Expression of CBF:H2B-Venus in mouse embryos at E6.5-E8.0. Expression of CBF:H2B-Venus in E6.5 embryos (A-B) showing strong expression in the anterior epiblast (ae, B, B1). Whole mount view of an E6.5 embryo (A). Transverse section through an E6.5 embryo (B). Expression of CBF:H2BVenus in E7.5 embryos (C-E). Lateral whole mount view of an E7.5 embryo (C). Transverse section through the anterior and posterior of an E7.5 (D, D1, E and E1) showing expression in the neural plate (D, D1) and in the primitive streak (ps) region in the epiblast (yellow arrowhead in E1), as well as in the nascent mesoderm (yellow arrow in E1). Expression of CBF:H2B-Venus in E8.0 embryos (F-H). Lateral whole mount view of an E8.0 embryo (F). Transverse section through the anterior and posterior section of an E8.0 showing expression in the headfolds (G and G1), cardiogenic plate (cp, red arrowhead, G1) in the mesodermal layer of the yolk sac (ys, H) and cells in the primitive streak region (yellow arrowheads, H2). All sections were counterstained with Hoechst to label nuclei. A, anterior; bl, blood islands; D, distal; emVE, embryonic visceral endoderm; m, mesoderm, P, posterior; Pr, proximal. Scale bars: 100 μm (D, E, G, G1 and H); 50 μm (B, E1 and H1); 30 μm (D1).