大肠杆菌染色体的多尺度结构通过核蛋白关联和凝蛋白
Virginia S Lioy1, Axel Cournac2, Martial Marbouty2
1Institut de Biologie Intégrative de la Cellule, CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
Cell
|January 24, 2018
概括
细菌基因组被组织成不同的结构域. 复制终点 (ter) 区域形成了一个单独的域,与其他染色体相比,不同的蛋白质控制了DNA接触.
科学领域:
- 微生物学
- 基因组学
- 分子生物学
背景情况:
- 细菌基因组,就像真核生物一样,表现出非随机折叠.
- 细菌染色体是圆形的,复制的来源是单一的,导致向终端 (ter) 区域的双向分叉.
研究的目的:
- 研究大肠杆菌基因组的高级结构.
- 阐明特定蛋白质在将细菌染色体组织成不同的领域中的作用.
主要方法:
- 在大肠杆菌中研究了高阶基因组结构.
- 分析了凝聚酶MukBEF,核相关蛋白 (NAPs) HU,MatP和H-NS的作用.
主要成果:
- 大肠杆菌基因组分为两个不同的结构实体:ter区域和其余的染色体.
- 在ter区域之外,MukBEF和HU蛋白调解大规模的DNA接触 (兆基范围).
- 在ter区域内,MatP抑制了MukBEF,限制接触到较小的域 (∼280 kb),而H-NS则限制了短距离相互作用.
结论:
- 像MatP和MukBEF这样的特定蛋白质在细菌染色体内产生不同的结构域.
- 核蛋白相关蛋白质在细菌染色体组织中起着至关重要的,进化保存的作用.
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