来自Bacillus subtilis的两个RNA聚合酶西格玛因子区分一个发育调节基因的重叠促进体
Nature
|April 28, 1983
概括
研究人员发现了一种新的sigma因子 (sigma32),可以控制Bacillus subtilis中的特定基因 (spoVG). 这一发现揭示了不同的西格玛因子如何调节细菌基因表达.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 细菌遗传学 细菌遗传学
背景情况:
- 细菌细菌 spoVG 基因在发育上受到调节.
- 基因表达是由重叠的促进体和RNA聚合酶西格玛因子控制的.
- 众所周知,Sigma 37可以调节spoVG的上游促进体.
研究的目的:
- 识别和描述负责调节 spoVG 基因下游促进者的西格玛因子.
- 阐明Bacillus subtilis在西格玛特异性促进体识别的机制.
主要方法:
- 一个新的西格玛因子的隔离和特征.
- 从spoVG基因进行转录启动的分析.
- 开发一个特定于Sigma的促进者识别模型.
主要成果:
- 隔离了32,000个分子重量的西格玛因子 (sigma 32).
- 西格玛32只从下游的spoVG促进器指导转录启动.
- 为 spoVG 转录启动区域内交织的西格玛特异性识别序列提出了一个模型.
结论:
- 西格玛32是一种独特的西格玛因子,专门调节spoVG基因的下游促进体.
- 这些发现为通过多个西格玛因子对细菌基因表达的复杂调节提供了洞察力.
- 这项研究提出了一个模型,说明不同的西格玛因子如何识别重叠的促进子序列.
相关概念视频
Bacterial RNA Polymerase
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
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...
Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
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...
Bacterial RNA Polymerase
Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
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...


