Extended Data Figure 3. Activity of the wingless promoter during imaginal disc development.
a, Timing of key developmental stages at 25°C. b, Developmental timing at 18°C as it relates to the results illustrated in (c). c, Permanent labelling of wingless-expressing cells and their descendants at different stages of development. Genotype was wg[KO; Gal4], tubulin-Gal80ts/UAS-Flp; Actin-FRT.stop.FRT-Lac-Z so that the stop cassette was only excised in cells that express wingless at the time of shifting to 29°C to activate Flp expression and hence excision of the stop cassette. Discs were shifted from 18°C to 29°C at different stages (shown in b) but they were fixed and stained at the same stage, just before puparation.