Figure 2.

The two cholesterol-binding sites identified on the agonist-free β₂ adrenergic receptor. (A and B) The TM surface with surface pockets identified using CASTp (20) is shown, colored from most hydrophobic (orange) to most hydrophilic (blue), (A) without and (B) with a cholesterol molecule (green spheres) bound to Gly320. (C) An expanded view of the cholesterol binding pocket (cholesterol in ball and stick representation) is shown. (D) The TM surface with a cholesterol molecule bound to Ser161 is shown. To see this figure in color, go online.