Fig. 1

Activated Toll signaling triggers cell death in wing development. Light micrographs of Drosophila adult wings (a–h) and fluorescence micrographs of third instar larval wing discs (a′–h′, a′′–h′′) are shown. Compared with the ptc-Gal4 controls (a–a′′), ptc > Toll^10B induces a loss-of-ACV phenotype in adult wings (b), massive cell death (b′) and apoptosis (b′′) in third instar wing discs, all of which are suppressed by expressing two independent dorsal RNAi (d–d′′, e–e′′) or Dronc^DN (f–f′′), but not GFP RNAi (c–c′′). Expression of Dorsal or depletion of cactus also results in the loss-of-ACV phenotype in adult wings (g, h), and increased apoptotic cell death in third instar wing discs (g′, g′′, h′, h′′). The lower panels show high magnification view of the boxed areas in upper panels (a–h). For all wings, anterior is to the left and distal up. i–k Statistical analysis of the ACV phenotype in adult wings (i, n = 50 for each genotype), AO positive cell number (j, n = 9) and cleaved caspase-3 (CC-3) activity (k, n = 10) in wing discs are shown. Error bar indicates standard deviation. One-way ANOVA test was used to compute P-values, ****P < 0.0001, ***P < 0.001, **P < 0.01. ptc>Dorsal flies were reared at 20 °C to avoid lethality at 25 °C, while ptc>cactus-IR were reared at 29 °C to enhance the expression of RNAi. See Additional file 1 for detailed genotypes. Scale bar: 100 μm