Loss of neural crest induced by xCdc4ΔFbox is rescued by co-injection of xCdc4. xCdc4ΔFbox mRNA (1 ng) was co-injected with either 1 ng of xCdc4 or 1 ng of GFP mRNA into one cell of two-cell-stage embryos. As controls, 1 ng of xCdc4 mRNA was co-injected with 1 ng of GFP mRNA, as well as injection of 2 ng of GFP mRNA as a separate control. β-gal mRNA was injected as a lineage tracer. (A-H) Embryos were allowed to develop to stages 18/19 and whole mount ISH was performed for the neural crest markers Snail2 (A-D) and Snail (E-H). Representative embryos are shown (anterior view, dorsal up, injected side right). Arrows indicate loss of expression of each marker on the injected side of xCdc4ΔFbox expressing embryos. The reduction in expression of each marker on the injected side of xCdc4ΔFbox expressing embryos is rescued by co-injection of xCdc4 mRNA (arrowheads).