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Updated: Jul 11, 2026

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Assay for Adhesion and Agar Invasion in S. cerevisiae
Published on: November 8, 2006
酵母CDC28-p40タンパク質キナーゼ複合体の二重調節:細胞サイクル,フェロモン,そして栄養素制限効果
Cell
|September 11, 1987
まとめ
細胞サイクル進行は,G1相に特異的なCDC28キナーゼ活性に依存しています. アクティベーションは,S段階または交配に入ると失われ,活性化因子の必要性を示します.
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.
- バイオケミストリー バイオケミストリー
背景:
- CDC28遺伝子産物は,酵母における細胞循環の重要な調節因子である.
- 40 kDaのポリペプチドは,CDC28遺伝子製品と関連することが知られている.
研究 の 目的:
- 細胞サイクル中のCDC28タンパク質キナーゼ活性調節を調査する.
- 40 kDaポリペプチドの特定のリン酸化を制御する要因を特定する.
主な方法:
- 免疫複合体の降水により,CDC28遺伝子産物を隔離する.
- 40 kDaのポリペプチドのリン酸化を測定するためのインビトロキナーゼアッセイ.
- 異なる細胞サイクルフェーズと変異体からの抽出物を用いた補充測定法.
主要な成果:
- p40リン酸化で測定されるCDC28タンパク質キナーゼ活性度は,G1相細胞の分裂においてのみ検出される.
- 細胞がG1から抜け出してS相または前結合状態に入るとき,その活動が失われます.
- 非G1細胞からの抽出物は,交換可能な活性化因子に欠けているが,静止細胞とフェロモン処理細胞は,この因子を含んでいるが,不活性なキナーゼを持っている.
- cAMP欠乏の突然変異体は,静止細胞に似た特徴を示します.
結論:
- CDC28のタンパク質キナーゼの活性度は厳格に調節され,細胞周期のG1段階に限定されています.
- 細胞サイクル進行は,CDC28キナーゼのための交換可能な活性因子の存在と活性によって制御されます.
- このキナーゼの調節は,S相への入り込みや不適切な条件下で交配を防ぐために極めて重要です.
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