Fig. 7. A tollo-Gal4 transgene drives lacZ expression (from UAS-lacZ) in the same cells that express Tollo mRNA. (A,C) lacZ activity visualized in tollo-Gal4; UAS-lacZ embryos. (B,D) Tollo mRNA detected in OreR embryos by in situ hybridization. In stage 12, germ band-extended embryos (A,B), lacZ activity (A) is detected in segmentally repeated bands of ectodermal cells that mirror Tollo mRNA (B). In the peripheral ectoderm at stage 13 (C,D) lacZ activity (C) is detected in domains of ectodermal cells. Segments T3 — A2 are shown in C,D, anterior towards the left and dorsal towards the top of the panel. Scale bar: 350 µm in A,B; 60 µm in C,D.