Fig. 5. Development of bubR1^Rev1 embryos following spindle damage. Wild-type and bubR1^Rev1 embryos at 0-3 hours AEL were incubated with colchicine during 30 minutes, fixed and immunostained with anti Phospho-Histone H3 antibodies. Merged images show DNA (blue), anti-PH3 (green) and BubR1 (red). Following colchicine treatment, (A,A'') Wild-type nuclei arrest in a prometaphase-like stage and are Phospho-Histone H3 positive, while a significant proportion of bubR1^Rev1 embryos are Phospho-Histone H3 negative (B,B''). Following colchicine treatment, BubR1 accumulates at kinetochores of (C) wild-type prometaphase-like nuclei but is not detectable in (D) nuclei from bubR1^Rev1 embryos. (E) Quantification of Phospho-Histone H3-positive embryos treated with colchicine during cycle 3-6, 7-9 and 10-13 (wild-type embryos: n=32 for cycle 3-6, n=21 for cycle 7-9 and n=37 for cycle 10-13. bubR1^Rev1 embryos: n=54 for cycle 3-6, n=18 for cycle 7-9 and n=47 for cycle 10-13. We considered embryos positive when more than 80% of nuclei were Phospho-Histone H3 positive. Scale bar: 10 µm.