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循环Vrille表达对于一个功能性的Drosophila时钟是必要的
1Laboratory of Genetics, The Rockefeller University, New York, New York 10021, USA.
Cell
|December 28, 1999
概括
研究人员在Drosophila中发现了一个新的反循环.
科学领域:
- 时间生物学 时间生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 昼夜节律是内生生物过程,调节睡眠-清醒周期和其他生理功能.
- 果Drosophila melanogaster作为研究昼夜时钟机制的模型生物.
- 时钟控制的基因在生物过程的时间调节中起着至关重要的作用.
研究的目的:
- 为了确定Drosophila昼夜钟的新组件和调节机制.
- 调查弗里尔 (vri) 基因在昼夜节律中的作用.
- 为了阐明弗里和其他已知的时钟基因之间的关系.
主要方法:
- 在Drosophila中进行了对时钟控制基因的选.
- 利用RNA分析来测量基因表达水平.
- 进行基因操纵来评估Vrille的功能.
- 在果中观察到的行为节奏.
主要成果:
- 确定了转录因子vrille (vri),作为一个时钟控制的基因.
- 证明vriRNA水平与昼夜节律振荡,由dCLOCK和CYCLE调节.
- 表明,自由循环对于时期和永恒基因的表达至关重要.
- 发现,失去自由循环会导致行为节律的改变,包括长时间和失节.
- 揭示了dCLOCK和VRI都独立调节色素分散因子 (PDF).
结论:
- 在Drosophila的昼夜钟中发现了一种涉及Vrille的新型调节循环.
- 骑自行车Vrille对于保持Drosophila昼夜时钟的正常运行至关重要.
- 弗里尔基因与dCLOCK一起影响神经色素分散因子,影响明显的行为.
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