UAP56は,ピRNAクラスターを,周核トランポゾン静音化装置と結び付けます
Fan Zhang1, Jie Wang2, Jia Xu2
1Program in Cell and Developmental Dynamics, University of Massachusetts Medical School, Worcester, MA 01655, USA; Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01655, USA.
Cell
|November 13, 2012
まとめ
DEADボックスタンパク質UAP56は,Drosophilaの生殖線発達におけるpiRNAを処理するためにVasaと相互作用する. この相互作用は,トランポゾン静音化に不可欠であり,核の封筒に及ぶ.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学について
背景:
- PIWI相互作用RNAs (piRNAs) は,生殖系統発達の過程で転移可能な要素を静止するために不可欠です.
- ドロソフィラでは,piRNAのバイオゲネシスは,周核雲で処理されたヘテロクロマティッククラスターからのトランスクリプトで開始されます.
- DEADボックスタンパク質UAP56とVasaは,PIWIタンパク質とともに,piRNAの生成と局所化に関与しています.
研究 の 目的:
- UAP56のpiRNA生殖における役割と,Vasaとの関係を調査する.
- piRNA処理の文脈でUAP56の細胞下部局所と機能的相互作用を解明する.
- UAP56が生殖系におけるトランポゾン静止に寄与するメカニズムを理解する.
主な方法:
- UAP56,Rhino,およびVasa.の間の空間的関係を決定するための免疫局所化研究.
- 免疫プレシピテーションは,クラスタートランスクリプトと相互作用するタンパク質を特定するための測定法です.
- UAP56変異体の分析により,piRNAの生成,トランポゾンサイレンシング,タンパク質の局所化への影響を評価した.
主要な成果:
- UAP56は,クラスター焦点のヘテロクロマティックタンパク質Rhinoとコロカライズする.
- ワサを含む雲粒子はUAP56/ライノノの焦点から核封筒に横断して配置されています.
- クラスタートランスクリプトはVasaとUAP56の両方と相互作用し,UAP56の変異はこれらの相互作用とpiRNAの生殖を妨げます.
結論:
- UAP56とVasaは,核封筒を横断するpiRNA処理コンパートメントで一緒に機能します.
- このUAP56-Vasa複合体は,生殖細胞のpiRNA生成と効果的なトランポゾン静音化に不可欠です.
- この発見は,核封筒に及ぶ相互作用を含むpiRNA生体生成のための新しいメカニズムを明らかにしています.
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