cactin-RNAi indirectly affects Rac activity in border cells. Related to Fig. 4. (A–D) Images of anti-aPKC staining egg chambers of c306-Gal4 together with (A and B) UAS-YFP-Rab5^S43N or (C and D) UAS-YFP-Rab11^S25N. (A and C) Images of border cell clusters. Yellow arrowheads indicate the apical junctions in the border cell clusters. (B and D) Images of posterior follicle cells. (A′–D′) Images show the single channel of anti-aPKC in A–D. (E–H) Images of anti-aPKC staining egg chambers of c306-Gal4 driven UAS-cactin-RNAi together with (E and F) UAS-YFP-Rab5^S43N or (G and H) UAS-YFP-Rab11^S25N. (E and G) Images of border cell clusters. (F and H) Images of posterior follicle cells. (E′–H′) Images show the single channel of anti-aPKC in E–H. (I and J) FRET images of border cell clusters of c306-Gal4 driven UAS-Rac-FRET together with (I) control (cross to w1118) or (J) UAS-cactin-RNAi. Scale bars, 20 μm. (K) Quantification of Front/Back FRET ratio in Control and cactin-RNAi. Each dot indicates a border cell cluster. (L) Quantification of the total FRET index in the border cell cluster. Each dot indicates a border cell cluster. (M) Quantification of delamination defects in stage 10 egg chambers.