構造生物学について. 標的DNAの認識のために前編成されたCas9ガイドRNA複合体
Fuguo Jiang1, Kaihong Zhou2, Linlin Ma2
1Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|June 27, 2015
まとめ
バクテリアのCRISPR-Cas9システムは,ガイドRNAのシード配列を使用して,DNAターゲティングのためのCas9酵素を事前にオーダーします. このメカニズムは,細菌の適応免疫に不可欠であり,真核性RNAの干渉経路に似ています.
科学分野:
- 分子生物学は分子生物学である.
- 微生物学 微生物学とは
- 遺伝学 遺伝学とは
背景:
- バクテリアの適応免疫は,外来DNAを分解するためにCRISPR-Casシステムに依存しています.
- Cas9エンドヌクレアゼを含むII型CRISPR-Casシステムは,不明なメカニズムを通じてガイドRNA結合を通じてDNA認識のために活性化されます.
研究 の 目的:
- ガイドRNA結合時にCas9の活性化の構造的メカニズムを解明する.
- ガイドRNAのシード配列がCas9の構成とDNAの結合にどのように影響するかを理解する.
主な方法:
- シングルガイドRNAに結合したCas9の結晶構造を決定した.
- Cas9の形状をアポ,ガイドRNA結合,DNA結合状態で分析した.
主要な成果:
- シングルガイドRNAに結合するCas9は,アポとDNAに結合した状態とは異なるユニークな形状を採用しています.
- 10ヌクレオチドガイドRNAシード配列は,DNA尋問のために事前にオーダーされたA型コンフォームを採用しています.
- この事前オーダーされたシード配列は,DNA認識に適したCas9構造の形成に不可欠です.
結論:
- ガイドRNAシード配列は,標的DNA認識のためのCas9のプライミングにおいて重要な役割を果たします.
- バクテリアのCRISPR-Cas9におけるこの"種子"メカニズムは,RNAの干渉において,真核アルゴナウトのタンパク質との収束進化を示している.
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