Department of Molecular Biology and Biochemistry, Graduate School of Medicine, Osaka University, Suita, Japan.
EMBO J. 2010 Apr 7;29(7):1192-204. doi: 10.1038/emboj.2010.26. Epub 2010 Mar 11.
Wnt5a is a representative ligand that activates the Wnt/beta-catenin-independent pathway, resulting in the regulation of cell adhesion, migration, and polarity, but its molecular mechanism is poorly understood. This report shows that Dishevelled (Dvl) binds to adenomatous polyposis coli (APC) gene product, and this binding is enhanced by Wnt5a. Dvl was involved in the stabilization of the plus end dynamics of microtubules as well as APC. Frizzled2 (Fz2) was present with Wnt5a at the leading edge of migrating cells and formed a complex with APC through Dvl. Fz2 also interacted with integrins at the leading edge, and Dvl and APC associated with and activated focal adhesion kinase and paxillin. The binding of APC to Dvl enhanced the localization of paxillin to the leading edge and was involved in Wnt5a-dependent focal adhesion turnover. Furthermore, this new Wnt5a signalling pathway was important for the epithelial morphogenesis in the three-dimensional culture. These results suggest that the functional and physical interaction of Dvl and APC is involved in Wnt5a/Fz2-dependent focal adhesion dynamics during cell migration and epithelial morphogenesis.
Wnt5a 是一种代表性配体,它能激活 Wnt/β-catenin 非依赖性途径,从而调节细胞黏附、迁移和极性,但该途径的分子机制尚不清楚。本报告显示,Dvl(Dishevelled)与腺瘤性结肠息肉病基因产物 APC(adenomatous polyposis coli)结合,而 Wnt5a 能增强这种结合。Dvl 参与微管正极动力学的稳定以及 APC 的稳定。Fz2(Frizzled2)与 Wnt5a 一起存在于迁移细胞的前缘,并通过 Dvl 与 APC 形成复合物。Fz2 还与前缘的整合素相互作用,Dvl 和 APC 与粘着斑激酶和桩蛋白结合并使之激活。APC 与 Dvl 的结合增强了 paxillin 向前缘的定位,并参与了 Wnt5a 依赖性粘着斑的周转。此外,这种新的 Wnt5a 信号通路对三维培养中的上皮形态发生很重要。这些结果表明,Dvl 和 APC 的功能和物理相互作用参与了 Wnt5a/Fz2 依赖性粘着斑动力学在细胞迁移和上皮形态发生中的作用。