ユカリオットトランスレーションのインビトロ再構成では,放出因子 eRF1 と eRF3 の間の協力性を明らかにしています

Elena Z Alkalaeva¹, Andrey V Pisarev, Lyudmila Y Frolova

¹Department of Microbiology and Immunology, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA.

Cell

|June 17, 2006

まとめ

ユカリオットのトランスレーション終結には,ペプチド放出因子 eRF1 と eRF3.3 が含まれる. この研究は, eRF3によるポリペプチドの放出における彼らの協力的作用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.
タンパク質合成タンパク質合成
細胞生物学細胞生物学

背景:

ユカリオットのトランスレーション終結は,タンパク質合成の重要なプロセスです.
ペプチド放出因子1 (eRF1) は,ストップコドンを認識し,ペプチジルtRNAを水分解する.
終結におけるペプチド放出因子3 (eRF3) の正確な機能は,ほとんど不明のままである.

研究の目的:

ユカリオットのトランスレーション終結における eRF3 の機能を明らかにする.
eRF1とeRF3の協力行動のためのメカニズムモデルを提案する.

主な方法:

精製された成分を用いて,真核細胞の翻訳を再構成 in vitro.
テトラペプチドをコードするmRNAにプレターミネーション複合体の組み立て.
トーインプリント検査は,終了時に構造的再配置を監視するために行われます.

主要な成果:

eRF1とeRF3の協力行動を含む翻訳終了のモデルが提案されました.
eRF1,eRF3,GTPの結合により,構造的な再配置とGTPの水解が引き起こされます.
その後,ペプチジルtRNAの急速な水解が行われ,急速な新生ポリペプチドの放出が保証されます.
eRF1とeRF3の間の協力は,eRF1のC端末ドメインに依存しています.

結論:

eRF3は,効率的な真核細胞の翻訳終結において重要な役割を果たします.
eRF1とeRF3の相互作用は,ポリペプチドの放出速度を高めます.
これらの要素を含む翻訳終了メカニズムの詳細なモデルが確立されています.

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