Crb overexpression in PCs leads to an expansion of the apical membrane domain.

(A) Schematic representation of the large intestine with the dorsal domain (dd) in orange, the ventral domain (vd) in blue and the BCs in green. (B–B″) Confocal microscope images of a stage 15 embryonic hindgut expressing UAS-crb^full under the control of en-GAL4 in the PCs of the dorsal domain. The hindgut is stained with anti-Crb (magenta), anti-DPar6 (grey) and anti-Dlg (green). The insets show higher magnifications of the vd (outlined by the grey dotted line), which serves as control tissue and the dd (outlined by the blue dotted line) where the altered apico-basal polarity in cells overexpressing Crb is highlighted (due to the very strong overexpression of Crb in the dd, the gain of the microscope was strongly reduced).