Fig. 3. Ectopic eye induction mediated by ey is inhibited by Antp. Reciprocally, Antp-induced phenotype is inhibited by ey. EY, ANTP and both are expressed using the UAS/GAL4 system with dppblink-Gal4 as driver. (A) Ectopic eyes induced by ey. (B) Antenna-to-leg transformation and eye development inhibition induced by Antp. (C) Lack of ectopic eyes and antenna-to-leg transformation when both proteins are co-expressed. (D) ANTP HD-deleted protein is unable to repress ectopic eye formation. (E–G) EY and ANTP co-localize in the discs, resulting in the inhibition of ectopic eye development. Immunostaining experiments using EY (green) and ANTP (red) antibodies, analyzed by confocal microscopy. Only the merge is presented. (E) Wing disc; (F) leg disc; (G) eye–antenna disc (eye disc at the bottom). (H and I) ANTP-EY co-expression blocks neuronal differentiation and (J and K) so induction. (H) UAS-ey crossed with dppblink-Gal4. Wing disc stained with an EY antibody (green) and the 22C10 neuronal marker (red). (I) Same staining as in (H) but here EY and ANTP are co-expressed. (J and K) β-galactosidase expression of the so enhancer trap line following expression of EY (J) or EY and ANTP (K) in the wing disc. so is not expressed in the wild-type wing disc (not shown). (L–O) Effect on eye development of ANTP-deleted or mutated proteins. Crosses of the UAS constructs indicated in the figure were performed using the driver EYE-GAL4. (L) Wild-type eye; (M) UAS-AntpΔHD construct, HD is deleted; (N) UAS-AntpK50, the Antp DNA-binding specificity is changed to that of Bicoid; (O) UAS-AntpA50,51. Residues involved in DNA contacts have been mutated in order to abolish binding to DNA.