来自Drosophila的变形自调节元件在转基因小鼠中以保守的方式起作用
1Medical University of South Carolina, Department of Biochemistry and Molecular Biology, Charleston 29425.
Nature
|July 23, 1992
概括
来自果的变形 (Dfd) 基因增强剂可以在小鼠胚胎中驱动基因表达,揭示身体轴发育的保存机制. 这一发现突显了物种之间共同的遗传调节,以建立位置性身份.
科学领域:
- 发展生物学 发展生物学
- 遗传学 遗传学 是一个
- 进化生物学 进化生物学
背景情况:
- 鼠的Hox基因和Drosophila同源基因复合体 (HOM-C) 在结构和表达上有相似之处.
- 在小鼠和胚胎中,基因组的Hox/HOM基因顺序和它们的前后表达域之间存在保存的直线性.
- 对精确的Hox/HOM基因表达模式而言,Cis调节元素至关重要.
研究的目的:
- 在哺乳动物系统中研究Drosophila Deformed (Dfd) 自律增强剂的保存功能.
- 为了确定DFD增强剂是否可以在小鼠胚胎中赋予特定区域的表达.
- 为了探索前后轴规格的保存机制.
主要方法:
- 转基因小鼠胚胎的生成.
- 使用来自Drosophila的Dfd自我调节增强剂.
- 评估特定胚胎区域的记者基因表达.
主要成果:
- Dfd自我调节增强剂成功地将记者基因表达赋予了小鼠后脑的一个离散子区域.
- 鼠标胚胎中的这种表达域与相似的霍克斯基因的前后表达域相对应.
- 增强剂的活性在不同物种中保持不变,以类似的前后方式运行.
结论:
- Dfd自我调节增强剂是一种高度保守的调节元素.
- 这种增强剂在建立沿前后轴区域特异性基因表达的保存机制中发挥作用.
- 这些发现支持了保留机制的概念,用于确定胚胎发育中的位置性身份.
相关概念视频
02:32Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
02:45The Ratio of X Chromosome to Autosomes
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
02:50Dosage Compensation
In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one Y chromosome, whereas C.elegans with one X chromosome is a male, and the one with two X chromosomes is a hermaphrodite.
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...