在最小的细菌细胞中染色体组织的动力学
Benjamin R Gilbert1, Zane R Thornburg1, Troy A Brier1
1Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL, United States.
Frontiers in cell and developmental biology
|August 25, 2023
概括
现在的计算模型包括细菌染色体复制和分离. 模拟表明,只有必需蛋白质才能驱动染色体组织和细胞分裂,支持通用循环挤出机制.
科学领域:
- 计算生物学是一种计算生物学.
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
背景情况:
- 准确的细胞计算模型需要结合遗传物质的复制和遗传.
- 现有的全细胞模型 (WCMs) 需要扩展,以涵盖整个细胞周期,包括染色体动态.
研究的目的:
- 开发一个计算框架,以高分辨率建模细菌染色体复制和组织.
- 为JCVI-syn3A扩展现有的WCM,以模拟整个细胞周期,专注于染色体动力学.
- 研究重要蛋白质在染色体分离和组织中的作用.
主要方法:
- 模拟复制细菌染色体作为聚合物使用布朗动力学在10bp分辨率.
- 整合曲和扭曲刚度来表示DNA的机械性质,并避免核糖体重叠.
- 模拟了染色体结构维护 (SMC) 蛋白质复合体和拓酶对染色体组织的影响.
主要成果:
- 基本蛋白质 (SMC-scpAB和topoisomerases) 足以在theta结构内同时进行染色体分离.
- 循环挤出机制作为跨细胞类型的通用染色体组织策略得到支持.
- 分析了核糖体扩散,并生成了染色体接触图,揭示了子细胞之间的相互作用.
结论:
- 计算模型现在可以准确地代表细菌染色体在整个细胞周期中的复制和分离.
- 最小的细菌基因组具有通过循环挤出进行染色体组织和分离的固有机制.
- 开发了一种用于将聚合物染色体模型映射到粗粒度表示的方法,用于WCM验证.
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