Piwiと相互作用するRNAは,Oxytrichaのゲノム再編成中にDNAの損失からDNAを保護します
Wenwen Fang1, Xing Wang, John R Bracht
1Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
Cell
|December 11, 2012
まとめ
オキシトリカの母核ガイドゲノムプログラミングからのピウィ相互作用RNA (piRNAs). これらの小さなRNAは,世代を超えたエピジェネティックキャリアとして作用し,必須のDNAの保持を保証します.
科学分野:
- エピジェネティクスと分子生物学
- ゲノミクスと遺伝に関する研究.
- シリアド原生虫の研究
背景:
- Oxytrichaのようなシリアド原生体は,独特の体内ゲノムと生殖系統ゲノムを持つゲノム二重性を表しています.
- ソマティックゲノム開発には,トランポゾンを含む生殖系DNAの ~95% のプログラムされた除去が含まれます.
- この選択的DNA除去のメカニズムを理解することは,遺伝とゲノム調節を理解するために不可欠です.
研究 の 目的:
- オキシトリカにおける体性ゲノム発達の過程で保持されるゲノム領域を特定する際に小RNAの役割を調査する.
- 母親のPiwi相互作用RNA (piRNA) が次の世代のためにゲノムの表遺伝的プログラミングを指示できるかどうかを決定する.
- エピジェネティック情報のトランスジェネレーションキャリアとしての小RNAの潜在能力を探求する.
主な方法:
- オキシトリカのpiRNA集団の分析と,そのマッピングを生殖系統と体性ゲノムに.
- 通常削除されたゲノム領域に対応する合成のpiRNAを開発中の核に注入する.
- 挿入されたゲノム領域が次の世代に保持される評価.
主要な成果:
- オキシトリカのpiRNAは,主として体内ゲノムを構成する生殖系DNAの ~5%を保持している.
- 母親のpiRNAは,DNA除去プロセス中に保持されるゲノム領域を指定します.
- 通常削除された領域を標的とした合成のpiRNAは,後の世代でそれらの保持を成功裏に誘導しました.
結論:
- ピウィ相互作用RNA (piRNAs) は,オキシトリカの世代間における表遺伝情報伝達の主要な媒介者である.
- 小型RNAは,ゲノムプログラミングの重要な決定因子として作用し,DNAの選択的な保持を導く.
- この研究は,小さなRNAによって媒介される,世代を超えたエピジェネティック継承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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