|
Fig. 7. Combinatorial effects of Nodal/Activin and Klf4 on germ-layer differentiation. (A) The effect of blocking Nodal/Activin via injection of dnXAR1 or treatment with SB431542 (SB) on Klf4-induced endoderm gene expression. The ‘ctrl’ and ‘dnXAR1’ embryos were orientated in vegetal view; the others were in lateral view to show staining in both vegetal and animal regions. (B) Quantification of embryos with normal or altered Sox17α expression in A in triplicate. (C) The effect of K4MO or/and Xnr2 mRNA injection on mesoderm and endoderm gene expression. The embryos are in lateral view. (D) Quantification of embryos with normal or altered gene expression in C in triplicate. (E) The effect of injection of dnXAR1 or/and K4MO on mesendoderm gene expression. The embryos for ‘Xbra’ staining are in lateral view, whereas the rest are in vegetal view. (F) Quantification of embryos with normal or altered gene expression in E in three experiments. In all experiments above, 1.5 ng dnXAR1 mRNA, 300 pg Klf4 mRNA, 15 ng ctrlMO or K4MO, 2 pg Xnr2 mRNA were injected. Injected or treated embryos were collected at stage 10.5 for whole-mount in situ hybridization. |