Fig. 5

LONP2 knockdown induced lipid storage, including aberrant cholesterol accumulation in lysosomes. a Representative confocal images (left) and quantification (right) of lipid droplets (Nile Red) in NT- and LONP2-silenced COS-7 cells after 6 days. Scale bar, 5 µm. b Representative confocal images showing the Filipin-stained intracellular cholesterol (green), Nile Red-stained lipid droplets (magenta) and endolysosomes (blue) visualized with the immunofluorescence of LAMP1. Scale bar, 2 µm. c, d Free cholesterol overload experiment in NT- and LONP2-silenced COS-7 cells (c) and U2OS cells (d) after 7 days. Representative confocal images (left) and quantifications (right) of the colocalization between cholesterol (Filipin) and endolysosomes (LAMP1). Scale bar, 2 µm. e Transmission electron microscopy micrographs of NT- and LONP2-silenced COS-7 cells. Scale bar, 500 nm. f Immunoblotting (left) and image quantification (right) of cholesterol overload experiment in NT- and LONP2-silenced COS-7 cells rescued with transient expression of siRNA-resistant LONP2 cDNA for 48 h. Data from n = 3 technically independent experiments, and their respective means are depicted in different colours. The mean values were used to calculate the average (horizontal bar), s.d. (error bars) and P-values (using a two-tailed unpaired Student’s t-test)