Wnt-regulated temporal control of BMP exposure directs the choice between neural plate border and epidermal fate.
The non-neural ectoderm is divided into neural plate border and epidermal cells. At early blastula stages, Wnt and BMP signals interact to induce epidermal fate, but when and how cells initially acquire neural plate border fate remains poorly defined. We now provide evidence in chick that the specification of neural plate border cells is initiated at the late blastula stage and requires both Wnt and BMP signals. Our results indicate, however, that at this stage BMP signals can induce neural plate border cells only when Wnt activity is blocked, and that the two signals in combination generate epidermal cells. We also provide evidence that Wnt signals do not play an instructive role in the generation of neural plate border cells, but promote their generation by inducing BMP gene expression, which avoids early simultaneous exposure to the two signals and generates neural plate border instead of epidermal cells. Thus, specification of neural plate border cells is mediated by a novel Wnt-regulated BMP-mediated temporal patterning mechanism.
Patthey
Cédric
C
Umeå Center for Molecular Medicine, Building 6M, 4th floor, Umeå University, S-901 87 Umeå, Sweden.
Edlund
Thomas
T
Gunhaga
Lena
L
D000818:Animals; D036703:Blastula / Q000166:cytology / Q000187:drug effects; D019521:Body Patterning / Q000187:drug effects; D055415:Bone Morphogenetic Protein 4 / Q000235:genetics / Q000378:metabolism; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D019070:Cell Lineage / Q000187:drug effects*; D002645:Chickens; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D005855:Germ Layers / Q000166:cytology / Q000187:drug effects; D006801:Humans; D051379:Mice; D008954:Models, Biological; D009432:Neural Crest / Q000166:cytology / Q000187:drug effects; D054258:Neural Plate / Q000166:cytology* / Q000187:drug effects*; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D051153:Wnt Proteins / Q000378:metabolism*
D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D051153:Wnt Proteins