Fig. 6. Localization of Fas2, Dlg and Lgl in mutant, misexpression and rescue clusters. The delamination and migration times are shown in Fig. 4. Polarity values are ratios of Fas2 at the leading half of PC to Fas2 at the trailing half of PC, and are mean±s.d. from on average 10 measurements. (A-A'') Fas2 colocalizes with Dlg and Lgl at the leading half of the PCs. Dlg and Lgl colocalize in the cortex of BCs. (B-B'') In Fas2^rd1 clusters, Dlg and Lgl are mislocalized in BCs. In PCs, Fas2 remains polarized, and Dlg and Lgl colocalize in a similar pattern (arrowheads). (C-C'') Complete loss of Fas2 in Fas2^null PCs causes Dlg and Lgl fragmentation and loss of polarity (arrowheads). As in Fas2^rd1 clusters, Dlg and Lgl are mislocalized in BCs. Fas2 is polarized in dlg^hf/+ and lgl⁴/+ clusters that contain functional Dlg or Lgl reduced by half (D,F). Further reduction of Dlg in dlg^hf/dlg^lv55 clusters (E'), and Lgl in lgl⁴/lgl^ts3 clusters (G'') results in the loss of Fas2 polarity (E,G). (H-H'') Fas2, Dlg and Lgl colocalize in a circumferential pattern in PCs in UAS-Fas2/+; BA3-Gal4/+ clusters. Fas2, Dlg and Lgl colocalize in polarized pattern in PCs in UAS-Fas23/+; BA3-Gal4/+ clusters (I-I''), and in UAS CD8-Fas2/+; BA3 Gal4/+ clusters (J-J''). (K) Fas2 polarity in Fas2^rd1 PCs is restored when Fas2 is targeted to PCs. (L) Polarity of Fas2^rd1 PCs is abolished when Dlg is targeted to BCs. In all cases, decrease of Fas2 polarity correlates with the delay of BC delamination. Arrowheads indicate the accumulation of Fas2, Dlg or Lgl.