Fluorescence spectroscopy studies of HEK293 cells expressing DOR-Gi1α fusion protein; the effect of cholesterol depletion

► Effect of cholesterol on the organization of plasma membranes and G protein activation. ► Cholesterol depletion increases membrane fluidity and mobility of plasma membranes. ► Cholesterol depletion does not alter the agonist binding site of δ-opioid receptor (DOR). ► Cholesterol depletion decreases the ability of DOR agonist to activate G proteins. ► Indication that biophysical state of membrane is a regulatory factor of DOR-signaling cascade.