陽子は,C. elegansの筋肉収縮の伝達物質として作用する
Asim A Beg1, Glen G Ernstrom, Paola Nix
1Neuroscience Program, University of Utah, Salt Lake City, UT 84112-0840, USA.
Cell
|January 15, 2008
まとめ
陽子は直接腸内細胞に信号を送り,神経を回避して筋肉を収縮させる. この研究は,陽子の放出と受容のメカニズムを特定し,C. elegans.における新しい細胞間通信を明らかにしています.
科学分野:
- 細胞生物学 細胞生物学
- 神経生物学 神経生物学とは
- 生理学 生理学とは
背景:
- 筋肉の収縮は,通常,運動ニューロンの神経伝達物質によって調節されます.
- C. elegansの排泄運動プログラムは,神経の入力から独立して,後部体の筋肉の収縮を伴う.
研究 の 目的:
- ニューロンのシグナル伝達がない場合にC. elegansの排便運動プログラム中の筋肉収縮のメカニズムを調査する.
- この非ニューロンの筋肉活性化に関与するシグナル伝達分子と受容体を特定する.
主な方法:
- 筋肉の収縮を観察するために,C. elegansのモデルを使用しました.
- 腸と筋肉の間の細胞外pHの変化を測定した.
- PBO-4 (Na+/H+イオン交換器) とPBO-5/PBO-6 (プロトンゲートカチオンチャネル) 遺伝子の役割を調査した.
- ヘテロログな発現の測定を行い,受容体の活性化値を決定する.
主要な成果:
- 陽子は,筋肉の収縮を刺激するために,腸細胞からの直接的な伝達物質として作用することを示した.
- 腸と筋肉の間の細胞外空間は,収縮前に酸性化されていることが示された.
- 陽子の放出に不可欠なPBO-4と,筋肉による陽子の受容に不可欠なPBO-5/PBO-6を特定した.
- PBO受容体がpH 6.8.8で活性化することが判明した.
結論:
- プロトンが筋肉の収縮を媒介する異常な細胞間通信機構を確立した.
- 伝統的な神経伝達から独立したシグナル伝達のための新しい経路を強調した.
- プロトンベースの細胞間信号伝達の主要な分子プレーヤーを特定しました.
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