ミトコンドリアカルシウムユニポーターの進化的多様性
Alexander G Bick1, Sarah E Calvo, Vamsi K Mootha
1Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.
Science (New York, N.Y.)
|May 19, 2012
まとめ
ミトコンドリアカルシウムユニポーター (Mitochondrial calcium uniporter, MCU) とそのパートナーであるMICU1は,真核生物全体で見られ,古代の起源を示唆しています. 一部のバクテリアは,関連するカルシウムチャネルをもっている可能性があります.
科学分野:
- ミトコンドリア生物学 ミトコンドリア生物学
- 分子進化は分子進化である.
- イオンチャネル機能のイオンチャネル機能
背景:
- ミトコンドリアは細胞カルシウムを調節する.
- ミトコンドリアカルシウムユニポーター (MCU) は,カルシウム吸収を促進します.
- MCUコンプレックスには,毛孔サブユニットMCUと規制サブユニットMICU1.1が含まれています.
研究 の 目的:
- MCUとMICU1.1の進化分布を調査する.
- ミトコンドリアのカルシウムユニポーターの系統遺伝的起源を決定する.
- MCUの潜在的プロカリオット同類体を探求する.
主な方法:
- MCUとMICU1のホモログの遺伝子解析.
- ユーカリオットとバクテリアの領域における比較ゲノミクス.
主要な成果:
- MCUとMICU1のホモロゴスは,真核生物で広く存在し,ほとんどの系統で同時に発生します.
- 特定の原生類および真菌群で観察されたMCUおよびMICU1の損失.
- いくつかのバクテリアのゲノムで特定された推定的なMCUホモログ.
結論:
- ミトコンドリアのカルシウムユニポーターは,おそらく真核生物の進化の初期に発生した.
- バクテリアのMCUホモログの存在は,古代のプロカリオットカルシウムチャネルを示唆しています.
- 進化的分析は,ミトコンドリアの機能についての洞察を提供します.
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