ストカスティックな単分子イベントは,細菌細胞のフェノタイプスイッチングを誘発する
Paul J Choi1, Long Cai, Kirsten Frieda
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Science (New York, N.Y.)
|October 18, 2008
まとめ
単一分子のモニタリングは,Escherichia coli細胞が現象型を切り替える方法を明らかにします. DNAからの乳糖抑制剤解離のストキャスティックイベントは,細胞の行動を決定する,浸透性の発現を誘発します.
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
- バイオフィジックス 生物物理学
背景:
- エシェリキア・コライのラック・オペロンは,乳糖代謝を調節する.
- 遺伝子発現は,遺伝的に同一の細胞でも,フェノタイプのスイッチングを示すことができます.
- このスイッチングの分子基盤を理解することは,細胞生物学にとって極めて重要です.
研究 の 目的:
- エシェリキア大腸菌におけるフェノタイプスイッチングの背後にある分子メカニズムを調査する.
- 誘導状態と非誘導状態の間のラックオペロンの移行方法を解明する.
- 細胞現象型の決定における単一分子イベントの役割を特定する.
主な方法:
- 単分子光顕微鏡を用いて,乳糖浸透をモニタリングした.
- 個々の細胞内の光で標識されたタンパク質のリアルタイム観察.
- 単一分子レベルで遺伝子発現のダイナミクスの分析.
主要な成果:
- 中間の誘導体濃度で,細胞はバイモダル型フェノタイプを示した:高と低の浸透酵素発現.
- 基礎レベルの発現は,DNAからの乳糖抑制体の部分解離と関連しています.
- めったに起こらない,完全な抑制剤解離イベントは,大爆発の浸透性発現を引き起こし,誘導を誘発しました.
結論:
- ラックオペロンにおけるフェノタイプのスイッチングは,単一分子レベルでストキャスティックイベントによって引き起こされます.
- ラクトース抑制体の解離ダイナミクスは,細胞現象型を決定する.
- 単一のストキャスティックイベントは,細胞の遺伝子発現の運命を決定することができます.
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