昆虫のホックスタンパク質における転写抑制ドメインの進化

Ron Galant¹, Sean B Carroll

¹Howard Hughes Medical Institute, University of Wisconsin, Madison 53706, USA.

Nature

|February 23, 2002

まとめ

ホメオティック (ホックス) 遺伝子は,動物の体プランを調節する. Ultrabithorax (Ubx) タンパク質に新たに特定された抑制ドメインは,昆虫の多様性の進化を説明する可能性がある.

科学分野:

発達生物学発達生物学について
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:

ホメオティック (ホックス) 遺伝子は,動物体の地域化に極めて重要です.
ホックス遺伝子の進化は,重複,分岐,および規制の変化を含む動物多様性に貢献します.
ホックスタンパク質が進化の過程で新しいタンパク質の活性化を得る方法は,未だにほとんど未探究のままである.

研究の目的:

ホックスタンパク質が進化の過程で新しい機能を獲得したかどうかを調査する.
ホックスタンパク質の新機能ドメインを特定し,その進化的保存を評価する.
動物形態学の多様化におけるこれらのドメインの潜在的な役割を探求する.

主な方法:

ドロソフィラ・ウルトラビトラックス (Ubx) タンパク質内の機能ドメインの識別と特徴付け.
異なる節足類およびオニコフォラン系におけるUbxのオースロロジーの比較シーケンス分析.
識別されたドメインの活動を決定するための機能分析.

主要な成果:

転写抑制ドメインは,Drosophila Ubx.のカルボキシ末端領域で特定されました.
この抑圧領域は,他の昆虫のUbxのオートログに保存されています.
このドメインは,昆虫以外の節足類やオニコフォランスのUbxタンパク質に含まれていません.

結論:

Ubxにおけるカルボキシ末端抑制ドメインの進化は,昆虫のより大きな形態学的多様化を可能にしたのかもしれない.
この発見は,遺伝子調節の変化を超えて,ホックスタンパク質の機能の変化が,進化の多様化に寄与することを示唆しています.
この研究は,動物の多様性を理解するために,タンパク質レベルの進化を探求することの重要性を強調しています.

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