THO/Sub2pの機能は,3'-end処理と遺伝子-核毛孔関連を調整する機能です
Mathieu Rougemaille1, Guennaelle Dieppois, Elena Kisseleva-Romanova
1LEA Laboratory of Nuclear RNA metabolism, Centre de Génétique Moléculaire, Centre National de la Recherche Scientifique - UPR2167, 1, av de la Terrasse, 91190, Gif sur Yvette, France.
Cell
|October 30, 2008
まとめ
THO複合体とSub2pヘリケーゼは,メッセンジャーリボ核タンパク質粒子の (mRNP) 生成に不可欠である. 変異はmRNPの輸出を停止し,THO/Sub2pを明らかにした.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子発現の表現について
- RNA 処理 RNA 処理
背景:
- メッセンジャーリボ核タンパク質粒子 (mRNP) は,転写中に形成されます.
- THO複合体とSub2pヘリケーゼは,転写とmRNPの生殖に関与しています.
- これらのプロセスにおけるそれらの正確な役割は完全に理解されていません.
研究 の 目的:
- mRNPのバイオゲネシスと遺伝子発現におけるTHO複合体/Sub2pの機能を明らかにする.
- THO複合体/Sub2p.によって調節される遺伝子を識別する.
- mRNP熟成においてTHO/Sub2pが作用する特定のステップを決定する.
主な方法:
- イーストにおけるTHO/Sub2p変異体の分析.
- 停止したmRNP中間物質の特性.
- 遺伝子発現のマイクロアレイ分析.
- 核孔およびポリアデニレーション因子の局所化研究.
主要な成果:
- THO/Sub2p変異は,クロマチンと関連した核孔とポリアデニレーション因子を含んだ停滞したmRNP中間物質を引き起こす.
- マイクロアレイ分析により,発現のためにTHO/Sub2pを必要とする約400の新しい標的遺伝子が特定されました.
- これらの標的遺伝子は,突然変異体の核孔に異常にドッキングされています.
結論:
- THO複合体/Sub2pは,mRNPの輸出能力につながるイベントの調整に不可欠です.
- この機能は,3'-処理へのコミットメント後,核輸出前に必要となります.
- THO/Sub2pは,mRNPの成熟を促進することによって,効率的な遺伝子発現を確保する上で重要な役割を果たします.
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