A, Experimental scheme for induction of sox10:GFP in neuralized ectoderm. B-G, Ectoderm explants were prepared at stage 10 from Tg(sox10:GFP) embryos injected with chordin RNA (150 pg, C) alone, or in combination with wnt8 (0.8 ng, D), wnt11a (1 ng, E), wnt5a (1 ng, F), and wnt11b (1 ng, G) RNAs as indicated. The explants were cultured until the equivalent of stage 26 and imaged (B-G) or lysed for RT-PCR (H). H, GFP reporter is activated in transgenic ectoderm explants by chordin and wnt8 RNAs. I, Frequencies of GFP-positive caps (%). Total number of explants is shown above each bar.