哺乳類のCry1とCry2は,昼夜リズムを維持するために不可欠です

G T van der Horst¹, M Muijtjens, K Kobayashi

¹MGC, Department of Cell Biology and Genetics, Erasmus University, Rotterdam, The Netherlands.

Nature

|April 27, 1999

まとめ

哺乳類の暗号染色体 (Cry1とCry2) は,昼夜リズムを維持するために不可欠です. これらのタンパク質が欠けているマウスは,生体時計を失います.

科学分野:

クロノバイオロジーはクロノバイオロジーを用います.
分子生物学は分子生物学である.
遺伝学遺伝学とは

背景:

シルカディアンリズムは,内部生物学的時計によって駆動される多数の生物学的プロセスを支配します.
分子時計は自己調節性遺伝子のフィードバックループに依存し,光によって太陽の日と同期されます.
哺乳類の暗号染色体 (Cry1とCry2) は,生物学的時計の光誘導のための潜在的な光受容体である.

研究の目的:

ネズミにおける日中リズムの光学訓練と維持におけるCry1およびCry2タンパク質の役割を調査する.
Cry1とCry2が生物学的時計の内部タイムキーピングに不可欠であるかどうかを判断する.

主な方法:

マウスでの遺伝子ノックアウト研究で,Cry1欠乏症およびCry2欠乏症モデルを生成する.
常時条件下における野生型および変異性マウスの運動運動リズム分析.
Cry1および/またはCry2.2の欠如における昼夜リズム性のフェノタイプ的特徴づけ

主要な成果:

Cry1が欠けていたマウスは,運動運動の加速された自由走行周期を示した.
Cry2が欠けていたマウスは,運動運動の自由走行周期が遅れたことを示した.
Cry1とCry2の両方が欠けていたマウスは,自由走行のリズム性を完全に失い,瞬時に失いました.

結論:

Cry1とCry2のタンパク質は,哺乳類の昼夜リズムを維持するために不可欠です.
これらの暗号染色体は,潜在的光受容を超えて重要な役割を果たし,原子核の分子時計機構に直接影響を及ぼします.
Cry1とCry2の両方の欠如は,リズムを維持する生物学的時計の能力を深刻に破壊します.

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