相关实验视频
Updated: Jun 29, 2025
07:12
Circadian Entrainment of Drosophila Melanogaster
Published on: June 3, 2020
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无时无刻的非编码DNA含有细胞类型优先增强剂,这对于适当的Drosophila昼夜调节至关重要
Dingbang Ma1,2, Pranav Ojha3,4, Albert D Yu3,4
1Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 201210, China.
概括
在Drosophila无时代基因中的CRISPR删除揭示了上游增强剂对于整体时钟基因表达至关重要. 然而,一个内部增强剂.
科学领域:
- 遗传学 是一个遗传学.
- 时间生物学 时间生物学
- 分子生物学分子生物学
背景情况:
- 转录调节显著影响多虫钟基因表达和行为.
- 无时代 (tim) 基因是Drosophila昼夜钟的关键组成部分.
- 电子盒区域是通过像Clock (Clk) 和Cycle这样的转录因子识别的关键调节元素.
研究的目的:
- 研究Drosophila无时代 (tim) 基因内特定调节区域在控制其表达中的作用.
- 确定内部和上游E-box区域对时间表达和昼夜行为的贡献.
- 阐明Drosophila时钟神经元中细胞类型特定的调节机制.
主要方法:
- 使用CRISPR介导的基因编辑来创建时间基因的内部和上游E盒区域的删除.
- 在头中对timRNA和TIM蛋白水平的定量分析.
- 评估其他时钟基因的循环幅度.
- ATAC-seq (测定转化酶可访问的染色质与测序) 在纯化的神经元和神经细胞上进行.
主要成果:
- 上游删除,但不是内部删除,在飞头中显著减少了时间表达和循环幅度.
- 最大的上游删除将峰值时间RNA水平降低到正常水平的15%,同样影响了TIM蛋白水平.
- 其他时钟基因循环幅度因低谷水平增加而减少.
- 与整个头相比,时钟神经元中的时间表达受到上游删除的影响较小,内部区域的删除在神经元中具有类似的影响.
- ATAC-seq揭示了内部增强器区域的增强可访问性,特别是在时钟神经元内.
结论:
- 上游的E-box增强器区域在调节Drosophila头的时间表达方面发挥着重要作用.
- TIM蛋白质有助于时钟基因的转录抑制.
- 时钟神经元中内基增强剂的增强可访问性解释了时间表达和昼夜行为对上游调控区域删除的细胞类型特异性弹性.
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