リボソーム依存内核酵素RelEによるmRNAの認識と分裂の構造的基礎
Cajetan Neubauer1, Yong-Gui Gao, Kasper R Andersen
1MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.
Cell
|December 17, 2009
まとめ
バクテリアのエンドヌクレアースRelEは,厳格な応答中にリボソームにmRNAを分割する. 構造研究は,RelEがA部位に結合し,トランスレーション制御のための水解経由でmRNAの分裂を引き起こすことを明らかにしています.
科学分野:
- 分子生物学は分子生物学である.
- 構造生物学 構造生物学とは
- バクテリアの遺伝学
背景:
- 翻訳制御は遺伝子発現を調節する.
- バクテリアの厳格な反応の間,mRNAはRelEエンドヌクレアゼによって分解されます.
- リボソームに対するRelEの作用のメカニズムは完全に理解されていません.
研究 の 目的:
- RelEの認識とバクテリアのリボソームへの結合の分子基盤を解明する.
- RelEによってmRNAの分裂のメカニズムを決定する.
- リボソーム依存の翻訳調節に関する構造的な洞察を提供するため.
主な方法:
- 孤立したE. coli RelEのX線結晶学と,Thermus thermophilus 70Sのリボソームと結合した.
- mRNA分裂前のおよび後のリボソーム-mRNA-RelE複合体の分析.
主要な成果:
- RelEの結晶構造は2.5 Åで,リボソーム結合RelE複合体は3.3 Åと3.6 Åで決定されました.
- RelEはリボソームのA部位を占有していることが判明しました.
- 分裂は,第2のmRNAコドンヌクレオチドの後に行われ,RelEによって促進され,水解のためのmRNAの方向転換と活性化が行われます.
結論:
- RelEのA部位への結合とmRNAと16SrRNAとの相互作用は,リボソームの要件と配列特異性を説明する.
- これらの構造は,バクテリアのmRNA分裂媒介による翻訳調節のための詳細なメカニズムを提供します.
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