Figure 3.

TPC1-Mediated Late Endosome and Lysosome Morphology Defects Are Rescuable

(A) Representative LAMP1 staining (white) in fibroblasts transfected with TPC1 siRNA#1 and GFP-tagged siRNA-resistant TPC1 (green). Nuclei were stained using DAPI (blue). Zoomed images of cells that were negative (gray box) and positive (green box) for GFP are displayed in the right panels. Scale bars, 10 μm.

(B) Summary data quantifying LAMP1 intensity as a percentage of scrambled control (± SEM). Data are from 18–30 cells from two independent knockdowns.

(C) Representative CLEM of cultures similar to (A) with light microscopy images shown in the top panel (scale bar, 50 μm) from which a pair of cells (black blox; scale bar, 20 μm) were identified for EM. Bottom panels show cropped EM images of the cells in their entirety (center; scale bars, 2 μm) and zoomed images of the indicated region from the cell that was GFP-negative (left) and GFP-positive (right; scale bars, 1 μm).

(D) Summary data quantifying clustering of late endosomes/lysosomes expressed as a percentage of the area occupied relative to non-nuclear cytoplasm (± SEM). Data are from four cells under each condition.