閉じ込められた相分離ポリマーの微小環境における不均質な拡散を検知する

Marjan Shayegan¹, Radin Tahvildari¹, Kimberly Metera¹

¹Department of Physics , McGill University , Montreal , Quebec H3A 2T8 , Canada.

Journal of the American Chemical Society

|April 25, 2019

まとめ

細胞機能に不可欠な生物分子凝縮物は,閉じ込め顕微鏡を用いて in vivo サイズで研究されました. 研究者は異常な拡散を観察し動的な細胞構造の中で跳ね返るメカニズムを示唆しました

科学分野:

細胞生物学
バイオ物理学
生物化学

背景:

液体-液体相分離によって形成される生物分子凝縮物は,日益重要な細胞成分として認識されています.
機能に不可欠な構造的組織と生体物理的性質は,特に体内スケールでは十分に理解されていません.
既存の in vitro 試験では,細胞内に存在する濃縮物よりはるかに大きな濃縮物を使用することが多い.

研究の目的:

生物分子凝縮物の構造的組織と生物物理的性質を,生理学的に関連する,in vivoのようなサイズで調査する.
閉じ込められたコンデンサート内の探査粒子のダイナミクスを探求し,コンデンサートのサイズと組成と関連付けます.

主な方法:

生物分子凝縮物の大きさを視覚化して制御するために閉じ込め顕微鏡を用いた.
細胞環境を模倣した特定の閉じ込めの長さスケールを作成しました
内部ダイナミクスを分析するために探査粒子の拡散測定を用いた.

主要な成果:

閉じ込められた凝縮物の中で探査粒子の異常な拡散を観察した.
PEG/デクストランとリボヌクレオプロテイン (RNP) コンデンサットの両方で異質なダイナミクスが検出されました.
非ガウスの動態を説明するために,ジャンプ拡散メカニズムを提案した.
RNP濃縮物ではなくデクストラン濃縮物での探査粒子の拡散は濃縮物サイズに依存していることが判明した.

結論:

閉じ込め顕微鏡は,生物学的関連スケールでの生物分子の凝縮物の研究を可能にします.
異常な拡散と異質なダイナミクスは,凝縮物内の複雑な内部組織と輸送メカニズムを示唆しています.
コンデンサートの大きさは,特にデクストランが豊富なシステムのような特定の組成において,内部ダイナミクスを影響する.

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