受精した卵細胞は,ポリチュービーを避けるためにエンドペプチダゼを分泌する
Xiaobo Yu1, Xuecheng Zhang1, Peng Zhao1
1State Key Laboratory of Hybrid Rice, College of Life Sciences, Wuhan University, Wuhan, China.
Nature
|April 1, 2021
まとめ
植物卵細胞は,ECS1とECS2を分泌することで,受精後に多重な花粉管の侵入を防ぐ. これらの酵素はLURE1の誘導物質を分解し,さらに花粉管の誘導を阻害し,受精を成功させる.
科学分野:
- 植物生殖生物学
- 受精の分子メカニズム
背景:
- 動物の卵細胞は受精封筒を通して多精子を遮断する.
- 植物の受精は花粉管が 精子を卵子に運ぶことを意味します
- 多精子症は通常,多重な花粉管の浸透を防ぐことで避けられる.
研究 の 目的:
- 植物の卵細胞が受精後に余分な花粉管の排泄を制御する方法を調査する.
- 植物における受精後の多精子症の基礎となる分子機構を特定する.
主な方法:
- アラビドプシスの卵細胞でアスパルティックエンドペプチダゼECS1とECS2を研究した.
- ECS1とECS2の分泌,発現,および基板特異性を分析した.
- LURE1に対するECS1とECS2の効果を研究した.
- ecs1 ecs2 の二重変異体および子宮内ペプチダース分泌のポリチュービーの頻度を調べた.
主要な成果:
- ECS1とECS2は受精後にアラビドプシスの卵細胞から分泌されます.
- ECS1とECS2は,花粉誘導体LURE1を特異的に裂く.
- ecs1 ecs2のダブルミュータントは 頻繁にポリチュービリティを示します
- ECS1/ECS2の子宮外分泌は,LURE1のレベルと花粉管の引き寄せを減少させます.
結論:
- 植物卵細胞は受精を感知し,受精後のブロックをポリチュービーに確立します.
- ECS1とECS2の受精による分泌はLURE1を分解し,さらに花粉管の引き寄せを防ぐ.
- このメカニズムは,開花植物における単一精子を保証する.
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