ドロソフィラのパラミューテーションは,piRNAを生成する場所の出現と関連しています
Augustin de Vanssay1, Anne-Laure Bougé, Antoine Boivin
1Laboratoire Biologie du Développement, UMR7622, CNRS-Université Pierre et Marie Curie, 9 quai Saint Bernard, 75005 Paris, France.
Nature
|August 28, 2012
まとめ
パラミューテーションは,動物の世代を超えてトランスゲンをエピジェネティックに沈黙させます. このプロセスは,piRNAsによって媒介され,非静音化トランスゲンを強力なエピジェネティックサイレンサーに変換し,新しいpiRNAロシエを確立します.
科学分野:
- エピジェネティクス エピジェネティクス
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- パラミューテーションは,DNA配列の変化なしにアレルの遺伝性表遺伝子改変を伴う.
- トランスサイレンス効果 (TSE) は,P-トランスポーザブル要素のホモロジー依存型サイレンスメカニズムである.
- パラミューテーションは,代々の間,長期間,表遺伝子状態の伝播につながる可能性があります.
研究 の 目的:
- 長期にわたる世代間伝播を伴う動物におけるパラミューテーションの新しい症例を記述する.
- パラミューテーションを媒介するPiwi相互作用RNAs (piRNAs) の役割を調査する.
- piRNAロシの出現と世代を超えた抑圧のための遺伝モデルを確立する.
主な方法:
- TSEを誘発できるP元素由来トランスゲンクラスタを研究した.
- 非TSEのトランスゲンクラスターを強力なサイレンサーに変換することを調査しました.
- piRNAsを含む細胞質の母性遺伝の役割を分析した.
- パラミューテーションに対するアベルギンとDicer-2変異の影響を調査した.
主要な成果:
- 強いTSEを誘発するP要素のトランスゲンクラスターは,同類のTSE以外のクラスターを50世代に渡って強いサイレンサーに変換した.
- パラミューテーションは染色体ペアリングなしに発生し,母親のpiRNAsによって媒介されました.
- 機能喪失アベルギン変異は抑制を廃止したが,Dicer-2変異はそうしなかった.
- パラミュテートされたロシは,安定した,強力なpiRNA生産者となり,それ自体がパラミュタゲンであった.
結論:
- この研究は,piRNAsによって媒介される動物におけるパラミューテーションの遺伝モデルを示しています.
- この発見は,移植可能な要素のRNA媒介による世代間抑制を示しています.
- パラミューテーションは,機能的なpiRNAロシオのデノボの出現につながる可能性があります.
関連する概念動画
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