GSBS Student Publications

Title

Galphaq negatively regulates the Wnt-beta-catenin pathway and dorsal embryonic Xenopus laevis development

UMMS Affiliation

Graduate School of Biomedical Sciences; Department of Cell Biology

Date

7-27-2007

Document Type

Article

Medical Subject Headings

Animals; *Body Patterning; Embryo, Nonmammalian; Embryonic Development; GTP-Binding Protein alpha Subunits, Gq-G11; Gastrulation; *Gene Expression Regulation, Developmental; Wnt Proteins; Xenopus laevis; beta Catenin

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

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.

Rights and Permissions

Citation: J Cell Physiol. 2008 Feb;214(2):483-90. Link to article on publisher's site

Related Resources

Link to Article in PubMed

Journal Title

Journal of cellular physiology

PubMed ID

17654482