Deficiency in Chromosome Congression by the Inhibition of Plk1 Polo Box Domain-dependent Recognition
Deficiency in Chromosome Congression by the Inhibition of Plk1 Polo Box Domain-dependent Recognition
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DOI：
10.1074/jbc.m805308200
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发表时间：
2009-01-23
影响因子：
4.8
通讯作者：
Osada, Hiroyuki
中科院分区：
文献类型：
--
作者：
Watanabe, Nobumoto;Sekine, Tomomi;Osada, Hiroyuki
Polo样激酶1（Plk1）是有丝分裂细胞分裂的关键调节因子之一。Plk1除了在N端有一个蛋白激酶催化结构域外，在C端还有一个磷酸肽结合结构域，称为波罗box结构域（PBD）。PBD被认为是必不可少的Plk1定位和底物靶向。在这里，我们开发了一个高通量筛选系统来识别PBD依赖性结合的抑制剂，并筛选了一个化学文库。我们从五倍子中分离到一种含有苯并托酚酮的天然化合物（purpurogallin（PPG）），它在体外和体内抑制PBD依赖性结合。PPG不仅延迟HeLa细胞有丝分裂的开始，而且延长有丝分裂的进程。虽然明显正常的双极纺锤体形成，即使在PPG的存在下，扰动染色体排列在中期板激活纺锤体组装检查点途径。这些结果表明PBD依赖性结合在中期染色体平滑聚集中的主导作用。
Polo-like kinase 1 (Plk1) is one of the key regulators of mitotic cell division. In addition to an N-terminal protein kinase catalytic domain, Plk1 possesses a phosphopeptide binding domain named polo box domain (PBD) at its C terminus. PBD is postulated to be essential for Plk1 localization and substrate targeting. Here, we developed a high-throughput screening system to identify inhibitors of PBD-dependent binding and screened a chemical library. Weisolated a benzotropolone-containing natural compound derived from nutgalls (purpurogallin (PPG)) that inhibited PBD-dependent binding in vitro and in vivo. PPG not only delayed the onset of mitosis but also prolonged the progression of mitosis in HeLa cells. Although apparently normal bipolar spindles were formed even in the presence of PPG, the perturbation of chromosome alignment at metaphase plates activated the spindle assembly checkpoint pathway. These results demonstrate the predominant role of PBD-dependent binding on smooth chromosome congression at metaphase.