斑馬魚 arl6ip1 參與胚胎神經脊細胞發育之角色

Although the embryonic expression pattern of ADP ribosylation factor-like 6 interacting protein 1(Arl6ip1) has been reported, the function that Alr6ip1 plays in neural crest development is unclear. We found that knockdown of Arl6ip1 caused defective neural crest derivatives in embryos, particularly more severe in craniofacial cartilages. Expressions of neural plate border specifier genes msxb, dlx3b, and pax3 were normal, but the expressions of the neural crest specifier genes foxd3, snai1b, and sox10 were greatly reduced. These findings suggest that arl6ip1 is essential for neural crest specification, but not neural crest induction. Furthermore, we revealed that the streams of crestin- and sox10-expressing neural crest cells which migrate ventrally from neural tube into trunk were disrupted in arl6ip1 morphants. This migration defect was not only in the trunk neural crest, but also in the enteric tract where the vagal-derived neural crest cells failed to populate the enteric nervous system. These data further suggested that arl6ip1 is required for neural crest migration. Finally, we proved that apoptosis is not attributed to the loss of neural crest cells , confirmed by double staining of TUNEL and crestin. Therefore, we concluded that arl6ip1 is required for neural crest specification and migration.