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ヒプシンを含むタンパク質eIF5Aは,トランスレーション延長を促進する
Preeti Saini1, Daniel E Eyler, Rachel Green
1Laboratory of Gene Regulation and Development, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA.
Nature
|May 9, 2009
まとめ
独特のアミノ酸ヒプシンを含む翻訳因子eIF5Aは,タンパク質合成に不可欠です. この研究は,eEF2.2と共にリボソーム転位を支援することによって,eIF5Aが開始ではなく,翻訳延伸を促進することを実証しています.
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
- 遺伝学 遺伝学とは
背景:
- EF-TuやEF-Gのような翻訳延長因子は,タンパク質合成に不可欠です.
- eIF5Aは,ヒプシンを含むユニークなエウカリオット因子であり,以前は翻訳開始を支援すると考えられていた.
- 細胞過程におけるeIF5Aの正確な機能は不明であり,mRNAの分解と輸送と関連している.
研究 の 目的:
- 翻訳因子eIF5Aの細胞における正確な役割を明らかにする.
- eIF5Aがトランスレーション開始または延長で機能するかどうかを調査する.
- eIF5Aがタンパク質合成に影響を与えるメカニズムを決定する.
主な方法:
- Saccharomyces cerevisiaeにおける分子遺伝学的研究について.
- バイオケミカルアッセイ,インビトロ合成を含む.
- ポリソームの蓄積とリボソーム通過時間の分析.
- eIF5A.の無効化と枯渇
- リコンビナントeIF5Aの活性をテストする.
主要な成果:
- eIF5Aの枯渇または無活性化により,ポリソームの蓄積が起こり,酵母体におけるリボソーム通過時間が増加しました.
- リコンビナントeIF5Aですが,ヒプスレス派生体ではありません. in vitroトリペプチド合成で強化されています.
- eIF5A不活性化は,eEF2阻害体ソルダリンの効果を模倣した.
- eIF5Aは構造的に細菌のEF-P.に同型である.
結論:
- eIF5Aは翻訳延長因子であり,主としてイニシアチブには関わらない.
- eIF5Aはリボソーム転位を促進し,eEF2と潜在的に協力します.
- eIF5A/EF-Pファミリーは,普遍的に保存される翻訳延長因子を表しています.
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