昆虫の形態学的多様化は,翼のシリアルホモローグの改変によるものである
Takahiro Ohde1, Toshinobu Yaginuma, Teruyuki Niimi
1Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya, Japan.
まとめ
昆虫の進化は,腹部セグメントの翼のような構造が,失われたのではなく,修正された可能性があることを示しています. 研究者らは,ミールワームの甲虫の同類構造を特定し,昆虫の体型多様化における重要な遺伝子の役割を明らかにした.
科学分野:
- 発達生物学 発達生物学とは
- 進化生物学の進化生物学について
- エントモロジー エントモロジー学
背景:
- 3億年前の化石昆虫は,胸部と腹部部に翼のようなパッドを展示しており,シリアルホモロジーを示唆しています.
- 翼のないセグメントにおけるこれらの翼状構造の進化的運命 (損失対改変) は,依然として開かれた問題である.
研究 の 目的:
- 既存の昆虫の非翼のセグメントの翼の連続同類を識別するために.
- これらの同質構造の発達を支える遺伝的メカニズムを調査する.
主な方法:
- 粉虫虫虫 (Tenebrio molitor) の同類構造の特定,特にヒポメロンと幼虫の歯茎の成長.
- Hox RNAの干渉を用いた実験操作により,これらのドメインが翼のような構造に変換される.
- キーウィングセレクター遺伝子の遺伝子発現と機能的分析 (残骸型および型).
主要な成果:
- ヒポメロン (第1胸部セグメントの腹側側部分) と幼虫の背側側歯茎の成長は,翼のシリアルホモログとして識別されました.
- ホックスRNAの干渉は,これらの識別されたドメインから翼のような構造の発達を誘導した.
- 翼選択遺伝子の"残骸"と""は,これらの同類構造の形成において重要な役割を果たします.
結論:
- 背部の付属体の完全な喪失ではなく,背部の付属体の修正が,昆虫の体型多様化の重要なメカニズムとして提案されています.
- この研究は,昆虫の付属体の進化的可塑性,および形態学的イノベーションの遺伝的基礎についての洞察を提供します.
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