カット・アンド・ペーストトランスポジション中のRAGのようなトランスポゼの構造
Chang Liu1, Yang Yang2,3, David G Schatz4
1Department of Immunobiology, Yale School of Medicine, New Haven, CT, USA.
Nature
|November 15, 2019
まとめ
この研究は,ゲノム進化に不可欠なトランスポゼの分子機構を明らかにしています. 構造的な洞察は,適応性免疫に不可欠なRAG再結合酵素の初期の進化段階を照らしています.
科学分野:
- 構造生物学
- ゲノミクス
- 進化生物学
背景:
- トランポゾンは ゲノム進化の 重要な原動力です
- の脊椎動物における適応免疫に不可欠なRAG1-RAG2リコンビネーゼは,トランスポゼから進化したと考えられています.
- トランポゼゼの仕組みを理解することで 免疫系の進化の洞察が得られます
研究 の 目的:
- RAG1型トランポゼによるトランポゼの構造的メカニズムを解明する.
- 移行のダイナミックなプロセスを最初から最後まで捉えるため
- RAGリコンビネーゼの進化的起源を理解する
主な方法:
- X線結晶学
- 電子冷凍顕微鏡 (EM冷凍)
- トランシブの構造分析
主要な成果:
- トランシブの高解像度構造を決定し,トランスポーゼーションの全経路を記録した.
- 大変な形状の変化を 経験している蝶状の複合体を明らかにした
- RAG2のパートナーなしでトランシブへの移行を容易にするユニークな構造的特徴を特定した.
結論:
- この研究は,真核のカット&ペーストトランポゼの反応経路を詳細に説明している.
- 構造的な発見は,RAG再結合酵素の初期の進化段階を明らかにする.
- トランシブのユニークな適応は DNA再結合機構の進化の洞察を与えてくれます
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