GPER and ERalpha docking simulations. (a-b) The three-dimensional model of ERalpha is schematically reported as a light blue ribbon cartoon; residues involved in ligand binding are drawn as sticks. (a) The binding modes of E2 (pink sticks) to ERalpha in the "closed conformation" is shown. (b) The MIBE moiety (orange sticks) is drawn in its favorable conformation bound to ERalpha (open conformation), with the helix 12 displaced with respect to the position exhibited in the ERalpha-E2 complex. (c-d) The GPER model is reported as green ribbon and residues involved in ligand binding are drawn as sticks. (c) G-1 is drawn in yellow. (d) The MIBE moiety is drawn as orange sticks.