謎めいた遺伝的変異は,RNA酵素の急速な進化的適応を促進する
Eric J Hayden1, Evandro Ferrada, Andreas Wagner
1Institute of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland.
Nature
|June 4, 2011
まとめ
環境の変化まで隠された神秘的な遺伝的変異は,進化的適応を加速する. この変異を有するRNA酵素集団は,新しい基板により早く適応し,事前に適応した遺伝子型を明らかにした.
科学分野:
- 進化生物学の進化生物学について
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- 暗号的変異は,表型的強度から突然変異に起因する.
- この隠された変異は,環境的または遺伝的変化によって進化に影響を与えることができます.
- 適応を促進する役割,特に複雑な生物において,まだ十分に研究されていない.
研究 の 目的:
- 進化的適応の加速における神秘的な遺伝的多様性の役割を調査する.
- 暗号的変異が,新しい環境において有益な,事前に適応した遺伝子型を含むことができるということを示すために.
主な方法:
- RNA酵素の集団の進化,蓄積された暗号的変異があるか,ないか.
- 適応率を評価するために,新しい基板で集団を挑戦する.
- ゲノタイプ空間における進化したRNA集団を分析して,多様性の動態を理解する.
主要な成果:
- 暗号的変異を持つ集団は,新しい基板に著しく早く適応した.
- 詳細なゲノタイプ分析により,暗号的変異によって促進された新しい適応性ゲノタイプの探索が明らかになりました.
- 暗号的変異は,変化した環境で有利になる,事前に適応した遺伝子型を提供した.
結論:
- 謎めいた遺伝的多様性は,有益な遺伝子型の探査を可能にすることで,適応的進化において肯定的な役割を果たします.
- 謎めいた多様性につながるフェノタイプの強さは,迅速な適応を図るため,集団を原動力にすることができます.
- エピスタシスと頑丈さは,暗号的変異を通じて進化的適応を容易にする重要な要因です.
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