Fig. 7. Ultrastructural changes in lysosomes and late endosomes in SKD1(E235Q)-expressing cells. 3Y1-B cells were infected with an adenovirus encoding GFP-SKD1(E235Q) and processed for immuno-electron microscopic analysis with the antibody against LGP107 followed by protein-A conjugated to 15 nm gold particles. In control cells (A,B), gold-labeled lysosomes and MVBs (late endosomes) are indicated by arrows and arrowheads, respectively. Adenovirus-infected cells (C-F) showed an accumulation and enlargement of hybrid organelles. The clusters of MVBs are indicated by arrows (C,E,F) and the enlarged hybrid organelle containing indigestive materials are marked by asterisks (C,D), respectively. The typical hybrid organelle-like structures (MVBs directly fused with electron dense lysosomes) are indicated by arrowheads (A,C,E). Bars, 1 µm.