Figure 3. Experiments with Xenopus embryos.

Stage numbers are denoted with an X to distinguish them from the axolotl stage numbers shown in Fig. 2. Embryos injected with dnXWnt11 (column X2) or dnDsh constructs (column X3) or injected unilaterally with dnXWnt11 (column X4) are compared to controls (column X1) of the same clutch at developmental stages 12.5 (early neurulation), 14, 15, and 17 (late neurulation). Injected embryos show developmental defects including large and irregularly shaped neural plates, enlarged neural folds, and delayed neural fold migration. The manually overlaid colors correspond to those in Figs. 24.