水溶性エンド核溶性リボ酵素 (HYER) は,配列特異のDNA分裂のためにプログラム可能である

Zi-Xian Liu¹, Shouyue Zhang¹, Han-Zhou Zhu¹

¹Beijing Advanced Innovation Center for Structural Biology, State Key Laboratory of Membrane Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.

Science (New York, N.Y.)

|February 1, 2024

まとめ

研究者達はDNAを切断できる触媒性RNAの一種である HYER を発見しましたこれらの天然のリボ酵素は精密なDNA操作とゲノム編集の応用の可能性を示しています

科学分野:

分子生物学
生物化学
遺伝学

背景:

リボ酵素は,細胞プロセスにおいて重要な役割を果たす触媒RNA分子である.
天然のリボ酵素は,DNA操作を含むRNA触媒を超えた可能性がますます認識されています.

研究の目的:

配列特異的なDNAエンドヌクレアゼとして機能する自然リボ酵素を特定し,特徴づけること.
新しいDNA操作ツールとしてリボ酵素の再利用を探求するためです

主な方法:

細菌II-C群のイントロンを中心に,研究者はイントロンにコードされたタンパク質が欠けているシステムをスクリーニングしました.
様々な核酸基板に対する識別されたリボ酵素 (HYERs) の分裂活性をテストするために,in vitroアッセイが使用された.
HYER1のDNA結合と触媒機構の構造的基礎を決定するために,冷凍電子顕微鏡を用いた.
合理的な設計戦略を適用し,特異性と機能性の向上したHYERのバリエーションを設計しました.

主要な成果:

HYER (Hydrolytic Endonucleolytic Ribozymes) と呼ばれるいくつかのイントロン系が,RNA,単鎖DNA,および双鎖DNA (dsDNA) を分割するものであることが確認された.
HYER1は,哺乳類のゲノムでdsDNAの断絶を誘導する能力をインビトロで示した.
クリオ電子顕微鏡では,Mg2+依存の水解ポケットとDNA結合能力を持つHYER1のホモジメ構造を明らかにした.
エンジニアリングされたHYERの変種は DNA操作の特異性と柔軟性を向上させました

結論:

自然のリボ酵素,特にII-C群のHYERは,DNAエンドヌクレアース活性を持っています.
これらのHYERは精密なDNA分裂のために設計され,ゲノム編集とバイオテクノロジーの有望な新しいプラットフォームを提供します.

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