ホックス遺伝子と昆虫と甲殻類の多様化は,体計画である
Nature
|August 3, 1995
まとめ
アルテミア (甲殻類) のホックス遺伝子は,これらの遺伝子が異なるセグメントを指定する昆虫とは異なり,胸部で重複表現を示す. これは,幹のセグメンテーションとホックス遺伝子の機能多様化の独立した進化を示唆しています.
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
- 遺伝学 遺伝学とは
背景:
- 甲殻類と昆虫は,分割された体プランを共有しているが,トランクセグメントの専門化の独立した進化を示している.
- ホックス遺伝子は,様々な動物群の身体軸のパターンとセグメントのアイデンティティを理解するために重要な保存された遺伝マーカーです.
研究 の 目的:
- ブランキオポッドの甲殻類アルテミア・フランシスカナ (Artemia franciscana) の4つのホックス遺伝子の発現パターンを調査するために.
- これらのパターンを,昆虫の既知のホックス遺伝子発現と比較して,体構造と遺伝子機能の進化的変化を推論する.
主な方法:
- ホックス遺伝子発現の比較分析.
- アルテミア・フランシスカナ菌における4つの特定のホックス遺伝子 (Antp, Ubx, abdA) の検査.
- Artemia Hox遺伝子発現ドメインと昆虫の遺伝子発現ドメインの比較.
主要な成果:
- アルテミアでは,幹ホックス遺伝子のAntp,Ubx,abdAが,均一な胸部領域内の表現ドメインを大きく重複していることを示している.
- 対照的に,これらの同じホックス遺伝子は,昆虫の胸部と腹部の異なるセグメントタイプを指定します.
- これらの発見は,ホックス遺伝子の機能的多様化のための多段階のプロセスを示唆しています.
結論:
- ホックス遺伝子の機能の進化は,組織特異性の初期の違いと,後のセグメンタル差異の定義における役割の獲得を伴う.
- ブランキオポッドの胸部は,昆虫の幹の全生前 (胸部と腹部) 領域に進化的に同型である可能性があります.
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