KNOX2遺伝子は,陸上の植物のハプロイドから二プロイドへの形態学的移行を調節する
Keiko Sakakibara1, Sayuri Ando, Hoichong Karen Yip
1Department of Biological Science, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan. bara@hiroshima-u.ac.jp
まとめ
陸上の植物は,ハプロイド性ゲメトファイトと二倍性胞子ファイトの世代を交互に交代する. クラス2のKNOTTED1-LIKE HOMEOBOX (KNOX2) 転写因子は,この交代にとって極めて重要な二倍体段階において,ハプロイド体の計画が形成されることを防ぐ.
科学分野:
- 植物生物学 植物生物学
- 発達遺伝学 発達遺伝学
- 進化生物学の進化生物学について
背景:
- 陸上の植物は,異なる多細胞ハプロイド (ゲメトファイト) と二プロイド (スポロファイト) の体を持つ世代の交代を示しています.
- これらの世代は別々の発達プログラムによって調整され,メオシスまたは受精によって開始されます.
- 支配的な世代は様々で,モスはゲメトファイトを好み,血管植物はスポロファイトを好む.
研究 の 目的:
- 陸上の植物の世代交代を調節するクラス2のKNOTTED1-LIKE HOMEOBOX (KNOX2) 転写因子の役割を調査する.
- ハプロイドと二プロイドの相の間に,どのように異なる発達プログラムが維持されているかを理解する.
主な方法:
- モスの遺伝子分析 *Physcomitrella patens*. モスの遺伝子分析 *Physcomitrella patens*. モスの遺伝子分析 *Physcomitrella patens*.
- クラス2のKNOX2転写因子の削除.
- 二倍体胚における発達変化の観察.
主要な成果:
- *Physcomitrella patens*におけるKNOX2の削除は,二倍体胚からゲメトファイト体の発達につながった.
- この発達は,正常な微分化の過程なしに起こりました.
- KNOX2タンパク質は,二倍体段階におけるハプロイド特異の体プランを阻害することが示されました.
結論:
- クラス2のKNOX2転写因子は,二倍体性胞子体にハプロイド性ゲメトファイトの体プランが発達するのを防ぐ上で重要な役割を果たします.
- KNOX2機能の進化は,陸上の植物の世代交代を確立するために不可欠でした.
- KNOX2は,二つの世代の異なる発達経路を維持する重要なレギュレーターとして機能します.
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