Frizzled-7 signalling controls tissue separation during Xenopus gastrulation

Citation
R. Winklbauer et al., Frizzled-7 signalling controls tissue separation during Xenopus gastrulation, NATURE, 413(6858), 2001, pp. 856-860
Citations number
21
Categorie Soggetti
Multidisciplinary,Multidisciplinary,Multidisciplinary
Journal title
NATURE
ISSN journal
00280836 → ACNP
Volume
413
Issue
6858
Year of publication
2001
Pages
856 - 860
Database
ISI
SICI code
0028-0836(20011025)413:6858<856:FSCTSD>2.0.ZU;2-X
Abstract
Cell signalling through Frizzled receptors has evolved to considerable comp lexity within the metazoans. The Frizzled-dependent signalling cascade comp rises several branches, whose differential activation depends on specific W nt ligands, Frizzled receptor isoforms and the cellular context. In Xenopus laevis embryos, the canonical beta -catenin pathway contributes to the est ablishment of the dorsal-ventral axis(1). A different branch, referred to a s the planar cell polarity pathway, is essential for cell polarization duri ng elongation of the axial mesoderm by convergent extension(2). Here we dem onstrate that a third branch of the cascade is independent of Dishevelled f unction and involves signalling through trimeric G proteins and protein kin ase C (PKC). During gastrulation, Frizzled-7 (Fz7)-dependent PKC signalling controls cell-sorting behaviour in the mesoderm. Loss of zygotic Fz7 funct ion results in the inability of involuted anterior mesoderm to separate fro m the ectoderm, which leads to severe gastrulation defects. This result pro vides a developmentally relevant in vivo function for the Fz/PKC pathway in vertebrates.