Figure 1.
Effect of His2Av mutations on Pc-mediated silencing. (A–D) Expression of homeotic proteins in wild-type and mutant larvae. Brains and ventral ganglia were dissected from OR and His2Av810 third instar larvae and stained with antibodies against Antp and Ubx. (A) Distribution of Antp in the central nervous system of OR larvae. (B) Distribution of Antp in the central nervous system of His2Av810 larvae; arrows point to sites of ectopic expression. (C) Distribution of Ubx in the central nervous system of OR larvae. (D) Distribution of Ubx in the central nervous system of His2Av810 larvae. (E–P) Effect of His2Av mutations on Pc and E(z) localization. Polytene chromosomes from third instar larvae were dissected from OR and His2Av810 mutant larvae and stained with rabbit polyclonal anti-Pc and anti-E(z), and rat polyclonal anti-Su(Hw) antibodies. The bound antibodies were detected using FITC-labeled goat anti-rabbit (green) and Texas red-labeled goat anti-rat (red) secondary antibodies. (E,H,K,N) DNA stained with DAPI. (G,J,M,P) Chromosomes stained with Su(Hw) as a control. (F) Distribution of Pc in chromosomes from the wild-type strain OR. (I) Pc in chromosomes from His2Av810 mutant larvae. (L) E(z) in wild-type OR. (O) E(z) in His2Av810 mutant larvae.