During vertebrate gastrulation, polarised cell behaviours orchestrated by Wnt/planar cell polarity (PCP) signalling drive the convergence and extension (C&E) movements that elongate the embryo. Xin Li, Florence Marlow, Lilianna Solnica-Krezel and colleagues now identify Gpr125, an adhesion G protein-coupled receptor, as a novel modulator of Wnt/PCP signalling during gastrulation in zebrafish embryos (). The researchers show that overexpression of Gpr125 impairs C&E movements in zebrafish embryos and that reduced Gpr125 function exacerbates the C&E defects and the facial branchiomotor neuron migration defects seen in embryos with reduced Wnt/PCP signalling. Gpr125 directly interacts with Dishevelled (Dvl), they report, and recruits Dvl to the cell membrane, a prerequisite for Wnt/PCP activation. Finally, they show that Gpr125 and Dvl mutually redistribute into discrete membrane subdomains and recruit a subset of PCP components into membrane subdomains. Thus, the researchers suggest, Gpr125 might act as a component of PCP membrane complexes and as a modulator of Wnt/PCP signalling in vertebrates.
