Movie 5.

Apoptosis of the ICM cell in the chimaeric embryo at the early blastocyst stage. The same chimaeric embryo as in Movie 4 with ESCs visualised. Nuclei labelled with histone H2B-mCherry are visible in red. H2B-GFP ESCs introduced into the embryo are marked in green. The nucleus of the blastomere undergoing elimination is marked with a white circle.