Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA.
EMBO J. 2012 May 18;31(14):3104-17. doi: 10.1038/emboj.2012.144.
Non-motile primary cilium is an antenna-like structure whose defect is associated with a wide range of pathologies, including developmental disorders and cancer. Although mechanisms regulating cilia assembly have been extensively studied, how cilia disassembly is regulated remains poorly understood. Here, we report unexpected roles of Dishevelled 2 (Dvl2) and interphase polo-like kinase 1 (Plk1) in primary cilia disassembly. We demonstrated that Dvl2 is phosphorylated at S143 and T224 in a manner that requires both non-canonical Wnt5a ligand and casein kinase 1 epsilon (CK1ɛ), and that this event is critical to interact with Plk1 in early stages of the cell cycle. The resulting Dvl2-Plk1 complex mediated Wnt5a-CK1ɛ-Dvl2-dependent primary cilia disassembly by stabilizing the HEF1 scaffold and activating its associated Aurora-A (AurA), a kinase crucially required for primary cilia disassembly. Thus, via the formation of the Dvl2-Plk1 complex, Plk1 plays an unanticipated role in primary cilia disassembly by linking Wnt5a-induced biochemical steps to HEF1/AurA-dependent cilia disassembly. This study may provide new insights into the mechanism underlying ciliary disassembly processes and various cilia-related disorders.
非运动性的初级纤毛是一种类似天线的结构,其缺陷与广泛的病理学有关,包括发育障碍和癌症。虽然调节纤毛组装的机制已经得到了广泛的研究,但纤毛解体的调节机制仍知之甚少。在这里,我们报告了 Dvl2(Dishevelled 2)和有丝分裂期 Polo 样激酶 1(Plk1)在初级纤毛解体中的意外作用。我们证明 Dvl2 在 S143 和 T224 处被磷酸化,这种方式需要非经典的 Wnt5a 配体和酪蛋白激酶 1ε(CK1ε),并且该事件对于在细胞周期的早期与 Plk1 相互作用至关重要。由此产生的 Dvl2-Plk1 复合物通过稳定 HEF1 支架和激活其相关的 Aurora-A(AurA)来介导 Wnt5a-CK1ε-Dvl2 依赖性初级纤毛解体,AurA 是初级纤毛解体所必需的激酶。因此,通过形成 Dvl2-Plk1 复合物,Plk1 通过将 Wnt5a 诱导的生化步骤与 HEF1/AurA 依赖性纤毛解体联系起来,在初级纤毛解体中发挥了意想不到的作用。本研究可能为纤毛解体过程和各种与纤毛相关的疾病的机制提供新的见解。