バクテリアエフェクターは,植物転写因子として作用し,細胞サイズレギュレータを誘導します
Sabine Kay1, Simone Hahn, Eric Marois
1Institute of Biology, Department of Genetics, Martin-Luther-University Halle-Wittenberg, Weinbergweg 10, D-06120 Halle (Saale), Germany.
Science (New York, N.Y.)
|October 27, 2007
まとめ
Xanthomonasバクテリアは,AvrBs3タンパク質を植物細胞に注入し,細胞の成長を引き起こします. AvrBs3は植物の転写因子を模倣して宿主細胞を再プログラムし,新しい病原性メカニズムを明らかにします.
科学分野:
- 植物-病原体相互作用
- 分子植物病理学 分子植物病理学
- バクテリアのエフェクタータンパク質.
背景:
- グラム陰性バクテリアは,III型分泌システムを使用して,受容体細胞にエフェクタータンパク質を注入します.
- これらのエフェクターは,病原体の利益のために宿主経路を操作します.
- ザントモナスのAvrBs3は,植物細胞核を標的とするIII型エフェクターです.
研究 の 目的:
- AvrBs3が植物細胞高縮を誘発する分子メカニズムを解明する.
- AvrBs3.3によって調節される宿主標的遺伝子を識別する.
- AvrBs3が植物細胞の発達をどのように操作するかを理解するために.
主な方法:
- 植物細胞におけるAvrBs3の局所化と機能の分析.
- AvrBs3誘発の標的を特定するための遺伝子発現分析.
- AvrBs3の結合部位を決定するためのプロモーター分析.
主要な成果:
- AvrBs3は,植物細胞サイズの主調節体であるupa20の発現を誘導する.
- upa20は,基本的なヘリックス・ループ・ヘリックス・ドメインを持つ転写因子をコードします.
- AvrBs3 は upa20 プロモーターに結合し,その転写を活性化します.
結論:
- AvrBs3は,UPA20発現を誘導することによって,植物細胞の発達を再プログラムします.
- AvrBs3は,転写因子を模倣し,宿主の調節経路をハイジャックする機能を持っています.
- このメカニズムは,細菌エフェクターが,真核転写因子機構をどのように利用できるかを強調しています.
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