将DNA包装密度分布和TAD边界位置联系起来
Luming Meng1,2, Fu Kit Sheong3, Qiong Luo4
1Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510630, People's Republic of China.
概括
较低的DNA包装密度区域优先形成拓学关联域 (TAD) 边界. 这一发现将染色质结构与基因组调节联系起来,并解释了TAD的形成,影响了我们对基因组织的理解.
科学领域:
- 基因组学就是基因组学.
- 生物物理学的生物物理.
- 计算生物学 计算生物学
背景情况:
- DNA被组织成色素,它形成具有关键调节边界的拓关联域 (TAD).
- 了解决定TAD边界位置的因素对于基因组调节至关重要.
研究的目的:
- 调查DNA包装密度分布如何影响TAD边界位置.
- 基于聚合物物理和DNA可访问性,开发TAD形成的预测模型.
主要方法:
- 开发了一种基于聚合物物理的染色质折叠模型,使用DNA可访问性数据来定义DNA包装密度.
- 在核中模拟异质聚合物的随机折叠,以产生构造组合.
- 根据Hi-C和FISH实验数据验证的模型预测.
主要成果:
- 该模型成功地复制了FISH实验中超过60%的人类TAD边界和空间距离矩阵.
- 仅仅DNA可访问性数据就足以预测T细胞分化过程中的TAD动态.
- 较低DNA包装密度的区域被确定为域边界形成的首选地点.
- 该模型解释了CTCF对局部DNA包装密度的影响在CTCF结合部位的TAD边界的丰富.
结论:
- 建立了TAD边界和DNA包装密度较低的区域之间的强烈相关性.
- 提供了对驱动TAD形成的机制及其细胞间变异性的洞察.
- 证明了生物物理建模对于理解基因组组织和调节的实用性.
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