RNAとDNAを結合するヘリックス・ターン・ヘリックスタンパク質によるファグの抗CRISPR制御
Nils Birkholz1,2,3,4, Kotaro Kamata1,2, Maximilian Feussner5
1Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand.
Nature
|July 10, 2024
まとめ
新しい調節タンパク質であるAca2は,そのヘリックス・ターン・ヘリックス・ドメインを使用して,DNAとRNAの両方の結合によってファグの抗CRISPR遺伝子発現を制御し,感染中に毒性の過剰発現を防ぐ.
科学分野:
- 分子生物学
- 遺伝学
- 微生物学
背景:
- 遺伝子発現の調節は 細胞の機能に不可欠です
- ヘリックス・ターン・ヘリックス (HTH) ドメインタンパク質は重要な調節因子である.
- バクテリオファージは抗CRISPR (acr) 遺伝子を用いて細菌の防御を回避し,HTHタンパク質 (Aca) がその発現を抑制する.
研究 の 目的:
- HTH 調節体がファグ感染時に抗CRISPR 産生をどのように管理するのかを調査する.
- Aca2がacr遺伝子発現を制御するメカニズムを決定する.
- HTHドメインの二重DNAとRNA結合能力を理解する.
主な方法:
- アカ2RNA複合体を視覚化するための冷凍電子顕微鏡
- DNAとRNAの結合を研究する生化学的測定法
- Aca2タンパク質ファミリーの規制メカニズムの分析.
主要な成果:
- Aca2は,DNA結合によって,反CRISPR合成を抑制する.
- Aca2はまた,RNA幹のループを結合し,リボソームへのアクセスを阻害することでmRNA翻訳を阻害する.
- Cryo-EM構造は,Aca2のHTHドメインがDNAとRNAの結合部位を区別することを示しています.
結論:
- Aca2は,抗CRISPR遺伝子発現の正確な制御のために,二重の調節メカニズム (DNAとRNA結合) を採用しています.
- この二重調節は,有害な過剰発現なしに,迅速なファグ複製中に効果的なCRISPR- Cas抑制を可能にします.
- HTHドメインは,多くのタンパク質ファミリーにわたる二重DNA/RNA結合の可能性を持つ多用途のレギュレータである.
関連する概念動画
CRISPR and crRNAs
16.9K
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...
16.9K
CRISPR
50.4K
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...
50.4K
RNA Interference
26.0K
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
26.0K
Experimental RNAi
6.1K
RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
6.1K
Types of RNA
63.5K
Overview
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
63.5K
Conservative 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


