FIG. 2.

Arrested development and gastrulation failure in presumptive Ezh2-deficient embryos. Deciduae at day 7.0 to day 7.5 were isolated, sectioned at 5-μm thickness, stained with hematoxylin-eosin, and scored for being normal or abnormal based on size and morphology. (A) An almost-sagittal section through a wild-type embryo at day 7.5. (B to D) Sections of presumptive Ezh2 mutants isolated at days 7.0 to 7.5. The arrow in panel C highlights excessive amounts of mesoderm aberrantly accumulating onto the abnormal embryo. The different magnifications of each photograph are indicated. Abbreviations: A, anterior; Al, allantois; Am, amnion; E, embryonic; EE, embryonic ectoderm; Ec, ectoplacental cone; Ex, extraembryonic; ExE, extraembryonic ectoderm; P, posterior; Ch, chorion; VE, visceral endoderm.