ステロールに富んだ膜領域は,分裂酵母細胞の極性性を定義する

Tatyana Makushok¹, Paulo Alves², Stephen Michiel Huisman³

¹University of California, San Francisco, 600 16(th) Street, San Francisco, CA 94143, USA.

Cell

|May 17, 2016

まとめ

ステロールに富んだ膜ドメインは酵母細胞の表面に形成され,極に移動することで細胞の極化を促進する. このプロセスは細胞機能に不可欠であり,cdc42pの極性因子とは無関係に発生する.

科学分野:

細胞生物学
生物化学
微生物学

背景:

細胞の偏化は生物の機能に不可欠であり,細胞骨格は対称性を破る上で重要な役割を果たします.
極性生成の正確なメカニズムは,特に飢餓終了時に,まだ完全に理解されていません.

研究の目的:

飢餓脱出時に分裂酵母細胞の分極化の分子基礎を調査する.
細胞の極性の開始と維持におけるステロールと膜ドメインの役割を解明する.

主な方法:

ステロール豊富な膜 (SRM) ドメインの形成と分裂酵母の動態の観察.
細胞骨格要素 (マイクロチューブル,F-アクチン) と極性因子 (cdc42p,tea1p,for3p,bud6p) の関与の分析

主要な成果:

細胞の偏化は,デノボ・ステロール生物合成と細胞表面への配送によって開始され,ランダムに分布したSRMドメインを形成する.
これらのSRMドメインは,その後,microtubule依存因子 tea1pによって分極され,cdc42pとは独立しています.
F-アクチンはSRMの分極化に必要ですが,F-アクチンの組織因子for3pとbud6pは不要です.

結論:

ステロールに富んだ膜ドメインは細胞の二極化に不可欠です.
SRMは,成長と極性機械の組み立てのためのプラットフォームとして機能します.
この研究は,ステロールダイナミクスを含む細胞の極化のための新しい,cdc42p独立の経路を明らかにした.

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