統合的ゲノミクスは,ミトコンドリアのカルシウムユニポーターの不可欠な構成要素としてMCUを識別します
Joshua M Baughman1, Fabiana Perocchi, Hany S Girgis
1Department of Systems Biology, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Nature
|June 21, 2011
まとめ
研究者らは,ミトコンドリアカルシウムユニポーター (MCU) を,ミトコンドリアカルシウム吸収を調節する重要なタンパク質として特定しました. この発見は,細胞機能に不可欠なミトコンドリアへのカルシウム輸送の分子基礎を明らかにしています.
科学分野:
- ミトコンドリア生物学 ミトコンドリア生物学
- 分子細胞生物学 分子細胞生物学
- バイオケミストリー バイオケミストリー
背景:
- ミトコンドリアは,ルテニウム赤に敏感なユニポーターを通して,細胞のカルシウム (Ca2+) レベルを調節する.
- この重要なCa2+ユニポーターの分子アイデンティティは,広範な生体物理学的研究にもかかわらず,難解であるままです.
研究 の 目的:
- ミトコンドリアカルシウムユニポーターの分子成分を特定するために.
- ミトコンドリアのCa2+輸送に関与する,新たに特定されたタンパク質の機能と相互作用を特徴づける.
主な方法:
- 比較プロテオミクスは,MICU1を推定レギュレータとして識別する.
- 系統遺伝的プロファイリング,RNA共表現,およびタンパク質共表現分析により,MCUを予測する.
- 遺伝子サイレンシング,生化学分析,およびMCU機能の検証のための薬理学的抑制.
主要な成果:
- 収束生物情報分析により,CCDC109A (MCUと呼ばれる) がMICU1.1と相互作用する新型トランスメブランタンパク質として特定されました.
- MCUはミトコンドリア内膜でオリゴーマーを形成し,ミトコンドリアのCa2+吸収に不可欠です.
- MCUは,ミトコンドリアの呼吸や膜ポテンシャルに影響を与えることなく,廃止されたCa2+吸収を静止します.
結論:
- ミトコンドリアカルシウムユニポーター (MCU) は,ミトコンドリアCa2+吸収機構の重要な構成要素です.
- 超膜ヘリクと酸性残留を含むMCUの構造は,その機能にとって非常に重要です.
- この研究は,ミトコンドリアカルシウム輸送の分子基礎を明らかにしています.
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