在指导RNA结合时的结构转换及其在Cas12g介导RNA裂变中的重要性
Mengxi Liu1, Zekai Li1, Jing Chen1
1Key Laboratory of Microbial Pathogenesis and Interventions-Fujian Province University, the Key Laboratory of Innate Immune Biology of Fujian Province, Biomedical Research Center of South China, Key Laboratory of OptoElectronic Science and Technology for Medicine of the Ministry of Education, College of Life Sciences, Fujian Normal University, Fuzhou, China.
PLoS genetics
|September 20, 2023
概括
Cas12g是一种CRISPR-Cas酶,在结合单导向RNA (sgRNA) 时经历了显著的结构变化. 这些形状变化,包括手指和盖子图案的转换,对于其RNA分裂活动和RNA编辑中的潜在用途至关重要.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- Cas12g是一种V型RNA导向的CRISPR-Cas内核酶.
- 它具有由其RuvC域介导的RNA分裂活性.
研究的目的:
- 阐明Cas12g在其apo和sgRNA结合状态中的结构机制.
- 为了研究与sgRNA结合和激活相关的构造变化.
- 为重新利用Cas12g用于RNA编辑应用奠定了基础.
主要方法:
- 对Apo-Cas12g的晶体结构的确定.
- 用冷电子显微镜 (cryo-EM) 确定Cas12g-sgRNA二进制复合物的结构.
- 对RNA裂变的构造变化和突变影响的分析.
主要成果:
- 该研究确定了apo-Cas12g和Cas12g-sgRNA复合物的结构.
- 指纹图案在sgRNA结合时从有序转变为无序,影响裂变.
- 在RuvC域中的一个盖面图案从螺旋转变为循环,调节RNase活动.
结论:
- 在sgRNA结合时,Cas12g经历了关键的形状变化,涉及指和RuvC盖面图案.
- 这些结构动态对于sgRNA识别和RNA基质分裂至关重要.
- 这些发现支持Cas12g作为RNA编辑技术的新工具的潜力.
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