Fig. 4. Dgo, with Pk and Stbm, promotes the apical localization of Fmi and Fz. Apical confocal sections are shown; anterior is leftwards and the equator at bottom. MF is at left margin of panels, except in F where it is indicated by red arrowhead. Mutant tissue is marked by absence of ß-gal staining or GFP (blue). White/yellow arrows indicate PCP protein localization in R3/R4 pair (row 3 or 4) and arrowheads indicate the R4-like enrichment (row 5 and posterior), except in F where it indicates clones ahead of MF. Fmi (green) and Fz-GFP (red) localization is analyzed in mutant tissue of null alleles of the respective PCP genes. (A) pk^–: no significant abnormalities in the apical localization of Fmi. (B) pk^–, dgo^–: loss of apical Fmi localization. (C) pk^–, dgo^–: reduction in apical Fz localization. (D) dgo^–, stbm^–: loss of apical Fmi localization (compare with A and B). (E) dgo^–, stbm^–: loss of apical Fz-GFP localization. The vertical arrow indicates a mosaic in which the R3 specific Fz-GFP staining is missing. (F) pk^–, stbm^– mutant clones behind and ahead of MF (marked by red arrowhead): apical Fmi localization is lost in mutant tissue ahead of MF, similar to pk^–, dgo^– and pk^–, stbm^– double mutants (compare with B and C), but apical localization of Fmi is observed posterior to MF, although no clear pattern is detected. In pk^–, stbm^– double mutant tissue there is a different effect on Fmi anterior and posterior to MF. (F) pk^–, stbm^–: apical Fz-GFP localization behaves like Fmi: it is unaffected posterior to MF (but lost anterior to MF, not shown).