クリプトクローム:植物や動物の青い光の受容体
A R Cashmore1, J A Jarillo, Y J Wu
1Plant Science Institute, Department of Biology, University of Pennsylvania, Philadelphia, PA 19104-6018, USA. cashmore@upenn.sas.edu
まとめ
植物で広く見られる青光光受容体である暗号クロームは,昼夜リズムを調節する. 植物と動物の暗号クロームは別々に進化し,動物のバージョンは最近,改変された昼夜時計と共に現れました.
科学分野:
- バイオケミストリー バイオケミストリー
- 分子生物学は分子生物学である.
- 進化生物学の進化生物学について
背景:
- クリプトクロームは青色で,紫外線-Aの光の光受容体である.
- それらは,進化的にフォトリアゼに関連したフラボタンパク質である.
- クリプトクロームは,藻類からアラビドプシス (Arabidopsis) まで,植物のいたるところに存在します.
研究 の 目的:
- クリプトクロームの進化史と機能を調査する.
- 植物と動物の暗号クロームファミリーを比較するために.
- シルカディアンリズムにおける暗号染色体の役割を理解する.
主な方法:
- 植物と動物の暗号染色体の配列比較.
- アラビドプシスやドロソフィラのようなモデル生物における暗号色機能の分析.
- 暗号染色体と日中時計タンパク質の関係を調査する.
主要な成果:
- 植物と動物の暗号クロームファミリーは,異なる進化の歴史を持っています.
- 植物の暗号クロームは古代の起源であるが,動物の暗号クロームは最近進化した.
- クリプトクロームは,様々な種において,昼夜リズムを牽引するなど,光の反応を媒介する.
結論:
- クリプトクロームは,光知覚と全領域の昼夜調節において重要な役割を果たします.
- 植物と動物の暗号染色体の独立した進化は,収束進化を強調しています.
- 動物の暗号染色体の最近の進化は,新しい昼夜時計のメカニズムの出現と関連している可能性があります.
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