Figure 2

Clathrin and dynamin-2 mediate SR-AI-dependent oAβ internalization. A, SR-AI-transfected COS-7 cells were incubated with FAM-oAβ (green) and immunostained with anti-SR-A antibody (red). Representative confocal images showed the co-localization of FAM-oAβ and SR-AI in endocytotic vesicles (left panel). A magnified image of the boxed region was shown in the right panels. Scale bar, 10 μm. B, COS-7 cells were co-transfected with SR-AI and clathrin shRNA or luciferase shRNA (negative control). The confocal images and the quantification of clathrin immunoreactivity showed clathrin shRNA knockdown the expression of clatherin in SR-AI-positive cells. The experiments were repeated at least three times. C. The relative level of internalized oAβ was significantly reduced by clathrin shRNA compared with luciferase shRNA in SR-AI-positive cells. D, COS-7 cells were co-transfected with SR-AI and HA-tagged wild type dynamin-2 or dominant-negative dynamin-2 (K44A). The relative intensity of internalized oAβ was significantly reduced by dynamin-2 (K44A) in SR-AI-positive cells. More than 100 SR-AI-positive cells were analyzed. Bars indicate mean ± SEM of three independent experiments (*p < 0.05).