(A–D) Cuticle preparations of male adult wings expressing the indicated RNAi hairpins under the control of nub-gal4 and grown at the indicated temperatures. In B-D, flies carry the tub-gal80ts transgene. High magnification of rudimentary wings are shown in A and D, and percentages of wing size with respect to control GFP-RNAi expressing wings are indicated in A, C, and D. Wing blade (wb, pink) and hinge structures (alula and costa, blue) are shaded in A. Scale bars in A-D, 300 µm. Scale bars in the squared wings in A, D, 150 µm. (A’–D’) Histograms plotting tissue size of the wing blade with the indicated genotypes normalized as a percent of the control wings. Error bars show standard deviation. Number of wings per genotype and temperature >15. ns, not significant; ***p<0.001, *p<0.05. (E–I) Late third instar wing discs of the indicated genotypes, grown at 29°C, and stained for Wg and Ptc (E, green), DAPI (E, blue), Nub (E, red), dpp mRNA (purple, F), p-MAD (G, red), Spalt (H, red), Omb (I, red) and Brk (G-I, green). Scale bars, 50 µm (E–I) or 25 µm (higher magnifications in E, F). Higher magnifications of the dorsal hinge region are shown below each wing disc in panel E. In E, inner (IR) and outer (OR) rings of Wg, and dorsal (D), ventral (V), anterior (A) and posterior (P) compartments are marked. Note that the width of the hinge is largely unaffected by Dpp depletion. In F, dpp mRNA levels are reduced in the wing pouch (wp) when compared to the hinge region (black arrows). Higher magnifications of the wing pouch are shown below each wing disc in panel F.