<i>Dlx2</i> expression in neural crest cells in the catshark.

<p><b>A–E</b>: lateral views of whole-mount embryos, anterior is to the top, dorsal to the right, between stage 17 and 21. <b>F</b>: schematic of the head for embryo in panel B with location (blue colored) of the various streams of migrating neural crest cells: trigeminal (tg) stream separated in the premandibular (pm) and the mandiblar (m) streams; hyoid (h) stream; branchial (b) stream. <b>G–K</b> are transverse sections made on the embryo shown in panel B. The section level is located on panel F: G = section 1(S1) to K = section 5 (S5). <b>A</b>: stage 17, expression is restricted to the neural crest cells both at the cranial and trunk level. <b>B</b>: streams of cranial neural crest cells migrate ventrally: <i>Dlx2</i> expression detected in the various cranial neural crest streams and most posteriorly in the trunk neural crest cells (tnc). <b>D, E</b>: after migration, <i>Dlx2</i>-positive cells are found in the mesenchyme of branchial arches (ba). ba1: first branchial arch, ba2: second branchial arch, oc: optic vesicle, nt: neural tube. Scale bars: A–E: 200 µm; G–K: 100 µm.