通过通过独特的四重化接口,通过一个古老的质子变体进行DNA桥接
Sapir Ofer1, Fabian Blombach1, Amanda M Erkelens2
1Institute for Structural and Molecular Biology, Division of Biosciences, University College London, Darwin Building, Gower Street, London, WC1E 6BT, UK.
Communications biology
|September 22, 2023
概括
考古基因组素MJ1647形成了桥梁DNA的四重体,与真核基因组素不同. 这种独特的DNA桥梁能力影响了古人类的基因组结构和基因调节.
科学领域:
- 结构生物学是结构生物学.
- 分子生物学分子生物学
- 基因组学就是基因组学.
背景情况:
- 单核细胞中的质子形成异构体 (H3/H4,H2A/H2B) 形成核体.
- 考古基因组是二元的,与DNA一起形成"超核体".
- 考古历史基因素变体的功能仍然在很大程度上是未知的.
研究的目的:
- 描述从Methanocaldococcus jannaschii.MJ1647中发现的古老基斯类似物MJ1647的结构和功能.
- 调查其独特的C端扩展的作用.
- 了解它对古人类基因组结构和基因表达的影响.
主要方法:
- 用X射线晶体 (1.9 Å分辨率) 来确定二维的MJ1647结构.
- 结构建模用于预测四聚体形成.
- 位点定向突变发生,以分析功能域.
- 单分子绑定粒子运动测定.
- DNA 结合测试.DNA 结合测试.
主要成果:
- MJ1647具有独特的C端延伸,使其能够进行同位四极化.
- 四重化模块涉及两个阿尔法螺旋在握手安排.
- MJ1647四基体表现出DNA桥接能力,不同于正规基因组体.
- 四聚胺约约60bp的DNA和合作紧的DNA结合.
- 在体外,MJ1647抑制了转录机器对促进体的访问.
结论:
- MJ1647是第一个具有DNA桥梁性质的已识别的基因素.
- 这些特性表明它在古人类基因组组织中起着重要作用.
- MJ1647的功能对调节古生物中的基因表达有影响.
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