Figure 3.

F/M junction cells are multipotent stem cells of the gastric and stomach organs. (A) Schematic diagram of the cell lineage marking system. After shifting the flies with genotype UAS-FLP/+; wg-Gal4 UAS-GFP/actin5C-FRT-draf-FRT-tau-lacZ; tub-Gal80^ts/+ to 29°C, the Gal4 was activated and drove GFP (green) and FLP recombinase expression. The FLP recombinase then removed the ‘FLP-out’ cassette so that the constitutive actin5C promoter drove lacZ expression (red) permanently within all subsequent daughter cells. Flies with the genotype UAS-FLP/+; wg-Gal4 UAS-GFP/actin5C-FRT-draf-FRT-tau-lacZ; tub-Gal80^ts/+ (B–G) were cultured at the permissive temperature (18° C, B) and then shifted to the restricted temperature (29°C) for 8 hours (C), 1 day (D), 2 days (E), 4 days (F), and 7 days (G). The cardia was stained with anti-GFP (green), anti-β-gal (red), and DAPI (blue). Anterior is at the top in all panels. Scale bars: 50 βm (B, G); 20 βm (C–F).