Fig. 1

Neural crest and endothelial cells arise in distinct locations but share migratory pathways. a Top: schematic of head of St10 embryo indicating r4 axial level at which images below were acquired. Below: time course of transverse sections of quail at the indicated stages. Endothelial cells, QH1, green and neural crest, HNK1, purple. Scale bars 40 μm. Arrows point to the front of endothelial cells migrating along neural tube, and triangles point to endothelial cells branching off dorsal aorta towards neural crest stream. Transverse section of St11 (b) and HH St15 (c) QH1 and HNK1 stained quail highlighting proximity of neural crest and endothelial cells. Arrow highlighting one particularly close sprout to the neural crest stream. Scale bar 50 μm. d and e zoom in on b and c, respectively, with pair of close cells outlined. Arrow head pointing to endothelial cell sprout moving towards neural crest stream. Scale bar 50 μm. f Schematic of neural tube injection of DiI at St10, left and imaging at St15, right. Boxed region indicates area imaged in g–j. Red line indicates area viewed in h. g HH St15 stage transgenic quail embryo with DiI marking neural crest in magenta and the nuclei of endothelial cells marked in green. Scale bar 200 μm. h 90^o rotated view of BA2 and BA3 (red line in f) showing the central BA arteries and surrounding neural crest and endothelial cells. Scale bar 100 μm. i and j Same image as c with DiI and YFP channels separated