Figure 1

Immunostained nervous system of developing mouse embryos. See [4] for the nerve staining method. (A) The head–trunk interface is drawn with an S-shaped red line, primarily based on [5]. Light blue indicates the position of cucullaris muscle development. (B) The head corresponds to the initial distribution domain of the cephalic crest cells where branchiomeric nerves are predominantly distributed, whereas the trunk domain is coextensive as somites whose derivatives are innervated by spinal nerves. Note that the spinal accessory nerve (XI) issues from the vagus in a close proximity of the interface. (C- H) Developmental changes of peripheral nerves of a mouse embryo. (C’-H’) Magnification of SAN and vagus nerve of each figure. Bars = 1 mm.