A Esg knockdown in ISC/EBs causes reduced Notch reporter activity in EBs. Use of a Notch (N) activity reporter (
Su(H)-
lacZ; Bray & Furriols,
2001) reveals a noticeable reduction in N signaling within EBs, despite of seemingly unaltered Delta expression in ISCs. Midguts of the indicated genotypes were stained with DAPI (all nuclei), Delta (ISCs) and β-GAL (EBs) following 4 days of incubation in 10 μg RU486/ml or ethanol-containing food as indicated.