Cdc53は,ユビキチンタンパク質分解経路による分解のために,酸化されたG1サイクリンを標的とする

A R Willems¹, S Lanker, E E Patton

¹Programme in Molecular Biology and Cancer Samuel Lunenfeld Research Institute Mount Sinai Hospital, Toronto, Canada.

Cell

|August 9, 1996

まとめ

芽生えた酵母菌の細胞分裂は,G1サイクリンに依存しています. 研究者らは,Cdc53タンパク質がこれらのサイクリンを分解し,細胞サイクル進行を制御することを発見しました.

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:

芽生えた酵母における細胞分裂は,G1サイクリン (Cln1,Cln2,Cln3) によって活性化されるCdc28サイクリン依存キナーゼによって調節される.
G1サイクリンの急速な分解は,環境信号と細胞分裂のタイミングを結びつける上で極めて重要です.

研究の目的:

Cln2 と関連したタンパク質を特定するために,G1 サイクリン.
Cln2の不安定性および至るところに存在する状態を調節するメカニズムを解明する.

主な方法:

発芽酵母モデルを用いたCln2関連タンパク質の分離.
タンパク質の相互作用,ユビキチン化,およびタンパク質の安定性のインビボ分析.
これらのプロセスにおけるCln2酸化の役割を調査する.

主要な成果:

Cdc53はCln2結合タンパク質として特定されました.
Cdc53は,Cln2の不安定性と,in vivoのユビキチン化に不可欠である.
Cdc53との相互作用,ユビキチン化,分解にはCln2のリン酸化が必要である.
Cdc53は,E2ユビキチン結合酵素Cdc34.3と相互作用する.

結論:

Cdc53は,ユビキチンリガゼ複合体の構成要素である.
この複合体は,ユビキチン-プロテアゾーム経路経由による分解のために,酸化されたG1サイクリンを標的にします.
このメカニズムは,環境のシグナルの反応として,細胞サイクル進行のための重要な制御ポイントを提供します.

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