Indeed imaging gastrulation in mouse embryos suggests that once cells have undergone EMT, Bra-expressing cells are pushed towards the streak in a process that appears to be passive and not require convergence and extension, as appears to be the case for frogs and fish [ 15].
Genes exhibiting high levels of promoter methylation during normal development remain suppressed in Dnmt1-deficient mouse embryos, suggesting that developmental gene control does not globally rely on cytosine methylation and that the effects of DNA methylation are limited to specialized processes such as imprinting and mobile elements repression [ 29].
Similarly, in vivo CD34 expression patterns in mouse and human embryos suggest that CD34+/c-Kitlow cells are located within the vascular walls including the dorsal aorta (Tavian et al, 1996; Wood et al, 1997).
In addition, cross protection experiments in mice, rabbits and chicken embryos suggest a high cross reactivity between the two viruses [55] [57].
In particular, increased recombination events at telomeres of mouse zygotes and two-cell embryos suggest that ALT is the driving force for the resetting of telomere length at early cleavage embryos (Schaetzlein et al, 2004; Liu et al, 2007).
Indeed, most of the 20S proteasome assembly is likely to be associated with the ZPAC Ump1 complex in early mouse embryos, as suggested from our data concerning the proteasomal activity (Fig. 3C).
Some studies using chick and mouse embryos have suggested that the surface ectoderm and its derivates (e.g. lens) play roles in optic-cup formation [ 10– 12], while others have indicated that the surface-ectoderm derivates, at least the lens, are not essential for NR invagination [ 13].
Gordon et al. [ 10] discovered increased expression of proangiogenic genes in the brains of mouse MEG3-null embryos, suggesting that deletion of MEG3 promotes angiogenesis.
These NMP-like cells were also shown to efficiently differentiate exclusively into paraxial mesoderm and posterior neurectoderm both in vitro and in vivo upon grafting into cultured mouse and chick embryos suggesting an NM bipotent character.
Ccdc80 is expressed in human mesenchymal stem cells and mouse embryo cartilage, suggesting a role in skeletogenesis [29].
