基因组和基因组变异家族在核细胞中
Samuel Schwab1,2,3, Yimin Hu4, Bert van Erp1,2,3
1Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands.
Nature communications
|September 11, 2024
概括
新的计算方法揭示了古生物和细菌中的新型组素家族. 一些基因组与DNA形成桥梁,而不是包裹它,扩大了我们对染色质组织的理解.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 基因组学就是基因组学.
背景情况:
- 基因组对于真核生物和古生物的DNA组织至关重要,形成核体.
- 在一些细菌和古生物中存在具有不同序列和DNA结合性质的替代性质子.
- 在元基因组中发现了许多新型组织蛋白,阻碍了体内研究.
研究的目的:
- 用先进的计算蛋白质结构预测来对 prokaryotic 基因组多样性进行分类.
- 为了识别和表征新型的基因素超级家族和家族.
- 为了理解原生细胞基因组与正规核细胞基因组的功能差异.
主要方法:
- 利用AlphaFold2和RoseTTAfold进行大规模的计算蛋白质结构预测.
- 将预测的细胞原生组织组织结构分类为17个不同的组.
- 分析了序列和结构数据,以识别新型的基因素超级家族和家族.
主要成果:
- 鉴定出一种超级家族的"α3基因组",在古生物中普遍存在,并且存在于一些细菌中.
- 发现了一大家族的古生物学和细菌组织蛋白,这些组织蛋白与DNA形成桥梁,而不是包裹它.
- 与传统的核细胞组组组织蛋白相比,确立了显著的结构和功能差异.
结论:
- 计算结构预测为未表征的蛋白质家族提供了强大的洞察力.
- Prokaryotic 基因组的多样性比以前估计的要大,具有新的 DNA 结合机制.
- 发现DNA桥接质子挑战了传统的染色体组织模型.
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