Robo2 and Abl alter cell-cell adhesion to control CySC maintenance.(A–F) Confocal sections of testes with Zfh-1 staining CySCs and early cyst cell daughters (red). Positively marked mosaic clones are identified by presence of GFP (green). At 8 days ACI (A) control Abl4 CySCs (arrowheads) are present at high numbers in each testis, while (B) the number of Abl4 CySCs expressing ECad RNAi (arrowhead) remains low. At 10 days ACI, (C) marked Abl4 CySCs (arrowheads) are present in high numbers per testis, while (D) the number of Abl4 CySCs expressing β-cat RNAi (arrowhead) remains low. At 2 days ACI, (E) robo2  GSCs (asterisk), but not CySCs are present while (F) robo2  CySC expressing Abl RNAi (arrowhead) are present in the niche and produce cyst cell daughter cells (arrows). Hubs outlined in white, DNA stained with DAPI (blue), scale bars = 10 µm.