酵母におけるヒストンH2BのRad6依存型ユビキチン化

K Robzyk¹, J Recht, M A Osley

¹Program in Molecular Biology, Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.

Science (New York, N.Y.)

|January 22, 2000

まとめ

ヒストンの改変であるウビキチン化H2B (uH2B) は,細胞の成長と微分化に不可欠です. この研究では,酵母におけるH2Bのユビキチン化に責任を持つ主要な酵素としてRad6を特定しています.

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
バイオケミストリーバイオケミストリー

背景:

ウビキチン化ヒストンは脊椎動物の細胞に豊富に存在するが,その機能と調節因子は不明である.
ヒストンの改変は,遺伝子発現と細胞プロセスを調節する上で重要な役割を果たします.

研究の目的:

酵母におけるユビキチン化ヒストンの生物学的な役割,特にユビキチン化H2B (uH2B) の研究.
H2Bのユビキチネーションに起因する細胞因子を特定する.

主な方法:

イースト変異体の遺伝子分析.
ユビキチン化H2B.を検出するための生化学分析.
ユビキチン結合酵素 Ubc2 の特徴と,H2B ユビキチン化におけるその役割.

主要な成果:

ユビキチン化H2B (uH2B) は,Saccharomyces cerevisiae.で特定されました.
H2Bのユビキチネーション部位の変異は,ミト細胞の成長と微分化の欠陥をもたらした.
UH2Bは,ウビキチン結合酵素Ubc2.2が欠乏しているrad6変異体には存在しなかった.

結論:

Rad6は酵母におけるH2Bのユビキチン化に起因する主要な酵素である.
H2Bのユビキチネーションは,ミトーシス細胞の適切な成長と酵母における微分化に不可欠である.

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