High level transactivation by a modified Bombyx ecdysone receptor in mammalian cells without exogenous retinoid X receptor
AUTOR(ES)
Suhr, Steven T.
FONTE
The National Academy of Sciences
RESUMO
Our studies of the Bombyx mori ecdysone receptor (BE) revealed that, unlike the Drosophila melanogaster ecdysone receptor (DE), treatment of BE with the ecdysone agonist tebufenozide stimulated high level transactivation in mammalian cells without adding an exogenous heterodimer partner. Gel mobility shift and transfection assays with both the ultraspiracle gene product (Usp) and retinoid X receptor heterodimer partners indicated that this property of BE stems from significantly augmented heterodimer complex formation and concomitant DNA binding. We have mapped this “gain of function” to determinants within the D and E domains of BE and demonstrated that, although the D domain determinant is sufficient for high affinity heterodimerization with Usp, both determinants are necessary for high affinity interaction with retinoid X receptor. Modified BE receptors alone used as replication-defective retroviruses potently stimulated separate “reporter” viruses in all cell types examined, suggesting that BE has potentially broad utility in the modulation of transgene expression in mammalian cells.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=20918Documentos Relacionados
- High level transactivation by the ecdysone receptor complex at the core recognition motif.
- The dual role of ultraspiracle, the Drosophila retinoid X receptor, in the ecdysone response
- Ecdysteroid-dependent regulation of genes in mammalian cells by a Drosophila ecdysone receptor and chimeric transactivators.
- Mouse retinoid X receptor contains a separable ligand-binding and transactivation domain in its E region.
- Efficient transactivation by retinoic acid receptors in yeast requires retinoid X receptors.