人間の赤血球の循環時計
John S O'Neill1, Akhilesh B Reddy
1Department of Clinical Neurosciences, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK.
Nature
|January 29, 2011
まとめ
人間の赤血球は,日中リズムに転写は必要ないことを明らかにします. ペロキシレドキシン・レドックスサイクルのような非転写メカニズムは,細胞の昼夜時計を維持し,既存のモデルに挑戦します.
科学分野:
- バイオケミストリー バイオケミストリー
- クロノバイオロジー クロノバイオロジー
- 細胞生物学 細胞生物学
背景:
- シルカディアンクロックは,様々な生物の生理学的プロセスを調節する.
- 現在の哺乳類モデルは,転写-翻訳フィードバックループに依存しています.
- 哺乳類における非転写的なクロックメカニズムを研究することは,大変な課題です.
研究 の 目的:
- 人間の細胞における昼夜リズムの非転写的メカニズムを調査する.
- 細胞の昼間振動にトランスクリプションが不可欠であるかどうかを判断する.
- 昼夜調節におけるペロキシレドキシンの役割を調査する.
主な方法:
- ヒトの赤血球 (核がない) を用いた新しい検査を開発した.
- 監視されたペロキシレドキシン・レドックスサイクルが,一定条件下で時間とともに変化します.
- 観察されたリズムの誘導性と温度補償を評価した.
主要な成果:
- ペロキシレドキシン・レドックスサイクルにおける日々の振動は,人間の赤血球で観察されました.
- これらのリズムは,外部のシグナルなしで何日も持続し,温度によって補償された.
- トランスクリプションは,これらの細胞の昼夜リズムを維持するために不要であることが判明しました.
結論:
- 非転写的イベントは,ヒトの細胞の昼夜リズムを維持するのに十分である.
- ペロキシレドキシン・レドックス・サイクルは,重要な非転写性昼夜的メカニズムを表しています.
- 発見は,真核生物の昼夜時計における非転写性振動のより広範な役割を示唆しています.
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