アラビドプシスの昼間時計には,cADPRベースのフィードバックループが組み込まれています
Antony N Dodd1, Michael J Gardner, Carlos T Hotta
1Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
Science (New York, N.Y.)
|December 18, 2007
まとめ
植物の昼間時計は,循環性アデノシン二酸化リボース (cADPR) を使用して,その転写フィードバックループを調節します. この信号分子は,カルシウム振動を駆動し,時計内の新しいフィードバックメカニズムを形成します.
科学分野:
- 植物生物学 植物生物学
- クロノバイオロジー クロノバイオロジー
- 分子シグナル伝達です.
背景:
- 植物や動物の日経時計は,転写的なフィードバックループに依存しています.
- 植物の日常リズムにおける細胞細胞シグナル伝達分子の役割は完全に理解されていません.
研究 の 目的:
- 循環性アデノシン二酸化リボース (cADPR) が植物の昼夜時計に関与するかを調査する.
- cADPRが転写フィードバックループを調節し,カルシウム振動に影響を与えるかどうかを判断する.
主な方法:
- cADPRシグナル伝達の使用された抗体.
- 操作されたcADPR合成経路.
- 数学的シミュレーションを用いて,cADPR-サーカディアンクロックの相互作用をモデル化しました.
主要な成果:
- cADPRが昼間振動器の転写フィードバックループを調節することを実証した.
- cADPRが細胞塩酸カルシウム (Ca2+) の放出における昼間振動を誘導することを示した.
- 証拠によると,cADPRは,植物の昼間時計の中で統合されたフィードバックループを形成している.
結論:
- cADPRは,植物の昼間時計の重要な構成要素である.
- cADPRシグナリングは,日中リズムにおける転写調節とカルシウム動態の両方に影響を与える.
- この研究は,植物の時間測定にcADPRを伴う新しいフィードバックメカニズムを明らかにしています.
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