电荷分布和DNA之间的相互作用在塑造HP1对应相分离和定位方面的作用
Tien M Phan1, Young C Kim2, Galia T Debelouchina3
1Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX, USA.
bioRxiv : the preprint server for biology
|July 3, 2023
概括
这项研究揭示了蛋白质序列中的净电荷和电荷模式决定了异性染色蛋白1 (HP1) 对应物如何相互作用. DNA 结合也会影响 HP1 的对应物相互作用和凝结物的稳定性.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 计算生物学 计算生物学
背景情况:
- 异染色蛋白1 (HP1) 家族对于异染色蛋白的形成和功能至关重要.
- 人类细胞具有三个HP1对应物 (HP1α,HP1β,HP1γ) 具有相似的结构,但具有不同的液态-液态相分离 (LLPS) 行为.
研究的目的:
- 为了识别控制 HP1 对应器差异 LLPS 的序列特征.
- 为了研究DNA在HP1对应物相互作用和凝结物形成中的作用.
主要方法:
- 使用粗粒度模拟来建模HP1的paralog行为.
- 分析的重点是序列属性,如净电荷和电荷模式.
- 模拟探索了共同定位和DNA相互作用.
主要成果:
- 蛋白质序列的净电荷和电荷分布是HP1平行LLPS的关键决定因素.
- 保存的折叠域和保存较少的无序区域都会导致差异性的LLPS.
- 通过竞争性相互作用,DNA结合显著改变了HP1对应物凝聚物的稳定性.
结论:
- HP1对应序列的物理化学特性驱动它们独特的相位分离行为.
- 了解这些相互作用为HP1在染色质组织中的作用提供了分子基础.
- DNA 作为HP1介导的染色质凝聚物的显著调节器.
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