K-M. Representative images of midgut sections from the R4 region of Drosophila carrying esgts-GAL4-driven expression of lacZ cDNA (K, control), Las RNAi (L), or Las RNAi and dominant negative form of EGFR (EGFR-DN, M). GFP (green) and Dl staining (red) was used to visualize ISCs. Data information: DAPI stained nuclei are shown in blue. Scale bars represent 10 μm 