Figure 5. Snail1 or N-cadherin rescues neural crest migration in the Elp3 morphants.

(a–f) Co-injection with mSnail1 mRNA (0.5 ng) rescues the migration of neural crest cells in the Elp3 morphants. (g) Percentages of embryos with reduced migration of neural crest as shown in (a–f). The results are from three independent experiments (error bars represent SDs). (h,i) Knockdown of Elp3 by morpholino down-regulates the N-cadherin level, while co-injection with Elp3 mRNA (0.2 ng) restores its expression. (j) Percentages of embryos with reduced expression of N-cadherin as shown in (h,i). The results are from three independent experiments (error bars represent SDs). (k) The expression levels of N-cadherin in embryos injected with Elp3 morpholino and Elp3 mRNA at St 13. Both cells of the 2-cell stage embryos were injected with Elp3 morpholino (12.5 ng/cell) alone, together with rescue mRNA (0.1 ng/cell), or Elp3 mRNA (0.5 ng/cell) alone. Total RNAs from whole embryos were subjected to RT-PCR analysis for the expression of the indicated genes (cycle numbers: ODC, 24; N-cadherin, 32). (l) Elp3 is required for the expression of N-cadherin in induced animal caps. The embryos were injected animally at 2-cell stage with tBR (0.2 ng/embryo) and Wnt7b (0.5 ng/embryo) to induce neural crest fate. Elp3 morpholino and/or mRNA were co-injected as indicated. Animal caps were dissected at stage 9 and harvested when control embryos reached St 19–21. Total RNAs from the animal caps were subjected to RT-PCR analysis for the expression of the indicated genes (cycle numbers: histone H4, 24; N-cadherin, 31). (m–p) Co-injection with mN-cadherin mRNA (0.1 ng) rescues the migration of neural crest cells. LacZ mRNA was co-injected to trace the injected sides (stained red on the right sides). (q) Percentages of embryos with reduced migration of neural crest as shown in (m–p). The results are from three independent experiments (error bars represent SDs).