对Cas9特异性的差异性Allosteric调制
Yuanhao Li1, Xin Li1, Yingjie Chen1
1College of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
Journal of chemical theory and computation
|January 9, 2026
概括
通过改变导向RNA (gRNA) 或Cas9.9来提高CRISPR-Cas9基因编辑精度. 这些变化虽然远离活性部位,但通过固定HNH核酶域来控制Cas9,从而增强编辑特异性.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
- 基因组学就是基因组学.
背景情况:
- 克里斯普尔-Cas9基因编辑依赖于精确的准,但偏离目标的切割仍然是一个挑战.
- 修改导向RNA (gRNA) 和Cas9变体等策略旨在提高特异性.
- 远程修饰如何影响Cas9活性的基础分子机制尚未完全理解.
研究的目的:
- 阐明PAM远端变化调节CRISPR-Cas9活性和特异性的分子机制.
- 调查gRNA截断,基不匹配和Cas9突变如何影响Cas9的结构动力学和全调节.
- 建立一个动态框架,将远程结构干扰与Cas9活动控制联系起来.
主要方法:
- 使用了近毫秒的全原子分子动力学模拟.
- 模拟分析了各种PAM远程扰动对Cas9的影响.
- 研究了Cas9的形态动态和性调节.
主要成果:
- 所有测试的扰动,包括gRNA截断和基不匹配,通过改变HNH动态来阻碍过渡到催化活性状态.
- 对于不同的干扰,确定了不同的全路径,包括REC3重定位和L2链接器参与.
- 发现进化的突变重塑了全球运动模式,限制了HNH的灵活性.
结论:
- 多个结构途径汇聚在HNH固定和催化抑制上,统一了RNA,DNA和蛋白质修饰的影响.
- 这项研究提供了对Cas9忠诚度调节的机制性见解.
- 这些发现为设计下一代高精度基因组编辑器提供了原则.
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