エリソイド分化におけるmRNAサイレンシング: hnRNP Kとhnrp E1は,3'端から15-リポキシゲナーゼ翻訳を調節する
D H Ostareck1, A Ostareck-Lederer, M Wilm
1Gene Expression Programme, European Molecular Biology Laboratory, Meyerhofstrasse, Heidelberg, Germany.
Cell
|May 16, 1997
まとめ
異質な核リボヌクレオプロテインK (hnRNP K) とE1 (hnRNP E1) の2つのタンパク質は,細胞分化中にLOX mRNA翻訳を静止することによって遺伝子発現を調節する. 特定のmRNA配列のリボソーム組成を阻害する.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 遺伝子規制 遺伝子規制
背景:
- LOX mRNAはエリトロポエーシスの初期に蓄積するが,後期まで翻訳的に静止される.
- LOX mRNAの3'未翻訳領域にある特定の要素が,この分化依存性静止を制御する.
研究 の 目的:
- LOX mRNAの翻訳サイレンスに起因するタンパク質を特定する.
- これらのタンパク質が翻訳を調節するメカニズムを解明する.
主な方法:
- ウサギの網膜細胞からの静止タンパク質の浄化.
- ヘラ細胞をレポーターmRNAと特定されたタンパク質で感染させる.
- LOX mRNA と hnRNP K. の共免疫プレシピテーション
- 再結合タンパク質による細胞フリートランスレーションシステムの再構成.
主要な成果:
- hnRNPs KとE1は,LOXサイレンシングを媒介するタンパク質として特定されました.
- hnRNP KとE1による感染は,レポーターmRNAの翻訳を沈黙させた.
- hnRNP Kは,静止されたLOX mRNAと特異的に共免疫的に precipitated.
- リコンビナント hnRNP KとE1は,LOX mRNAの80Sリボソームアセンブリを in vitroで阻害しました.
- 両方のタンパク質は,キャップ依存およびIRES媒介翻訳を調節する.
結論:
- hnRNP KとE1は,特定の細胞質の翻訳調節体として作用する.
- これらのhnRNPは,遺伝子発現を制御するために,分化制御要素と結合します.
- この発見は,翻訳制御における hnRNP の新しい細胞質の機能を明らかにしています.
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