HoxA/HoxD遺伝子機能が欠けている哺乳類の四肢の早期発育停止
Marie Kmita1, Basile Tarchini, Jozsef Zàkàny
1Department of Zoology and Animal Biology and National Research Centre Frontiers in Genetics, University of Geneva, Sciences III, Quai Ernest Ansermet 30, 1211 Geneva 4, Switzerland.
Nature
|June 24, 2005
まとめ
脊椎動物のホックスAおよびホックスD遺伝子は,四肢の発達に不可欠です. マウスの前肢にこれらの遺伝子が欠けていると,深刻な発達停止と断絶を引き起こし,付属体の進化における彼らの役割を強調しました.
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
- 遺伝学 遺伝学とは
背景:
- 脊椎動物の HoxA と HoxD 遺伝子クラスターは,四肢の発達に不可欠です.
- 早期の致死率,補償,冗長性のために,それらの正確な機能を評価することは困難です.
研究 の 目的:
- 前肢の発達におけるHoxAおよびHoxD遺伝子の機能を,これらの四肢におけるHoxaおよびHoxd機能がすべて欠けているマウスを作ることによって調査する.
主な方法:
- HoxaとHoxdの機能を完全に失ったマウスの世代は,特に前肢で機能している.
- 変異体の前肢における発達パターンと四肢要素形成の分析.
主要な成果:
- HoxaとHoxd機能が欠けていた前肢は,初期の発達パターン停止を示した.
- 遠端の四肢要素の重度の断絶が観察され,これは部分的にソニック・ヘッジホッグのシグナル伝達の欠如によるものである.
- ミュータントの四肢は,先祖の幹の延長を想起させる特徴を示した.
結論:
- ホックス遺伝子の機能が付属体の発達に採用されることは,ヘッジホッグのシグナル伝達の開始に不可欠でした.
- この過程は,進化の過程でテトラポッドの付属体の遠端拡張を容易にした可能性が高い.
- この研究は,四肢の発達の進化的起源と,節足類のような構造との関連についての洞察を提供します.
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