Abi genetically and physically interacts with Dlar. (A and B) Confocal images from the basal surface of dlar5.5 (FRT40A) mosaic egg chambers (stage 7). (A) A small dlar mutant clone (positively marked by the presence of the CD8-GFP marker, blue) shows no changes of the actin cytoskeleton (F-actin, white), whereas (B) within a large dlar mutant clone, the basal actin-rich protrusions are strongly reduced. (C) Quantification of the frequency of round eggs of dlar^5.5/dlar^13.2 (n = 314) and dlar^5.5/dlar^13.2;abi/+ (n = 257) compared with wild type (n = 265). ***, χ² < 0.001 (χ² test). (D) GST pull-down with GST–Dlar-D2 or GST coupled to glutathione beads incubated with extracts of S2 cells transfected with Abi. (E and F) Proposed model of how Fat2 acts through the WRC to drive collective cell migration during global egg rotation.