Fig. 1

Neural crest (sox10) and olfactory placode (six4b, dlx3b) markers have distinct but partially overlapping expression patterns. A–D:sox10 in situ hybridization (A,C) and anti-green fluorescent protein (GFP) immunocytochemistry (B,D) in sox10:EGFP embryos. At 5s (somite stage; A,B), sox10 mRNA expression (A) is similar to GFP expression (B), but at 14s–15s (C,D), GFP (D) is expressed in more cells than is sox10 mRNA (C). E,F: Double labeling of the olfactory placode (OP) field and cranial neural crest cells (CNCCs) in sox10:EGFP embryos at 2s. six4b (E, purple) and dlx3b (F, blue) are expressed in the OP field at 2s. Both genes are expressed in a horseshoe shape around rostral neural plate. six4b is more restricted than dlx3b. At this stage, the premigratory CNCCs (E,F, brown) flank the posterior domains of the six4b (E, purple) and dlx3b (F, blue) fields. A–D: Lateral view, rostral to the right, dorsal to the top of the page. E,F: Dorsal views, rostral to the top of the page. hpf, hour postfertilization. Scale bars = 100 μm in A–D, 100 μm in E,F.