240 kdのマルチサブユニットタンパク質複合体CBF3は,芽生えた酵母センターメアの主要な成分です
1Department of Biological Sciences, University of California, Santa Barbara 93106.
Cell
|February 22, 1991
まとめ
発芽中の酵母セントロメア/キネトコアタンパク質複合体CBF3を精製し,特徴づけました. この鍵となる複合体は,セントロメアDNAに特定の結合のために,リン酸化およびアセンブリ因子を必要とします.
科学分野:
- 分子生物学は分子生物学である.
- 細胞生物学 細胞生物学
- 遺伝学 遺伝学とは
背景:
- セントロメアとキネトコアは,細胞分裂中の染色体分離に不可欠です.
- 芽生えた酵母 (Saccharomyces cerevisiae) は,これらの複雑な構造を研究するためのモデルシステムを提供しています.
- CBF3は,酵母センターメアの機能に関与する既知のタンパク質複合体です.
研究 の 目的:
- S. cerevisiae.からCBF3タンパク質複合体を浄化し特徴づけること.
- CBF3.3のDNA結合特性と要件を調査する.
- CBF3複合体のサブユニットとその役割を特定する.
主な方法:
- アフィニティクロマトグラフィーは,タンパク質の浄化に使用されました.
- DNA結合アッセイは,ワイルドタイプと突然変異のセントロメアDNAを用いて行われました.
- DNase Iの足跡は,DNA結合部位を決定するために使用されました.
- リン酸化の役割を評価するために,フォスファターゼ治療が使用されました.
主要な成果:
- CBF3はCBF3A (110kd),CBF3B (64kd),CBF3C (58kd) を含む240kdのマルチサブユニット複合体として精製されました.
- CBF3は,野生型酵母セントロメアDNA (CEN) に特異的に結合するが,変異したCDEIII配列を持つ変異CENDNAには結合しない.
- 浄化されたCBF3には,DNA結合のためのアセンブリ因子/チャペロンが必要です.
- リン酸化によるCBF3サブユニットはDNA結合に必要であり,リン酸化酵素処理は複合体を無効化する.
- 26bpのCDEIIIコンセンサスを含む56bpの領域は,CBF3結合によって保護されています.
結論:
- CBF3は酵母センターメアの結合に不可欠な多サブユニット複合体です.
- リン酸化と特定のDNA配列 (CDEIII) は,CBF3の機能に不可欠です.
- CBF3サブユニットとアセンブリファクターの詳細な特徴づけは正当化されています.
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