(A) Schematic of experimental overview for knockdown experiments. (B) In situ hybridization examining Sox9, Sox10, or FoxD3 expression in animal pole explants injected with Sox10 morpholino, Wnt8, and chordin. (C) Schematic of experimental overview for rescue experiments. (D) In situ hybridization examining FoxD3 expression in animal pole explants injected with Sox10 morpholino, Wnt8, chordin, and either Sox2 or Sox9 mRNA. (E) In situ hybridization examining FoxD3 expression in animal pole explants injected with Sox10 morpholino, Wnt8, chordin, and either Sox3 or Sox10.