リボソームによるtRNAの選択には,開いた形から閉じた形への移行が必要です

James M Ogle¹, Frank V Murphy, Michael J Tarry

¹MRC Laboratory of Molecular Biology, Hills Road, CB2 2QH, Cambridge, United Kingdom.

Cell

|December 5, 2002

まとめ

転送RNA (tRNA) のリボソーム選択は構造的に説明されています. 近縁性tRNAは不都合に溶解され,正確なtRNA選択のために閉じた30Sリボソームサブユニット構成を必要とします.

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
バイオケミストリーバイオケミストリー

背景:

タンパク質合成中に正しい転送RNA (tRNA) を選択するリボソームのメカニズムは,まだ完全に理解されていません.
翻訳的忠誠性を理解することは,遺伝子発現と疾患メカニズムを解読する上で極めて重要です.

研究の目的:

リボソームによるtRNA選択のための構造的およびメカニズム的基礎を提供すること.
転写フィデリティにおけるリボソーム構成の役割を明らかにする.

主な方法:

コドンと近縁のtRNAアンチコドン幹のループに結合した30SリボソームサブユニットのX線結晶学.
対応するリボソーム-tRNA複合体の溶液ベースの親和度測定.

主要な成果:

結晶構造は,近縁のtRNAが30S解読センターとどのように相互作用するかを明らかにします.
近縁の相互作用におけるワトソン・クリック幾何学からの偏差は,不利な溶解を引き起こします.
関連性tRNAによって誘発される閉じた30S構成は,選択に不可欠であり,パロモミシンのようなヘルパー分子のない近似性tRNAには不利である.

結論:

閉じた30Sリボソームサブユニット構成の安定化は,正確なtRNA選択のための重要な要件です.
この構造的メカニズムは,翻訳的忠誠性とパロモミシンなどの抗生物質の効果に関する以前の観察を説明します.

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