Ednras are required for patterning of ventral cranial NC. Whole-mount RNA in situ hybridization; 30 hpf dorsolateral views (A-H), lateral views (I-P). (A) dlx2a marks cranial NC cells along the DV axis of the arches, which remains unchanged in Ednra1 (B) or Ednra2 (C) morphants. (D) In Ednra1;Ednra2 double morphants, dlx2a is reduced in the ventral NC of arch 1 and 2 (asterisks). (E) hand2 marks rings of ventral NC in the arches, which remain in Ednra1 (F) or Ednra2 (G) morphants and are lost in Ednra1;Ednra2 double morphants (asterisks), except in small cell groups at arch borders (H). (I) At 44 hpf, gsc marks separate dorsal (D1, D2) and ventral (V1, V2) NC domains in the mandibular and hyoid arches, which remain unaffected in Ednra2 morphants (K). (J) In Ednra1 morphants, these domains remain distinct, although the distance between them is reduced. (L) In Ednra1;Ednra2 double morphants, gsc is dramatically reduced in the ventral mandibular (asterisk) and hyoid arches. (M) At 30 hpf, eng2 marks dorsal muscle precursors in the mandibular arch, which are unaffected in Ednra2 morphants (O). (N) In Ednra1 morphants eng2 extends ventrally. (P) In Ednra1;Ednra2 double morphants, eng2 expression spreads both along the DV and anteroposterior axes. Scale bars: 25 μm.
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