Figure 4.

Lamprey Dlx gene expression in the cranial neural crest. Whole mounts and transverse sections of the head regions of 9-day-old lamprey embryos labeled with DlxA, DlxC, and DlxD riboprobes (DlxB expression is not detected at this stage). (×150.) DlxA and DlxD are both expressed in the dorsal aspect of the neural tube (D and F, arrowheads), as well as in ectomesenchyme consistent with migrating neural crest (arrows). DlxC is not detected in the neural tube, but is detected in head ectomesenchyme (E, arrows). Lines labeled by lowercase letters d, e, and f indicate sectioning planes.