导向RNA分类使得Tn7-CRISPR-Cas转位子中的目标位置可以选择
Michael T Petassi1, Shan-Chi Hsieh1, Joseph E Peters1
1Department of Microbiology, Cornell University, Ithaca, NY 14853, USA.
Cell
|December 3, 2020
概括
在Tn7类元素中的CRISPR-Cas系统使用专门的导向RNA进行转换. 这允许针对移动等离子体和染色体位点,使有效的基因转移和宿主殖民成为可能.
科学领域:
- 分子生物学
- 微生物遗传学
- 基因组学
背景情况:
- 克里斯普尔-卡斯系统是 prokaryotes 的适应性免疫机制.
- 类似Tn7的转子利用CRISPR-Cas进行向的DNA整合.
- 原型Tn7使用不同的染色体和等离子体向途径.
研究的目的:
- 研究Tn7-CRISPR-Cas元素中的指导RNA (gRNA) 分类机制.
- 了解这些系统如何实现双重目标策略.
- 探索工程增强CRISPR-Cas功能的潜力.
主要方法:
- 对gRNA结构和识别序列进行比较分析.
- 功能性测试以评估转化效率和目标特异性.
- 对gRNA获取和调节的生物信息分析.
主要成果:
- Tn7-CRISPR-Cas元素形成了一个复杂的gRNA分类系统.
- 不同的gRNA介导转移到等离子体和染色体附着部位.
- 机制包括序列专业化,不匹配耐受性和规范识别以防止自我定位.
结论:
- Tn7-CRISPR-Cas的双重向生活方式依赖于功能专用和私有化的gRNA.
- 这一系统提供了关于转化和CRISPR-Cas合作的见解.
- 工程化gRNA可以增强基因组编辑应用的CRISPR-Cas工具.
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