相关实验视频
Updated: Jan 11, 2026

11:53
Substrate Generation for Endonucleases of CRISPR/Cas Systems
Published on: September 8, 2012
27.9K
在3型B CRISPR-Cas效应器和效应器组件组件期间的中间crRNA处理过程中,Archaeoglobus fulgidus的冷-EM结构
Kazuki Ishihara1, Sumire Kitagawa1, Naruhiko Adachi2
1Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, 819-0395, Japan.
Biochemical and biophysical research communications
|November 16, 2025
概括
这项研究揭示了关键的CRISPR-Cas型III-B效应复合物的结构,并揭示了crRNA成熟的新途径,扩大了我们对这些抗病毒系统的理解.
科学领域:
- 分子生物学分子生物学
- 微生物学 微生物学
- 结构生物学 结构生物学
背景情况:
- 第三种CRISPR-Cas系统对于 prokaryotes的适应性免疫至关重要,通过crRNA引导的识别准外来核酸.
- 对III-B型因子的精确分子结构和crRNA成熟途径的理解尚不完全.
- 虽然已知多核酸酶 (PNPase) 能够处理crRNAs,但人们怀疑其他成熟机制.
研究的目的:
- 为了阐明Archaeoglobus fulgidus Cmr (AfCmr) 缺少Cmr1 (AfCmrΔ1) 的效应复合物的结构.
- 在III-B型CRISPR-Cas系统中研究crRNA成熟的机制.
- 探索使跨物种组合和CMR复合物的活性成为可能的相互作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于以3.4 Å分辨率确定AfCmrΔ1-目标模拟复合物的结构.
- 进行比较界面分析以了解跨物种组件兼容性.
- 生物化学测定用于调查crRNA处理和AfCmr1.1的突变分析.
主要成果:
- 冷-EM结构揭示了一个连续的基本通道,容纳了crRNA-target异重复.
- 接口分析发现了保持灵活性,使跨物种的CMR复合组合成为可能.
- 通过AfCmrΔ1和AfCmr1证明了一种新的,离子独立的途径,用于AfCmrΔ1和AfCmr1对中间crRNA的合作性,特定站点的处理.
- 确定了AfCmr1中的关键残留物,这些残留物对这种替代crRNA成熟至关重要.
结论:
- 这些发现展示了III-B型CRISPR-Cas效应器复合体的结构,为目标识别提供了洞察力.
- 发现了一种替代的crRNA成熟路径,补充PNPase活性,扩展了CRISPR-Cas系统的已知机制.
- 这项工作增强了对CRISPR-Cas类型III抗病毒防御机制的理解.
相关概念视频
CRISPR and crRNAs
18.7K
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...
18.7K
The Antiviral System of Bacteria and Archaea: CRISPR
606
CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats is a adaptive immune system found in bacteria and archaea that protects against viral infections. This system enables prokaryotic cells to identify, remember, and neutralize foreign genetic elements, primarily bacteriophages, by storing fragments of the invader’s DNA as a genetic memory.The CRISPR immune response begins during an initial infection. Cas (CRISPR-associated) proteins play a central role in this...
606
CRISPR
57.4K
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...
57.4K
Diversity of Archaea III
311
Crenarchaeota, a prominent phylum of Archaea, is remarkable for its ability to thrive in extreme environments characterized by high temperatures and acidity. These microorganisms inhabit sulfuric hot springs, volcanic systems, and submarine hydrothermal vents, where temperatures often exceed 100°C. The unique adaptations of Crenarchaeota not only allow survival under such extreme conditions but also provide insights into the mechanisms of life in primordial Earth-like...
311
CRISPR/Cas9 Genome Editing
1.6K
The CRISPR-Cas system serves as a bacterial defense mechanism against invading genetic elements such as viruses and plasmids, forming the foundation for its adaptation as a powerful genome-editing tool. Originally discovered in prokaryotes, this system has been repurposed to revolutionize genetic engineering across a wide range of organisms, including plants, animals, and humans. The core component, Cas9, is an endonuclease derived from Streptococcus pyogenes, capable of introducing...
1.6K
Viruses of Archaea
436
Archaeal viruses play a crucial role in the ecosystems of extremophilic archaea, particularly those belonging to the phyla Euryarchaeota and Crenarchaeota. By shaping host evolution and facilitating gene transfer, these viruses influence microbial communities and contribute to genetic diversity in extreme environments. The archaea they infect thrive in acidic hot springs and hydrothermal vents characterized by high temperatures and low pH. Archaeal viruses exhibit remarkable structural...
436

