Display Settings:

Format

Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Cell Stem Cell. 2008 Nov 6;3(5):508-18. doi: 10.1016/j.stem.2008.09.013.

Wnt signaling mediates self-organization and axis formation in embryoid bodies.

Author information

  • 1Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA. derk@stanford.edu

Abstract

Embryonic stem cells (ESCs) form descendants of all three germ layers when differentiated as aggregates, termed embryoid bodies. In vivo, differentiation of cells depends on signals and morphogen gradients that provide instructive and positional cues, but do such gradients exist in embryoid bodies? We report here the establishment of anteroposterior polarity and the formation of a primitive streak-like region in the embryoid body, dependent on local activation of the Wnt pathway. In this region, cells undergo an epithelial-to-mesenchymal transition and differentiate into mesendodermal progenitors. Exogenous Wnt3a protein posteriorizes the embryoid body, resulting in predominantly mesendodermal differentiation. Conversely, inhibiting Wnt signaling promotes anterior character and results in neurectodermal differentiation. The activation of Wnt signaling and primitive streak formation requires external signals but is self-reinforcing after initiation. Our findings show that the Wnt pathway mediates the local execution of a gastrulation-like process in the embryoid body, which displays an unexpected degree of self-organization.

PMID:
18983966
[PubMed - indexed for MEDLINE]
PMCID:
PMC2683270
Free PMC Article

Images from this publication.See all images (7)Free text

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Write to the Help Desk