Animal injection of Dse-MO did not affect the extent of the Sox2+ neural plate or Cytokeratin+ epidermis (Fig. S5A,B); however, it expanded the expression domains of the neural plate border markers Pax3 and Msx3 into the ventral ectoderm at stage 15 (Fig. 4B,C,E,F). DS-epi1 knockdown had no substantial effect on the Sox9 expression in the pre-migratory CNC (Fig. 4H,I); however, it reduced the levels of both the Foxd3 and Twist markers (Fig. 4K,L,N,P) and concomitantly expanded the c-Myc expression in these cells (Fig. 4R,T). The Dse-5MM-MO had no effect (Fig. 4A,D,G,J,M,Q), and the co-injection of Dse* mRNA and Dse-MO reverted the reduction of Twist and the expansion of the c-Myc expression (Fig. 4O,S,P,T), which supports the specificity of the phenotypes. Thus, DS-epi1 is not involved in the early dorsoventral ectoderm patterning; however, it controls the expression of neural-plate-border- and distinct CNC-specific transcription factors in neurula embryos.
