通过CRP激活转录的严格间距要求
1Unité de Physicochimie des Macromolécules Biologiques, URA 1149 du CNRS, Institut Pasteur, Paris, France.
Cell
|August 24, 1990
概括
循环AMP受体蛋白-cAMP复合体 (CRP-cAMP) 从特定的DNA位置激活大肠杆菌的转录. 这项研究揭示了一个双位置激活模型,对于理解基因调节至关重要.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 循环AMP受体蛋白-cAMP复合体 (CRP-cAMP) 是大肠杆菌中一个关键的转录激活剂.
- 结合CRP-cAMP的结合部位位置会影响转录激活的效率.
研究的目的:
- 为了研究CRP-cAMP结合点距离对melR促进体转录的影响.
- 为了确定CRP-cAMP是否表现出特定的位置偏好来激活.
主要方法:
- 构建一个合成促进体系统,在melR促进体上游的不同距离处有CRP结合点.
- DNase I足迹测试用于评估RNA聚合酶和CRP-cAMP相互作用.
- 在体外运动分析以测量转录激活率.
主要成果:
- 当CRP-cAMP在特定距离上结合时,会激活melR促进体的转录,所有这些都是在DNA螺旋的同一面上.
- 最佳激活距离与在大肠杆菌galP1和lac促进者中观察到的距离相符.
- 不管CRP-cAMP结合距离如何,RNA聚合酶与-10区域的接触是相同的.
结论:
- 通过CRP-cAMP介导的转录激活取决于位置,有利于特定的螺旋位置.
- 一个双位置激活模型解释了观察到的现象,强调了DNA循环和蛋白质-DNA相互作用的重要性.
相关概念视频
Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
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...
CRISPR and crRNAs
Bacteria and archaea are susceptible to viral infections just like eukaryotes; therefore, they have developed a unique adaptive immune system to protect themselves. Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins (CRISPR-Cas) are present in more than 45% of known bacteria and 90% of known archaea.
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
Transcription Initiation
Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription.
The promoters and enhancers and their accessory proteins allow tight regulation of...
The promoters and enhancers and their accessory proteins allow tight regulation of...
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...


