TMEM16FはCa2+活性化カチオンチャネルを形成し,血液凝固の際に血小板内の脂質の乱交に必要なものです
Huanghe Yang1, Andrew Kim, Tovo David
1Department of Physiology, Howard Hughes Medical Institute, University of California, San Francisco, 94143, USA.
Cell
|October 2, 2012
まとめ
TMEM16Fタンパク質は,血の凝固に不可欠であり,血小板内の脂質の乱交に不可欠なカルシウム活性化イオンチャネルとして作用します. その機能障害は出血障害を引き起こし,血栓形成に影響を及ぼし,心臓血管の健康におけるその役割を強調する.
科学分野:
- 分子生物学は分子生物学である.
- バイオフィジックス 生物物理学
- 血液学 ヘマトロジ
背景:
- 膜脂質非対称性は,血液凝固に不可欠である.
- TMEM16F欠乏症は,スコット症候群と,カルシウム依存性脂質混ざり障害と関連しています.
- TMEM16ファミリータンパク質には,カルシウム活性化塩化物チャネル (CaCC) が含まれています.
研究 の 目的:
- 血液凝固と血小板機能におけるTMEM16Fの役割を調査する.
- TMEM16Fのイオンチャネル活動を特徴付けるために.
- TMEM16Fチャネル選択性の分子決定因子を特定する.
主な方法:
- TMEM16Fノックアウトマウスの生成と分析.
- 出血不全と動脈血栓形成モデルの評価.
- ヘテロロジ的に表現されたTMEM16F.の電気生理学的記録.
- サイト・ディレクテッド・ミュータゲネシスによる探査チャネル機能.
主要な成果:
- TMEM16Fのノックアウトマウスは出血不全と動脈栓塞に対する保護を示した.
- ノックアウトマウスからの血小板は,カルシウム依存のフォスファディチルセリンの露出とプロコアグラント活性が不足していることを示しています.
- TMEM16Fの異質表現は,CaCCではなく,小導電性,カルシウム活性化非選択性カチオン (SCAN) 電流を生成する.
- TMEM16F-SCANチャネルは,Ca(2+を含むカチオンに浸透し,カルシウムと電圧によってゲートされます.
- TMEM16FとTMEM16Aチャネルに対するカチオン対アニオン選択性には,特定の毛孔残留物が影響する.
結論:
- TMEM16Fは,血液凝固中の血小板スクランブラーゼ活性に不可欠なカルシウム活性化カチオンチャンネルとして機能します.
- TMEM16Fは,膜脂質非対称性および血小板における血栓形成作用の維持に不可欠である.
- TMEM16Fチャネル特性を理解することで,スコット症候群と凝固障害の洞察が得られます.
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