Fig. 3
From: Advances in the allostery of angiotensin II type 1 receptor
Comparison of the allosteric structures of human AT1R bound to different ligands. A Overall conformational changes in human AT1R with blocker ZD7155 (PDB ID: 4YAY, green), β-arrestin biased ligand TRV026 (PDB ID: 60S2, yellow) and endogenous agonist AngII (PDB ID: 6OS0, pink). In the active state, TM5 and TM6 move out of AT1R whereas TM7 moves inward of the receptor. Helix 8 adopts a position parallel to the membrane compared to the inactive conformation bent away from the membrane. Viewing from the extracellular side, TM5 and TM7 move inward of inactive AT1R. B Superimposed structural details of AT1R induced by different ligands. The bulky phenylalanine of AngII at position 8 pushes L1123.36 inward and Y2927.43 in a relocation. A hydrogen bond between N2957.46 and N1113.35 breaks, and the two residuces move inward. However, due to TRV026 being less deeply into the binding pocket of AT1R, it has very little effect on movement of these residuces except for N2957.46. C The alternative conformation is chosen when TM7 points toward TM3, and the canonical active conformation is chosen when TM7 points toward TM2.