Figure 7

Mild defective positioning phenotype in embryoid bodies and compensatory expression of Arh and Numb in Dab2 null ES cells and embryos. (A) In some of the dab2 (-/-) ES clones (such as clone dfg15), a monolayer epithelial structure is seen at some of the surface of embryoid bodies (indicated by arrows), as shown by an example of a section stained with Dab2 (green) (no signal in this image), GATA4 (red), and DAPI (blue). (B) Western blot shows that Arh and Numb were variably expressed in embryoid bodies derived from several ES cell clones of different dab2 genotypes. (C) The expression of Dab2, Arh, and Numb adaptors proteins was analyzed by Western blotting of E9.5 embryos from matings between female dab2 (fl/fl) and male dab2 (+/df); Sox2-Cre. The embryos were harvested, dissected free of extraembryonic tissues, lysed and denatured in SDS buffer, and probed for Dab2, Arh, and Numb. The extraembryonic tissues were used for genotyping.