Figure 6: ER ligands modify AF-2 surface conformations in subtype-specific manners. A) M421 (ERα, H8) is flexible and reorients to accommodate the bulky ligand ferutinine (gray). H12 conformation remains unperturbed compared to estradiol-bound ERα (green). B) ERβ substituent I373 is less flexible than M421 of ERα, restricting the ability of the LBP to accommodate bulky ligands. This would potentially result in a shift of the ligand towards H12 and alteration of H12 conformation in ERβ (magenta) compared to ERα (gray), as observed.