代謝系におけるエクサプテーションによる進化的イノベーションの潜在的能力である
1Institute of Evolutionary Biology and Environmental Sciences, Building Y27, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
Nature
|July 16, 2013
まとめ
代謝の特徴のような多くの進化的革新は,適応不可能なエクサプテーションとして生じることがあります. この研究は,代謝ネットワークの適応がしばしば複数の意図しない機能を提供することを明らかにし,これまで考えられていたよりも多くの非適応的起源を示唆しています.
科学分野:
- 進化生物学の進化生物学について
- メタボリックネットワークとは
- バイオケミストリー バイオケミストリー
背景:
- 進化的革新は,エクサプテーション (他の特性の副産物) として,適応性のない形で発生することがあります.
- 例としては,飛行前の羽と,酵素として発生したレンズの結晶が含まれます.
- 適応性特性の非適応的起源の頻度は極めて重要だが,研究するのは難しい.
研究 の 目的:
- 代謝システムにおける非適応的起源の流行を調査する.
- 単一の炭素源からバイオマスを合成する代謝ネットワークの能力を分析する.
- 進化生物学における代謝におけるエクサプテーションの影響を調査する.
主な方法:
- 生命を維持できるランダムな代謝ネットワークの計算式サンプリング.
- ネットワークの可動性を様々な炭素源で分析する.
- 生物化学反応をモデル化するために新しい計算手法を使用.
主要な成果:
- 一つの炭素源で生存可能である代謝ネットワークは,多くの場合,他の多くのものに生存可能性を示します.
- メタボリックシステムの適応は,多くの場合,複数の潜在的エクサプテーションをもたらします.
- 例えば,グルコースによる生存能力は,さらに最大44の炭素源に生存能力を授けることができる.
結論:
- 代謝システムは,適応性のない起源を持つ進化的革新のための固有の潜在能力を有しています.
- 代謝特性の有意な数は,適応的でない起源を持つ可能性があります.
- 代謝における適応性と非適応性の特徴を区別することは,難しい課題です.
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