Figure 2A-B. Representative 2D projection of confocal images showing the expression of the cell identity Castor in follicular cells control with Dronc expression (A: 109-30-Gal4 (BL7023)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/+) and without Dronc (B: 109-30-Gal4 (BL7023)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/ UAS-flippase (BL8209) DroncKO-FRT-Dronc-GFP-APEX-FRT-QF). Notice the reduction in the number of Castor-expressing cells in the FCD and the reduction in size of this region in B. Nuclei are labelled with DAPI (blue); Castor (green) and FasIII (grey) label the follicular cells; UAS-Histone-RFP labels the nuclei of Gal4-expressing cells (red). Data information: Scale bars represents 10 µm. Experimental flies were kept after eclosion from the pupae for 14 days at 29°C prior to dissection (applicable to all panels).C. Quantification of total number of follicular cells (left) and Castor-expressing cells (right) within the FCD (FasIII positive region) in either heterozygous or homozygous Dronc mutant conditions: Genotypes: CTRL= 109-30-Gal4 (BL7023)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/+; Dronc -/- = 109-30-Gal4 (BL7023)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/ UAS-flippase (BL8209) DroncKO-FRT-Dronc-GFP-APEX-FRT-QF.CTRL=ptc-Gal4 (BL2017)/+; UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/+. Dronc -/- = ptc-Gal4 (BL2017)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/ UAS-flippase (BL8209) DroncKO-FRT-Dronc-GFP-APEX-FRT-QF. N=2; the n number for each column in order of appearance n=16, n=14, n=20, n=17, n=19, n=18. Statistical significance was determined by using an unpaired parametric Welch's t-test (****p≤0.001). The median and quartiles are indicated in the violin plots. Data information: Experimental flies were kept after eclosion from the pupae for 14 days at 29°C prior to dissection (applicable to all panels).E. Percentage of germaria showing TUNEL staining in different cell types of the germarium (somatic cells and germline cells) upon altering Dronc expression in all of the escort cells and follicular stem cells. N=3 biological replicates; the n number of inspected germaria per condition is indicated close to the genotype. The genotypes in the graph are: White triangle (n=378 germaria) = ptc-Gal4 (BL2017)/+; +/+. Yellow circle (n=381) = ptc-Gal4 (BL2017)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/ +. Red square (n=196) = ptc-Gal4 (BL2017)/+; DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/ UAS-flippase (BL8209) DroncKO-FRT-Dronc-GFP-APEX-FRT-suntag-HA. Blue circle (n=184)= ptc-Gal4 (BL2017)/UAS-Dronc (BL56198); DroncKO UAS-Histone-RFP (BL56555) Tub-G80ts (BL7019)/+. An ordinary one-way ANOVA and Holm-Sidak's multiple comparison test was used to determine statistical significance (n.s = not significant; ** p≤0.01; *** p≤0.001; ****p≤0.0001). The graph shows the mean and standard deviations. Data information: Experimental flies were kept after eclosion from the pupae for 14 days at 29°C prior to dissection (applicable to all panels).J-K. Representative 2D projection of confocal images of the genotypes quantified in I. Nuclei are labelled with DAPI (blue). Red and green nuclei show the expression of different Fucci markers. FasIII (grey) was used to locate the FCD. Notice the reduction of follicular cells and limited overlap between the green and red fluorescent signals (white arrowheads) in K. Data information: Scale bars represents 10 µm. Experimental flies were kept after eclosion from the pupae for 14 days at 29°C prior to dissection (applicable to all panels).