Figure 3.

Ectopic expression of PipB2 induces the redistribution of LE/Lys, but not other organelles, to the extreme cell periphery. HeLa cells were transiently transfected with pGFP-PipB2 and processed for immunofluorescence 24 h later using antibodies against LAMP-1 (LE/Lys glycoprotein) (A), cathepsin D (lysosomal enzyme) (B), LBPA (late-endosome specific lipid) (C), EEA-1 (early endosomes) (D), and TGN46 (trans-Golgi network marker) (E). Samples were viewed by confocal microscopy. An overlay of the two channels is presented on the right (GFP-PipB2, green; and organelle marker, red). Insets show 2× enlargement of boxed area. Asterisks indicate transfected cells and arrowheads indicate peripheral accumulation of GFP-PipB2 and/or LE/Lys. Bar, 20 μm.