デウビキチン化酵素がSIR4と相互作用し,S. cerevisiaeの静音化を調節する
1Department of Microbiology, University of California, San Francisco 94143, USA.
Cell
|August 23, 1996
まとめ
酵母静止タンパク質SIR2,SIR3,SIR4は,デウビキチン化酵素UBP3.3と相互作用する. UBP3を削除すると,テロメアと交配型ロキュの近くの遺伝子サイレンシングが強化され,UBP3がサイレンシング阻害剤であることを明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- イースト遺伝学 イースト遺伝学
- エピジェネティクス エピジェネティクス
背景:
- SIR2,SIR3,SIR4タンパク質を含むサイレント・インフォメーション・レギュレータ (SIR) 複合体は,酵母における転写サイレンシングに極めて重要です.
- この静音化は,静音交配型ロシやテロメアを含む特定のゲノム領域で起こります.
研究 の 目的:
- SIR4.4と結合するタンパク質を特定する.
- 転写サイレンシングにおけるSIR4結合タンパク質の役割を調査する.
主な方法:
- タンパク質親近性染色体は,SIR4.4と相互作用するタンパク質を分離するために使用されました.
- UBP3の静音化への影響を評価するために,遺伝子消去分析が行われました.
主要な成果:
- SIR2,SIR3,および2つの新しいタンパク質 (69kDaと110kDa) が,SIR4と密接に関連していることが判明しました.
- 110 kDaのタンパク質は,酵母によるデウビキチン化酵素であるUBP3として特定されました.
- UBP3遺伝子の削除により,テロメアとサイレントペアタイプロシオのサイレンシングが著しく改善されました.
結論:
- UBP3は,酵母における転写サイレンシングの阻害剤として作用する.
- UBP3は,SIRタンパク質複合体の活性または構成を調節する可能性があります.
- これらの発見は,遺伝子サイレンシングを制御する新しい規制メカニズムに光を当てています.
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