Spatial ordering of chromosomes enhances the fidelity of chromosome partitioning in cyanobacteria
Spatial ordering of chromosomes enhances the fidelity of chromosome partitioning in cyanobacteria
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DOI：
10.1073/pnas.1211144109
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发表时间：
2012-08-21
影响因子：
11.1
通讯作者：
O'Shea, Erin K.
中科院分区：
文献类型：
--
作者：
Jain, Isha H.;Vijayan, Vikram;O'Shea, Erin K.
许多蓝细菌已被证明每个细胞含有多个染色体拷贝，但人们对这些染色体的组织、复制和分离知之甚少。在这里，我们通过延时荧光显微镜观察蓝藻细长聚球藻中的单个染色体。我们发现染色体沿细胞长轴等距分布，并散布着另一个规则间隔的亚细胞区室，即羧基体。这种非凡的细胞质组织以及准确的细胞中隔膜放置使得染色体与子细胞的分离达到近乎最佳的效果。染色体排序或中细胞隔膜放置的破坏会显着增加染色体分配误差。我们发现染色体复制是异步的并且独立于染色体在细胞中的位置，并且复制后空间组织得以保留。我们对 S. elongatus 染色体组织、复制和分离的研究结果为了解多染色体细菌的染色体动力学奠定了基础。
Many cyanobacteria have been shown to harbor multiple chromosome copies per cell, yet little is known about the organization, replication, and segregation of these chromosomes. Here, we visualize individual chromosomes in the cyanobacterium Synechococcus elongatus via time-lapse fluorescence microscopy. We find that chromosomes are equally spaced along the long axis of the cell and are interspersed with another regularly spaced subcellular compartment, the carboxysome. This remarkable organization of the cytoplasm along with accurate midcell septum placement allows for near-optimal segregation of chromosomes to daughter cells. Disruption of either chromosome ordering or midcell septum placement significantly increases the chromosome partitioning error. We find that chromosome replication is both asynchronous and independent of the position of the chromosome in the cell and that spatial organization is preserved after replication. Our findings on chromosome organization, replication, and segregation in S. elongatus provide a basis for understanding chromosome dynamics in bacteria with multiple chromosomes.