在Drosophila的昼夜时钟中,素激酶2alpha的作用
Jui-Ming Lin1, Valerie L Kilman, Kevin Keegan
1Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois 60208, USA.
Nature
|November 26, 2002
概括
素激酶2 (CK2) 酸化周期蛋白,调节Drosophila的昼夜节律. 在CK2alpha中使用.
科学领域:
- 时间生物学 时间生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 循环时钟通过转录反循环来调节节律态行为.
- 翻译后的修改,包括酸化,对于昼夜时钟计时至关重要.
- 已知的激酶如Doubletime (Dbt) 和Shaggy (Sgg) 修改昼夜蛋白质Per和Tim,但证据表明其他激酶也参与其中.
研究的目的:
- 为了研究多索菲拉素酶2 (CK2alpha) 在昼夜节律调节中的作用.
- 为了确定CK2alpha是否直接酸化昼夜时钟组件.
主要方法:
- 产生了CK2alpha突变的.
- 在突变中评估昼夜周期长度和CK2活性.
- 检查了周期 (Per) 蛋白的核输入.
- 使用CK2alpha和Per进行了体外酸化试验.
主要成果:
- CK2alpha突变的表现出延长的昼夜周期.
- 突变的显示出整体CK2活性下降.
- 在CK2alpha突变体中,周期蛋白的核进入被延迟.
- 在实验室中,CK2alpha直接化了Per蛋白.
结论:
- 草CK2alpha在调节昼夜节律方面发挥着重要作用.
- CK2alpha直接酸化Period蛋白,影响其核定位和昼夜时间.
- CK2可能代表着不同昼夜系统之间的进化联系.
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