相互接続された信号フィードバックループの自己調節システムは,マウスの肢体のパターンを制御します
Jean-Denis Bénazet1, Mirko Bischofberger, Eva Tiecke
1Developmental Genetics, Department of Biomedicine, University of Basel, Mattenstrasse 28, CH-4058 Basel, Switzerland.
Science (New York, N.Y.)
|February 21, 2009
まとめ
ソニック・ヘッジホッグ (SHH) とフィブロブラスト成長因子 (FGF) のシグナル伝達経路は,四肢の発達を調節する. 骨形態遺伝タンパク質4 (BMP4) は信号を発信し,SHH は Gremlin1 (GREM1) を介して伝播し,指の形成を制御する.
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
- システム生物学 システム生物学
背景:
- 胚形成は,空間的に異なるセンター間の複雑なシグナル伝達に依存しています.
- 肢体の発達には,表皮細胞-メゼンキマ (e-m) のフィードバックループが関与し,特にソニック・ヘッジホッグ (SHH),繊維細胞成長因子 (FGF),および骨形態遺伝タンパク質 (BMP) のシグナル伝達が関与しています.
- これらのフィードバックループを媒介するGremlin1 (GREM1) の役割は極めて重要ですが,完全に解明されていません.
研究 の 目的:
- 肢体の発達におけるe-mフィードバックループの規制メカニズムを解明する.
- デジタル仕様制御におけるBMP4,SHH,GREM1の相互作用を理解する.
- これらのシグナル伝達経路が,強固な肢体の発達のための自己調節ネットワークを形成する方法を調査する.
主な方法:
- ネズミの分子遺伝学を使って,遺伝子調節を研究した.
- 信号ダイナミクスを分析するために数学的モデリングを使用した.
- Grem1.の異なった転写調節を調査した.
主要な成果:
- BMP4シグナリングはe-mフィードバックを開始し,その後SHH.によって伝播されます.
- スイッチメカニズムは,高速のBMP4/GREM1モジュールを,より遅いSHH/GREM1/FGFループに接続します.
- この相互接続されたネットワークは,遠端の肢体の発達の堅固な調節を保証し,多様性を容認します.
結論:
- この研究は,BMP4とSHHを含む,四肢発達における新しい調節スイッチを明らかにしています.
- 自己規制の信号ネットワークは,数字の仕様を正確に制御することを保証します.
- 信号伝達経路の相互接続は,四肢の発達における回復力と適応力を提供します.
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