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Updated: May 14, 2026
08:02
Dissection and Flat-mounting of the Threespine Stickleback Branchial Skeleton
Published on: May 7, 2016
軟骨魚のの発達と脊椎動物の四肢の起源
Mikiko Tanaka1, Andrea Münsterberg, W Gary Anderson
1Division of Cell and Developmental Biology, Wellcome Trust Biocentre, University of Dundee, Dow Street, Dundee DD1 5EH, UK. mtanaka@dundee.ac.uk
Nature
|April 5, 2002
まとめ
翼からテトラポッドの四肢の進化は,ドッグフィッシュの胚で調査されています. 遺伝子発現は,四肢のアイデンティティが早期に進化したことを示唆しますが,Shh遺伝子は早期に進化しました.
科学分野:
- 進化的発達生物学 進化的発達生物学
- 比較胚生物学について
- パレオントロジー・パレオントロジー
背景:
- 横側の折り畳み理論は,四足類の四肢が,細分されたから進化したことを示唆している.
- 初期の四肢の進化を理解するには,原始的な脊椎動物を研究する必要があります.
研究 の 目的:
- ドッグフィッシュ (Scyliorhinus canicula) の胚におけるの発達を調査する.
- 原始的な軟骨魚の四肢発達に関連する遺伝子発現を調べる.
主な方法:
- ドッグフィッシュの胚のスキャン電子顕微鏡.
- Engrailed-1,Tbx4,Tbx5,dHand.の遺伝子発現分析について
主要な成果:
- ドッグフィッシュの胚では,脇翼の折りたたみが見つかりませんでした.
- Engrailed-1表現は,身体の区画化を示しています.
- Tbx4およびTbx5遺伝子は,より高い脊椎動物と同様に,四肢のアイデンティティを指定します.
- Shhの文字は欠けていたが,dHandは finn-budsで表現されていた.
- 犬魚の軸は,体軸に平行しています.
結論:
- 肢体同一性遺伝子 (Tbx4,Tbx5) は,脊椎動物の進化の初期に保存されています.
- ドッグフィッシュにおけるShhの欠如は,テトラポッドの四肢進化の過程で,身体軸から羽根を解放する上で重要な役割を果たすことを示唆しています.
- Shhは,おそらく別々の四肢軸を確立する上で重要な役割を果たした.
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