マウスにおけるインスリンシグナル伝達の代替経路で,IRS-1遺伝子の標的を絞った中断を伴う
E Araki1, M A Lipes, M E Patti
1Research Division, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215.
Nature
|November 10, 1994
まとめ
インスリン受容体基板-1 (IRS-1) が欠けていたマウスは,成長障害とグルコース耐性を示した. この研究は,インスリン/IGF-1シグナル伝達におけるIRS-1-依存および独立経路を明らかにしています.
科学分野:
- セルラー・シグナリング
- 分子生物学は分子生物学である.
- エンドクリノロジー エンドクリノロジー
背景:
- インスリン受容体基板-1 (IRS-1) は,インスリンとIGF-1受容体のシグナル伝達における重要なタンパク質です.
- IRS-1の活性化にはチロシンリン酸化があり,PI(3) Kの結合と活性化につながります.
- IRS-1の役割を理解することは,代謝および成長因子研究にとって極めて重要です.
研究 の 目的:
- インスリンとIGF-1シグナル伝達経路におけるIRS-1の特定の役割を調査する.
- IRS-1欠乏症の生理学的結果を決定する.
- インスリン/IGF-1の作用に関与する代替基質を特定する.
主な方法:
- 標的遺伝子変異を用いたIRS-1欠乏マウスの生成.
- ノックアウトマウスにおけるIRS-1リン酸化とPI(3) Kの活性に関する分析.
- 子宮内成長,グルコース耐性,およびグルコース吸収の評価 in vivo および in vitro.
主要な成果:
- IRS-1欠乏したマウスは,子宮内成長が著しく低下 (50%) し,グルコース耐性が低下した.
- インスリン/IGF-1刺激によるグルコース摂取量の有意な減少が観察されました.
- IRS-2という新しいチロシンリン酸化タンパク質は,IRS-1とは異なる代替基板として特定されました.
結論:
- この研究は,インスリンとIGF-1のためのIRS-1-依存およびIRS-1-独立のシグナル伝達経路の両方に証拠を提供します.
- IRS-1欠乏症は,重要な代謝および成長関連の欠陥につながる.
- IRS-2の発見は,インスリン/IGF-1受容体のシグナル伝達の複雑さを強調し,新しいプレーヤーを特定します.
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