通过简单的核酶诱导的双链断裂进行精确的治疗基因校正
Sukanya Iyer1, Sneha Suresh1, Dongsheng Guo2,3
1Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA, USA.
Nature
|April 5, 2019
概括
这项研究引入了微复制突变的新基因校正方法. 通过创建DNA断裂, 它有效地将引起疾病的序列逆转为野生类型,
科学领域:
- 分子生物学
- 基因编辑
- 遗传性疾病
背景情况:
- 像CRISPR-Cas9这样的当前基因校正方法依赖于同质导向的修复,需要外源DNA捐赠者,并且在许多细胞类型中表现出效率低下.
- 微复制可以导致与疾病相关的框架转移突变,这对精确的基因纠正构成挑战.
研究的目的:
- 开发一种更有效,更简单的方法来纠正引起疾病的微复制突变.
- 在患者衍生细胞系中证明一种新的基因校正策略的有效性.
主要方法:
- 使用可编程核酶 (SpCas9和LbCas12a) 在微复制中心附近产生DNA双链断裂.
- 使用微同质介导端连接 (MMEJ) 途径进行精确的序列逆转.
- 在患者衍生细胞系中测试该策略,以检测2G型肢体腰带肌肉衰竭 (LGMD2G) 和1型赫曼斯基-普德拉克综合征 (HPS1).
主要成果:
- 在LGMD2G和HPS1患者细胞系中有效地逆转致病的框架转移突变为野生类型序列.
- 大约80%的LGMD2G iPS细胞含有至少一种野生类型的TCAP等位基因,可恢复基因表达.
- 抑制PARP-1抑制了校正,证实了MMEJ途径的参与.
结论:
- 一个基于核酶的新策略通过MMEJ途径有效地纠正微复制突变.
- 这种方法广泛适用于各种微复制长度和核酶,提供了更简单,更可靠的基因校正疗法.
- 基于MMEJ的战略有望开发用于微复制相关疾病的新基因校正疗法.
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