TRICチャネルは,細胞内貯蔵中のCa2+の取り扱いに不可欠です
Masayuki Yazawa1, Christopher Ferrante, Jue Feng
1Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
Nature
|July 6, 2007
まとめ
研究者らは,細胞内のカルシウム (Ca2+) の放出をバランスするのに不可欠なTRICチャネルを特定しました. これらのカチオンチャネルは,適切な細胞シグナル伝達と心不全の予防に不可欠です.
科学分野:
- 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:
- 細胞シグナリングは,細胞内貯蔵物から正確なカルシウム (Ca2+) の放出に依存しています.
- Ca2+の放出を均衡させるためのイオンの対抗運動は,分子的に特徴づけられていないままである.
- Ca2+放出チャネルは15年以上前に特定されましたが,関連する反イオンチャネルは不明です.
研究 の 目的:
- 細胞内Ca2+シグナル伝達に関与する推定対離子チャネルの分子同一性を特定する.
- 新しく特定されたTRICチャネルサブタイプの構造と機能を特徴付ける.
主な方法:
- TRICチャンネルサブタイプのクローン化と特徴付け.
- 浄化されたTRICチャネル製剤の電気生理学的測定.
- 心臓と骨格筋の機能に関するTRICノックアウトマウスモデルの分析.
主要な成果:
- 2つのTRIC (トリメリック細胞内カチオン) チャンネルサブタイプが特定され,細胞内貯蔵物に発現しました.
- TRICチャネルは,三つのトランスメブランセグメントを持つホモトライマーを形成し,単価カチオン選択性を示す.
- TRIC-ノックアウトマウスは,胚性心不全と骨格筋のサルコプラズマ性網膜機能不全を示し,K+の透過性が低下し,Ca2+シグナル伝達が変化した.
結論:
- TRICチャネルは,重要な対離子チャネルとして機能し,細胞内貯蔵物からCa2+の放出と同期します.
- TRICチャネルは,細胞のCa2+ホメオスタシスを維持し,心臓機能不全を予防するために重要です.
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