Figure 4.

Regulation of Ommatidial Polarity by the Ft-Ds Pathway and Dachs

(A–F) Diagrams representing the chirality and orientation of ommatidia in the adult eye. Dorsal chiral form of ommatida (red), ventral chiral form (green), achiral ommatidia (blue), and disrupted ommatidia (^∗) marked. Eyes wholly mutant for specific genotypes were generated using the eyeless-GAL4 UAS-FLP (“EGUF”) system except in (E).

(A) FRT40.

(B) ft^G-rv FRT40.

(C) dachs^GC13 FRT40.

(D) ft^G-rv dachs^GC13FRT40.

(E) ft^G-rv dachs^GC13 UAS-wts / ft⁸ dachs¹ tub-GAL4.

(F) ft^G-rv dachs^GC13 FRT40 UAS-yki.

(G) Quantification of polarity defects. Columns 1–6 are the same genotypes as in (A)–(F). Additional genotypes are ds^UA071 /ds^38k (column 7) and ds^UA071 d^GC13 / ds^38k d¹ (column 8).

Error bars show SEM between eyes (n > 6). A one-way ANOVA test was applied (^∗∗∗p < 0.001, ^∗∗p < 0.01, ^∗p < 0.05 comparisons between columns linked by bars). ft^G-rv/ ft⁸ eyes could not be examined for comparison with genotype in (E) because the combination is lethal. However, ft⁸ EGUF eyes have a level of inversions (data not shown) similar to ft^G-rv eyes, suggesting that the polarity phenotype is suppressed in (E).

(H–J) Diagrams representing orientation of ommatidia around overexpression clones (yellow).

(H) Act≫GAL4/UAS-ft.

(I) Act≫GAL4/UAS-ds.

(J) dachs^GC13/dachs¹ Act≫GAL4 UAS-ds.

Equator is toward the bottom and pole toward the top of the images. Nonautonomous inversions in polarity occur on the equatorial side of UAS-ft clones (H) and on the polar side of UAS-ds clones (I). UAS-ds clones in a dachs mutant (J) produce polar inversions at the same level with an average of number of inversions per clone in WT of 2.8 (n = 4) and 2.7 in dachs (n = 7).

See also Figure S4.