ゲートメカニズムによる結合環へのDNAの入出

Yasuto Murayama¹, Frank Uhlmann¹

¹The Francis Crick Institute, Lincoln's Inn Fields Laboratory, London WC2A 3LY, UK.

Cell

|December 22, 2015

まとめ

染色体構造維持 (SMC) 複合体は,DNAを結合して放出する相互接続ゲートメカニズムを使用します. このメカニズムは,DNAセンシングライシンとWaplサブユニットを含む.

科学分野:

分子生物学
生物化学
遺伝学

背景:

染色体の構造維持 (SMC) 複合体は,DNA管理に関与する重要なタンパク質環である.
コヘシンを含むこれらの複合体は,染色体機能において重要な役割を果たします.
ダイナミックなDNA結合を理解することはゲノムの安定性を理解する鍵です

研究の目的:

分裂酵母コヘシンによるDNA捕獲と放出のメカニズムを解明する.
DNAセンシングライシン,ATP水解,およびWaplサブユニットのコヘシン機能における役割を調査する.
SMC タンパク質ファミリー全体でダイナミックな DNA 結合モデルを提案する.

主な方法:

分裂酵母凝固の生化学分析
タンパク質の相互作用と形状の変化を調査する.
特定のサブユニットと改変がDNA結合に与える影響を評価する.

主要な成果:

SMCヘッドを開くためのATP水解を誘発するDNA感知ライシンを含むメカニズムが特定されました.
ワップルのサブユニットは,ATPが再結合した後にクレイシンを解除し,相互接続ゲートを示唆します.
コヘシンロード機は,DNAセンサーを暴露するためにコヘシンを折りたたむことでDNAの侵入を容易にします.
コヘシンをリシンアセチル化することで,姉妹染色体結合が持続することが示された.

結論:

ダイナミックなDNA結合と放出のためのゲートメカニズムを使用します.
このメカニズムは,SMCタンパク質ファミリー全体で保存されます.
この発見は,ライシンアセチル化が姉妹染色体結合をどのように調節するかを説明する.

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