Fig. 6.

The LXR-IDOL degradation pathway targets a lipid-raft resident LDLR pool. HepG2 cells were cultured in FBS-containing medium and treated with vehicle (A) or 1 μM GW3965 for 4 h (B). Membrane fractions were isolated and an equal amount of protein per fraction was separated by SDS-PAGE and immunoblotted as indicated. Immunoblots are representative of two independent experiments with similar results. C: HepG2 and A431 cells were incubated for 16 h with sterol-depletion medium and subsequently pretreated with 1 μM GW3965 (GW; +) or vehicle (−) for 30 min followed by addition of 5 mg/ml MβCD for an additional 4 h. D: HepG2 cells were cultured as in (C) except that 10 μg/ml filipin was added for an additional 3 h. Total cell lysates were immunoblotted as indicated.