Staphylococcus aureus Cas9の結晶構造について
Hiroshi Nishimasu1, Le Cong2, Winston X Yan3
1Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan; JST, PRESTO, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
Cell
|August 29, 2015
まとめ
研究者らは,Staphylococcus aureus Cas9 (SaCas9) の結晶構造を解明し,多様なDNA標的を認識するメカニズムを明らかにした. この構造的な洞察は,先進的なCRISPR-Cas9ゲノム編集ツールの開発を可能にします.
科学分野:
- 生物化学
- 分子生物学
- 構造生物学
背景:
- CRISPR-Cas9技術は Cas9のようなRNA誘導DNAエンドヌクレアスを基因編成に利用しています
- Staphylococcus aureus Cas9 (SaCas9) は,Streptococcus pyogenes Cas9 (SpCas9) に対してより小さく,より手軽に管理できる代替品であり,インビヴォの用途に使用されます.
研究 の 目的:
- ガイドRNAと標的DNAに結合するSaCas9の高解像度結晶構造を決定する.
- SaCas9 のリラクゼートされたプロトスペーサー付近モチーフ (PAM) の構造的基礎を解明する.
- PAM特異性とガイドRNA結合の違いを理解するために,SaCas9とSpCas9の構造を比較する.
主な方法:
- SaCas9-sgRNA-DNA複合体の構造を取得するために,X線結晶学を使用した.
- SaCas9とSpCas9の構造分析と比較が行われました.
主要な成果:
- SaCas9の2つの異なるDNAターゲット (5'-TTGAAT-3' PAMと5'-TTGGGT-3' PAM) の結晶構造は2. 6と2. 7 Åの解像度で決定された.
- この構造は,SaCas9が5'-NNGRRT-3'-PAM配列を緩やかに認識するメカニズムを明らかにした.
- 構造的な比較により,SaCas9とSpCas9の特徴が保存され,その異なるPAM特異性が説明されました.
結論:
- SaCas9の構造的な洞察は,そのユニークなPAM認識を理解するための基盤を提供します.
- この知識は,転写活性化剤と誘導性核酸を含む,新しいCRISPR-Cas9ベースのゲノム編集ツールの合理的な設計を容易にする.
関連する概念動画
CRISPR
59.3K
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...
59.3K
CRISPR and crRNAs
19.6K
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...
19.6K
CRISPR/Cas9 Genome Editing
2.7K
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...
2.7K
The Antiviral System of Bacteria and Archaea: CRISPR
999
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...
999
Staphylococcal Skin Infections
72
Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
72
ATP Synthase: Structure
17.7K
ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
17.7K


