Figure 7

Ommatidial patterning and wing hair alignment are abnormal in vari mutants. (A-C) Ubiquitous overexpression of Vari using daughterlessGAL4 in heterozygous vari^48EP(A), homozygous vari^48EP(B) and WT backgrounds (C). (A'-C') Magnified images of A-C. Overexpression of Vari in a WT background results in mild phenotypes such as missing interommatidial bristles (IOBs) (arrowheads) or irregularly patterned bristles (below the asterisk). Overexpression of Vari in a null mutant background results in missing ommatidia and extra IOBs (arrows, B'). (D-F) When the FLP/FRT mosaic approach is used to generate patches of vari^48EPnull tissue in the developing eye disc, mutant cells are not seen in the adult eye, although fused ommatidia (arrowhead, D), missing bristles (arrow, D) and duplicated bristles (arrowhead, E) are seen. Heat-shocked siblings, in which all cells are WT for vari, are normal (F). (G-J) No phenotypic effects are observed in the wing by overexpression of Vari in a WT background. Wing hairs retain a parallel alignment while pointing distally (H). In a null mutant background, imposed expression of Vari results in abnormal wing hair alignment (arrowhead, G). While some hairs point distally, patches of hairs point in random directions with irregular alignments when compared with neighbouring hairs. If Vari levels are reduced in developing wing tissue, as in UAS-variIR; dpp-GAL4, flies, patches of wing hairs with mis-aligned hairs, and un-extended hairs (arrowhead) are seen. Wings mosaic for vari also have patches of un-extended hairs (arrowhead, J). Overall morphology of all wings is similar to the WT (insets). (K) Mosaic patches on the dorsal thorax reveals patches of naked cuticle, and duplicated bristles (arrowhead). WT, wildtype. Magnification: A-C: 140×; A'-C, F': 300×; D, E: 450×; G-J: 20×; K: 50×.