Fig. 6

Defects in Convergence, but Not in Dorsoventral Patterning, Are Synergistically Enhanced upon Combined Loss of Chordin and N-Cadherin and in bmp2b Heterozygotes after Moderate n-cadherin Overexpression. (A–D) Lateral overviews of live embryos of indicated genotype at 24 hpf (cdh2 allele pac^fr7; chd allele din^tt250) (E, F, I, J, M, N) Live embryos with fluorescently labeled mesoderm cells at the onset and end of gastrulation. Coinjection of small amounts of cdh2-MO and chd-MO in wild-type embryos (J) or injection of small amounts of cdh2-mRNA in bmp2b^+/- embryos (N) lead to a synergistic enhancement of the defects in convergence movements. (G, H, K, L) Same embryos as shown in (E), (F), (I), (J), at 5-somite stage and after in situ hybridizations for six3b (left, animal views), a marker for anterior neuroectoderm, and szl (right, vegetal views), a marker for posterior mesoderm. The chd/cdh2 double morphant (L) displays a six3b expression domain not smaller than that of the chd single morphant (K), and a szl domain not larger than that of the chd morphant, indicating that the ventralization caused by loss of Chd is not further enhanced by the simultaneous loss of Cdh2.