Fig. 6. Ecdysone-dependent transformation of ph mutant neurons in cultured mosaic larval brains. Composite confocal images of variably cultured larval brains that contain clones of ph mutant neurons with GAL4-OK107 as a driver. Few GFP-positive cells exist after 4 days of culture in the absence of 20-hydroxyecdysone (A). By contrast, there are many GFP-positive cells when ecdysone was added at the beginning (B) or on the fifth day of the culture (C). Genotype: FRT19A/FRT19A,hs-FLP,tubP-GAL80;UAS-mCD8-GFP/+;GAL4-OK107/+. Scale bar: 20 µm.