タンパク質キナーゼAは,近接管の内細胞小胞の塩素伝導性を調節する
1Department of Medicine, University of California, San Francisco 94143-0532.
Nature
|December 13, 1990
まとめ
腎臓内細胞胞の塩化物輸送は,循環型AMP依存タンパク質キナーゼAによって調節される. このリン酸化は,塩化物導電性を活性化させ,エンドソームのpHを制御するメカニズムを示唆する.
科学分野:
- 細胞生物学 細胞生物学
- 分子生理学 分子生理学
- 腎臓生理学 腎臓生理学
背景:
- リン酸化によるイオン輸送の調節は,細胞のプラズマ膜で知られている.
- 細胞内膜のトランスポーター調節におけるセカンドメッセンジャーの役割は,ほとんど未知のままである.
研究 の 目的:
- 酸化によって,内細胞胞体内の塩化物輸送が調節されているかどうかを調査する.
- タンパク質キナーゼAがこれらの小胞の塩素伝導性に影響するかどうかを判断する.
主な方法:
- ウサギの近接管から内細胞性水泡を分離した.
- 塩素輸送は,塩素に敏感な光インジケーターを使用して測定されました.
- 膀は,陽子ポンプの活動と塩化物の伝導性を分析した.
主要な成果:
- 細胞内小胞は,内部へ向ける陽子ポンプと塩化物導電性を有する.
- 塩素伝導性は,周期的なAMP依存タンパク質キナーゼA (PKA) によって活性化されました.
- イオン結合塩化物輸送の証拠は見つかりませんでした.
結論:
- PKAによるリン酸化は,内細胞胞体における塩素伝導性を調節する.
- この規則は,スティルベンに敏感な塩化物トランスポーターを通じて,エンドソームのpHを制御するメカニズムを提供します.
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