マイクロチューブル切断タンパク質であるカタニンは,WD40を含むサブユニットを使用してセンターソームを標的とする新しいAAA ATPaseです
J J Hartman1, J Mahr, K McNally
1Department of Cellular and Molecular Pharmacology, University of California, San Francisco 94143, USA.
Cell
|May 6, 1998
まとめ
細胞分裂に不可欠なタンパク質であるカタニンは,2つのサブユニットを持っています. p60サブユニットは微小管の切断を行うが,p80サブユニットは細胞へのカタニンを標的とする.
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.
- バイオケミストリー バイオケミストリー
背景:
- 微小管のダイナミクスは,ミトーシス・スパインドルの機能にとって極めて重要です.
- カタニンは,セントロソームに局限した微小管切断タンパク質複合体です.
- カタニンは,60 kDa (p60) と80 kDa (p80) のサブユニットで構成されるヘテロダイマーです.
研究 の 目的:
- カタニンサブユニットの配列と特定の活動を決定する.
- マイクロチューブルの分解におけるp60およびp80サブユニットの機能的な役割を解明する.
- センターソームへのカタニンの局所化のメカニズムを理解する.
主な方法:
- カタニンのサブユニットのタンパク質発現と浄化.
- ATPaseと微小管切断活動を測定するインビトロアッセイ.
- サブユニット局所化を研究するために哺乳類の細胞を感染させる.
主要な成果:
- p60サブユニットは,新しいAAAファミリーATPaseとして特定されています.
- 発現したp60は,p80とは独立して,微小管で刺激されたATPアゼと微小管切断活動を表している.
- p80サブユニットは,p60二分化とは無関係に,WD40の繰り返しを含み,センターソームに局所する.
- p80のWD40ドメインはp60の二分化には関与していない.
結論:
- カタニンの酵素活性はp60サブユニットにあります.
- p80サブユニットは,カタニンをセンターソームに標的にする機能を持っています.
- このサブユニット分離により,カタニン複合体内の異なる機能的役割が認められる.
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