Fig. 2. RLVs are MVBs. (A) Immunoelectron microscopy localizes Rh1 to MVBs in 87% pd photoreceptors. (B) Confocal projections of ommatidia isolated from newly eclosed Rh1-Gal4, UAS-Rab7-GFP flies. Rab7-GFP outlines RLVs, whereas Rh1 stains more uniformly. Arrows indicate corresponding RLVs. RLVs, ER and Golgi (not shown) are distributed evenly throughout photoreceptors, unlike cell types in which pericentriolar cytoplasm is a focus for endosomal organization. (C) Hrs localizes to RLVs in 78% pd ommatidia. Arrows indicate corresponding RLVs. Scale bar: 500 nm in A; 4 µm in B; 2 µm in C.