トランポゾン媒介のサイト固有の再結合 in vitro: 再結合部位におけるDNA分裂とタンパク質-DNA結合

R R Reed, N D Grindley

Cell

|September 1, 1981

まとめ

リゾルバゼ酵素は,リゾルバゼ部位でDNAを分裂させ,部位特異のDNA再結合を媒介する. この酵素はDNAの末端に共性的に結合し,ガンマデルタトランスポーザブル要素の再結合を促進します.

科学分野:

分子生物学は分子生物学である.
遺伝学遺伝学とは
バイオケミストリーバイオケミストリー

背景:

リゾルバゼ (Resolvase) は,ガンマデルタトランスポーザブル要素のtnpR遺伝子によってコードされたタンパク質です.
それは,レプリコン上の要素の直接繰り返されたコピーの間のサイト固有の再組み合わせを容易にする.
解析部位 (res) は,tnpAとtnpR遺伝子の間に位置しています.

研究の目的:

リゾルバゼによって媒介されるサイト固有の再結合のインビトロメカニズムを研究する.
リゾルバゼ-DNA複合体の形成と再結合におけるDNA分裂の役割を明らかにする.

主な方法:

リゾルバゼ媒介による再結合のインビトロ研究.
Mg2+がない場合の溶解酵素複合体の形成の分析.
DNA分裂産物と溶解酵素-DNA相互作用の特徴化.

主要な成果:

リゾルバゼ-レス複合体は,リゾルバゼ部位で割れたDNAを含む,インビトロで形成される.
リゾルバゼは,割れたDNAの5'端に共振的に結合し,自由3'ヒドロキシル群を露出する.
DNA分裂は2つのresサイトの相互作用によって刺激され,3'拡張を生成するパリンドローム配列を含む.

結論:

溶解酵素結合とDNA分裂は,ガンマデルタ元素再結合における重要な中間段階である.
酵素がDNAの末端に共性結合することで,解離過程が容易になります.
このメカニズムを理解すると,転載可能な要素の動態の規制の洞察が得られます.

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