能量代谢中的光驱动的变化直接触发了蓝藻细菌的昼夜振荡器
Michael J Rust1, Susan S Golden, Erin K O'Shea
1Howard Hughes Medical Institute, Center for Systems Biology, Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
概括
蓝藻细菌的昼夜时钟是通过变化三酸氨酸 (ATP) 和二酸氨酸 (ADP) 水平的光线线引进的. ADP抑制了激酶活性,为昼夜时钟的携带提供了定量解释.
科学领域:
- 生物振荡器的分子机制
- 在 prokaryotes 中循环节律.
- 细胞过程的生物化学调节.
背景情况:
- 循环时钟表现出自我维持的振荡,并响应环境线索.
- 昼夜时钟的分子基础尚未完全理解.
- 菌具有对光敏感的昼夜时钟.
研究的目的:
- 阐明在蓝藻细菌中昼夜时钟引入的基础分子机制.
- 研究腺三酸盐 (ATP) 和腺二酸盐 (ADP) 在昼夜节律调节中的作用.
- 为了确定核酸比率的变化是否可以解释体内相位变化.
主要方法:
- 在实验室中使用三种蓝藻细菌蛋白和ATP重建昼夜振荡.
- 监测ATP/ADP比率的变化,以应对培养的蓝藻细菌中的光转移.
- 在体外振荡器模型中模拟观察到的核酸变化.
- 开发由实验数据所限制的数学模型.
主要成果:
- 一个复制的体外振荡器显示了酸化中的振荡.
- 在体内因光引起的相位变化与改变的ATP/ADP比率相关.
- 在体外系统中模拟这些ATP/ADP变化,在体外系统中复制体内相位变化.
- 发现腺二酸盐 (ADP) 抑制了振荡器中的激酶活性.
结论:
- ATP/ADP比率的变化是蓝藻细菌中昼夜时钟的关键机制.
- 腺二酸盐 (ADP) 在昼夜振荡器中作为激酶活性的直接抑制剂.
- 描述的分子机制量化地解释了蓝藻细菌昼夜时钟被光所吸引的原因.
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