Figure 3.

Notch signaling defect in adult wings and larval wing discs. Compared to yw flies, representing wild-type (A), wings from flies of the genotype en2.4-Gal4^e22c, UAS-flp/+; FRT^82B/FRT^82B, awd^j2A4 (B-C) show typical Notch phenotypes: enlarged wing veins (arrows) and loss of wing margins (‘notched’ wing blades). (D) Drawing of a third instar wing disc in apical view showing the dorsal-ventral (D, V) compartment border (red line) specified by the Notch activity. The wing disc pouch is the central fold of the disc (green) and will generate the wing blade. The black box approximately indicates the areas shown in E and F. (E) The discs were dissected from hs-flp; +/+; FRT^82B, Ubi-GFP/FRT^82B, awd^j2A4 third instar larvae. wingless (wg) is a downstream activation target of notch. Wg protein expression is lost in the awd clone (loss of GFP; empty block arrow) overlapping the midline (dorsal-ventral boundary, where Notch specifies wg expression). (F) The discs were dissected from hs-flp/GbeSu(H)_m8-lacZ; act-Gal4, UAS-GFP/+; FRT^82B, act-Gal80/FRT^82B, awd^j2A4 third instar larvae. GbeSu(H)_m8-lacZ expression (red) is also lost in awd MARCM clones (expressing GFP; empty block arrow). Bars are 10 μm.