STIM2はフィードバックレギュラーであり,基礎細胞溶液とエンドプラズマ網膜のCa2+レベルを安定させます
Onn Brandman1, Jen Liou, Wei Sun Park
1Department of Chemical and Systems Biology, Bio-X/Clark Center W200, Stanford University, Stanford, CA 94305, USA. onn@stanford.edu
Cell
|December 28, 2007
まとめ
STIM2は,Orai1チャネルを活性化することによって,基礎カルシウム (Ca2+) レベルを調節する. この発見は,細胞カルシウムホメオスタシスと機能を維持するために重要なフィードバックメカニズムを特定しています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 生理学 生理学とは
背景:
- 基礎カルシウム (Ca2+) 濃度は,細胞のシグナル伝達と機能に極めて重要です.
- 基礎Ca2+の調節不良は,様々な疾患に起因しています.
- 基礎Ca2+ホメオスタシスを制御するメカニズムは,依然としてほとんど不明です.
研究 の 目的:
- 基礎細胞溶液Ca2+濃度の新しい調節体を特定する.
- Ca2+ホメオスタシスの維持におけるSTIM2の役割を明らかにする.
主な方法:
- 人間のシグナル伝達タンパク質のsiRNAスクリーンを実施しました.
- Ca2+流入におけるSTIM2の機能を調査した.
- Ca2+イメージング技術を使用しました.
主要な成果:
- 基礎Ca2+濃度の強力な陽性調節剤としてSTIM2を特定しました.
- STIM2は,小規模なER Ca2+貯蔵庫の枯渇時に,Orai1チャネルを通じたCa2+の流れを活性化します.
- Ca2+ホメオスタシスのフィードバックモジュールにおけるSTIM2の役割を実証した.
結論:
- STIM2は,基礎Ca2+レベルを維持する上で重要な役割を果たします.
- STIM2は,ER Ca2+の貯蔵状態を感知する上で,STIM1とは異なる機能を持っています.
- STIM2は,細胞内Ca2+濃度を調節するフィードバックシステムの中心にある.
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