Galphaq negatively regulates the Wnt-beta-catenin pathway and dorsal embryonic Xenopus laevis development
Graduate School of Biomedical Sciences; Department of Cell Biology
Life Sciences | Medicine and Health Sciences
The non-canonical Wnt/Ca2+ signaling pathway has been implicated in the regulation of axis formation and gastrulation movements during early Xenopus laevis embryo development, by antagonizing the canonical Wnt/beta-catenin dorsalizing pathway and specifying ventral cell fate. However, the molecular mechanisms involved in this antagonist crosstalk are not known. Since Galphaq is the main regulator of Ca2+ signaling in vertebrates and from this perspective probably involved in the events elicited by the non-canonical Wnt/Ca2+ pathway, we decided to study the effect of wild-type Xenopus Gq (xGalphaq) in dorso-ventral axis embryo patterning. Overexpression of xGalphaq or its endogenous activation at the dorsal animal region of Xenopus embryo both induced a strong ventralized phenotype and inhibited the expression of dorsal-specific mesoderm markers goosecoid and chordin. Dorsal expression of an xGalphaq dominant-negative mutant reverted the xGalphaq-induced ventralized phenotype. Finally, we observed that the Wnt8-induced secondary axis formation is reverted by endogenous xGalphaq activation, indicating that it is negatively regulating the Wnt/beta-catenin pathway.
DOI of Published Version
J Cell Physiol. 2008 Feb;214(2):483-90. Link to article on publisher's site
Journal of cellular physiology
Soto X, Mayor R, Torrejon M, Montecino MA, Hinrichs MV, Olate J. (2007). Galphaq negatively regulates the Wnt-beta-catenin pathway and dorsal embryonic Xenopus laevis development. Morningside Graduate School of Biomedical Sciences Student Publications. https://doi.org/10.1002/jcp.21228. Retrieved from https://escholarship.umassmed.edu/gsbs_sp/1400