Wnt6 controls amniote neural crest induction through the non-canonical signaling pathway.
The neural crest is a multipotent embryonic cell population that arises from neural ectoderm and forms derivatives essential for vertebrate function. Neural crest induction requires an ectodermal signal, thought to be a Wnt ligand, but the identity of the Wnt that performs this function in amniotes is unknown. Here, we demonstrate that Wnt6, derived from the ectoderm, is necessary for chick neural crest induction. Crucially, we also show that Wnt6 acts through the non-canonical pathway and not the beta-catenin-dependant pathway. Surprisingly, we found that canonical Wnt signaling inhibited neural crest production in the chick embryo. In light of studies in anamniotes demonstrating that canonical Wnt signaling induces neural crest, these results indicate a significant and novel change in the mechanism of neural crest induction during vertebrate evolution. These data also highlight a key role for noncanonical Wnt signaling in cell type specification from a stem population during development.
Department of Veterinary Basic Sciences, Royal Veterinary College, London, United Kingdom.
Corina
C
Schmidt
Imelda M
IM
McGonnell
Steve
S
Allen
Anthony
A
Otto
Ketan
K
Patel
D000111:Acetylcysteine / Q000378:metabolism; D000650:Amnion / Q000502:physiology*; D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D015509:Developmental Biology / Q000379:methods*; D018274:Electroporation; D018507:Gene Expression Regulation, Developmental; D008024:Ligands; D051379:Mice; D008954:Models, Biological; D041681:NIH 3T3 Cells; D009432:Neural Crest / Q000196:embryology* / Q000378:metabolism; D015398:Signal Transduction; D051153:Wnt Proteins / Q000235:genetics* / Q000502:physiology*
D008024:Ligands; D051153:Wnt Proteins; D000111:Acetylcysteine