ミトコンドリアタンパク質の輸入の規制は,シトソリックキナーゼによって行われる
Oliver Schmidt1, Angelika B Harbauer, Sanjana Rao
1Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, Freiburg, Germany.
Cell
|January 11, 2011
まとめ
CK2やPKAのようなサイトゾリックキナーゼは,ミトコンドリアタンパク質の輸入を調節する. CK2はTOM複合体の組み立てを促進し,PKAは特定の条件下でそれを阻害し,ミトコンドリアへのタンパク質の侵入を制御します.
科学分野:
- 細胞生物学 細胞生物学
- ミトコンドリア生物学
- 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,膜に結合したトランスロカセスを通して核にコードされたタンパク質を輸入する.
- これらのタンパク質輸入機構の規制,特に外膜のトランスロカゼ (TOM複合体) はよく理解されていません.
研究 の 目的:
- 外膜のトランスロカゼ (TOM複合体) とミトコンドリアタンパク質のインポートを調節するシトソリックキナーズの役割を調査する.
主な方法:
- TOMの複合成分のリン酸化分析. トムの複合成分のリン酸化分析.
- カゼインキナーゼ2 (CK2) とタンパク質キナーゼA (PKA) がTOM複合体の生体生成と機能に及ぼす影響を調査する.
- キナーゼ不活性化時にミトコンドリアタンパク質の輸入レベルを評価する.
主要な成果:
- TOM複合体は,細胞塩基キナーゼCK2およびPKAによってリン酸化される.
- CK2は,Tom22とMim1のリン酸化を通じたTOM複合生物生成を促進し,他のTomタンパク質の輸入に不可欠である.
- PKAは,呼吸器以外の条件下でTom70をリン酸化し,その受容体活性と代謝産物媒体の輸入を阻害する.
結論:
- 細胞塩基キナーゼCK2とPKAは,ミトコンドリアのタンパク質輸入を調節する上で二重の役割を果たします.
- CK2はTOM複合体の生体生成とミトコンドリア全体のタンパク質インポートを刺激する.
- PKAは特定の輸入経路を阻害し,ミトコンドリア機能の微分キナーゼ媒介調節を示しています.
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