在I-C型CRISPR-Cas3中利用激活和非激活机制,用于基因组编辑应用
Chunyi Hu1, Mason T Myers2, Xufei Zhou2
1Department of Molecular Biology and Genetics, Cornell University, 253 Biotechnology Building, Ithaca, NY 14853, USA; Department of Biological Sciences, Faculty of Science; Department of Biochemistry, Precision Medicine Translational Research Programme (TRP), Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore.
Molecular cell
|January 19, 2024
概括
I-C型CRISPR-Cas系统精确地针对大基因组删除的DNA. 新的抗CRISPR蛋白,AcrIC8和AcrIC9,可以控制真核生物的基因组工程.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 结构生物学 结构生物学
背景情况:
- I型CRISPR-Cas系统是细菌和古生物体的适应性免疫机制.
- 类型I-C亚型以其紧的结构和在人类细胞中产生大型基因组删除的效率而闻名.
- 了解DNA向和分裂的精确机制对于利用CRISPR技术至关重要.
研究的目的:
- 阐明类型I-C CRISPR-Cas系统的高分辨率RNA引导的DNA结合和分裂机制.
- 为了识别和描述抑制I-C型活性的新型抗CRISPR蛋白质.
- 在真核生物系统中提供控制I型CRISPR介导基因组编辑的工具.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 捕捉了四个不同的结构快照.
- 生物化学测试被用来分析DNA结合和裂变.
- 进行了结构分析,以了解抗CRISPR蛋白的抑制机制.
主要成果:
- 高分辨率结构揭示了IC级联如何适应非目标DNA链,以及Cas3结合如何促进DNA断.
- 在Neisseria lactamica中发现了两种新的抗CRISPR蛋白,AcrIC8和AcrIC9.
- AcrIC8通过全性抑制PAM识别来抑制I-C类型,而AcrIC9直接与DNA结合竞争.
- 无论是AcrIC8还是AcrIC9,都有效地抑制了人类细胞中的I型C介导的基因组编辑和转录调制.
结论:
- 这项研究为I-C型CRISPR-Cas系统的DNA结合和分裂机制提供了前所未有的结构洞察力.
- AcrIC8和AcrIC9代表了第一个特征化的抗CRISPR蛋白质,它们专门抑制了I-C型功能.
- 这些发现为精确控制和调节基于CRISPR的类型I基因组工程在真核生物中提供了有价值的工具.
相关概念视频
02:53CRISPR and crRNAs
17.0K
Bacteria and archaea are susceptible to viral infections just like eukaryotes; therefore, they have developed a unique adaptive immune system to protect themselves. Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins (CRISPR-Cas) are present in more than 45% of known bacteria and 90% of known archaea.
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
17.0K
01:59CRISPR
51.1K
Genome editing technologies allow scientists to modify an organism’s DNA via the addition, removal, or rearrangement of genetic material at specific genomic locations. These types of techniques could potentially be used to cure genetic disorders such as hemophilia and sickle cell anemia. One popular and widely used DNA-editing research tool that could lead to safe and effective cures for genetic disorders is the CRISPR-Cas9 system. CRISPR-Cas9 stands for Clustered Regularly Interspaced...
51.1K
02:31Homologous Recombination
50.6K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
50.6K
02:53Conservative Site-specific Recombination and Phase Variation
6.0K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.0K