終結因子Rhoとその共因子NusaAとNusGは,E. coliの異種DNAを沈黙させます
Christopher J Cardinale1, Robert S Washburn, Vasisht R Tadigotla
1Department of Biochemistry, New York University School of Medicine, New York, NY 10016, USA.
まとめ
バクテリアのRho因子は,遺伝子発現を全体的に調節し,転写終了を制御します. Rhoをビシクロマイシンで阻害すると,Escherichia coliのプロファージのような有毒な外来遺伝子を抑制する上でその重要な役割が明らかになる.
科学分野:
- 微生物学 微生物学とは
- バクテリアの遺伝学
- 分子生物学は分子生物学である.
背景:
- バクテリアの転写には,特定の終止信号が必要です.
- ロファクター (Rho factor) は,トランスクリプション終結のためのエンテロバクテリアの不可欠なタンパク質です.
- ビシクロマイシンは,Rho因子の活性を抑制する抗生物質です.
研究 の 目的:
- エシェリキヤ大腸菌の遺伝子発現におけるRho因子のゲノム全体の役割を調査する.
- 翻訳的ニーズに応じた転写をRho因子がどのように調節するかを理解する.
- バイオクロマイシンに対するバクテリアの耐性に対するRho因子抑制の影響を決定する.
主な方法:
- 抗生物質ビシクロマイシンを使用して,Rho因子を阻害しました.
- Rho因子の調節作用に関する全ゲノム分析を行いました.
- ビサイクロマイシン耐性に対する外来DNA要素の除去の効果を評価した.
主要な成果:
- Rho因子は遺伝子発現のグローバルレギュレータとして作用し,転写と翻訳の要求を調整します.
- プロファージと水平的に獲得されたゲノム領域は,Rho因子によって非常に抑制されます.
- 異種のDNA要素を排除することで,ビサイクロマイシンに対する耐性を高めます.
- 異種DNA要素が欠けている縮小ゲノム細菌は,Rho共因子NusaAとNusGを必要としない.
- ラックプロファージの切除は,ビサイクロミシン耐性を高め,ヌスGの切除を可能にします.
結論:
- NusAとNusGによってサポートされるRho終結は,Escherichia coli.の異種遺伝子の毒性の活動を抑制するために不可欠です.
- Rho-NusA-NusGの転写終結システムは,水平的に取得された要素を制御することによって,ゲノムの安定性を維持する上で重要な役割を果たします.
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