電圧依存型リン酸化は,クロマフィン細胞のCa2+電流促進を誘発する可能性があります

C R Artalejo¹, S Rossie, R L Perlman

¹Department of Pharmacological and Physiological Sciences, University of Chicago, Illinois 60637.

Nature

|July 2, 1992

まとめ

牛のクロマフィン細胞は,2つのCa2+電流を示します. 電圧依存型リン酸化は,促進Ca2+電流の徴用を調節し,イオンチャネル調節を理解するための重要な発見である.

科学分野:

神経科学は神経科学である.
細胞生物学細胞生物学
イオンチャンネル生理学イオンチャンネル生理学

背景:

牛のクロマフィン細胞は,標準成分と促進成分のCa2+電流を特徴として持っています.
促進Ca2+電流は通常静止状態ですが,特定の脱極化パターンによって活性化することができます.
タンパク質キナーゼAの活性化は,Ca2+電流促進におけるリン酸化の役割を示唆しています.

研究の目的:

促進Ca2+電流を募集する際にタンパク質リン酸化が果たす役割を調査する.
これらの電流の電圧依存的徴用の背後にあるメカニズムを解明する.

主な方法:

使用した牛のクロマフィン細胞です.
Ca2+の電流徴集を研究するために,プリパルスと反復デポラライゼーションを適用しました.
タンパク質リン酸化阻害剤とフォスファターゼ2A注射の効果を調査した.
異なる条件下での採用の可逆性を調べました.

主要な成果:

脱極化によって誘発されるCa2+流の誘導は,急激でファーストオーダーのプロセスである.
タンパク質リン酸化阻害剤とフォスファタゼ2Aの抑制された募集.
通常は逆戻り可能な電圧依存リクルートメントは,フォスファターゼ阻害剤で不可逆的になりました.

結論:

Ca2+チャネルまたは関連するタンパク質の電圧依存型リン酸化は,Ca2+電流の誘導を媒介する.
このリン酸化機構により,膜ポテンシャルがイオンチャネル活動を調節することができます.

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