Feedback control of chromosome separation by a midzone Aurora B gradient.
Feedback control of chromosome separation by a midzone Aurora B gradient.
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DOI：
10.1126/science.1251121
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发表时间：
2014-07-18
期刊：
影响因子：
--
通讯作者：
Maiato H
中科院分区：
文献类型：
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作者：
Afonso O;Matos I;Pereira AJ;Aguiar P;Lampson MA;Maiato H
有丝分裂过程中准确的染色体分离需要在核膜重组（NER）之前姐妹染色单体的物理分离。然而，这两个过程如何协调仍然未知。在这里，我们发现了一种保守的反馈控制机制，该机制延迟了染色体去致密化和NER，以响应后期染色体不完全分离。研究发现，中间区相关的Aurora B梯度监测染色体沿分裂轴的位置，并通过保留凝缩蛋白i来防止染色体过早去浓缩。PP1/PP2A磷酸酶抵消了这种梯度，促进染色体去浓缩和NER。因此，极光B梯度似乎介导了一种监视机制，阻止染色体去浓缩和NER，直到姐妹染色单体的有效分离实现。这允许在NER完成之前主核中滞后染色体的校正和重新整合。
Accurate chromosome segregation during mitosis requires the physical separation of sister chromatids before nuclear envelope reassembly (NER). However, how these two processes are coordinated remains unknown. Here, we identified a conserved feedback control mechanism that delays chromosome decondensation and NER in response to incomplete chromosome separation during anaphase. A midzone-associated Aurora B gradient was found to monitor chromosome position along the division axis and to prevent premature chromosome decondensation by retaining Condensin I. PP1/PP2A phosphatases counteracted this gradient and promoted chromosome decondensation and NER. Thus, an Aurora B gradient appears to mediate a surveillance mechanism that prevents chromosome decondensation and NER until effective separation of sister chromatids is achieved. This allows the correction and reintegration of lagging chromosomes in the main nuclei before completion of NER.