Figure 3.

Epithelial Wg is dispensable for homeostatic self-renewal. (A–L) esg^ts>F/O (esg-gal4, UAS-FLP, actin5C>stop>gal4, UAS-GFP, tub-gal80^ts) clones from guts with the indicated genotypes after 2, 14 and 28 days of incubation at 29°C to induce clones. There was no change in esg-derived clones in homeostatic conditions upon loss of wg or wls (compare A–C with D–F, G–I, J–L). (M) Quantification of Delta^+ve cells in posterior midguts of the indicated genotypes. Note that Delta^+ve ISCs numbers were not decreased by knockdown of wg or wls or by heterozygosity for the null allele wg^CX4. However, these conditions prevented the mild increase in ISCs observed in aged guts (M; ***P<0.0001, **P<0.005 Student’s t-test). (N–Q) esg^ts>F/O midguts from the indicated genotypes after 14 days of clone induction and treated with Pe (compare with B, E, H, K, respectively). Note the requirement of epithelial-derived wg and wls for damage-induced proliferation. (R) Quantification of pH3^+ve cells in posterior midguts of the indicated genotypes and treatments. Note the suppression of damage-induced proliferation when wg or wls is knocked down (***P<0.0001 one-way ANOVA with Bonferroni’s multiple comparison test). Scale bars: 60 μm.