Figure 4.
Two views of a density feature assigned to cholesterol. The red density is contoured at 3.2σ, and the blue density at 1σ. (A) Side view, showing cholesterol, helix 4 of one rhodopsin molecule (with Trp161) and helices 5, 6 (with Trp265) and 7 of the adjacent rhodopsin molecule. These two molecules face in opposite directions: the extracellular side of the molecule on the left and the cytoplasmic side of the molecule on the right are towards the bottom of the page. (B) Top view, showing cholesterol sitting in a pocket between the two rhodopsin molecules.