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Separation of Mouse Embryonic Facial Ectoderm and Mesenchyme
Published on: April 12, 2013
SIL遺伝子は,マウスの胚性軸向発達と左-右の仕様のために必要です
S Izraeli1, L A Lowe, V L Bertness
1Genetics Department, Medicine Branch, National Cancer Institute, NIH, Bethesda, Maryland 20889-5105, USA.
Nature
|June 29, 1999
まとめ
SIL遺伝子が欠けているマウスの胚は,ミッドラインの欠陥を示し,ソニック・ヘッジホッグ (Shh) 信号伝達を妨害し,ランダム化された心臓ループにつながります. これは,ミドルラインの破壊のタイミングと重度が,左から右のパターニングにどのように影響するかを強調しています.
科学分野:
- 発達生物学 発達生物学とは
- 胚形成とは,胚の形成である.
- 遺伝学 遺伝学とは
背景:
- 脊椎動物の胚の発達は,主体軸と左-右非対称性の確立に依存しています.
- ミッドラインの欠陥は,人間やモデル生物の左から右の異常と頻繁に関連しています.
- 異常な中線の発達における異なる横行性欠陥の分子的根拠は不明である.
研究 の 目的:
- 軸中線の発達と左から右のパターニングにおける早期応答遺伝子のSILの役割を調査する.
- 中線の欠陥と横行性の異常を結びつける分子メカニズムを解明する.
- ミドルライン障害の変動が胚のパターン形成にどのように影響するかを理解する.
主な方法:
- SIL遺伝子が欠けているマウスの胚を研究した.
- 軸中線の展開とソニック・ヘッジホッグ (Shh) 信号の分析.
- ノーダル,レフティ-2,Pitx2.2の心臓回路と発現パターンを評価した.
- 発見をSHミュータントの胚と比較した.
主要な成果:
- SILが欠けているマウスの胚は,軸中線の欠陥と中線のShh信号の障害を示した.
- SIL欠陥の胚は,ランダム化された心循環を示し,左から右に重度のパターンの欠陥を示した.
- Shh変異体との比較では,ミッドラインの欠陥が横行性に与える影響は,非対称的な遺伝子発現への障害のタイミングと重度に依存していることが明らかになった.
結論:
- 早期応答遺伝子のSILは,軸中線と正常なShh信号の確立に不可欠です.
- SIL欠乏によるミドルラインの発達障害は,左から右のパターニングに深刻な影響を及ぼします.
- 胚の左-右非対称性に対するミドルラインの欠陥の結果は,時間的動態と重要な発達信号伝達経路への障害の程度によって調節されます.
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