Xenbase Image ID: 131431

FIG. 7. Model for organizer induction. The diagram indicates three steps in the establishment of a dorsal signaling center. At the blastula stage, nuclear b-Catenin (dotted area) induces the early zygotic expression of organizer-specific genes (black), such as chordin, noggin, follistatin, and Xnr3 in the preorganizer region. These BMP antagonists may participate in the predetermination of the neural plate. Later, Nodal signals originating from vegetal cells (hatched area) are required for the induction of mesoderm and for maintenance of organizer gene expression. At the gastrula stage, the same cocktail of factors secreted by the mature Spemann’s organizer will pattern all three germ layers and is maintained by Nodal-related signals produced from within the mesoderm (hatched area). Image published in: Wessely O et al. (2001) Copyright © 2001. Image reproduced with permission of the Publisher, Elsevier B. V. Larger Image Printer Friendly View

Return to previous page