ガンマチューブリン (Gamma-tubulin) は,センターソームの高度に保存された成分です
T Stearns1, L Evans, M Kirschner
1Department of Biochemistry and Biophysics, University of California Medical School, San Francisco 94143.
Cell
|May 31, 1991
まとめ
高度保存されたタンパク質であるガンマチューブリンは,細胞分裂と微小管組織に不可欠です. この至るところに存在するタンパク質は,細胞構造に不可欠なセンターソームの重要な構成要素です.
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:
- チューブリンタンパク質は,細胞構造と分裂に不可欠なマイクロチューブルを形成します.
- ガンマチューブリンはチューブリンの別々のサブファミリーですが,その正確な役割と保存は完全に理解されていません.
研究 の 目的:
- 様々な種にわたるガンマチューブリン遺伝子をクローン化し,特徴づけること.
- ガンマチューブリンの保存,機能,および局所化を調査する.
主な方法:
- 様々な生物 (X. laevis,S. pombe,トウモロコシ,藻,酵母) の遺伝子クローンと特徴付け.
- 保存を評価するためのタンパク質配列の比較.
- S. pombe.におけるヌル変異による遺伝子機能の分析.
- 細胞内のタンパク質の局所化を決定するための免疫局所化研究.
主要な成果:
- ガンマチューブリン遺伝子は,真核生物全体で高度に保存されており,重要な保存された機能を示しています.
- Schizosaccharomyces pombe gamma-tubulinのゼロ変異は致命的であり,その本質性を強調しています.
- ガンマチューブリン (Gamma-tubulin) は,センターソームのマイナーなタンパク質成分で,特異的に周周中心の物質に局所されています.
- ガンマチューブリンは,マイクロチューブルのデポリメリゼーション後でさえ,センターソームと関連づけられています.
結論:
- ガンマチューブリン (Gamma-tubulin) は,マイクロチューブルの核形成に不可欠な,至る所に存在し,高度に保存されているタンパク質です.
- セントロソームへの局所化は,マイクロチューブル組織と細胞分裂において重要な役割を果たすことを示唆しています.
- ガンマチューブリン (Gamma-tubulin) は,センターソムのマイクロチューブルの核形成機構の不可欠な構成要素である.
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