Figure 4.

The initiator caspase Dronc and its adaptor Dark are required for PC apoptosis. Confocal images of stage 7–10 hsp-flp/+; +/+; FRT42D dronc^i24/i29/FRT42D P[ubi-GFP] (a–c) and hsp-flp/+; +/+; FRT42D dark^G8/FRT42D P[ubi-GFP] (d–f) ovarian follicles stained with Fas3 antibodies (red) to label PC membranes and GFP antibodies (green) to identify homozygous dronc and dark mutant clones (absence of green staining). The apical side of the follicular epithelium in which the PCs are embedded is toward the top. White arrowheads and yellow arrows mark PCs destined to survive or die, respectively, as indicated by the round shape, smaller size and more basal position, indicating progressive exclusion of the latter from the group. The presence of PC groups with more than two cells (three or four) is always associated with the presence of at least one or two dronc or dark homozygous mutant PCs