Figure 4

Figure 4 (A) Representative confocal images of immunofluorescent staining for phosphorylated Smad2 and DAPI-labeled nuclei in 8hpf explants from WT embryos injected with 10 pg ndr2. DAPI z-stacks were used to create a three-dimensional mask from which nuclear pSmad intensities were detected and measured in an automated fashion. (B, C) Axis position of pSmad2-positive nuclei (blue) and all nuclei (gray) in explants from WT embryos injected with 10 pg ndr2 (B) or uninjected (C) at the time points indicated. Each dot represents a single nucleus, pink bars are median values among pSmad2+ nuclei. N indicates the number of explants in each condition from five independent trials. Kolmogorov-Smirnov tests were used to compare the distribution of pSmad+ nuclei to all nuclei; ****, p<0.0001; **, p<0.01. (D) Representative images of WISH for lefty1 in uninjected (top) and ndr2-injected (bottom) explants fixed at the time points indicated. Scale bars are 100 μm