Fig. 1. Interference of ectopic Poxn with D-Pax2 functions in eye development. Left eyes of flies of the genotype indicated in each panel are shown in scanning electron micrographs. Note that the phenotype produced by ectopic Poxn expression under the control of the sev enhancer (A) is similar to that of spa^pol mutants (B), but stronger than that generated by ectopic Poxn expressed under the indirect control of the spa enhancer of D-Pax2 (G). Reducing D-Pax2 expression during eye development in heterozygous (C,H) or homozygous spa^pol (D) backgrounds enhances the phenotypes produced by ectopic Poxn, whereas raising D-Pax2 levels by an additional copy of D-Pax2 under the control of the sev (E) or spa (F) enhancer rescues the sev-Poxn phenotype to wild type (compare with Fig. 3D).