カルシウム貯蔵センサーであるSTIM1は,OraiとCaV1.2チャネルを相互に制御しています
Youjun Wang1, Xiaoxiang Deng, Salvatore Mancarella
1Department of Biochemistry and Cardiovascular Research Center, Temple University School of Medicine, 3400 North Broad Street, Philadelphia, PA 19140, USA.
まとめ
ストロマル相互作用分子1 (STIM1) は,カルシウムチャネルを相互に制御する. STIM1の活性化により,電圧操作カルシウムチャネル (CaV1.2) が抑制され,貯蔵操作Oraiチャネルが活性化され,細胞カルシウムシグナル伝達に影響されます.
科学分野:
- 細胞生物学 細胞生物学
- 分子生理学 分子生理学
- イオンチャネル機能
背景:
- カルシウムの信号は細胞機能にとって極めて重要で,プラズマ膜の去極化と内部カルシウム貯蔵庫の枯渇によって調節される.
- 2つの主要なカルシウム入り経路,電圧操作カルシウム経路 (CaV1.2) と貯蔵操作オライ経路は,独立して機能すると考えられていた.
研究 の 目的:
- 電圧で作動するカルシウムチャネルと貯蔵で作動するカルシウムチャネルとの規制上の関連性を調査する.
- これらのカルシウムチャネル亜型間の相互作用を媒介するSTIMタンパク質の役割を明らかにする.
主な方法:
- ストア枯渇と突然変異によるSTIM1の活性化を調査した.
- 同局所化研究を用いて,CaV1.2チャネルとのSTIM1の相互作用を調べた.
- CaV1.2とOrai1の両方のチャネル活動にSTIM1の影響を評価しました.
主要な成果:
- STIM1の活性化は,CaV1.2チャネル活動を抑制し,Orai1チャネル活動を活性化します.
- 両方の規制行動は,STIM1.1.のSTIM-Orai活性化領域 (SOAR) によって仲介されています.
- STIM1は,CaV1.2とOrai1の両方のチャネルを含むER/プラズマ膜結合に局所する.
結論:
- STIM1は,CaV1.2とOrai1カルシウムチャネルの活動を調整する中央調節器として機能します.
- この相互制御メカニズムは,興奮しやすい細胞と興奮しない細胞の両方でカルシウム信号生成に重大な影響を及ぼします.
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