翻訳の表遺伝子調節は,複雑な特徴を生み出すために隠された遺伝的多様性を明らかにします
Heather L True1, Ilana Berlin, Susan L Lindquist
1Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA.
Nature
|August 18, 2004
まとめ
酵母プリオン[PSI(+) ]は,無意味なコドンを読み込むことによって,細胞が様々な状況で生き残ることを可能にします. この表遺伝的要因は,複雑な特徴の獲得と安定化を促進し,進化に影響を与えます.
科学分野:
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
- 遺伝学 遺伝学とは
背景:
- フェノタイプ性可塑性や隠された遺伝的多様性は特性の進化に影響するが,分子メカニズムは不明である.
- Sup35pの形状変種である酵母プリオン[PSI(+) は,保存されたタンパク質ベースの遺伝要素です.
- [PSI ((+)) ]は母から伝染し,細胞生存とフェノタイプ発現に影響を及ぼします.
研究 の 目的:
- イーストプリオン[PSI(+) が現象型可塑性および特性の進化に影響を与える分子機構を調査する.
- [PSI (((+)) ]媒介のナンセンスコードンの読み込みが観察された現象型多様性の基礎であるかどうかを判断する.
- [PSI(+) ]が複雑な特徴の獲得と安定化にどのように貢献するか探求する.
主な方法:
- [PSI (((+)) ]プリオンを含むおよびない酵母菌株の分析.
- 異なる遺伝的背景と成長条件におけるフェノタイプの多様性の検討.
- 無意味コドンの[PSI (((+)) ]依存の読み込みが分子メカニズムとしての調査.
主要な成果:
- すべてのテストされた特徴は,無意味なコドンの[PSI (((+)) ]媒介による読み込みと関連付けられました.
- 複合的で[PSI(+) ]に依存するフェノタイプは,遺伝的再分類によって[PSI(+) ]から独立した安定した特徴に頻繁に変換された.
- [PSI ((+)) ]は,様々な環境で一時的な生存上の利点をもたらします.
結論:
- 酵母プリオン [PSI(+) ]は,遺伝子型-フェノタイプ関係をグローバルに調節する表遺伝因子として作用します.
- [PSI(+) ]は,複雑な特性の迅速な獲得のためのメカニズムを提供し,それらの遺伝的同化を促進します.
- このエピジェネティックメカニズムは,現象性可塑性や進化経路の理解を新しい特徴に拡張します.
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