イノシトール三酸塩受容体の要求は,店内のCa2+チャネルを活性化するためです
H T Ma1, R L Patterson, D B van Rossum
1Department of Biochemistry and Molecular Biology, University of Maryland, School of Medicine, Baltimore, MD 21201, USA.
Science (New York, N.Y.)
|March 4, 2000
まとめ
イノシトール三酸塩受容体 (InsP3R) は,エンドプラズマ網膜 (ER) のカルシウム貯蔵庫をプラズマ膜のチャネルに接続することにより,カルシウムシグナル伝達に不可欠です. この研究は,InsP3Rを明確にします.
科学分野:
- 細胞生物学 細胞生物学
- 分子生理学 分子生理学
- カルシウムシグナル伝達
背景:
- エンドプラズマ網膜 (ER) のカルシウム貯蔵とプラズマ膜 (PM) の貯蔵操作チャネル (SOC) を結合するメカニズムは,カルシウムシグナル伝達に不可欠であるが,よく理解されていない.
- SOCは,TRPチャネルファミリーと潜在的に結びついているが,その正確な関係とアクティベーションメカニズムは不明である.
研究 の 目的:
- ER Ca2+貯蔵庫とPM SOCの結合メカニズムを調査する.
- 固有のSOCとTRP3チャネルの性質を比較し,その活性化要件を明らかにする.
- イノシトール三酸塩受容体 (InsP3Rs) がSOCとTRPのチャネル機能とER-PM結合における役割を決定する.
主な方法:
- ヒト胚性腎臓 (HEK293) 細胞における内生性SOCと安定的に発現するTRP3チャネルの比較.
- 凝縮された皮質F-actin.actin.inの存在下でのチャネル活性化の評価.
- 2-アミノエトキシジフェニルボラート (2-aminoethoxydiphenyl borate),細胞に浸透するInsP3R阻害剤を用いて,チャネル活動を阻害する.
主要な成果:
- TRP3チャネルは,SOCとは異なり,店舗独立であることが判明しました.
- 凝縮された皮質F-アクチンは,SOCとTRP3の両方のチャネルの活性化を阻害し,ER-PMの相互作用がカップリングに不可欠であることを示唆しました.
- 2-アミノエトキシジフェニルボラートによるInsP3R機能の抑制は,受容体誘発のTRP3活性化とストア誘発のSOC活性化の両方を阻害しました.
結論:
- InsP3Rは,SOCとTRPの両方のチャネルの開通を仲介する上で重要な役割を果たしています.
- イノシトール三酸塩受容体は,ER貯蔵庫の枯渇とSOCの活性化との間の生理学的結合を維持するために不可欠です.
- InsP3Rsによって媒介されるER-PM相互作用は,カルシウムシグナル伝達におけるSOCとTRPチャネルの機能に不可欠である.
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Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
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