B. subtilisの第1のコンパートメント特異的転写因子であるSigma Fは,抗シグマ因子によって調節され,これはタンパク質キナーゼでもある
K T Min1, C M Hilditch, B Diederich
1Department of Biochemistry, University of Oxford, England.
Cell
|August 27, 1993
まとめ
SpoIIABタンパク質キナーゼは,B. subtilis sporulationの間に転写因子シグマFの活動を調節する. SpoIIABによるSpoIIAAのリン酸化は,プレスポールのシグマF抑制を解放し,特定の遺伝子発現を可能にします.
科学分野:
- 微生物学 微生物学とは
- 分子生物学は分子生物学である.
- バクテリアの遺伝学
背景:
- B. subtilis sporulation.のために,コンパートメント特有の転写は極めて重要です.
- このプロセスの鍵となるのは,転写因子シグマFの活性である.
- SPOIIAAとSPOIIABは,シグマFの活性調節に関与している.
研究 の 目的:
- SpoIIAAとSpoIIABによるシグマF活動の規制メカニズムを調査する.
- スポルレーション中の転写制御におけるSpoIIABの役割を明らかにする.
主な方法:
- 精製されたSpoIIABとシグマFを用いたインビトロ転写アッセイ.
- SpoIIABのタンパク質キナーゼ活性に関する生化学的分析.
- SpoIIAA.AA.のリン酸化部位の特定について
主要な成果:
- 浄化されたSpoIIABは,シグマF誘導転写をin vitroで抑制する.
- SpoIIABは,タンパク質キナーゼとして機能し,セリン残基の SpoIIAA をリン酸化する.
- SpoIIABは,細菌のヒスティジンタンパク質キナーゼと類似性を示しています.
結論:
- SpoIIAAのSpoIIAB媒介のリン酸化は,シグマF阻害を解放する責任を負う.
- このリン酸化は,B. subtilis sporulationにおけるコンパートメント特異の転写を容易にする可能性が高い.
- 潜在的なモデルとしては,SpoIIABとリン酸化SpoIIAA.の複雑な形成が含まれる.
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