遺伝子発現は円形である:mRNAの分解の要因は,mRNAの合成も促進する
Gal Haimovich1, Daniel A Medina, Sebastien Z Causse
1Department of Molecular Microbiology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
Cell
|May 28, 2013
まとめ
ほとんどの酵母mRNAは,細胞質5'-to-3'-腐敗経路によって分解される. この経路の欠陥は驚くほど,転写のダウンレギュレーションにつながり,円形の遺伝子発現プロセスを明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- イースト遺伝学 イースト遺伝学
背景:
- 遺伝子発現の調節は,正確なmRNAレベルを維持することに依存しています.
- mRNAレベルは,合成と分解のバランスによって決定されます.
- 細胞プラズマの5o3ext経路 (decaysome) は,主要なmRNA分解経路である.
研究 の 目的:
- 腐敗細胞経路における干渉に対するmRNAレベルの強度を調べる.
- mRNAレベル安定の基礎となるメカニズムを解明する.
- 細胞プラズマのmRNAの崩壊を超えて,分解体構成要素の潜在的な役割を探求する.
主な方法:
- 腐敗した部分に欠陥がある酵母菌株におけるmRNA濃度の分析.
- 分解体タンパク質のサブセルラー局所化とクロマチン結合の調査.
- 核分解の機能が転写に与える影響を評価するためのアッセイ.
主要な成果:
- mRNAレベルは,腐敗経路の欠陥に対して驚くほど堅牢です.
- 分解性コンポーネントの欠陥は,mRNA転写のダウンレギュレーションを誘発する.
- 分解体成分は,細胞質と核の間を移動し,転写開始部位の近くのクロマチンと結合して,開始と延長を刺激します.
結論:
- 腐敗体は,mRNAの分解と転写の調節の両方で二重の役割を果たします.
- 転写における腐敗体の核機能は,タンパク質のシャトルリングによるmRNAの崩壊におけるその細胞質の役割と関連しています.
- 遺伝子発現は,転写とmRNAの分解を結びつける循環的な規制メカニズムを示しています.
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