Sousa Lopes, S.C.D.

embryo pgc population stage 2null population cdx 2null embryos wnt 3a mouse cdx 2 streak cdx 2null mutants growth zone mutant growth development tissue somite mesoderm number extraembryonic mesoderm mouse embryo cdx 2null germ cells somite stages 3anull progenitors speci extraembryonic streak stage allantoic expression allantoi culture blimp 1 cdx genes bialecka expansion mutation fication blimp biology ohinata progenitor control deschamp van nes type embryos lawson hindgut endoderm allocation cdx 2 mutation wnt 3anull mutants pgc population expansion wnt 3anull embryos germ cell lineage explant 227–234 signi ficantly function maintenance pgc number allantoic growth lhf stage endoderm epiblast staining pgc allocation value takada formation increase niche activity level rescue cdx 2 probe allantoic bud stage patterning canonical wnt germ cell population