Fig. 3. Analysis of PGC migration in Cx431KO mouse embryos. (A,B) An example of how GFP-expressing PGCs were visualized and tracked in an E8.5 mouse embryo by time-lapse imaging. The migratory paths of individual PGCs are superimposed on the image of the embryo seen at the beginning of the experiment (A), and for clarity are plotted with a single origin in B. (C,D) The migratory paths of PGCs in E8.5 and E11.5 embryos were used to determine the speed (C) and directionality (D) of cell locomotion. PGCs from both homozygous and heterozygous Cx431KO embryos demonstrated significant decreases in both speed and directionality. This data entailed the analysis of a total of 72 Cx431 +/+, 74 Cx431 +/- and 66 Cx431 -/- independent cell migration tracings obtained from five embryo explants for each of the three Cx431 genotypes. Scale bar: 100 µm.