通过与HROB复合的MCM8-9合体进行DNA解的机制
Ananya Acharya1,2, Hélène Bret3, Jen-Wei Huang4
1Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, 6500, Switzerland.
Research square
|July 18, 2023
概括
带有HROB的MCM8-9螺旋酶通过形成六合体来解DNA. HROB增强了MCM8-9螺旋酶在分支DNA结构上的活性,促进了DNA修复.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 遗传学 是一个
背景情况:
- MCM8-9螺旋酶对于同源重组至关重要,这是一个关键的DNA修复途径.
- 它的精确功能和由HROB蛋白调节的功能在很大程度上是未知的.
研究的目的:
- 为了阐明MCM8-9螺旋酶和HROB之间的相互作用.
- 要了解HROB如何调节MCM8-9的DNA解活动.
主要方法:
- 分子建模和生物化学测试来定义MCM8-9和HROB相互作用接口.
- 生物化学测试以评估DNA依赖的ATPase和Heliase活动.
- 单分子实验分析DNA解过程性和复杂形成.
主要成果:
- HROB直接接触MCM8和MCM9,增强DNA依赖的ATPase和Heliase活动.
- 在MCM8-9-HROB中,偏好地解开具有低过程性的分支DNA结构.
- MCM8-9从DNA上的二次体中形成一个六合体,由稳定和可变的接口促进,独立于HROB.
- 皮界面的ATPase位点对DNA解至关重要;HROB通过协调ATP水解促进下游解.
结论:
- HROB作为MCM8-9螺旋酶活性的调节者,特别是在复杂的DNA结构上.
- 在DNA上形成MCM8-9六合体是螺旋酶功能的先决条件,涉及不同的蛋白质-蛋白质接口.
- 在协调ATP水解和转位方面,HROB的作用对于同源重组中的高效DNA解至关重要.
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