テロメアヘテロクロマチンから転写抑制剤SIR3の拡散
A Hecht1, S Strahl-Bolsinger, M Grunstein
1Department of Biological Chemistry, UCLA School of Medicine and Molecular Biology Institute, Los Angeles, California 90095, USA.
Nature
|September 5, 1996
まとめ
SIR3は酵母ヘテロクロマチンの重要な構造成分であり,他のタンパク質やヒストンと大きな複合体を形成します. このタンパク質はテロメアから広がり,隣接する遺伝子を抑制し,静止されたクロマチンの構造を確立します.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- イースト生物学 イースト生物学
背景:
- サッカロマイセス・セレヴィシアのテロメアとHMロシは,転写抑制とヘテロクロマチン構造を示しています.
- トランス作用因子RAP1,SIR3およびSIR4は,テロメアおよびHM静音化に不可欠です.
- これらの要因によるヒストン依存抑制の正確なメカニズムは不明である.
研究 の 目的:
- ヘテロクロマチン構造の確立と維持におけるSIR3の役割を明らかにする.
- SIR3の他の静音化因子およびヒストンとの相互作用を調査する.
- 酵母染色体内のSIR3のインビヴォの局所化と拡散を決定する.
主な方法:
- コイムノプレシピテーションは,タンパク質複合体を特定するための測定法です.
- ヒストンアミノ端末とのインビトロ相互作用研究.
- in vivoの局所化を評価するためのクロマチンのクロスリンク実験.
- 静音化を評価するための遺伝子発現分析.
主要な成果:
- SIR3は,SIR4,RAP1,ヒストンと大きなクロマチン関連タンパク質複合体を形成する.
- SIR3はヒストンH3およびH4アミノ端末と相互作用する.
- SIR3は,HMRa,HMLalpha,およびテロメアにインビボ局所化されています.
- SIR3の過剰発現により,隣接する染色体に広がります.
結論:
- SIR3は酵母ヘテロクロマチンの構造成分です.
- SIR3は,染色体に沿って拡散することによってヒストン依存遺伝子抑制を媒介する.
- 大きなタンパク質複合体の形成は,ヘテロクロマチンの確立と維持に不可欠です.
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