カゼインキナーゼ2αがドロソフィラの昼間時計に果たす役割
Jui-Ming Lin1, Valerie L Kilman, Kevin Keegan
1Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA.
Nature
|November 26, 2002
まとめ
カセインキナーゼ2 (CK2) は,Periodタンパク質をリン酸化し,ドロソフィラの昼夜リズムを調節する. CK2αααは,CK2ααααααααααααααααααααααααααααααααと一致する.
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:
- シルカディアンクロックは,転写フィードバックループを通じてリズム的行動を調節する.
- リン酸化を含む翻訳後の改変は,昼間の時計のタイミングにとって極めて重要です.
- Doubletime (Dbt) やShaggy (Sgg) などの既知のキナーゼは,昼間のタンパク質PerとTimを修正しますが,証拠は他のキナーゼが関与していることを示唆しています.
研究 の 目的:
- 昼夜リズムの調節におけるドロソフィラカゼインキナーゼ2 (CK2alpha) の役割を調査する.
- CK2alphaが昼間時計の成分を直接リン酸化するかどうかを判断する.
主な方法:
- 発生したCK2α変異のハエ.
- ミュータントのハエのサーカディアン周期の長さとCK2活性が評価された.
- 周期 (Per) タンパク質の核エントリを調べました.
- CK2alphaとPer.を使用した in vitro リン酸化アッセイを実施しました.
主要な成果:
- CK2alphaミュータントのハエは,長期にわたる昼夜周期を示した.
- 変異したハエは,全体的なCK2活性が低下したことを示した.
- CK2alpha変異体では,Periodタンパク質の核入りが遅れた.
- CK2alphaは,Perタンパク質をin vitroで直接リン酸化した.
結論:
- ドロソフィラCK2alphaは,昼夜リズムを調節する上で重要な役割を果たしています.
- CK2alphaは,Periodタンパク質を直接リン酸化し,その核の局所化と昼間のタイミングに影響を与えます.
- CK2は,多様な昼夜系の間の進化的リンクを代表する可能性がある.
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