siRNA経路は,ストレスにさらされた植物の世代間逆転移を防ぐ
Hidetaka Ito1, Hervé Gaubert, Etienne Bucher
1Department of Plant Biology, University of Geneva, Sciences III, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland.
Nature
|March 15, 2011
まとめ
熱ストレスはアラビドプシスのONSENレトロトランポゾンを活性化させ,小さな干渉RNA (siRNA) が欠けている子孫の世代間転移につながります. このプロセスは,新しい熱反応性遺伝子ネットワークを生成します.
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- エピジェネティクス エピジェネティクス
背景:
- ユカリオットのゲノムにはレトロトランスポゾン,すなわち,宿主の表遺伝的メカニズムによって通常抑制される移動性遺伝的要素が含まれています.
- エピジェネティック・レギュレーションが,特に環境ストレス下でのレトロトランスポゾン活動を制御する正確なメカニズムは,まだ完全に理解されていません.
研究 の 目的:
- 熱ストレス下にあるアラビドプシスの苗木におけるコピー型レトロトランポゾンONSENの活性と転移を調査する.
- ストレス時および世代を超えてONSENの逆転移を抑制する小さな干渉RNA (siRNA) の役割を解明する.
主な方法:
- アラビドプシスの苗木における熱ストレス誘導.
- ONSEN転写と染色体外DNA合成の分析.
- 植物性組織および植物世代間の植物性組織におけるONSEN転移の評価,siRNAバイオゲネシスに欠陥のある突然変異系を用いる.
- ONSEN挿入パターンの特徴と,近隣の遺伝子発現への影響.
主要な成果:
- 熱ストレスはONSENを活性化し,染色体外DNA複製合成につながります.
- siRNA経路の突然変異は,ストレス後のゲメトゲネシス中に刺激されたONSEN蓄積と世代を超えた逆転移を示します.
- ストレスを受けた突然変異体の子孫のON SEN挿入は,隣接する遺伝子に熱反応を与え,新しい規制ネットワークを形成します.
結論:
- siRNA経路は,環境によって誘発された逆転移を制限するために重要である.
- 損なわれたsiRNAバイオゲネシスは,ストレス誘発によるONSENの逆転が,特に生殖器の発達中に,世代を超えて発生することを可能にします.
- ON SENのモビリティバーストは,新しいストレス反応性遺伝子規制ネットワークを生成し,適応に貢献することができます.
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