Figure 2.

ABCA13 triggers cholesterol accumulation in intracellular vesicles. A, HEK293 cells transiently transfected with ABCA13 were labeled with anti-ABCA13 antibody (green) and the fluorescent cholesterol-binding probe filipin (magenta) after fixation and permeabilization. B, HEK293 cells transiently transfected with ABCA13 were labeled with anti-ABCA13 antibody (magenta) and the fluorescent probe EGFP-D4 targeting cholesterol-rich membrane domains (green) after fixation and permeabilization. Nuclei were stained with TOTO-3 (blue). C, the relative fluorescence intensity of EGFP-D4 signals in individual cells was quantified using ImageJ and shown as means + S.E.M. (mock, n = 8; ABCA13, n = 10). ∗∗p < 0.01. D, U2OS cells, a human osteosarcoma cell line, were fixed and labeled with anti-ABCA13 antibody (green) and filipin (magenta). Nuclei were stained with propidium iodide (blue). The bottom figures are higher magnification images of the area outlined in yellow. Scale bars represent 10 μm.