哺乳類の昼間ペースメーカーのコアコンポーネントとして,cAMPに依存したシグナル伝達
John S O'Neill1, Elizabeth S Maywood, Johanna E Chesham
1Medical Research Council (MRC) Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK.
まとめ
サイクルアデノシンモノフォスファート (cAMP) 信号伝達は,哺乳類の昼夜時計の新発見された構成要素である. このシグナル伝達経路は,コアトランスクリプションのフィードバックループを維持し,時計を保証します.
科学分野:
- クロノバイオロジー クロノバイオロジー
- 分子生物学は分子生物学である.
- 細胞シグナリング 細胞シグナリング
背景:
- 哺乳類の昼夜時計は,主に転写と転写後のフィードバックループとしてモデル化されています.
- 循環性遺伝子発現は,タンパク質産物による遺伝子の周期的な抑制によって調節される.
研究 の 目的:
- 周期性アデノシンモノフォスファート (cAMP) のシグナル伝達が哺乳類の昼夜時計で果たす役割を調査する.
- cAMPシグナリングが,確立された転写フィードバックモデルを超えた新しい規制メカニズムを表しているかどうかを判断する.
主な方法:
- 上核 (SCN) のリズム的なcAMPシグナル伝達の分析.
- SCNにおける転写ループ機能に対するcAMPシグナル伝達の影響を調査.
- 周辺哺乳類の組織と細胞系におけるcAMPシグナル伝達の役割の検討.
主要な成果:
- 周期性アデノシンモノフォスファート (cAMP) 信号は,哺乳類の昼夜時計のリズム的成分として識別されています.
- cAMPシグナル伝達は,上質核の転写ループを維持し,振幅,相,周期に影響を与えます.
- このcAMPの規制的役割は,異なる哺乳類の組織と細胞タイプにわたって保存されています.
結論:
- 周期性アデノシンモノフォスファート (cAMP) 信号伝達は,哺乳類の昼夜調節の重要な,以前は認識されていない要素である.
- この研究では,トランスクリプションオシレータによって誘発される毎日のcAMP活性化が,その後のトランスクリプションリズムを維持するモデルを提案しています.
- これは,時計の出力が将来のサイクルの入力として機能し,サーカディアンネットワークの理解を拡大する新しいメカニズムを強調しています.
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