定向进化扩大了CRISPR-Cas12a的基因组编辑能力
Enbo Ma1,2, Kai Chen1,2, Honglue Shi1,3
1Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, United States.
Nucleic acids research
|July 17, 2025
概括
研究人员设计了CRISPR-Cas12a (集群定期间隔的短Palindromic重复-Cas12a) 来识别新的DNA序列. 这种增强的基因组编辑工具Flex-Cas12a扩大了治疗和农业应用的准能力.
科学领域:
- 生物技术是生物技术.
- 分子生物学分子生物学
- 基因组学就是基因组学.
背景情况:
- CRISPR-Cas12a是一种强大的RNA引导的基因组编辑系统.
- 它的实用性受到一个狭窄的原始空间体相邻动机 (PAM) 识别 (5'-TTTV-3') 的限制,将向限制在基因组的1%左右.
- 扩大PAM识别对于更广泛的基因组应用至关重要.
研究的目的:
- 为了设计拉克诺斯皮拉氏菌Cas12a的变体,并扩展了PAM识别.
- 为了克服野生类型Cas12a.的准限制.
- 为了提高CRISPR-Cas12a的多功能性,用于基因组工程.
主要方法:
- 基于细菌的定向进化试验.
- 理性蛋白质工程的Cas12a.
- 生物化学和基于细胞的测试来表征变异.
- 对PAM识别特异性的分析.
主要成果:
- 识别了具有扩展PAM识别的Cas12a变体,包括非正规的动机.
- 开发了Flex-Cas12a,它除了正规的5'-TTTV-3' PAM之外还能识别5'-NYHV-3' PAM.
- 扩展DNA识别部位到大约25%的人类基因组.
- 证明保留了对正典PAM的认可.
结论:
- 工程 Cas12a 变种,特别是 Flex-Cas12a,显著扩大基因组准能力.
- Flex-Cas12a可以访问以前无法访问的基因组位置.
- 这种进步为治疗和农业基因组工程提供了新的机会.
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