リボソームRNAの種別転写を制御する分子機構
S P Bell1, C S Pikaard, R H Reeder
1Howard Hughes Medical Institute, Department of Biochemistry, University of California, Berkeley 94720.
Cell
|November 3, 1989
まとめ
種特有の転写因子 hUBF と xUBF は,類似のDNAを結合しますが,互いを置換することはありません. SL1との明確なタンパク質相互作用が,種特有のプロモーター活性化を決定する.
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
- バイオケミストリー バイオケミストリー
背景:
- リボソームRNA (rRNA) の転写は細胞成長に不可欠であり,RNAポリメラーゼI (Pol I) によって調節されます.
- rRNA遺伝子転写におけるプロモーター認識は,種特異性を表し,これはよく理解されていない現象である.
- 人間のUBF (hUBF) やXenopus UBF (xUBF) のような転写因子は,Pol I転写の重要な調節因子である.
研究 の 目的:
- rRNA転写における種別プロモーター認識の分子基盤を調査する.
- 種特異性がDNA結合またはタンパク質-タンパク質相互作用によって媒介されているかどうかを判断する.
主な方法:
- 人間のUBF (hUBF) とクセノプスのUBF (xUBF) の分離と特徴付け.
- 浄化された因子とプロモーターDNAを使用して再構成された転写アッセイ.
- 生物化学的方法を使用して,UBF因子とSL1 (種特有のPol I活性化剤) の複合形成の分析.
主要な成果:
- hUBFとxUBFは,rRNA遺伝子プロモーター内の同じDNA配列要素に結合する.
- hUBFとxUBFは,再構成された転写システムでは機能的に互換性がない.
- hUBFとxUBFは,プロモーターの起源の種に関係なく,ヒトSL1と異なる複合体を形成します.
結論:
- rRNA遺伝子転写における種特異性は,UBF因子によるDNA配列認識によってのみ決定されるものではありません.
- UBFとSL1の間の特定のタンパク質-タンパク質相互作用は,種特有のプロモーター選択性の重要な決定因子である.
- これは,種特有の遺伝子発現の調節における転写因子複合体の形成の重要性を強調しています.
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