Biphasic role for Wnt/beta-catenin signaling in cardiac specification in zebrafish and embryonic stem cells

Proc Natl Acad Sci U S A. 2007 Jun 5;104(23):9685-90 pdf

Ueno S, Weidinger G, Osugi T, Kohn AD, Golob JL, Pabon L, Reinecke H, Moon RT, Murry CE.

Understanding pathways controlling may offer insights that are useful for stem cell-based cardiac repair. Developmental studies indicate that the pathway negatively regulates cardiac differentiation, whereas studies with pluripotent embryonal carcinoma cells suggest that this pathway promotes cardiogenesis. This apparent contradiction led us to hypothesize that Wnt/beta-catenin signaling acts biphasically, either promoting or inhibiting cardiogenesis depending on timing. We used inducible promoters to activate or repress Wnt/beta-catenin signaling in zebrafish embryos at different times of development. We found that Wnt/beta-catenin signaling before gastrulation promotes cardiac differentiation, whereas signaling during gastrulation inhibits heart formation. Early treatment of differentiating mouse embryonic stem (ES) cells with stimulates induction, activates a feedback loop that subsequently represses the Wnt pathway, and increases cardiac differentiation. Conversely, late activation of beta-catenin signaling reduces cardiac differentiation in ES cells. Finally, constitutive overexpression of the beta-catenin-independent ligand increases cardiogenesis in differentiating mouse ES cells. Thus, Wnt/beta-catenin signaling promotes cardiac differentiation at early developmental stages and inhibits it later. Control of this pathway may promote derivation of for basic research and cell therapy applications.

Laisser un commentaire

Entrez vos coordonnées ci-dessous ou cliquez sur une icône pour vous connecter:

Logo WordPress.com

Vous commentez à l'aide de votre compte WordPress.com. Déconnexion / Changer )

Image Twitter

Vous commentez à l'aide de votre compte Twitter. Déconnexion / Changer )

Photo Facebook

Vous commentez à l'aide de votre compte Facebook. Déconnexion / Changer )

Photo Google+

Vous commentez à l'aide de votre compte Google+. Déconnexion / Changer )

Connexion à %s

%d blogueurs aiment cette page :