脂質過酸化は液体-液体相分離を駆動し,生物膜におけるラフトタンパク質分割を妨げます

Muthuraj Balakrishnan^1,2, Anne K Kenworthy^1,2

¹Center for Membrane and Cell Physiology, University of Virginia, Charlottesville, Virginia 22903, United States.

Journal of the American Chemical Society

|January 3, 2024

まとめ

脂質過酸化は細胞膜のフラフトを破壊し,その安定性とタンパク質の組成を変化させます. これらの変化は老化,病気,フェロプトーシスと関連しており,潜在的な治療目標を提供します.

科学分野:

生物化学
細胞生物学
膜生物物理学

背景:

脂質過酸化は,フリーラジカルによって引き起こされ,老化,病気,フェロプトーシスに関連しています.
流動性や浸透性といった膜の特性を変化させます
脂質過酸化が生物膜内側組織に与える影響は不明である.

研究の目的:

脂質過酸化がオーダーされた膜領域 (膜ラフト) にどのように影響するかを調査する.
モデルシステムとして,細胞由来の巨大プラズマ膜膀 (GPMVs) を使用する.

主な方法:

GPMVにおけるフェントン反応による脂質過酸化誘導.
液体有序 (Lo) と液体無秩序 (Ld) ドメインの相分離分析
過酸化した脂質,4-ヒドロキシノネナル (4-HNE) アドクトの定量化,およびタンパク質の局所化.

主要な成果:

脂質過酸化は,GPMV相分離をLoとLdドメインに有意に増加させ,Ld相を好む.
過酸化した脂質と4-HNE添加物は,好ましく Ld 段階に蓄積される.
脂質の詰め込みとラフトタンパク質の順序から不順序の領域への転移が観察されました.

結論:

プラズマ膜脂質過酸化は,膜の構造,安定性,および組成を深刻に破壊する.
これらの障害は老化と病気の病理に寄与します
これらの脂質過酸化誘発の膜変化をターゲットにすることで,治療の機会が与えられます.

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