菌類の二形態化と毒性のグローバルコントロール
Julie C Nemecek1, Marcel Wüthrich, Bruce S Klein
1Department of Medical Microbiology and Immunology, University of Wisconsin Medical School, University of Wisconsin Hospital and Clinics, Madison, WI 53792, USA.
Science (New York, N.Y.)
|April 29, 2006
まとめ
新たに特定されたハイブリッドヒスティジンキナーゼは,二形キノコ病原体におけるカビから酵母への切り替えを調節する. このグローバル・レギュレータは,哺乳類の宿主への適応に不可欠であり,毒性と病気に影響を与えます.
科学分野:
- 菌類学 菌類学とは
- 病原体の適応 病原体の適応
- 分子生物学は分子生物学である.
背景:
- ダイモルフキノコは,哺乳類の宿主体内で,環境のカビから病原菌酵母へと移行する.
- この温度に依存する形態学的スイッチは,真菌の毒性にとって不可欠であるが,よく理解されていない.
- 6種の二形菌は,地球規模で重大な病気を引き起こす.
研究 の 目的:
- 菌類の病原体における二形変異を制御する分子メカニズムを解明する.
- 主体信号を感知し,酵母型スイッチを誘発する重要なレギュレータを特定する.
- 菌類の病原性および宿主適応におけるこの調節体の役割を理解する.
主な方法:
- 変形性菌の遺伝子発現とタンパク質機能を研究した.
- キナーゼ活性とその効果を研究するために遺伝子操作を用いた.
- ウイルス性遺伝子発現と細胞壁の整合性を in vivo および in vitro で評価した.
主要な成果:
- ハイブリッドヒスティジンキナーゼは,宿主信号の重要なセンサーとして特定されました.
- このキナーゼは,宿主に関連する刺激にさらされると,菌類から酵母への移行を直接引き起こす.
- キナーゼはまた,細胞壁の整合性,胞子形成,ウイルス性遺伝子発現を制御する.
結論:
- 単一のハイブリッドヒスティジンキナーゼは,二形態キノコの適応のグローバルレギュレータとして作用します.
- この調節体は,哺乳類の宿主体内で真菌の生存と毒性を保つために不可欠です.
- このキナーゼを標的にすることは,全身性真菌感染症の治療のための潜在的な戦略を提供します.
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