牛に関連する亜鉛指遺伝子による脊椎動物の左右非対称性の制御
A Isaac1, M G Sargent, J Cooke
1National Institute for Medical Research, Mill Hill, London NW7 1AA, UK.
まとめ
チークの胚心臓の発達は,スナイルファミリーの遺伝子cSnRに依存しています. cSnRの機能や重要なシグナル伝達タンパク質を妨害すると,心臓のループの方向と胚の回転が変化し,cSnRが明らかになる.
科学分野:
- 発達生物学 発達生物学とは
- 分子遺伝学 分子遺伝学
- 胚学 胚学について
背景:
- 正常なチキの発達には,特に心臓のループと胚のトルションにおいて,正確な左-右非対称性が含まれています.
- スナイル族の亜鉛指タンパク質 (cSnR) は,横側メソデルマで発現することが知られている.
- 細胞間信号伝達経路は,左-右の体軸の決定を確立するために不可欠です.
研究 の 目的:
- 雛の発達中の心臓回路の方向と胚の回転を制御する cSnR 遺伝子の役割を調査する.
- cSnR機能と既定の左右シグナル伝達経路の関係を決定する.
主な方法:
- 心臓形成に先立つ cSnR 遺伝子機能を阻害するために,アンチセンセスの破壊を活用しました.
- 左から右の軸の決定に関与する細胞間信号タンパク質の子宮外源を導入した.
- 心循環の方向と胚の回転の方向を観察し,分析した.
- 信号タンパク質操作に対する反応としてcSnR発現の非対称性を評価した.
主要な成果:
- cSnR機能のアンチセンセスの障害は,心臓のループの方向と,その後の胚のトルションをランダムに決定した.
- 子宮外シグナル伝達タンパク質は,心臓発達の手性を変え,cSnR発現アシンメトリーに影響を与えました.
- cSnRは,解剖学的非対称性を制御するために,ノダルシグナル伝達と下流または並行して機能しているようです.
結論:
- cSnR遺伝子は,雛の心臓発達の解剖学的非対称性と胚の歪みを調節する上で重要な役割を果たします.
- cSnRは,左から右のボディ軸を確立するシグナルカスケードの重要な媒介者として作用し,ノダルに下流または平行に作用します.
- cSnRの機能を理解することで,オルガノゲネシスとボディプランの確立の基礎となる分子機構の洞察が得られます.
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