相关实验视频
Updated: Jul 14, 2025

08:23
CIRCLE-Seq for Interrogation of Off-Target Gene Editing
Published on: November 1, 2024
675
负DNA超引发全基因组的Cas9目标外活动
Matthew D Newton1, Marialucrezia Losito2, Quentin M Smith3
1Department of Infectious Disease, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0HS, UK; Single Molecule Imaging, MRC-London Institute of Medical Sciences, Du Cane Road, London W12 0HS, UK; DSB Repair Metabolism Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
Molecular cell
|October 6, 2023
概括
像负超卷一样,DNA拓学显著增加了CRISPR-Cas9基因编辑的目标外活动. 这一发现揭示了细胞过程如何无意中产生意外的DNA断裂,影响治疗安全.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物技术是生物技术.
背景情况:
- 克里斯普尔-Cas9基因编辑具有治疗潜力,但面临着非目标活动的挑战.
- 之前的研究表明,DNA拉伸会产生异常效应.
- 假设:DNA的拓扭曲,例如负超卷,可能会降低Cas9的特异性.
研究的目的:
- 为了研究DNA拓学的影响,特别是负超,对CRISPR-Cas9的特异性.
- 为了确定DNA扭曲是否在体外和体内影响Cas9的目标外结合和裂变.
主要方法:
- 单分子光学笔用于研究DNA超级卷对Cas9结合的影响.
- 适应的CIRCLE-seq用于检测全基因组的非目标双链断裂.
- 在体内实验中评估了局部定向DNA扭曲对细胞目标外活动的影响.
主要成果:
- 负超的DNA诱导了特定序列的Cas9在多个位点的脱结合,即使在低强度下也是如此.
- 在全基因组中检测到超过10,000个Cas9非目标双链断裂,这归因于在超级卷轴下增加的不匹配耐受性.
- 细胞中的局部定向DNA扭曲增加了CRISPR-Cas9的目标外活动,在基因组编辑过程中可以检测到事件.
结论:
- 克里斯普尔-卡斯9的目标外活性在体外和体内都受到DNA拓学的显著调节.
- 涉及DNA拓变化的细胞过程,如转录和复制,可能会导致在新网站的目标活动.
- 了解DNA拓学的作用对于提高CRISPR-Cas9的特异性和治疗安全性至关重要.
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