Involvement of Wnt-1 in the formation of the mes/metencephalic boundary.
Wnt-1, a putative signaling molecule, is required before the 7 somite stage (E8.5) for the development of midbrain structures in the mouse. We show here that Wnt-1 is also needed for the formation of a boundary between the mesencephalic and metencephalic domains of the neural tube. In embryos homozygous for the Wnt-1sw allele, mesencephalic and metencephalic markers fail to segregate and the establishment of a straight limit of Otx-2 and Wnt-1 expression at the mid-hindbrain junction is impaired. In addition, as observed previously in heterotopic mes/metencephalic transplantation experiments in avian embryos, Wnt-1 expression is induced at the border of ectopic mes- and metencephalic islands observed in Wnt-1sw/sw mutants, suggesting that, in situ, interactions between mes- and metencephalic cells reinforce Wnt-1 expression at the boundary.
Bally-Cuif
L
L
INSERM U106, Hopital de la Salpêtrière, Paris, France.
Cholley
B
B
Wassef
M
M
D000818:Animals; D001483:Base Sequence; D002531:Cerebellum / Q000196:embryology; D002831:Choroid Plexus / Q000196:embryology; D004330:Drosophila / Q000196:embryology; D005314:Embryonic and Fetal Development / Q000502:physiology; D005865:Gestational Age; D006720:Homozygote; D008636:Mesencephalon / Q000196:embryology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010641:Phenotype; D011149:Pons / Q000196:embryology*; D011518:Proto-Oncogene Proteins / Q000502:physiology*; D051153:Wnt Proteins; D051155:Wnt1 Protein; D029961:Zebrafish Proteins
D011518:Proto-Oncogene Proteins; D051153:Wnt Proteins; D051155:Wnt1 Protein; C495246:Wnt1 protein, mouse; D029961:Zebrafish Proteins