(A) Wing phenotypes induced by dpp>Trx are enhanced in Hira hemizygotes or dom heterozygotes. (B) Arista phenotypes induced by dpp>Trx are enhanced in Hira hemizygotes or dom heterozygotes. The percentages of arista-to-leg transformations are indicated in parentheses. Only thin leg-like tissues are induced by dpp>Trx alone, while authentic leg tissues are seen in Hira or dom mutants. (C) Ectopic Ubx expression induced by dpp>Trx in wing discs is enhanced in Hira or dom mutants. Top panel, Ubx staining in wing discs (red). Based on GFP signals, the same disc regions are boxed. Enlarged (2.1X) images of boxed regions are shown as inserts. Lower panel, merged images of DNA (blue), Ubx staining (red) with A/P boundaries marked by dpp>GFP signals (green). (D) Ectopic Antp expression induced by dpp>Trx in eye-antenna discs is enhanced in Hira or dom mutants. Top panel, Antp staining in discs (red). No signal is detectable in the WT sample. Lower panel, merged images of DNA staining (blue), Antp staining (red) and dpp>GFP signals (green). Antenna and eye discs are marked by A and E, respectively. The outline of the eye disc is marked by white dots. (A-D) Experiments were carried out at 21°C. (E, F) Occupancy of RNA polymerase II and tri-methylated histone H3 in Hox genes. ChIP analyses were carried out as described in Fig 1C for chromatin samples prepared from wing (E) or eye-antenna (F) discs of different genotypes.