Du Jian, Chen Lijian, Luo Xin, Shen Yuxian, Dou Zhen, Shen Jilong, Cheng Li, Chen Ying, Li Chengjin, Wang Hua, Yao Xuebiao
Department of Biochemistry and Molecular Biology, Anhui Medical University, Hefei, China.
Front Biosci (Schol Ed). 2012 Jan 1;4(2):639-50. doi: 10.2741/s290.
Proteins of the 14-3-3 family are functionally conserved in eukaryotic kingdom which participates in diversified and critical cellular processes. However, the exact roles of these proteins in mitotic regulation has remained elusive. Polo-like kinase 1 (Plk1) is a serine/threonine protein kinase that plays multiple critical functions such as centrosome maturation, mitotic chromosome segregation, cytokinesis, and the DNA damage response. Here we show that 14-3-3zeta interacts and cooperates with Plk1 in mitotic progress. 14-3-3zeta is associated with the spindle at metaphase and concentrated in the midbody during cytokinesis. Using yeast two hybrid assay, we found a functional connection between 14-3-3zeta and Plk1. We demonstrate that phosphorylation of Plk1 at S330 and S597 promotes its interaction with 14-3-3zeta. Importantly, 14-3-3zeta cooperates with Plk1 in ensuring successful cytokinesis. We conclude that mitotic phosphorylation of Plk1 promotes interaction with 14-3-3zeta and this interaction is required for faithful cytokinesis. Taken together with the results of previous studies, our results suggest 14-3-3 family emerges as a novel player in mitotic regulation: cooperation with Plk1 to ensure a faithful cytokinesis.
14-3-3家族蛋白在真核生物界具有功能保守性，参与多种关键的细胞过程。然而，这些蛋白在有丝分裂调控中的具体作用仍不清楚。Polo样激酶1（Plk1）是一种丝氨酸/苏氨酸蛋白激酶，发挥多种关键功能，如中心体成熟、有丝分裂染色体分离、胞质分裂以及DNA损伤反应。在此我们表明，14-3-3ζ在有丝分裂进程中与Plk1相互作用并协同发挥作用。14-3-3ζ在中期与纺锤体相关联，在胞质分裂期间集中于中间体。利用酵母双杂交试验，我们发现了14-3-3ζ与Plk1之间的功能联系。我们证明，Plk1在S330和S597位点的磷酸化促进其与14-3-3ζ的相互作用。重要的是，14-3-3ζ与Plk1协同作用以确保胞质分裂成功。我们得出结论，Plk1的有丝分裂磷酸化促进其与14-3-3ζ的相互作用，并且这种相互作用对于准确的胞质分裂是必需的。结合先前研究的结果，我们的结果表明14-3-3家族成为有丝分裂调控中的一个新参与者：与Plk1协同作用以确保准确的胞质分裂。
