Fig. 5. GATAa activity is blocked in the vegetal region by ß-catenin-TCF. (A) GATA transcriptional activity (G12 reporter mRNA, upper panel) and ß-catenin-TCF activity (Ci-foxD mRNA, lower panel) was visualized at the 16-cell stage in control, ß-catenin-MO- and TCF-MO-injected embryos. Lateral views, anterior to the left. Numbers indicate embryos with vegetal expression. (B) Bar chart of the mean number of positive cells per embryo in each condition in A (yellow is animal, blue is vegetal expression; error bars indicate confidence limits for P=0.05). (C) G12 reporter activity at the 110-cell stage in control, 100 mM and 200 mM LiCl-treated embryos. The x-axis represents the percentage of positive embryos; the y-axis indicates values at increasing concentrations of LiCl. The total numbers of embryos counted (n) are indicated at the bottom for each experimental condition. (D)Effect of GATAa-MO or Ci-GATAa mRNA injection on pFoxD activity at the 16-cell stage. Animal to the top, anterior to the left, numbers indicate the proportion of embryos with restricted vegetal expression.