X-Ray Crystal Structure of the Ancestral 3-Ketosteroid Receptor–Progesterone–Mifepristone Complex Shows Mifepristone Bound at the Coactivator Binding Interface
Figure 3
Fo-Fc electron density (green) contoured to 2 σ showing evidence for bound ligand. Omit maps were generated by removal of the ligand from the structure and running 3 cycles of gradient energy minimization and B-factor optimization in PHENIX (version dev-1423) to minimize model bias. A. Electron density within the LBP corresponding to the volume of progesterone. B. Electron density at the base of the receptor corresponding to the volume of mifepristone (site-one). C. Electron density at the coactivator cleft corresponding to the volume of mifepristone (site-two).