プラスティジアル・ナトリウム依存のピルバートトランスポーターである
Tsuyoshi Furumoto1, Teppei Yamaguchi, Yumiko Ohshima-Ichie
1Graduate School of Science, Hiroshima University, 1-3-1, Kagamiyama, Higashi-Hiroshima, 739-8526, Japan. tfurumoto@hiroshima-u.ac.jp
Nature
|August 26, 2011
まとめ
研究者らは,プラスチドにピルバートを輸入するために重要な新しいナトリウム結合トランスポーターであるBASS2を特定しました. この発見は,植物代謝と生物合成の経路における重要なステップを明らかにします.
科学分野:
- 植物生物学 植物生物学
- 分子生物学は分子生物学である.
- バイオケミストリー バイオケミストリー
背景:
- ピルバートは,脂肪酸とアミノ酸を含むプラスチド生物合成経路の重要な前駆体です.
- プラスチドへのピルバートの吸収の分子機構は,受動的拡散の課題のために,大部分が特徴づけられていないままです.
研究 の 目的:
- プラスチドにピルバートの輸送を担う分子機構を特定する.
- ピルベート吸収に関与する新型トランスポーターの機能と局所を特徴づける.
主な方法:
- C3とC4の植物 (フラベリアとクレオーム) の微分トランスクリプトーム解析.
- 遺伝子識別 (BASS2) とタンパク質の局所化に関する研究.
- E. coliにおける再結合タンパク質発現と輸送試験
- アラビドプシス・タリアナ・バス2変異体の分析.
主要な成果:
- BASS2 (BILE ACID:SODIUM SYMPORTER FAMILY PROTEIN 2) を,C4植物で非常に豊富に存在する新しい遺伝子として特定しました.
- BASS2はクロロプラストの封筒に局所化し,ナトリウムに依存したピルベート吸収活性を示しています.
- アラビドプシス・バス2変異種は,ピルーバートの吸収が低下し,イソペンテニル二酸化塩酸の合成に影響を与え,メバスタチンの感受性を高めています.
結論:
- BASS2は,プラスティドにピルバートの輸入を媒介するナトリウム結合トランスポーターです.
- この発見は,プラスチド包膜に含まれる重要な代謝代謝体トランスポーターの分子証拠を提供します.
- 広範囲に広がるBASS2のオートロロジは,陸上の植物の間でナトリウム結合ピルバートの輸入の重要性が保たれていることを示唆しています.
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