関連する実験動画
Updated: Jan 16, 2026

11:53
Substrate Generation for Endonucleases of CRISPR/Cas Systems
Published on: September 8, 2012
28.0K
機能的なRNA分裂は,トランポゾンからタイプVのCRISPR-Casシステムの進化的出現を促した
Shuai Jin1, Zixu Zhu2, Yunjia Li2
1New Cornerstone Science Laboratory, Center for Genome Editing, Laboratory of Advanced Breeding Technologies, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
Cell
|September 30, 2025
まとめ
トランポゾンでコードされたTnpB核酸はCRISPR-Casシステムに進化した. 研究者らは,分割されたRNAガイドを使用するトランポゾン-CRISPR中間体 (TranCs) を発見し,トランポゾンがCRISPR免疫をどのように生み出したかを明らかにした.
科学分野:
- 分子生物学
- 遺伝学
- 微生物学
背景:
- トランポゾンでコードされたTnpB核酸は,タイプVのCRISPR- Cas12エフェクタの祖先である.
- TnpBシステムはトランポゾン由来RNA (reRNA) を使用し,CRISPRシステムはCRISPRRNA (crRNA) をDNA標的化に使用する.
- トランポゾン活性とCRISPR免疫の進化的関連は完全に理解されていません.
研究 の 目的:
- トランポゾン活動とCRISPR免疫を結びつける 分子機構を調査する.
- トランポゾンからCRISPR-Casシステムの進化における中間分子プレーヤーを特定する.
主な方法:
- トランポゾン-CRISPR中間体 (TranCs) の識別と特徴付け
- クリオ電子顕微鏡 (cryo-EM) を用いた構造分析.
- エンジニアリングされたRNA成分を含む機能的アッセイ
主要な成果:
- IS605/IS607-TnpB系統の TranCsは,crRNAsとreRNAsの両方をDNA分裂に使用して識別されました.
- LaTranCの冷凍-EM構造は,ISDra2 TnpBに類似しているが,機能的に分割されたガイドRNA (tracrRNAとcrRNA) を有している.
- ISDra2 TnpBでのRNA分裂はCRISPR配列で活性化されました.
結論:
- 機能性RNA分裂は,トランポゾンから多様なV型CRISPR-Casシステムの進化における重要な分子イベントである.
- TranCsは,この進化的移行の 中間を代表しています.
- この研究は,トランポゾンベースの核酸が適応性免疫システムに適応する過程を明らかにしています.
関連する概念動画
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
CRISPR
57.5K
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...
57.5K
The Antiviral System of Bacteria and Archaea: CRISPR
623
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...
623
piRNA - Piwi-interacting RNAs
7.5K
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
7.5K
LTR Retrotransposons
19.4K
LTR retrotransposons are class I transposable elements with long terminal repeats flanking an internal coding region. These elements are less abundant in mammals compared to other class I transposable elements. About 8 percent of human genomic DNA comprises LTR retrotransposons. Some of the common examples of LTR retrotransposons are Ty elements in yeast and Copia elements in Drosophila.
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
The internal coding region of LTR retrotransposons and their mechanism of transposition closely resembles a...
19.4K
Bacterial RNA Polymerase
32.5K
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
32.5K

