プリオンは,野生の酵母菌における表型遺伝の一般的なメカニズムである

Randal Halfmann¹, Daniel F Jarosz, Sandra K Jones

¹Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, Massachusetts 02142, USA.

Nature

|February 17, 2012

まとめ

イーストのプリオン,または自己テンプレートタンパク質は,野生の株で一般的であり,多様な有益な特性を授与します. これらのエピジェネティック要素は,自然集団の適応と進化を促すことができます.

科学分野:

* 分子生物学について
* 遺伝学について
* 進化生物学について

背景:

*酵母プリオンは自己テンプレートするタンパク質で,表遺伝的要素として作用し,潜在的に遺伝的現象型多様性と適応を誘導する可能性があります.
* 自然の集団におけるプリオンの役割と進化への貢献は論争の的であり,一部の研究者はそれを希少な実験器として見ています.

研究の目的:

*野生のSaccharomyces菌株における酵母プリオン ([PSI(+) と[MOT3(+) ]の有病率と機能的重要性を調査する.
* これらのプリオンが選択的条件下で有益なフェノタイプを与え,適応的進化に寄与するかどうかを判断する.

主な方法:

* 野生のサカロマイセスの約700株の生物化学検査で[PSI (+) ]または[MOT (+) ]プリオンが検出されました.
*野生の株における未知のプリオン元素を特定するための遺伝子スクリーニング.
* 選択条件下でプリオンを含む株のフェノタイプ分析.

主要な成果:

* [PSI(+) ]と[MOT3(+) ]プリオンは,研究室の菌株だけでなく,多くの野生のサッカロミセス菌株で発見されました.
* これらのプリオンは多様でしばしば有益な現象型を与え,選択的圧力下での生存を助けました.
* 野生の菌株の3分の1には未知のプリオン元素が含まれており,多様でしばしば有利な現象型も生み出していた.
* 有益な特徴は,媒介的な再分類によってプリオン独立になり,迅速な適応を示している.

結論:

*酵母プリオンは自然界に広く存在し,遺伝的特徴を制御する上で重要な役割を果たします.
*プライオンは現象型多様性に寄与し,適応上の利点を提供し,進化の機会を拡大する.
*この発見は,プリオンが希少疾患であるという認識に異議を唱え,自然進化におけるプリオンの大切さを強調しています.

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