来自未培养的微生物的新型和工程类型IICRISPR系统具有广泛的基因组编辑能力
Lisa M Alexander1, Daniela S Aliaga Goltsman1, Jason Liu1
1Metagenomi, Inc., Discovery, Emeryville, California, USA.
The CRISPR journal
|June 5, 2023
概括
研究人员从微生物基因组中发现了数千种新的CRISPR-Cas9系统. 这些新型核酶提供了增强的向性,减少非向性效应和更小的尺寸,扩大了生物技术和治疗领域的潜在应用.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 生物技术是生物技术.
背景情况:
- 第二种类型的集群定期间隔的短时间Palindromic重复 (CRISPR) -Cas9核酶是生物技术和治疗中的重要工具.
- 目前的CRISPR-Cas9系统面临大小,可定位性和非定位效应的限制,阻碍了更广泛的应用.
研究的目的:
- 发现具有改进特性的新型II型CRISPR-Cas9效应器.
- 扩大CRISPR-Cas9系统的定位能力,减少非定位效应.
主要方法:
- 挖掘一个大型的基因组解析的元基因组学数据库,以识别CRISPR II型因子.
- 开发一个高通量管道来预测tracrRNA,设计单一导向RNA,并证明体外核酶活性.
- 工程 PAM 交互域以提高可定位性.
主要成果:
- 识别了成千上万的CRISPR II型效应因子,包括41个新描述的子组,证明了体外活性.
- 发现了具有多种蛋白序列的核酶,指导RNA结构和多种原空间邻基因 (PAM) 的发现.
- 几种新型核酶表现出与SpCas9相比或超过的高活性,在哺乳动物细胞中具有较小的大小和较低的非目标编辑.
结论:
- 新发现的CRISPR核酶与现有系统相比,具有显著的优势,包括增强活动,更小的尺寸和更好的特异性.
- 工程化马进一步扩大了这些新型核酶的准范围.
- 这些发现展示了CRISPR酶的多样化工具包,具有相当大的转化到各种应用的潜力,特别是在治疗中.
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