(A) Schematic of experimental overview. (B) In situ hybridization assaying expression of neural crest factors Snai2, FoxD3, and Sox10 in neurula (stage 15) embryos injected with inducible Sox2, Sox3, Sox9, or Sox10 constructs. (C) In situ hybridization assaying the expression of epidermal factor EPK in neurula (stage 15) embryos injected with inducible Sox2, Sox3, Sox9, or Sox10 constructs. Asterisk (*) denotes injected side of the embryo as marked by staining of the lineage tracer β-galactosidase (red).