酵母菌におけるセルフェイト決定因子をコードするRNAのアクチン依存の局所化
P A Takizawa1, A Sil, J R Swedlow
1Howard Hughes Medical Institute, Department of Cellular and Molecular Pharmacology, University of California, San Francisco 94143-0450, USA.
Nature
|September 4, 1997
まとめ
酵母細胞におけるメッセンジャーRNA (mRNA) の局所化は,細胞運命を決定するための非対称なタンパク質分布を保証する. Ash1 mRNAは,アクチン細胞骨格を通して子芽に輸送され,細胞の発達を調節します.
科学分野:
- 細胞生物学 細胞生物学
- 発達生物学 発達生物学とは
- 分子遺伝学 分子遺伝学
背景:
- 細胞プラズマのmRNAの局所化は,エウカリオットの細胞運命を特定するために重要なタンパク質非対称性を生み出します.
- Ash1タンパク質は,芽生えた酵母における細胞酸塩決定体として作用し,子核に局所化することによって,交配型の切り替えを阻害します.
研究 の 目的:
- 発芽酵母におけるAsh1 mRNAの局所化メカニズムを調査する.
- mRNAの局所化は,Saccharomyces cerevisiaeの細胞運命を決定するのにどのように貢献するのかを理解する.
主な方法:
- Ash1 mRNAのローカライゼーションを視覚化するための3次元画像技術.
- 特定のタンパク質 (ミオシンMyo4,アクチンレギュレータBni1) が欠けている酵母変異体におけるAsh1 mRNAの局所化の分析と,無傷の3'未翻訳領域.
主要な成果:
- Ash1 mRNAは,アナファゼ後の細胞の娘芽の遠端に局所され,細胞皮質に関連した粒子を形成します.
- 適切なAsh1 mRNAのローカライゼーションには,無傷の3'未翻訳領域とアクチン細胞骨格が必要です.
- ミオシン (Myo4) の欠如は局所化を妨害し,Bni1 の欠如は母芽頸部での誤局化につながる.
結論:
- Ash1 mRNA粒子は,アクチン繊維に沿って子芽に輸送され,遠端に固定されます.
- Saccharomyces cerevisiaeはRNAの局所化を利用し,高級エウカリオットに類似して,非対称なタンパク質分布と細胞運命を決定します.
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