RNAiコンポーネントは,ポリコンブ群応答要素の核クラスタリングに必要なものです
Charlotte Grimaud1, Frédéric Bantignies, Manika Pal-Bhadra
1Institute of Human Genetics, CNRS, 141 rue de la Cardonille, 34396 Montpellier Cedex 5, France.
Cell
|March 15, 2006
まとめ
Dicer-2,PIWI,およびArgonaute1を含むRNA干渉 (RNAi) 機構は,ポリコンブ群 (PcG) のタンパク質媒介遺伝子サイレンシングに不可欠である. RNAiコンポーネントは,PcG標的遺伝子の調節に不可欠な長距離DNA接触を維持しています.
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
- クロマチンの生物学
背景:
- ポリコンブ群 (PcG) タンパク質は,ポリコンブ群応答要素 (PREs) を通してホメオティックな遺伝子を静止させる重要な表遺伝子調節体です.
- PREsを含むFab-7調節要素は,複数のコピーで存在すると,PcG依存遺伝子サイレンシングを強化する長距離クロマチンの相互作用を誘導することができます.
研究 の 目的:
- PcG媒介によるFab-7要素の静止におけるRNA干渉 (RNAi) 機構の役割を調査する.
- RNAiコンポーネントが小さなRNAの生成と,トランスジェニックFab-7コピーの長距離染色体接触の維持に関与しているかどうかを判断する.
主な方法:
- Fab-7要素の複数のコピーを持つトランスジェニックのDrosophila melanogasterモデルを使用した.
- 重要なRNAi成分 (Dicer-2,PIWI,Argonaute1) の突然変異がPcGの徴募,小RNAの生成,染色体関連に与える影響を評価した.
- 顕微鏡を用いてPcG体とRNAi因子のコロカライゼーションを調査した.
主要な成果:
- RNAiコンポーネントの変異は,一般的にPcGの採用に影響することはなかったが,Fab-7コピーの間の長距離接触を維持するために不可欠であった.
- RNAi機械の構成要素は,Fab-7でのPcG媒介サイレンシングと,トランスジェニックコピーの小さなRNA生産に関与していた.
- Dicer-2,PIWI,およびArgonaute1は,PcG体と頻繁にコロカライズされ,その変異は,内生的なホメオティック遺伝子のPcG依存の染色体結合を減少させた.
結論:
- RNAi機構は,PcG染色体標的の核組織を調節する上で新しい役割を果たします.
- RNAiの成分は,強固なPcG媒介遺伝子サイレンシングに必要な高級染色体構造の確立と維持に不可欠です.
- この研究は,RNAi経路と,染色体構造による発達遺伝子の表遺伝的調節の間の機能的リンクを明らかにしています.
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