核の毛穴はセルロースで膨張し,収縮する

Christian E Zimmerli^1,2,3, Matteo Allegretti^1,3, Vasileios Rantos^4,5

¹Structural and Computational Biology Unit, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany.

Science (New York, N.Y.)

|November 11, 2021

まとめ

核孔複合体 (NPC) は動的にサイズを変更します. 成長する細胞では,NPCは膨張しますが,ストレス下では収縮し,核膜の緊張とNPCの形状の間の関係を明らかにします.

科学分野:

細胞生物学
構造生物学
バイオ物理学

背景:

核孔複合体 (NPC) は,真核細胞における核細胞質輸送に不可欠である.
NPCは ~30の核ポリンから円筒状の構造を形成し,核と細胞質の間の分子輸送を調節する.
NPCのダイナミックな性質と形状の変化は完全に理解されていません.

研究の目的:

生体細胞におけるNPCの大規模な形状の変化を調査する.
NPCのサイズ変化を制御する分子機構と生理学的条件を解明する.
核膜の緊張とNPC構造の間のリンクを確立する.

主な方法:

NPCを現場で視覚化するために,冷凍電子トモグラフィーを用いた.
NPCの構成を再構築するために統合的構造モデリングが使用されました.
指数関数的な成長,エネルギー枯渇,オスモティックストレスのような細胞条件が適用されました.

主要な成果:

NPCは指数関数的に成長する細胞で膨張した形状を示した.
NPCは細胞のエネルギー枯渇と高圧的オスモティック・ストレスの条件下で逆転的に収縮する.
これらの発見は,NPCの形状が細胞の生理状態に敏感であることを示唆しています.

結論:

この研究は,NPCの直径が静的ではなく,細胞状態によって変化することを明らかにしています.
核包膜の緊張がNPCの形状に影響するモデルが提案されています.
これは,核細胞プラズマ輸送のダイナミックな調節に関する新しい洞察を提供します.

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