Strong intranucleoid interactions organize the Escherichia coli chromosome into a nucleoid filament
Strong intranucleoid interactions organize the Escherichia coli chromosome into a nucleoid filament
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强核内相互作用将大肠杆菌染色体组织成核丝
DOI：
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发表时间：
2010
影响因子：
11.1
通讯作者：
J. Kondev
中科院分区：
文献类型：
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作者：
Paul A. Wiggins;Keith C. Cheveralls;Joshua S. Martin;Robert E. Lintner;J. Kondev
用荧光标记法研究了活大肠杆菌细胞中基因位点的染色体组织的随机性。尽管通常假设染色体是由非结构化聚合物很好地模拟的，但对基因座分布的测量表明，大肠杆菌染色体精确地组织成具有线性顺序的类核丝。类核体中的位点在细胞内的定位精度优于细胞长度的10%。基因组近缘基因座间距离的精度优于细胞长度的4%。基因座间距离的精确测量依赖于基因组距离，单挑出核内相互作用作为负责染色体组织的机制。根据差异的大小，我们推断细菌中存在一种尚未表征的高阶DNA组织。我们证明了类核的随机和平均结构都是由波动弹性丝模型捕获的。
The stochasticity of chromosome organization was investigated by fluorescently labeling genetic loci in live Escherichia coli cells. In spite of the common assumption that the chromosome is well modeled by an unstructured polymer, measurements of the locus distributions reveal that the E. coli chromosome is precisely organized into a nucleoid filament with a linear order. Loci in the body of the nucleoid show a precision of positioning within the cell of better than 10% of the cell length. The precision of interlocus distance of genomically-proximate loci was better than 4% of the cell length. The measured dependence of the precision of interlocus distance on genomic distance singles out intranucleoid interactions as the mechanism responsible for chromosome organization. From the magnitude of the variance, we infer the existence of an as-yet uncharacterized higher-order DNA organization in bacteria. We demonstrate that both the stochastic and average structure of the nucleoid is captured by a fluctuating elastic filament model.