alpha due to phosphorylation is associated with the development of hepatocellular carcinoma. However, the precise mechanisms by which phosphorylated RXRalpha loses its physiological function remain unclear. In the present study we examined whether phosphorylation of RXRalpha affects its dimeric activity. Fluorescence resonance energy transfer studies and immunoprecipitation assays showed that the physical interaction between RXRalpha and retinoic acid receptor beta was impaired when 293T cells were transfected with phosphomimic mutant RXRalpha (T82D/S260D), whereas this interaction was activated at a level similar to wild-type RXRalpha-transfected cells when the cells were transfected with an unphosphorylated mutant RXRalpha (T82A/S260A). Treating the T82A/S260A-transfected cells with retinoid resulted in a significant increase in the transcriptional activities of the retinoic acid receptor responsive element and RXR responsive element promoters, whereas these transcriptional activities did not increase in the T82D/S260D-transfected cells. Transfection with T82A/S260A enhanced both the inhibition of cell growth and the induction of apoptosis caused by retinoid, although the T82D/S260D-transfected cells lost their responsiveness to retinoid. Moreover, transfection with T82A/S260A caused an inhibition of cell growth and a reduction of colony-forming ability in soft agar in HuH7 human hepatocellular carcinoma cells. These findings suggest that phosphorylation of RXRalpha abolishes its ability to form homodimers and heterodimers with RXR and retinoic acid receptor beta, thus resulting in the loss of cell growth control and the acceleration of cancer development. In conclusion, the inhibition of RXRalpha phosphorylation and the restoration of its original function as a master regulator of nuclear receptors might therefore be an effective strategy for controlling cancer cell growth.
|
| 巻・号 |
98(12)
|
| ページ |
1868-74
|
| 公開日 |
2007-12-1
|
| DOI |
10.1111/j.1349-7006.2007.00621.x
|
| PII |
CAS621
|
| PMID |
17900311
|
| MeSH |
Apoptosis
Cell Division
Cell Line
Dimerization
Fluorescence Resonance Energy Transfer
Gene Expression Regulation
Genes, Reporter
Humans
Kidney
Phosphorylation
Plasmids
Receptors, Retinoic Acid / genetics*
Receptors, Retinoic Acid / metabolism
Restriction Mapping
Retinoic Acid Receptor alpha
Retinoid X Receptor alpha / genetics*
Retinoid X Receptor alpha / metabolism
Transfection
|
| IF |
4.966
|
| 引用数 |
23
|
|
WOS 分野
|
ONCOLOGY
|
| リソース情報 |
| ヒト・動物細胞 |
|
