Figure 6.

DiI and HNK1 labels neural crest cells. DiI (red) labeled st.21 snake embryo No.5 was double stained with HNK1 (green). A-C shows 1^st coil; D-I 2^nd coil, with D_F more rostral versus the G-I more caudal portion; and J-L the 3^rd coil. Each column shows either double channel, or just DiI or HNK1 staining. A-C DiI labeling of migrating crest was minimal, HNK1 faintly labeled some cells on the ventral portion of the trunk (white arrow). D-F shows strong DiI staining just above (white arrowhead) and in the mesonephroi, the point of injection in this embryo is marked as a large DiI spot. HNK1 staining labeled condensing peripheral ganglia, (white arrow), sympathetic ganglia (yellow arrow) and mesonephroi. G-H shows cells along the ventromedial pathway that are positive for both DiI and HNK1 (white arrows). DiI labeling also marked cells that now reached mesonephroi and are populating this tissue around (white arrowhead). J-L shows DiI-labeled cells that just delaminated from the neural tube but have not migrated (black arrows) as well as a small group of cells above the mesonephroi (white arrowhead). HNK1 labeled cells moving along the ventromedial pathway (white arrow) as well as the developing mesonephroi (yellow arrow). (The tail-most end of this embryo did not have DiI positive neural tube or migrating cells). R is for rostral; C is for caudal orientation in the embryo coils.