ポリペプチド連鎖解放因子の特性を有する高度に保存された真核タンパク質ファミリー
L Frolova1, X Le Goff, H H Rasmussen
1Department of Molecular Biology, University of Aarhus, Denmark.
Nature
|December 15, 1994
まとめ
科学者は,エウカリオットのタンパク質合成を終了するために不可欠な保存されたタンパク質ファミリー,eRF1を特定しました. この発見は,ユカリオット放出因子 (RFs) の翻訳終結における機能を明らかにする.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- バイオケミストリー バイオケミストリー
背景:
- タンパク質合成の終結は,ストップコドンと放出因子 (RF) によって調節されます.
- プロカリオットおよびミトコンドリアRFの構造は知られているが,真核RF (eRF) の構造は不明である.
- 単一のエウカリオットRF (eRF) が認識されていますが,そのアイデンティティと機能は明らかにする必要があります.
研究 の 目的:
- 翻訳終結に関与するエウカリオット放出因子 (eRF) を特定し,特徴づけること.
- 異なる真核生物種における潜在的 eRF の構造的および機能的類似性を調査する.
- タンパク質合成の終結における特定されたタンパク質の役割を確認する.
主な方法:
- 配列分析は,エウカリオット全体で保存されたタンパク質ファミリーを特定するために行われます.
- イーストとE. coli. での候補タンパク質の異質表現.
- タンパク質の活性性をテストするためのインビトロ放出因子アッセイ.
- Saccharomyces cerevisiae sup45 (sup1) の機能分析を翻訳したものです.
主要な成果:
- 関連するタンパク質の保存されたファミリー, eRF1 と指定され,下位および上位エウカリオットで特定されました.
- 人体およびXenopus laevis eRF1タンパク質は,発現,浄化され,in vitro RFアッセイで活性が実証されました.
- サッカロマイセス・セレヴィシアのタンパク質sup45 (sup1) は,eRF1ファミリーの1つで,翻訳抑制に関与しています.
- eRF1ファミリー内のアミノ酸配列の高い保存が観察されました.
結論:
- eRF1タンパク質ファミリーは,真核生物における翻訳の終結に直接関与しています.
- eRF1タンパク質は,多様な真核生物体において,構造的にも機能的にも保存されています.
- この発見は,真核の放出因子のアイデンティティと機能に関する長年の疑問を解決します.
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