モジュール式増強剤の段階的な改変が,ドロソフィラ菌の集団における適応の基礎となっている
Mark Rebeiz1, John E Pool, Victoria A Kassner
1Howard Hughes Medical Institute and Laboratory of Molecular Biology, University of Wisconsin, Madison, WI 53706, USA.
Science (New York, N.Y.)
|December 19, 2009
まとめ
動物の特徴の進化には,強化剤と呼ばれるシス調節要素の変化が伴う. この研究は,増強剤の複数の変異が,ドロソフィラハエの重要な適応特性をどのように生み出したかを明らかにしています.
科学分野:
- 進化生物学の進化生物学について
- 発達遺伝学 発達遺伝学
- 分子進化は分子進化である.
背景:
- 動物の形態学の進化は,発達的に調節された遺伝子を制御するシス調節要素 (強化剤) の変化によって著しく影響を受けています.
- 変異の数,起源,効果,順序を含む特定の変異経路は,変化した強化剤の機能につながる,大部分は未知のままです.
研究 の 目的:
- 増強剤の進化の変異経路を解明する.
- ウガンダのドロソフィラ群の適応性メラニズム遺伝的基礎を,エボニーロカス増強剤を分析することによって調査する.
主な方法:
- エボニーロクスのモジュラー強化器内の一連の置換の局所化.
- 現象型変化に寄与する突然変異の起源,効果,および組み合わせの分析.
主要な成果:
- エボニー強化剤の最近の少なくとも5つの変異を特定しました.
- これらの突然変異は,定常変異と新しい突然変異の両方から生じた.
- これらの突然変異の共同効果は,重要な現象型変化をもたらし,適応性メラニズムに寄与しました.
結論:
- 強化剤は,タンパク質配列と比較して異なる機能的制約を持つ独特のマクロ分子実体です.
- さまざまな源から発生する複数の変異は,急速に結合して,大きな現象型効果を持つアレルを作り,適応的進化を促すことができます.
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