Figure 5.

PM-IDE activity in vitro is impaired after manipulation of membrane lipid composition. A- Representative western blotting of IDE and flotillin-1 showed no differences in the protein levels in membranes isolated from control (CTL) and Mβ CD-treated cells.B- Representative PhosphorImage scan showed degradation of [¹²⁵I]-insulin after incubation with membranes isolated from cells treated or not with Mβ CD in the presence of a protease inhibitor cocktail (as described in Antibodies and Chemicals) with or without metalloprotease inhibitors (1,10 phenantroline/EDTA). Bars showed the semi-quantitative analysis of the percentage of [¹²⁵I]-insulin degradation by endogenous IDE from control and MβCD-treated membranes (n = 3; *p < 0.05).