(A) Cartoons depicting inferred protein localization and hair orientation (brown) in wing cells of the indicated genotypes to explain rescue of pk by dachs, and rescue of fat by sple. Faint Sple and Ds indicate lower levels. (B) Schematic adult wing to show approximate location of panels shown in close-up, as indicate by letters. (C–N) Close-ups of portions of wings (as indicated in panel B) to show hair and bristle orientation in the indicated genotypes. Arrows indicate general direction of polarity. (C–F) Show wing margin bristles, (G–N) show wing hairs, in wild type (C,G), pk30 (D,H), dGC13/ d210 (E,I), dGC13 pk30 (F,J), UAS-RNAi-fat/+; C765-Gal4/UAS-dcr2 (K,M) and sple1 UAS-RNAi-fat/ sple1; C765-Gal4/UAS-dcr2 (L,N). Suppression of pk polarity phenotypes by dachs was 100% penetrant. For suppression of fat phenotypes by sple, near the proximal anterior wing margin (region K,L) in 10/10 fat RNAi wings scored hairs point predominantly towards the wing margin, whereas in 7/8 fat sple wings scored hairs point predominantly distally, and in 1/8 wings scored a substantial fraction of hairs (∼1/4) point towards the wing margin. Near the anterior cross-vein (region M-N), in 8/9 fat RNAi wings scored hairs point predominantly proximally, and in 1/9 wings scored hairs point predominantly towards the L3 vein, whereas in 5/8 fat sple wings scored hairs point distally, in 2/8 they point towards the L3 vein, and in 1/8 they point proximally.