Fig. 7. Effects of functional suppression of Cs-lhx3 with morpholino oligos, rescue of the suppression by injection of synthetic Cs-lhx3 mRNA or overexpression of Ci-lhx3 on endodermal cell differentiation. (A,B) The embryos developed from eggs injected with morpholino against Cs-lhx3. Cs-lhx3 morpholino inhibits development of AP activity (A) and endoderm-specific thyroid hormone receptor gene expression (B). Insert in B shows the endoderm-specific expression of thyroid hormone receptor gene in control embryo (arrow). (C,D) Co-injection of Cs-lhx3 morpholino together with lacZ mRNA (C) or Cs-lhx3 mRNA (D). In control, AP activity did not develop (C), but embryos developed from eggs injected with Cs-lhx3 morpholino and synthetic mRNA showed AP activity (D). (E,F) Effects of Cs-lhx3 overexpression. AP expression in embryos developed from eggs injected with Cs-lhx3 mRNA or lacZ mRNA (control) and arrested at the 110-cell stage, vegetal view. (E) Control embryo showing AP activity in blastomeres of the endoderm lineage, while (F) Cs-lhx3 overexpressed embryos showing AP activity in non-endodermal blastomeres as well. Arrowheads indicate pigment cell development in the cleavage-arrested embryo. (G) AP expression in embryos developed from eggs injected with delE-Ci-cadherin mRNA and lacZ mRNA. (H) AP expression in embryos developed from eggs injected with delE-Ci-cadherin mRNA and Cs-lhx3 mRNA. Scale bars: in A, 100 µm for A-D; in E, 100 µm for E,F; in G, 100 µm for G,H.