アグロバクテリアの毒性プラズミドの予期せぬ保存と世界的な伝播
Alexandra J Weisberg1, Edward W Davis1,2, Javier Tabima1
1Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.
Science (New York, N.Y.)
|June 6, 2020
まとめ
アグロバクテリアのような病原菌は 毒性プラズミッドを使って 植物に感染します 驚くべきことに これらの腫瘍性プラズミドは 数少ない系統から発生し 伝播によって グローバルに広がり 多様化しています
科学分野:
- 微生物学
- 進化生物学
- 植物病理学
背景:
- 病原体の進化と拡散は 宿主種に重大な脅威をもたらします
- アグロバクテリアは,腫瘍性TiまたはRiプラズミッドを植物遺伝子転送および疾患誘導に使用します.
研究 の 目的:
- 毒性プラズミドを特徴付けるための戦略を開発する.
- アグロバクテリアにおける腫瘍性プラズミドの進化史と流行病学的パターンを分析する.
主な方法:
- ウイルス性プラズミドの特徴化のための新しい戦略を開発した.
- 多様な宿主種から世界中で収集された数百のアグロバクテリア株 (1927年−2017年) を分析した.
- プラズミッドの可塑性に影響を与える特徴を特徴づけることで,進化史を推論した.
主要な成果:
- 高度な再結合の期待に反して,腫瘍性プラズミッドは,いくつかの保存された系統から派生しています.
- プラズミドの進化的可塑性を促進または抑制する重要な特徴を特定した.
- 病原体の多様化と拡散におけるプラズミド伝播の重要な役割を示す疫学的パターンを明らかにした.
結論:
- プラズミド伝播は,アグロバクテリアの多様化,持続性,世界的な拡散の重要な要因です.
- 腫瘍性プラズミドの進化軌道は,限られた数の保存された系統によって形成されています.
- プラズミドの進化を理解することは,アグロバクテリアによって引き起こされる植物病の管理に極めて重要です.
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