Fig. 5. Inductive effect of HhN but not of Hh from peripodial cells upon disc proper cells. (A-C') Expression of Hh-GFP (A,a,A',a'), HhN-GFP (B,b,B',b') and Hhc85s-GFP (C,c,C',c') in peripodial cells using the Ubx-Gal4 driver. The Ubx is expressed at high levels in the part of the peripodial membrane corresponding to the P compartment (arrowheads in A,B,C). HhN-GFP and Hhc85s-GFP, but not wild-type Hh-GFP, are observed in internalized vesicles in the cells of the disc proper (arrows in posterior and arrowheads in anterior compartment in A',B',C'). The internalized vesicles of HhN-GFP are more clearly visualized in the A than in the P compartment, unlike Hhc85s-GFP vesicles, which are visible in both A and P compartments. Dpp (red) is ectopically induced in the disc proper cells in HhN-GFP/Ubx-Gal4 disc (B,B'). (D-G) Wing and notum phenotypes of the Hh-GFP/Ubx-Gal4 and Hhc85s-GFP/Ubx-Gal4 (D,F), HhN-GFP/Ubx-Gal4 flies (E,G). The notum is enlarged and contains extra-macrochaetae (G) and there is modification of the wing pattern (E) in HhN-GFP/Ubx-Gal4 flies. (H) Diagrams showing the organization of the disc proper cells and peripodial cells in a front- and transverse view of a wing imaginal disc.