Cervenka Igor, Valnohova Jana, Bernatik Ondrej, Harnos Jakub, Radsetoulal Matej, Sedova Katerina, Hanakova Katerina, Potesil David, Sedlackova Miroslava, Salasova Alena, Steinhart Zachary, Angers Stephane, Schulte Gunnar, Hampl Ales, Zdrahal Zbynek, Bryja Vitezslav
Department of Experimental Biology, Faculty of Science, Masaryk University, 61 137 Brno, Czech Republic;
Department of Experimental Biology, Faculty of Science, Masaryk University, 61 137 Brno, Czech Republic; Institute of Biophysics, Academy of Sciences of Czech Republic, 61 200 Brno, Czech Republic;
Proc Natl Acad Sci U S A. 2016 Aug 16;113(33):9304-9. doi: 10.1073/pnas.1608783113. Epub 2016 Aug 2.
Dishevelled (DVL) is a key scaffolding protein and a branching point in Wnt signaling pathways. Here, we present conclusive evidence that DVL regulates the centrosomal cycle. We demonstrate that DVL dishevelled and axin (DIX) domain, but not DIX domain-mediated multimerization, is essential for DVL's centrosomal localization. DVL accumulates during the cell cycle and associates with NIMA-related kinase 2 (NEK2), which is able to phosphorylate DVL at a multitude of residues, as detected by a set of novel phospho-specific antibodies. This creates interfaces for efficient binding to CDK5 regulatory subunit-associated protein 2 (CDK5RAP2) and centrosomal Nek2-associated protein 1 (C-NAP1), two proteins of the centrosomal linker. Displacement of DVL from the centrosome and its release into the cytoplasm on NEK2 phosphorylation is coupled to the removal of linker proteins, an event necessary for centrosomal separation and proper formation of the mitotic spindle. Lack of DVL prevents NEK2-controlled dissolution of loose centrosomal linker and subsequent centrosomal separation. Increased DVL levels, in contrast, sequester centrosomal NEK2 and mimic monopolar spindle defects induced by a dominant negative version of this kinase. Our study thus uncovers molecular crosstalk between centrosome and Wnt signaling.
散乱蛋白(DVL)是一种关键的支架蛋白,也是Wnt信号通路中的一个分支点。在此,我们提供确凿证据表明DVL调节中心体周期。我们证明,DVL的散乱和轴蛋白(DIX)结构域而非DIX结构域介导的多聚化对于DVL的中心体定位至关重要。在细胞周期中DVL会积累,并与NIMA相关激酶2(NEK2)结合,通过一组新型磷酸化特异性抗体检测发现,NEK2能够在多个残基上磷酸化DVL。这为与中心体连接蛋白的两种蛋白质——细胞周期蛋白依赖性激酶5调节亚基相关蛋白2(CDK5RAP2)和中心体Nek2相关蛋白1(C-NAP1)的有效结合创造了界面。NEK2磷酸化时,DVL从中心体移位并释放到细胞质中,这与连接蛋白的去除相关,而连接蛋白的去除是中心体分离和有丝分裂纺锤体正确形成所必需的事件。缺乏DVL会阻止NEK2控制的松散中心体连接的溶解及随后的中心体分离。相反,DVL水平升高会隔离中心体NEK2,并模拟由该激酶的显性负性版本诱导的单极纺锤体缺陷。因此,我们的研究揭示了中心体与Wnt信号之间的分子串扰。