Department of Cell, Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
J Cell Sci. 2021 Dec 15;134(24). doi: 10.1242/jcs.258864.
The orientation of epithelial cells in the plane of the tissue, known as planar cell polarity (PCP), is regulated by interactions of asymmetrically localized PCP protein complexes. In the Xenopus neural plate, Van Gogh-like2 (Vangl2) and Prickle3 (Pk3) proteins form a complex at the anterior cell boundaries, but how this complex is regulated in vivo remains largely unknown. Here, we use proximity biotinylation and crosslinking approaches to show that Vangl2-Pk3 association is inhibited by Frizzled3 (Fz3, also known as Fzd3), a core PCP protein that is specifically expressed in the neuroectoderm and is essential for the establishment of PCP in this tissue. This inhibition required Fz3-dependent Vangl2 phosphorylaton. Consistent with our observations, the complex of Pk3 with nonphosphorylatable Vangl2 did not polarize in the neural plate. These findings provide evidence for in vivo regulation of Vangl2-Pk3 complex formation and localization by a Frizzled receptor.
上皮细胞在组织平面上的取向,即平面细胞极性(PCP),受不对称定位的 PCP 蛋白复合物的相互作用调节。在非洲爪蟾神经板中,Van Gogh-like2(Vangl2)和 Prickle3(Pk3)蛋白在前细胞边界形成复合物,但该复合物在体内如何被调节在很大程度上仍是未知的。在这里,我们使用邻近生物素化和交联方法表明,Frizzled3(Fz3,也称为 Fzd3)抑制了 Vangl2-Pk3 复合物的形成,Fz3 是 PCP 的核心蛋白,特异性表达于神经外胚层,对于在该组织中建立 PCP 是必需的。这种抑制需要 Fz3 依赖性的 Vangl2 磷酸化。与我们的观察结果一致,非磷酸化 Vangl2 与 Pk3 的复合物在神经板中没有极化。这些发现为 Frizzled 受体对 Vangl2-Pk3 复合物形成和定位的体内调节提供了证据。