精氨酸抑制剂通过核心压缩剂介导的特定DNA结合的机制
M A Schumacher1, K Y Choi, F Lu
1Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland 97201-3098, USA.
Cell
|October 6, 1995
概括
小分子效应器调节DNA结合蛋白的亲和力. 移除核心压缩器会导致 purin 压缩器.
科学领域:
- 结构生物学 结构生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 小分子效应器通常调节 prokaryotes 和 eukaryotes 中的 DNA 结合蛋白亲和力.
- 远端蛋白质域对DNA结合的效应因子诱导的全调节机制在结构上仍然不太了解.
研究的目的:
- 阐明在氨酸抑制剂中受效器调节的DNA结合的结构机制.
- 了解核心压缩剂结合如何影响这种压缩剂家族中的DNA相互作用.
主要方法:
- 在初步研究中确定了与核心压缩机和purF运算机结合的纯氨酸抑制器的晶体结构.
- 在2.2 Å分辨率下确定了纯氨酸抑制器的无核心压缩机核心压缩机结合域的晶体结构.
主要成果:
- 结构分析显示,核心压力结合口袋在未结合状态下发生了显著的形状变化.
- 每个子单元在移除核心压缩机后旋转开放高达23度.
- 这种旋转解开了小沟结合链螺旋,导致抑制剂-DNA解离.
结论:
- 精氨酸抑制剂在核心压缩剂结合和释放时经历了实质性的形状变化.
- 通过大规模的域移动来调节DNA结合的Allosteric调节.
- 这为理解抑制器中效应器调节的DNA结合提供了结构基础.
相关概念视频
RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
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...
Eukaryotic Transcription Inhibitors
Certain biochemical processes, such as embryonic development and cell growth regulation, depend on the repression of specific genes. DNA binding proteins known as eukaryotic transcription inhibitors regulate the repression of gene expression in eukaryotes. The presence of these inhibitors at the required location and time in the cell is triggered by the presence of hormones and additional signals from other cells.
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
Eukaryotic transcription inhibitors usually contain two distinct domains, a DNA...
Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
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...


