Fig. 4. Ncad k.i. embryos can attach and form blastocyst outgrowth. DIC images of wt (A) and Ecad^{Ncad-GFP/Ncad-GFP} (A') blastocyst outgrowths. Homozygous mutant embryos were able to attach and differentiate into trophoblast giant cells (arrow) and ICM (arrowhead). E-cad is expressed in the ICM and downregulated in giant cells of wt embryos (B) and is absent in the ICM of homozygous mutant embryos (B'). The trophoblast marker antibody TROMA-1 stained cells of both wt and mutant outgrowths (C-D'). D,D' are enlarged pictures of the outlined areas in C,C', respectively. Scale bar: 100 µm.