FIGURE 3.

Ent-cholesterol causes degradation of squalene monooxygenase. A, SRD-1 cells were pretreated with statin and then incubated with 20 μg/ml nat-cholesterol or ent-cholesterol in medium containing cycloheximide (10 μg/ml) for 8 h. Nontreated and CD-treated conditions served as controls. B, CHO-7 cells were transfected with 1 μg of pTK-SM-V5 for 24 h. Cells were pretreated with statin and then treated as in A. A and B, cell lysates were subjected to 10% SDS-PAGE and immunoblotted with anti-SQLE for endogenous SM (A) or anti-V5 for ectopic SM (B). Densitometric values of SM were expressed relative to the nontreated condition, which was set to 1 (n ≥ 4, ±S.E. (error bars)). *, p ≤ 0.05 for ent-cholesterol versus nontreated condition; **, p ≤ 0.01 for nat-cholesterol versus nontreated condition.