Defined chromosome structure in the genome-reduced bacterium Mycoplasma pneumoniae.
Defined chromosome structure in the genome-reduced bacterium Mycoplasma pneumoniae.
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DOI：
10.1038/ncomms14665
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发表时间：
2017-03-08
影响因子：
16.6
通讯作者：
Serrano L
中科院分区：
文献类型：
--
作者：
Trussart M;Yus E;Martinez S;Baù D;Tahara YO;Pengo T;Widjaja M;Kretschmer S;Swoger J;Djordjevic S;Turnbull L;Whitchurch C;Miyata M;Marti-Renom MA;Lluch-Senar M;Serrano L
DNA结合蛋白是染色体组织的中心调节因子;然而，在基因组减少的细菌中，它们的多样性大大减少。这种细菌的染色体是否采用了确定的三维结构仍然没有被探索。在这里，我们结合联合收割机Hi-C和超分辨率显微镜，以确定肺炎支原体染色体的结构在10 kb的分辨率。我们发现了一个明确的结构，在连接相反两极的两个臂之间具有全局对称性，一个臂具有染色体Ori，另一个臂具有中点。在3 kb分辨率的局部结构分析表明，染色体被组织成范围从15至33 kb的域。我们提供的证据表明，在同一个领域内的基因往往是共同调节，这表明染色体组织影响转录调控，超螺旋调节当地的组织。这项研究扩展了目前对细菌基因组组织的理解，并证明了确定的染色体结构是生命系统的普遍特征。基因组减少的细菌的三维结构知之甚少。在这里，作者将联合收割机Hi-C与肺炎支原体的超分辨率显微镜相结合，并提供了超螺旋和局部组织如何影响基因调控的证据。
DNA-binding proteins are central regulators of chromosome organization; however, in genome-reduced bacteria their diversity is largely diminished. Whether the chromosomes of such bacteria adopt defined three-dimensional structures remains unexplored. Here we combine Hi-C and super-resolution microscopy to determine the structure of the Mycoplasma pneumoniae chromosome at a 10 kb resolution. We find a defined structure, with a global symmetry between two arms that connect opposite poles, one bearing the chromosomal Ori and the other the midpoint. Analysis of local structures at a 3 kb resolution indicates that the chromosome is organized into domains ranging from 15 to 33 kb. We provide evidence that genes within the same domain tend to be co-regulated, suggesting that chromosome organization influences transcriptional regulation, and that supercoiling regulates local organization. This study extends the current understanding of bacterial genome organization and demonstrates that a defined chromosomal structure is a universal feature of living systems. The three-dimensional architecture of genome-reduced bacteria is poorly understood. Here the authors combine Hi-C with super-resolution microscopy in Mycoplasma pneumoniae and provide evidence of how supercoiling and local organization influences gene regulation.