イーストのLaタンパク質は,tRNA前駆体を成熟させる3'-エンドヌクレオリチス分裂に必要である
1Department of Cell Biology, and Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
Cell
|May 2, 1997
まとめ
Laタンパク質 (Lhp1p) は,酵母tRNAの成熟に不可欠である. エンドヌクレオリチス分裂のためのプレ-tRNAを安定させ,エクソヌクレアースの分解を防止することにより,適切な3'-エンド処理を保証します.
科学分野:
- 分子生物学は分子生物学である.
- イースト遺伝学 イースト遺伝学
- RNA 処理 RNA 処理
背景:
- La自己抗原 (酵母におけるLhp1p) は,新生ポリメラーゼIIIのトランスクリプトに結合する.
- そのin vivoの機能,特にtRNAの成熟については,ほとんど知られていなかった.
- Lhp1pが欠けている酵母は生存可能ですが,特定のtRNA変異により,Lhp1pが成長するために必要になります.
研究 の 目的:
- 酵母におけるLaタンパク質ホモログLhp1pのインビボ機能を解明する.
- Lhp1pが特定のプレ-tRNAs,特にtRNA(Ser) CGA.の成熟における役割を調査する.
- Lhp1pが3'トレーラーシーケンスの処理をどのように促進または制御するかを理解するために.
主な方法:
- 野生型および変異性プレ-tRNA (((Ser) CGA.の酵母菌株の遺伝子分析
- Lhp1p欠乏酵母菌のフェノタイプ分析
- プレ-tRNA処理経路 (エンドヌクレオリチス対エクソヌクレオリチス) を評価するための生化学分析.
主要な成果:
- Lhp1pは,ワイルド型プレ-tRNAから3'トレーラー配列のエンド核分解除去に不可欠です.
- Lhp1pが存在しない場合,3'トレーラーがエクソヌクレアゼによって分解される.
- Lhp1pの変異性前tRNA ((Ser)) CGA成熟の必要性は,アンチコドン幹の塩基配列の復元によって廃止されます.
結論:
- Lhp1pは,プリ-tRNAを安定させ,3'内核分解分裂のための正しい構成を促進します.
- この安定化メカニズムは,酵母における効率的で正確なtRNA成熟に不可欠です.
- この発見は,Lhp1pが処理中のtRNA前駆体の完全性を確保する上で特定の役割を果たしていることを明らかにしています.
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