Ectomesenchymal and sympathetic neural crest is unaffected in pax3 morphants. In situ mRNA hybridisation for dlx2a (A), dbh (C) and immunodetection of HuC (B). Wholemounts in lateral (A upper panels,C; anterior to left and dorsal to top) or dorsal (A lower panels; anterior to left) view. Transverse sections of the foregut at hindbrain level are dorsal to top (B). A. At 24 hpf, dlx2a mRNA is detected in forebrain (black arrows) and branchial arch ectomesenchymal NC (white arrows) and is unaffected by pax3 MO injection. B. Bilateral sympathetic neurons (arrows) located between the notochord (NC) and ventral melanophore stripes are unaffected in a 5 dpf pax3 morphant lacking enteric neurons (arrowheads) around the gut. C. At 48 hpf in control embryos, dbh mRNA is present in cranial sympathetic neurons (asterisk), neurons of the dorsally located medulla oblongata (arrow) and the cervical sympathetic ganglia (arrowhead). In pax3 morphants, dbh mRNA is unaffected.
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