在HoxD复合体中的基因转换揭示了监管控制的层次结构
F van der Hoeven1, J Zákány, D Duboule
1Department of Zoology and Animal Biology, University of Geneva, Switzerland.
Cell
|June 28, 1996
概括
脊椎动物的Hox基因表现出与它们的集群顺序相关的时间激活. 转移Hoxd基因揭示了共享的调节元素和新的干扰,表明高阶调节维持了Hox基因聚类.
科学领域:
- 发展生物学 发展生物学
- 遗传学 遗传学 是一个
- 分子生物学分子生物学
背景情况:
- 脊椎动物的霍克斯基因对发育至关重要,并被组织成群集.
- 霍克斯群中的基因激活通常遵循特定的时间和空间序列,与它们的线性排列相关联.
研究的目的:
- 调查控制霍克斯基因激活的调控机制.
- 为了确定基因序列和位于HoxD复合体内的位置的作用.
- 探索基因迁移如何影响表达模式和调控相互作用.
主要方法:
- 引入 lacZ 标记的 Hoxd 转录单元到 HoxD 综合体内的异胎 5' 位置.
- 分析不同发育阶段的转移基因的表达模式.
- 检查特定组织 (如四肢和生殖器突出部) 中的依赖位置的表达.
主要成果:
- 转移的Hoxd基因表现出延迟的早期表达,模仿邻近的Hoxd-13.
- 后来的阶段揭示了远端四肢和生殖器突出部位的位置依赖表达,表明共享的调节元素.
- 实验表明,邻近的基因可以共享cis作用序列,并且基因迁移会导致新的调节干扰.
结论:
- 高级调节机制控制霍克斯基因激活.
- 对于多个Hox基因,使用了共同的调节机制.
- 由于包括共享 cis 作用序列和调控干扰在内的约束因素,基因聚类得到保存.
相关概念视频
Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
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Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
Combinatorial Gene Control
Combinatorial gene control is the synergistic action of several transcriptional factors to regulate the expression of a single gene. The absence of one or more of these factors may lead to a significant difference in the level of gene expression or repression.
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
The expression of more than 30,000 genes is controlled by approximately 2000-3000 transcription factors. This is possible because a single transcription factor can recognize more than one regulatory sequence. The specificity in gene...
Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...


