Fig. 2.

Binding sites for β₂-agonists revealed by crystal structures. (A) Crystal structures of human β₂AR in complex with epinephrine (Supplemental Material 1-PDB ID 4LDO), BI-167107 (Supplemental Material 1-PDB ID 4LDE), and salmeterol (Supplemental Material 1-PDB ID 6MXT). Polar interactions are shown as dashed lines. Residues in β₂AR that interact with each ligand are shown as sticks. (B) Exosite for the binding of the tail group of salmeterol in the crystal structure of human β₂AR with salmeterol (Supplemental Material 1-PDB ID 6MXT).