XB-ART-1934Genes Dev May 1, 2005; 19 (9): 1022-7.
Default neural induction: neuralization of dissociated Xenopus cells is mediated by Ras/MAPK activation.
Xenopus embryonic ectodermal cells dissociated for three or more hours differentiate into neural tissue instead of adopting their normal epidermal fate. This default type of neural induction occurs in the absence of Spemann''s organizer signals and is thought to be caused by the dilution of endogenous BMPs into the culture medium. Unexpectedly, we observed that BMP ligands continue to signal in dissociated cells. Instead, cell dissociation induces a sustained activation of the Ras/MAPK pathway, which causes the phosphorylation of Smad1 at sites that inhibit the activity of this transcription factor. It is this activation of Ras/MAPK that is required for neuralization in dissociated ectoderm.
PubMed ID: 15879552
PMC ID: PMC1091736
Article link: Genes Dev
Genes referenced: bmp2 bmp4 bmp7.2 mapk1 smad1
Morpholinos: bmp2 MO1 bmp4 MO1 bmp7.2 MO1
References [+] :
Baker, Wnt signaling in Xenopus embryos inhibits bmp4 expression and activates neural development. 2000, Pubmed, Xenbase