...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Current Biology: CB >Nuclear Geometry and Rapid Mitosis Ensure Asymmetric Episome Segregation in Yeast
【24h】

Nuclear Geometry and Rapid Mitosis Ensure Asymmetric Episome Segregation in Yeast

机译：核几何和快速有丝分裂确保酵母中不对称附加体的分离

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Background: Asymmetric cell division drives the generation of differentiated cells and maintenance of stem cells. In budding yeast, autonomously replicating sequence (ARS) plasmids lacking centromere elements are asymmetrically segregated into the mother cell, where they are thought to contribute to cellular senescence. This phenomenon has been proposed to result from the active retention of plasmids through an interaction with nuclear pores. Results: To investigate the mother-daughter segregation bias of plasmids, we used live-cell imaging to follow the behavior of extrachromosomal DNA. We show that both an excised DNA ring and a centromere-deficient ARS plasmid move freely in the nucleoplasm yet show a strong segregation bias for the mother cell. Computational modeling shows that the geometrical shape of the dividing yeast nucleus and length of mitosis severely restrict the passive diffusion of episomes into daughter nuclei. Predictions based on simulated nuclear division were tested with mutants that extend the length of mitosis. Finally, explaining how various anchors can improve mitotic segregation, we show that plasmid partitioning is improved by tethering the plasmid to segregating structures, such as the nuclear envelope and telomeres. Conclusions: The morphology and brevity of mitotic division in budding yeast impose physical constraints on the diffusion of material into the daughter, obviating the need for a retention mechanism to generate rejuvenated offspring. Highlights: Asymmetric plasmid segregation in yeast stems from cell morphology and mitotic timing Prolonging the time of mitosis increases the efficiency of plasmid segregation Tethering plasmids to telomeres or the nuclear envelope facilitates segregation No active mechanism of retention is required to explain episome asymmetry in yeast
机译：背景：不对称细胞分裂驱动分化细胞的生成和干细胞的维持。在出芽的酵母中，缺少着丝粒元素的自主复制序列（ARS）质粒不对称地分离到母细胞中，据认为它们有助于细胞衰老。已经提出这种现象是由于质粒通过与核孔的相互作用而主动保留而导致的。结果：为了研究质粒的​​母女分离偏倚，我们使用了活细胞成像来追踪染色体外DNA的行为。我们显示，既切除的DNA环和着丝粒缺陷型ARS质粒在核质中自由移动，但对母细胞显示强烈的偏倚。计算模型表明，分裂的酵母核的几何形状和有丝分裂的长度严重限制了附加体向子核的被动扩散。基于模拟核分裂的预测用扩展有丝分裂长度的突变体进行了测试。最后，解释各种锚点如何改善有丝分裂的分离，我们表明通过将质粒束缚于分离结构（如核被膜和端粒）可以改善质粒的分配。结论：发芽酵母中有丝分裂的形态和简洁性对物质向子代中的扩散施加了物理限制，从而消除了需要保留机制来产生再生后代的需求。亮点：酵母中不对称的质粒分离源于细胞的形态和有丝分裂的时机延长有丝分裂的时间可以提高质粒分离的效率将质粒束缚到端粒或核被膜上有助于分离不需要附加的活性机制来解释酵母中的附加体不对称

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号