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Updated: Jul 18, 2026

16:36
Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
Published on: May 18, 2009
イオノトロピックATP受容体によって定義されるリガンドゲートイオンチャネルの新しい構造モチーフ
A J Brake1, M J Wagenbach, D Julius
1Department of Pharmacology, University of California, San Francisco 94143-0450.
Nature
|October 6, 1994
まとめ
アデノシン三リン酸 (ATP) は細胞外伝達物質として作用し,細胞表面受容体を活性化します. クローンされたP2x受容体は,他のチャネルとの機能的な類似性にもかかわらず,異常なサブユニット構造を明らかにし,収束進化を強調しています.
科学分野:
- 分子生物学は分子生物学である.
- 神経科学は神経科学である.
- 細胞生物学 細胞生物学
背景:
- アデノシントリフォスファート (ATP) は,様々な組織で細胞外伝達物質として機能します.
- ATPは,Gタンパク質結合受容体やリガンドゲートイオンチャネルを含む細胞表面受容体を活性化します.
- P2x受容体として知られるATPゲートチャネルは,滑らかな筋肉細胞やニューロンに存在し,脱極化とカルシウムイオン (Ca2+) の侵入を媒介する.
研究 の 目的:
- クローンされたP2x受容体のサブユニット構造を特徴付ける.
- P2x受容体と他のリガンドゲートチャネル間の機能的類似性の構造的基礎を調査する.
- P2x受容体とアポトーシスに関与する遺伝子の間の進化的関係を調査する.
主な方法:
- P2x受容体の遺伝子クローンと配列分析.
- 推論されたP2x受容体配列と既知のチャネル構造の比較.
- シーケンス類似性分析は,チモサイトアポトーシス中に活性化される遺伝子であるRP-2と似ています.
主要な成果:
- クローンされたP2x受容体の推論された配列は,異常なサブユニット構造を予測します.
- この構造は,電圧無感のカチオンチャネルに似ており,機能的に類似した受容体とは異なる.
- P2x受容体とRP-2遺伝子の間の配列の類似性が見つかりました.
結論:
- P2x受容体は収束進化の例であり,異なる構造的サブユニットから生じる類似の機能を持つ.
- 構造的な差異は,ATPゲートチャネルのユニークな進化の経路を示唆しています.
- RP-2遺伝子は,ATPまたはアポトーシス中に放出された他の代謝産物の受容体をコードする可能性があります.
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