メッセンジャーRNAの輸送とセプチン拡散障壁による酵母におけるプラズマ膜の区切り
P A Takizawa1, J L DeRisi, J E Wilhelm
1Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, CA 94143, USA.
Science (New York, N.Y.)
|October 13, 2000
まとめ
酵母細胞は,プラズマ膜の異なるコンパートメントを作り出します. これは,特定のmRNAを芽の先まで輸送し,頸部で拡散障壁を形成し,タンパク質の非対称性を確保することによって達成されます.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- 非対称なタンパク質の局所化は,極性や運命決定などの細胞機能にとって極めて重要です.
- mRNAとタンパク質輸送のメカニズムを理解することは,細胞の組織を解読する鍵です.
研究 の 目的:
- 酵母における非対称なタンパク質の局所化に関与するmRNAを特定し,特徴づけること.
- マザー・ブッド・ネックにおけるmRNA輸送とタンパク質の非対称性の基礎となるメカニズムを解明する.
主な方法:
- 候補mRNAを特定するためのDNAマイクロアレイ分析.
- mRNAとタンパク質の局所化を視覚化するための顕微鏡技術.
- アクトミオシンとセプチンの役割を研究するための遺伝子操作.
主要な成果:
- プラズマ膜タンパク質をコードする識別されたIST2mRNAは,アクトミオシンベースのメカニズムを通じて芽の先端に局所されています.
- マザー細胞と比較して芽のIST2タンパク質濃度が高いことが観察されました.
- マザー・ブッド・ネックにあるセプチン媒介の拡散障壁が,このタンパク質の非対称性を維持することを実証した.
結論:
- 酵母細胞は,神経細胞や上皮細胞に見られるような,プラズマ膜の異なる区画を確立します.
- mRNAの局所化および拡散バリアは,細胞の非対称性を生み出すための重要なメカニズムです.
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