湿潤は,相分離区間と細胞溶液の自を調節する

Jaime Agudo-Canalejo^1,2,3, Sebastian W Schultz^4,5, Haruka Chino⁶

¹Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, UK.

Nature

|January 21, 2021

まとめ

細胞滴はオートファギーで除去され,その過程で二重膜の膀が形成されます. この研究では滴の性質と膜の折り合いがこの"流体消化"メカニズムを駆動する仕組みを明らかにしています

科学分野:

細胞生物学
バイオ物理学

背景:

液体-液体相分離は細胞滴を生成しますが,その除去メカニズムは不明です.
細胞分解プロセスであるオートファギーは,二重膜のオートファゴソームを含むドロップレット除去に関与しています.

研究の目的:

細胞内で自己ファゴソームがタンパク質を含むドロップレット (p62/SQSTM1) を封じ込めることを研究する.
液体オートファギーを駆動する物理的メカニズムを明らかにする.

主な方法:

部分的に濡らすことによるタンパク質フリー滴の水泡形成を示すインビトロ実験.
ドロップレット表面張力と膜の曲線に基づく最小物理モデルの開発.
生体細胞における自己ファゴソーム連鎖の観察

主要な成果:

表面張力による部分浸潤により,オートファゴソームのような二重膜の膀が形成されます.
膜の屈曲は,断片的または完全なドロップレットの収縮につながる可能性があります.
オートファゴソーム連鎖は粘着の変動に強固であるが,濡れることは膜の曲げる方向に影響する.

結論:

ドロップレットオートファギーは,エラストキャピラリティと湿潤現象によって引き起こされます.
ドロップルは,オートファゴソームの組み立てプラットフォームとして機能し,オートファギー基板として機能する間で切り替えることができます.
湿潤は細胞組織とドロップレットの除去に重要な役割を果たします.

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