通过结构比较来寻找抗CRISPR蛋白的起源
Harutyun Sahakyan1, Kira S Makarova1, Eugene V Koonin1
1National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA.
The CRISPR journal
|June 5, 2023
概括
许多病毒抗CRISPR蛋白 (Acrs) 的结构建模以了解它们的起源. 研究人员确定了潜在的祖先蛋白质,揭示了毒素-抗毒素和SOS修复系统对抗CRISPR功能的招募.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 生物信息学是一种生物信息学.
背景情况:
- 细菌和古人类病毒利用抗CRISPR蛋白 (Acrs) 来抑制CRISPR-Cas系统.
- Acrs通常是小的非酶性蛋白质,它们会干扰Cas效应蛋白.
- 由于与CRISPR-Cas系统的共同进化,Acrs的快速进化使进化分析复杂化.
研究的目的:
- 为了阐明抗CRISPR蛋白质 (Acrs) 的进化起源.
- 为了识别潜在的祖先蛋白质,这些蛋白质被重新定型为Acrs.
- 了解用于抗CRISPR功能的细胞组件的招募趋势.
主要方法:
- 使用AlphaFold2.2.使用3693 Acrs的综合结构建模.
- 将模拟的Acr结构与蛋白质数据库 (PDB) 的比较.
- 序列相似性聚类以获得102Acr家庭的高质量结构模型.
- 结构比较以识别同类并推断祖先蛋白质.
主要成果:
- 产生了363个高质量的结构模型,代表了102个不同的Acr家族.
- 通过基于结构的比较,确定了13个Acr家族的潜在祖先蛋白质.
- 观察到明显的进化趋势,包括毒素-抗毒素系统和SOS修复组件的招募.
结论:
- 结构建模提供了一种强大的方法来研究像Acrs.这样快速进化的蛋白质的起源.
- 进化分析表明,Acrs经常从现有的细胞功能中重新使用.
- 毒素-抗毒素和SOS修复系统的招募突显了反CRISPR机制进化的关键策略.
相关概念视频
CRISPR
52.5K
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...
52.5K
The Antiviral System of Bacteria and Archaea: CRISPR
62
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...
62
CRISPR/Cas9 Genome Editing
78
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...
78
CRISPR and crRNAs
17.1K
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...
17.1K
Homologous Recombination
50.7K
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...
50.7K
Conservation of Protein Domains Over Different Proteins
11.0K
Protein domains are small structurally independent units that are part of a single amino acid chain. Although these domains are often structurally independent, they may rely on synergistic effects to perform their functions as part of a larger protein. Protein domains may be conserved within the same organism, as well as across different organisms.
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to...
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to...
11.0K


