Fig. 5. Effects of suppression of Cs-FoxD function with specific morpholino on the differentiation of endoderm. (A,B) Histochemical detection of endoderm-specific alkaline phosphatase (Cs-AP) activity. (C,D) In situ hybridization examining expression of an endoderm-specific gene for thyroid hormone-receptor (Cs-THR). (A-D) Normal embryos; (B,D) control embryos arrested at the 110-cell stage. (A',B',C',D') Injection of Cs-FoxD morpholino into fertilized eggs: (A',C') injected embryos at the tailbud stage and (B',D') injected embryos arrested at the 110-cell stage. Arrowheads in D' indicate the expression of Cs-THR in presumptive notochord cells in addition to endoderm cells. Scale bars: in A, 100 µm for A',C,C'; in B, 100 µm for B',D,D'.