エピジェネティック再プログラミングと,花粉の転移可能な要素の小RNAサイレンシング
R Keith Slotkin1, Matthew Vaughn, Filipe Borges
1Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
Cell
|February 11, 2009
まとめ
アラビドプシスの花粉の転移可能元素 (TEs) は,精子細胞ではなく,植物核で再活性化されます. これらのTEsから生成される小型の干渉RNA (siRNA) は,ゲメット内の静止を調節する可能性があります.
科学分野:
- 植物分子生物学 植物分子生物学
- エピジェネティクス エピジェネティクス
- ゲノミクスゲノミクスとは
背景:
- 移植可能な元素 (TEs) は変異性のリスクを伴いますが,通常は表遺伝的メカニズムと小さな干渉RNA (siRNA) によって抑制されます.
- この静止は,潜在的に有害なTE挿入の子孫への伝播を防ぐために,ゲメットにおいて極めて重要です.
研究 の 目的:
- 植物ゲメット,特にアラビドプシスの花粉におけるTEsの活性と調節を調査する.
- TEダイナミクスにおける花粉の植物核の役割と潜在的表遺伝子再プログラムを理解する.
主な方法:
- アラビドプシスの花粉におけるTE発現と転置の分析.
- TEsに関連した小さな干渉RNA (siRNA) の定量化.
- DNAメチレーションとヘテロクロマチンのリモデリングを含む表遺伝的改変の検討.
主要な成果:
- TEsは予期せぬ形で活性化し,シゴトにDNAを寄与しない細胞である花粉の植物性核内に転移する.
- TE再活性化は,ヘテロクロマチンのリモデレータ"DNAメチル化1の減少"と減少したTE siRNAのダウンレギュレーションと相関しています.
- Athilaのレトロトランポゾンから派生した21核酸 siRNAは,花粉と精子細胞の両方で生成され,蓄積されます.
結論:
- TEsは,雄性ゲメトファイト内の特定の仲間細胞 (植物性核) で再活性化することができます.
- ゲメット内のsiRNAの蓄積は,潜在的に再活性化されたTEから発生する,TEサイレンシングを標的とするメカニズムを示唆する.
- ゲルムラインの仲間細胞での再プログラミングは,種間のゲメットのTE活性を調節する保存されたメカニズムである可能性があります.
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