異なる分裂シグネチャーはミトコンドリアの分解または生体生成を予測する
Tatjana Kleele1, Timo Rey2, Julius Winter2
1Institute of Physics, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland. tatjana.kleele@epfl.ch.
Nature
|May 6, 2021
まとめ
ミトコンドリア分裂には2つの異なるタイプがあります:損傷した部分を除去するための周辺分裂と,新しいミトコンドリアを作成するためのミッドゾーン分裂です. これらのプロセスは異なる分子メカニズムによって制御され,細胞がミトコンドリアの運命をどのように制御するかを説明します.
科学分野:
- 細胞生物学
- ミトコンドリア動力学
- 分子機構
背景:
- ミトコンドリア分裂は細胞の健康に不可欠であり,代謝,増殖,アポトーシスを調節する.
- 機能不全のミトコンドリア分裂は 神経変性,心血管疾患,癌と関連しています
- 既存のモデルは,ミトコンドリアがクリアされるか増殖するかを,分裂がどのように決定するかを説明できない.
研究 の 目的:
- ミトコンドリア分裂の仕組みを調査する
- 異なる分裂イベントが異なるミトコンドリアの運命 (ミトファジー対増殖) をどのように導いているかを明らかにする.
- 周縁と中部の分裂に関与する分子プレーヤーを区別する.
主な方法:
- 活細胞構造化照明顕微鏡を用いて高解像度のミトコンドリア動態を記録した.
- アフリカの緑猿のCos-7細胞とマウスの心筋細胞における何百もの分裂現象の分析
- 各種の分裂に特異的な分子調節体の識別と特徴付け
主要な成果:
- ミトコンドリア分裂の2つの異なるタイプが発見されました: 周辺部と中部部です.
- リゾソームとの接触による周辺分裂は,損傷したミトコンドリアの除去を容易にする.
- エンドプラズマ網,アクチン,MFFによって調節されるミトコンドリアの分裂は,ミトコンドリアの増殖を促進する.
- 両方の分裂タイプは,ダイナミン関連タンパク質1 (DRP1) に依存しているが,周辺分裂はさらにFIS1によって制御される.
結論:
- 異なる分子メカニズムは 周辺と中帯のミトコンドリア分裂を制御する.
- 周辺分裂はミトファギーを介して損傷したミトコンドリア物質の選択的除去を可能にします.
- ミトコンドリアの生殖と増殖を促します
- これらの発見は,細胞がミトコンドリアの質と量を制御するために独立して分裂を制御する方法を理解するための枠組みを提供します.
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