TREK-1とBest1のチャネルは,GPCRの活性化時に,アストロサイトにおけるグルタミン酸の高速と遅い放出を媒介する
Dong Ho Woo1, Kyung-Seok Han, Jae Wan Shim
1Center for Neural Science, Korea Institute of Science and Technology, Seoul, Republic of Korea.
Cell
|October 2, 2012
まとめ
アストロサイトはグルタミン酸を2つの異なる経路で放出する: TREK-1チャネルを媒介する高速経路と,Best1チャネルを媒介する遅い経路で,シナプス機能に異なる影響を及ぼします.
科学分野:
- 神経科学は神経科学である.
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
背景:
- アストロサイトは,グルタミン酸の放出を通してシナプス機能において重要な役割を果たします.
- アストロサイト性グルタミン酸の放出の原因となる正確な分子機構については,議論が続いている.
研究 の 目的:
- アストロサイトから非膀性グルタミン酸の放出に関与する異なる分子経路とチャネルの解明.
- これらの放出メカニズムがニューロンのターゲットに与える影響の違いを理解する.
主な方法:
- Gタンパク質シグナル伝達経路を使用して,チャネル媒介グルタミン酸の放出を調査しました.
- チャンネル局所化を決定するために超構造分析を使用しました.
- ニューロンの受容体におけるグルタミン酸濃度を予測するために,拡散モデリングを使用した.
主要な成果:
- 運動的に異なる2つの非状グルタミン酸放出モードを特定しました.
- 急速モードでは,G(αi) アクティベーション,G(βγ) ディソシエーション,およびTREK-1チャネル開通が含まれています.
- スローモードはCa2+) に依存し,Gαq) の活性化とBest1のチャネル開通を伴う.
- TREK-1はアストロサイトのプロセスに局所化し,Best1はシナプスの近くで見つかる.
- ニューロンのmGluRおよびNMDA受容体に影響を与える異なるグルタミン酸濃度の予測.
結論:
- アストロサイトは,グルタミン酸の放出のために2つの別々のチャネル媒介メカニズムを使用します.
- TREK-1とBest1チャネルは,アストロサイト性グルタミン酸シグナル伝達のための明確な経路を提供します.
- これらの経路は,特定のニューロンの受容体をターゲットにすることで,シナプス機能を差異的に調節します.
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