の発達メカニズムは,初期の脊椎動物のミッドラインで進化した証拠です
Renata Freitas1, GuangJun Zhang, Martin J Cohn
1Department of Zoology, University of Florida, PO Box 118525, Gainesville, Florida 32611, USA.
Nature
|August 1, 2006
まとめ
脊椎動物のの進化は,異なる胚の起源にもかかわらず,共通の遺伝プログラムを使用しました. サメやランプリのミディアンフィンはソミットから発達し,ペア付属体より前の古代の発達メカニズムを明らかにしています.
科学分野:
- 進化的発達生物学 進化的発達生物学
- 比較ゲノミクスとは
- 脊椎動物の古生物学について
背景:
- ペアア付属体は,運動のための重要な脊椎動物のイノベーションです.
- 初期の脊椎動物は中間のを持っていたが,ペアリングしたがなかった.
- フィン開発のメカニズムは,ミッドラインの構造に起源があるかもしれない.
研究 の 目的:
- サメのミディアンフィン発達の遺伝的基礎を調査する.
- ミディアン・フィンとペアリング・フィンの開発メカニズムを比較する.
- の発達遺伝子の進化的起源を追跡する.
主な方法:
- サメのミディアンフィンの細胞タイプを特定するために分子マーカーを使用しました.
- HoxdおよびTbx18遺伝子の発現パターンを分析した.
- ランプレイのミディアンフィンへの拡張分析.
主要な成果:
- サメのミディアンフィン開発は,ペアリング付属体に似た遺伝プログラムを使用しています.
- 中間はソミティック・メソデルマから,ペアリングは横板メソデルマから生じる.
- HoxdとTbx18の遺伝子発現パターンは,中間翼に保存されています.
- ランプリのミディアンフィンもソミットから発達し,オートロゴス遺伝子を発現します.
結論:
- 共有された分子メカニズムがミディアンとペアリングフィン開発の基礎となっている.
- の発達は,初期の脊椎動物のソミティック・メソデルマに起源を持つ可能性が高い.
- 配列付属体は,これらの祖先のメカニズムの再展開によって進化した.
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