Fig. 4. Chromatin decondensation and nuclear re-organisation of Hoxb1 in rhombomere 4. (A) The distribution of squared interphase distances (d²) in µm² measured between probes for Hoxb1 and Hoxb9, in rhombomeres 1 and 2 (r1/r2), r4 and r5 from E9.5 embryos. (B) Histogram showing the position (µm) of Hoxb1 hybridisation signals, relative to the inside, edge or outside of the MMU11 territory, in nuclei from r1/r2 (black bars), r4 (white bars) and r5 (grey bars) of two E9.5 embryos from different litters. Negative distances indicate signals localised beyond the visible limits of the detectable CT (n60). (C) Histogram showing the position of Hoxb9 hybridisation signals, relative to the MMU11 territory edge, in nuclei from r4 (white bars) and r5 (grey bars) of two E9.5 embryos from different litters. Negative distances indicate signals localised beyond the visible limits of the detectable CT (n60).