Fig. S3

ctcf morphants do not exhibit increased apoptosis. Staining with acridine orange labels apoptotic cells and was performed on rad21^nz171 mutants, ctcf morphants, and wild type controls at 24 h.p.f. ctcf morphants were obtained by injecting wild type embryos at the 1-4 cell stage with 0.75pM CTCF splx2 morpholino (ctcfMO: 5′CCAAAACAGATCACAAACCTGAAAG3′). Embryos were dechorionated and incubated in 5 μM acridine orange solution for 30 minutes. After rinsing in embryo medium, embryos were imaged with an Olympus IX71 microscope and DP Controller software. A. rad21^nz171 mutants exhibit high levels of apoptosis as indicated by the presence of large numbers of acridine orange-positive cells. B, In contrast, ctcf morphants exhibit equivalent numbers of acridine orange-positive cells to the wild type embryos shown in C. Groups of 24 h.p.f. embryos are shown, and these are are representative of three independent experiments.