草虫的时钟可以产生宫外昼夜时钟
Jie Zhao1, Valerie L Kilman, Kevin P Keegan
1Howard Hughes Medical Institute, Department of Biology, Brandeis University, Waltham, MA 02454, USA.
Cell
|June 18, 2003
概括
转录激活器时钟诱导昼夜基因表达并改变Drosophila的行为. 在天真的大脑区域中,时钟的错误表达组织了对于昼夜节律至关重要的核心反循环.
科学领域:
- 时间生物学 时间生物学
- 分子生物学分子生物学
- 神经遗传学 神经遗传学
背景情况:
- 循环节律控制着生物体内的行为,生理和基因表达的日常周期.
- 转录激活器时钟对于果 (Drosophila) 和哺乳动物的核心时钟基因表达至关重要.
研究的目的:
- 为了研究时钟误表在诱导昼夜基因表达和Drosophila的行为变化中的作用.
- 为了确定"时钟"能否组织为昼夜节律提供必要的反循环.
主要方法:
- 作为一个模型生物体的Drosophila melanogaster.
- 在天真的大脑区域中,钟基因的遗传错误表达.
- 对昼夜基因表达模式的分析.
- 运动运动活动的观察和量化.
主要成果:
- 在天真的大脑区域中错误表达时钟诱导了昼夜基因表达,包括关键的起器组件.
- 时钟激活了加密染色体的节奏表达,这种基因通常被CLOCK抑制.
- 外阴时钟表达显著改变了运动活动模式,显示出强大的行为效应.
结论:
- 时钟具有独特的能力,可以诱导和组织昼夜节律所需的相互依存的反循环的核心元素.
- 时钟作为一个主调节器,能够在以前不节律的组织中启动昼夜输出.
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