関連する実験動画
Updated: Jan 1, 2026

11:53
Substrate Generation for Endonucleases of CRISPR/Cas Systems
Published on: September 8, 2012
27.9K
トランポゾンでコードされたCRISPR-CasシステムによるDNAターゲティングの構造的基礎
Tyler S Halpin-Healy1, Sanne E Klompe1, Samuel H Sternberg2
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA.
Nature
|December 20, 2019
まとめ
バクテリアのCRISPR-Casシステムは,DNAのトランスポーゼーションに再利用され,TniQ-カスケード複合のコラボレーションを伴う. 構造的な洞察は この複合体が DNAを標的とし 挿入を容易にし ゲノム工学の応用への道を開くことを明らかにします
科学分野:
- 微生物学
- 分子生物学
- 構造生物学
背景:
- 細菌は外来遺伝子要素に対する適応免疫のために CRISPR-Cas システムを利用する.
- タイプIのCRISPR-Casシステムは通常DNAを分解するが,核酶欠乏型の変種はTn7のようなトランポゾンによってRNA誘導トランポジションに使用される.
- CRISPRとトランポゾン機械の間の正確な協力メカニズムは以前は知られていなかった.
研究 の 目的:
- CRISPR-Cas機構とトランポゾン関連タンパク質の機能的結合の構造的基礎を解明する.
- TniQ-カスケード複合体が DNAのターゲティングと挿入をどのように媒介するかを理解する.
- プログラム可能なDNA挿入のためのこれらのシステムのエンジニアリングのための基礎を提供するために.
主な方法:
- TniQ-カスケード複合体の構造を決定するために,冷凍電子顕微鏡 (cryo-EM) が使用されました.
- 転置タンパク質TniQのデノボモデリングと精製
- 標的DNAに結合した複合体の構造分析
主要な成果:
- TniQ-カスケード複合体の構造が決定され,カスケード複合体へのダイマーとしてのTniQ結合が明らかになった.
- Cas8-Cas5融合タンパク質は,柔軟な挿入領域を通じてTniQ二重体と相互作用する.
- 標的DNA結合構造は,プロトスペーサー付近のモチーフ認識とRループ形成の鍵となる相互作用を特定した.
結論:
- この研究は,CRISPR-Casとトランスポソン装置の機能的結合のメカニズム的基礎を明らかにしています.
- この発見は,TniQ-カスケード複合体によって媒介されるDNAターゲティングと挿入の構造的な理解を提供します.
- この研究は,ゲノム工学におけるプログラム可能なDNA挿入のためのこれらのシステムを設計する努力を導くでしょう.
関連する概念動画
CRISPR
57.3K
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...
57.3K
CRISPR/Cas9 Genome Editing
1.5K
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...
1.5K
CRISPR and crRNAs
18.6K
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...
18.6K
DNA-only Transposons
17.0K
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
The donor site from where the transposon is excised is either degraded or...
17.0K
The Antiviral System of Bacteria and Archaea: CRISPR
556
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...
556
Overview of Transposition and Recombination
18.6K
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
18.6K

