LRG1は,内皮TGF-βシグナリングを調節することにより,血管新生を促進します
Xiaomeng Wang1, Sabu Abraham1, Jenny A G McKenzie1
1Department of Cell Biology, UCL Institute of Ophthalmology, London EC1V 9EL, UK.
Nature
|July 23, 2013
まとめ
レウシンに富んだアルファ-2-グリコタンパク質1 (Lrg1) は,変形成長因子-β1 (TGF-β1) と相互作用することで,病的な血管新生を促進します. Lrg1を阻害すると,眼球血管新生が著しく低下し,新しい治療目標として明らかにされます.
科学分野:
- 分子生物学は分子生物学である.
- オフタルモロジック (眼科)
- 心血管生物学 心血管生物学
背景:
- 異常な新血管化は,癌,失明,動脈硬化などの重篤な疾患の根底にある.
- 病理的血管新生は,血管新生シグナリングの調節不良から生じるが,重要な調節因子は未だに特定されていない.
- これらのレギュレータを理解することは,効果的な疾患治療の開発に不可欠です.
研究 の 目的:
- 網膜の微小血管における病理的な血管新生の新しい調節体を特定する.
- アップレグレーテッド遺伝子であるルシンに富んだアルファ-2-グリコタンパク質1 (Lrg1) の機能とメカニズムを研究する.
主な方法:
- 網膜疾患のマウスモデルからの網膜マイクロ血管のトランスクリプトーム分析.
- LRG1が内皮細胞に及ぼすミトゲン効果を評価するためのインビトロアッセイ.
- Lrg1ノックアウトマウスとLRG1抗体阻害を用いたインビボ研究.
- 変換成長因子-β1 (TGF-β1) と下流の信号伝達経路とのLRG1の相互作用の分析.
主要な成果:
- レウシンに富んだアルファ-2-グリコプロテイン1 (Lrg1) は,病理的な網膜新血管化において上調された遺伝子として特定されました.
- LRG1は,TGF-β1と併用して,内皮細胞の増殖と血管新生を促進します.
- Lrg1欠乏は病的な眼球血管新生を減少させ,LRG1阻害は血管新生を弱めた.
- LRG1はエンドグリンに直接結合し,TGF-β1信号をプロ血管性Smad1/5/8経路に向けて調節する.
結論:
- レウシンに富んだアルファ-2-グリコプロテイン1 (Lrg1) は,血管新生の新しく重要な調節因子です.
- LRG1は,TGF-βシグナル伝達経路と相互作用することによって,そのプロ血管新生効果を媒介する.
- LRG1をターゲットにすることは,病理的な血管新生によって特徴づけられる疾患に対する潜在的な治療戦略を提供します.
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