Figure 5

Notch acts in escort cells to expand the cap cell niche. (A) Expression patterns of Gal4 lines used. (B) C587-Gal4 and Ptc-Gal4 driven expression of NICD in adult niches controlled by Gal80^ts leads to increasing numbers of cap cells compared to WT at day 15 (respectively P < 0.05, and P < 0.001, t-test) while Bab1-Gal4, En-Gal4 or C306-Gal4 driven NICD expression has no effect. (C) Example of expanded cap cell niche (arrow) resulting from expression of NICD with C587, stained with anti-Coracle (purple), anti-LaminC (green). (D) Cap cells do not undergo mitosis. BrdU labelled ovariole after 15 days of expression of NICD with C587 Gal4. Cap cells (arrow), marked with anti-Coracle (purple) are not labelled with BrdU (green). Dapi is marked grey. In contrast, proliferating germ line and follicle cells did incorporate BrdU (n = 225). (E) C587 driven NICD expands niche similarly in flies maintained on St + Yeast and P/G-depleted media. Data in B, E shown as mean ± SEM. Data in B are normalized to % of cap cells on eclosion. (B) n = 43–61; (E) n = 59–62.