BUD2は,Bud1/Rsr1のGTPアゼ活性化タンパク質をコードし,酵母における適切な芽部部位選択のために必要である
H O Park1, J Chant, I Herskowitz
1Department of Biochemistry & Biophysics, University of California, San Francisco 94143-0448.
Nature
|September 16, 1993
まとめ
Bud2タンパク質は,酵母芽生えにおけるBud1タンパク質のGTPase活性化タンパク質 (GAP) として作用する. この発見は,Saccharomyces cerevisiaeの芽部部選択を制御する分子メカニズムを明らかにしています.
科学分野:
- 細胞生物学 細胞生物学
- 分子遺伝学 分子遺伝学
- イースト遺伝学 イースト遺伝学
背景:
- 芽生え酵母Saccharomyces cerevisiaeは,軸性または双極性芽部部部位選択を示しています.
- 芽部部位の選択は,細胞の極性および細胞骨格の組織にとって極めて重要です.
- BUD1/RSR1,BUD2,BUD3,BUD4,BUD5を含む5つの遺伝子が,芽部部選択を制御しています.
研究 の 目的:
- ブッドサイト選択の文脈でBud2タンパク質の機能を調査する.
- Bud1タンパク質との関係でBud2タンパク質の生化学的活性を決定する.
主な方法:
- 精製されたBud2タンパク質を用いた生化学分析.
- イースト変異体の芽生えパターンの分析 (染色体欠損と過剰表現).
主要な成果:
- Bud2タンパク質は,Bud1タンパク質のGTPase活性化タンパク質 (GAP) として機能します.
- 浄化されたBud2タンパク質は,Bud1タンパク質によってGTPの水解を刺激する.
- BUD2の削除または過剰発現は,酵母細胞におけるブドサイトのランダムな選択につながります.
結論:
- Bud2pは,Rasの同類であるBud1pのGTPase活性化タンパク質 (GAP) として作用する.
- この相互作用は,Saccharomyces cerevisiaeの適切な芽部選出に不可欠である.
- BUD2遺伝子は,芽生え中の細胞の極性調節に重要な役割を果たしています.
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