Neural Induction in the Absence of Mesoderm: β-Catenin-Dependent Expression of Secreted BMP Antagonists at the Blastula Stage in Xenopus
A growing body of work indicates that neural induction may be initiated prior to the establishment of the gastrula mesodermal organizer. Here, we examine neural induction in Xenopus embryos in which mesoderm induction has been blocked by Cerberus-short, a reagent that specifically inhibits Nodal-related (Xnr) signals. We find that extensive neural structures with cyclopic eyes and brain tissue are