ストレスシグナル伝達におけるミトコンドリア標的配列の直接的な役割

Zixuan Yuan¹, Megan Balzarini¹, Marina Volpe¹

¹Life Sciences Institute, Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada.

Nature

|December 10, 2025

まとめ

ミトコンドリアのストレスはMge1によって感知されストレス反応遺伝子を活性化するために核に移動しますミトコンドリアの健康を示しています

科学分野:

細胞生物学
ミトコンドリア生物学
分子生物学

背景:

ミトコンドリアのタンパク質の輸入は臓器の機能と細胞の健康に不可欠です
タンパク質インポートの欠陥はミトコンドリアのタンパク質インポート反応 (mitoCPR) のようなストレス反応を誘発する.
ミトコンドリアインポートの欠陥の背後にある感知メカニズムは,大部分が特徴づけられていない.

研究の目的:

ミトコンドリアタンパク質の検知メカニズムを特定する
ミトコンドリアのタンパク質輸入反応 (mitoCPR) に関するMge1の役割を明らかにする.
ストレスシグナル伝達におけるミトコンドリアの標的配列の機能を調査する.

主な方法:

芽生えた酵母をモデル生物として利用した.
ミトコンドリアのストレス下でのMge1の局所化と相互作用を調査した.
ミトCPR標的遺伝子の転写活性化を分析した.
ストレス反応におけるMge1ミトコンドリア標的配列の役割を調べた.

主要な成果:

Mge1は芽生えた酵母の中でストレスメッセンジャーとして機能する.
輸入されていないMge1は,ミトコンドリアのストレスで核に転移する.
Mge1は,転写因子 Pdr3と相互作用して,ミトCPR遺伝子転写を誘導する.
Mge1のミトコンドリア標的配列はミトCPR誘導に不可欠で十分である.

結論:

Mge1はミトコンドリアのタンパク質輸入欠陥の核局所感知器として作用する.
ミトコンドリアの標的配列は,ミトコンドリアの健康を示すシグナル分子として機能する.
これらの発見はミトコンドリアのストレスと損傷を感知するための新しいメカニズムを明らかにしています

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