ユカリオットカルシウム/陽子交換器の交替アクセスのための構造的基礎
Andrew B Waight1, Bjørn Panyella Pedersen, Avner Schlessinger
1Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158, USA.
Nature
|May 21, 2013
まとめ
研究者らは,カルシウム/陽子 (Ca2+/H+) 交換器Vcx1の結晶構造を決定し,その基板に結合し,シトソール向きの形状を明らかにした. これは,Ca2+:cation (CaCA) 超家族に対する最初の構造的洞察を提供します.
科学分野:
- バイオケミストリー バイオケミストリー
- 構造生物学 構造生物学とは
- 細胞生理学 細胞生理学
背景:
- ユカリオットカルシウム (Ca2+) 調節は,オルガネルの結合と迅速な細胞溶液の放出を含むシグナル伝達経路に不可欠です.
- Na+/Ca2+ (NCX) とCa2+/H+ (CAX) 反ポーターを含むCa2+:cation (CaCA) スーパーファミリーは,Ca2+ ホメオスタシスの回復に不可欠です.
- 哺乳類のNCXタンパク質 (SLC8,SLC24ファミリー) は,筋肉,ニューロン,腎臓におけるCa2+を調節する.
研究 の 目的:
- CaCAスーパーファミリーの未知のサイトゾール向きの形状を解明するために.
- CaCAアンチポーターの投機的な輸送メカニズムを理解するために.
- Saccharomyces cerevisiaeの真空Ca2+/H+交換器 (Vcx1) の高解像度結晶構造を決定する.
主な方法:
- Saccharomyces cerevisiae Vcx1.1.の結晶構造を決定しました.
- 2.3 Åの解像度でX線結晶学を用いた.
- サブストラットに結合した,シトソール向きの形状でVcx1を捕獲した.
主要な成果:
- CaCAスーパーファミリー内のCAXファミリーメンバー (Vcx1) の最初の結晶構造.
- CaCAスーパーファミリーの重要なサイトゾール向きの構造を明らかにします.
- 高通量Ca2+輸送を促進する新しい交替アクセスメカニズムのための構造的基盤を提供します.
結論:
- 決定されたVcx1構造は,CaCAスーパーファミリーのメカニズムに関する重要な洞察を提供します.
- これらのアンチポーターがどのように効率的なCa2+輸送を達成するのかを理解するための構造的基盤を確立します.
- 新しい交替アクセスメカニズムは,高通量Ca2+輸送能力を説明します.
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