Phosphorylation statuses at different residues of lamin B2, B1, and A/C dynamically and independently change throughout the cell cycle
Phosphorylation statuses at different residues of lamin B2, B1, and A/C dynamically and independently change throughout the cell cycle
复制标题
DOI：
10.1016/j.yexcr.2010.05.017
复制
发表时间：
2010-08-15
影响因子：
3.7
通讯作者：
Tomonaga, Takeshi
中科院分区：
文献类型：
--
作者：
Kuga, Takahisa;Nozaki, Naohito;Tomonaga, Takeshi
核纤层蛋白是核纤层的主要成分，在细胞周期进程中在多个残基处进行磷酸化，但其详细的磷酸化动力学仍在很大程度上未确定。在这里，我们研究了主要的磷酸化残基（Thr 14，Ser 17，5er 385，Ser 387和Ser 401）的核纤层蛋白B2和核纤层蛋白B1，A/C的同源残基在细胞周期中使用新的抗体的位点特异性磷酸化的磷酸化的变化。这些残基的磷酸化水平在细胞周期中独立变化。Thr 14和Ser 17在G（2）/M期至后期/末期磷酸化。Ser 385在有丝分裂至G（1）期持续磷酸化，而Ser 387在分裂前期和G（1）期不连续磷酸化。Ser 401磷酸化在G（1）/S边界增强。使用磷酸化抗体的免疫沉淀表明，中期磷酸化在Thr 14，Ser 17，和Ser 385的核纤层蛋白同时发生，而G（1）-相磷酸化在Ser 385和Ser 387发生在不同的池或不同的时间。此外，我们发现，核纤层蛋白B2在Ser 17磷酸化，但不是Ser 385，Ser 387和Ser 401，是专门的非离子去污剂可溶性，解聚形式在生长中的细胞，这意味着具体参与的Ser 17磷酸化核纤层蛋白解聚和核膜破裂。这些结果提示核纤层蛋白不同残基的磷酸化可能在细胞周期中发挥特定的作用。(C)2010年爱思唯尔公司All rights reserved.
Lamins, major components of the nuclear lamina, undergo phosphorylation at multiple residues during cell cycle progression, but their detailed phosphorylation kinetics remain largely undetermined. Here, we examined changes in the phosphorylation of major phosphorylation residues (Thr14, Ser17, 5er385, Ser387, and Ser401) of lamin B2 and the homologous residues of lamin B1, A/C during the cell cycle using novel antibodies to the site-specific phosphorylation. The phosphorylation levels of these residues independently changed during the cell cycle. Thr14 and Ser17 were phosphorylated during G(2)/M phase to anaphase/telophase. Ser385 was persistently phosphorylated during mitosis to G(1) phase, whereas Ser387 was phosphorylated discontinuously in prophase and G(1) phase. Ser401 phosphorylation was enhanced in the G(1)/S boundary. Immunoprecipitation using the phospho-antibodies suggested that metaphase-phosphorylation at Thr14, Ser17, and Ser385 of lamins occurred simultaneously, whereas G(1)-phase phosphorylation at Ser385 and Ser387 occurred in distinct pools or with different timings. Additionally, we showed that lamin B2 phosphorylated at Ser17, but not Ser385, Ser387 and Ser401, was exclusively nonionic detergent soluble, depolymerized forms in growing cells, implicating specific involvement of Ser17 phosphorylation in lamin depolymerization and nuclear envelope breakdown. These results suggest that the phosphorylations at different residues of lamins might play specific roles throughout the cell cycle. (C) 2010 Elsevier Inc. All rights reserved.