ホックスタンパク質の変異と昆虫のボディプランのマクロ進化
Matthew Ronshaugen1, Nadine McGinnis, William McGinnis
1Section of Cell and Developmental Biology, Universith of California--San Diego, Jolla, CA 92093, USA.
Nature
|February 23, 2002
まとめ
Ultrabithorax (Ubx) タンパク質の進化的変化は,六足の昆虫の体プランの発達と関連しています. この分子変化が,多肢の祖先から現代の昆虫への移行を説明している.
科学分野:
- 進化的発達生物学 進化的発達生物学
- 分子進化は分子進化である.
- 節足類の進化について
背景:
- ホメオティック (ホックス) 遺伝子は,動物の発達と形態学的進化に不可欠です.
- 昆虫の進化には,多肢の祖先から六足の形への大きな移行が伴いました.
- Ultrabithorax (Ubx) や腹部A (AbdA) のようなホックスタンパク質は,セグメントのアイデンティティと付属体の発達に役割を果たします.
研究 の 目的:
- ヘクサポッド (六足) の四肢パターンへの進化的移行の基礎となる分子機構を調査する.
- ホックスタンパク質の機能の変化が,甲殻類のような祖先から昆虫の分岐に寄与したかどうかを判断する.
主な方法:
- 昆虫と甲殻類におけるUbx/AbdAタンパク質発現と機能の比較分析.
- Ubxタンパク質の機能における自然に選択された変化の役割を調査する.
主要な成果:
- 昆虫のUbx/AbdAタンパク質は,腹部セグメントにおける胸の足の発達を抑制する.
- 対照的に,甲殻類のUbx/AbdAタンパク質は,Limb primordiaで発現するが,肢の発達を抑制しない.
- Ubxタンパク質の自然に選択された変化は,六足の四肢パターンへの進化的シフトと関連しています.
結論:
- ホックスタンパク質,特にUbxの機能的性質の変化は,マクロ進化の形態学的変化を誘発する合理的なメカニズムである.
- この研究は,Ubxにおける特定の分子変化と,昆虫の6本足の体型の進化的起源を結びつける証拠を提供します.
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