Unprecedented conformational flexibility revealed in the ligand-binding domains of the Bovicola ovis ecdysone receptor (EcR) and ultraspiracle (USP) subunits.

摘要: The heterodimeric ligand-binding region of the Bovicola ovis ecdysone receptor has been crystallized either in presence an ecdysteroid or a synthetic methylene lactam insecticide. Two X-ray crystallographic structures, determined at 2.7 A resolution, show that domains both subunits this receptor, like those other nuclear receptors, can display significant conformational flexibility. Thermal melt experiments while ponasterone A stabilizes higher order structure heterodimer solution, destabilizes it. conformations EcR and USP observed have not seen previously any represent new level flexibility for these important receptors. Interestingly, conformation presents open, unoccupied pocket.