宿主植物ゲノムは,共生的な窒素固定のための細菌の遺伝子の欠如を克服します
Tsuneo Hakoyama1, Kaori Niimi, Hirokazu Watanabe
1National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
Nature
|November 27, 2009
まとめ
ロータス・ジャポニカスのFEN1遺伝子はホモシトラート合成酶 (HCS) をコードし,NifV.欠乏した豆類の窒素固定を可能にします. 宿主由来ホモサイトレートは,共生性リゾビアにおける窒素酶合成に不可欠である.
科学分野:
- 植物と微生物の共生です.
- 窒素固定の生化学について
背景:
- 窒素の固定は,植物の成長に不可欠です.
- ホモシトラート合成酵素 (HCS) は,窒素酵素の活性に不可欠です.
- ほとんどのリゾビアにはHCSのためのNifV遺伝子が欠けていますが,共生的な窒素固定を行います.
研究 の 目的:
- Lotus japonicus FEN1遺伝子のシンビオティックな窒素固定における役割を調査する.
- FEN1がリゾビアにおけるNifVの欠乏を補うことができるかどうかを判断する.
主な方法:
- 効果のない結節を持つ植物変異体 (fen1) を特徴づけた.
- HCS欠陥酵母変異体をFEN1遺伝子で補完した.
- 改変されたリゾビアまたは外因的なホモシトラートを提供するフェン1変異体を接種した後の窒素固定活性評価.
主要な成果:
- フェン1変異体は,ホモサイトレートが欠け,無効な結節を形成した.
- FEN1はHCSをコードし,HCS不足の酵母を補完する.
- FEN1またはNifVは,fen1ノードルに窒素固定を回復した.
- 外因的ホモサイトレートは,フェン1ノードルにおける救助された窒素固定.
結論:
- 宿主由来ホモサイトレートは,リゾビアル菌類のバクテロイドにおける窒素酶合成に不可欠である.
- 豆類FEN1遺伝子はHCS活性を提供し,共生的な窒素固定を可能にします.
- これは,豆類-リゾビア共生にとって不可欠な補完的なパートナーシップを強調しています.
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