Fig. 3. Effects of ectopic D-mib and D-mibRF on Notch-regulated developmental patterning. (A) Wild-type adult head. (B) sca-Gal4>UAS-D-mib head is missing several macrochaetae. (C) sca-Gal4>UAS-D-mibRF exhibits macrochaetae tufting. (D) Wild-type wing. WM, wing margin; asterisk marks a wing vein. (E) bx-Gal4/Y; UAS-D-mib wing displays longitudinal vein breaks (asterisk) and lacks crossveins. (F) bx-Gal4/Y; UAS-D-mibRF is vestigial and completely lacks a wing margin; the remaining wing tissue present is composed mostly of severely thickened wing veins (asterisk). (G) Close-up of the L3 vein in a dpp-Gal4/+ wing; arrowheads point to two campaniform sensilla. The normal thickness of vein is denoted with a bracket. (H) dpp-Gal4, UAS-D-mib wing lacks campaniform sensilla. (I) dpp-Gal4, UAS-D-mibRF wing displays an extremely thickened L3 vein and a vast surplus of campaniform sensilla; both features are indicative of failed Notch signaling. (J-L) Third instar wing imaginal discs stained for Sens; only the wing pouch region is shown. (J) In wild type, sensory organ precursors for L3 sensilla are indicated (arrow). (K) sca-Gal4>UAS-D-mib lacks some L3 sensory precursors. (L) sca-Gal4>UAS-D-mibRF shows ectopic L3 sensory precursors. As the sensory multiplication defect is more prominent at later times, the disc in panel L is slightly older than those of panels J and K. (M) Cut expression at the prospective wing margin (WM) in wild type. (N) dpp-Gal4, UAS-D-mib shows normal wing margin development. (O) dpp-Gal4, UAS-D-mibRF disc shows a gap in the wing margin in D-mibRF-expressing cells (asterisk).