dUBPY regulates endocytic DFz2 trafficking in the wing disc. (A–E″) Control (A–A″, D–D″), dUBPY-overexpressing (B–B″), and dUBPY RNAi (C–C″, E–E″) wing discs expressing DFz2-FLAG (A–C″) or not (D–E″) were stained with anti-FLAG (A–C) or FK2 (D, E) antibody together with anti-Rab7 (A′–E′). Closed and open arrowheads indicate Rab7-positive and Rab7-negative endosomes, respectively (A–C″). Insets in C–C″ and E–E″ show high-magnification images of typical Rab7-positive endosomes. (F–F″) FK2 staining (F) of a dUBPY knockout clone in the wing disc, which is negative for β-gal (F′, −/−). A″–F″ are merged images. (G) Control and dUBPY-overexpressing wing discs expressing DFz2-FLAG were double-stained with anti-FLAG and anti-Rab7 antibodies as in A–A″ and B–B″. Percentage of FLAG/Rab7-double-positive endosomes among total FLAG-positive endosomes was then determined (mean±s.d., n [field of view]=5–7, *P<0.01, t-test). (H–I′) Anti-FLAG (H, H′) and FK2 (I, I′) staining of DFz2-FLAG wing discs co-expressing Rab11S25N in the wing pouch. H′ and I′ show high-magnification images of the wing pouch regions in H and I. Bars, 10 μm. (J) A model for the regulation of the cell surface level of Fz.