カルシウム電流の阻害を誘発する特定の受容体にGタンパク質サブタイプの割り当て
C Kleuss1, J Hescheler, C Ewel
1Institut für Molekularbiologie und Biochemie, Freie Universität Berlin, Germany.
Nature
|September 5, 1991
まとめ
研究者らは,分泌細胞内のカルシウムチャネルを阻害する特定のGタンパク質サブタイプ (Go1とGo2) を特定しました. この発見は,ムスカリニンおよびソマトスタチン受容体が細胞の反応をどのように調節するかを明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- 神経薬理学神経薬理学について
- 分子生理学 分子生理学
背景:
- プラズマ膜受容体は,分泌細胞の電圧に依存するCa2+チャネルを阻害する.
- この抑制は, pertussis toxin-sensitive Gタンパク質によって媒介される.
- 異なるGタンパク質αサブユニットが存在するが,受容体媒介阻害におけるそれらの特定の役割は不明である.
研究 の 目的:
- 特定のGタンパク質サブタイプが,特定のプラズマ膜受容体によるCa2+チャネル阻害を媒介するかを決定する.
- pituitary細胞における受容体調節カルシウムシグナル伝達の基礎となる分子機構を解明する.
主な方法:
- 反感覚オリゴヌクレオチドの核内注射をネズミの pituitary GH3細胞にします.
- 特定のGタンパク質サブタイプを選択的に標的にし,抑制するためにアンチセンセスの技術を活用しました.
- 電圧に依存するCa2+チャネル活動に対する機能的影響を測定した.
主要な成果:
- Ca2+チャネル阻害におけるGo型Gタンパク質の重要な役割を確立した.
- Go1サブタイプが,マスカリン受容体を通して抑制を媒介することを実証した.
- Go2亜型がソマトスタチン受容体を通して抑制を媒介することを示した.
結論:
- Go型Gタンパク質のGo1およびGo2サブタイプは,それぞれマスカリンおよびソマトスタチン受容体によるCa2+チャネル阻害を差異的に媒介する.
- Gタンパク質結合受容体のシグナル伝達経路の詳細な分子理解を提供します.
- 分泌細胞におけるカルシウムホメオスタシスの調節に関する知識を深める.
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