在 prokaryotic 增强体受体因子 sigma 54 中发现的真核类型功能域的作用
1Department of Chemistry and Biochemistry, University of California, Los Angeles 90024.
Cell
|September 7, 1990
概括
大肠杆菌西格玛54蛋白质是E.
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:
- 大肠杆菌sigma 54蛋白对于基因转录的启动至关重要.
- 它能够从遥远的DNA位点激活促进子,这是一个独特的调节机制.
- 了解其功能领域是解读其监管作用的关键.
研究的目的:
- 研究大肠杆菌西格玛54蛋白的不同功能域的作用.
- 阐明这些域如何促进促进体识别,DNA化和远程激活.
- 了解西格玛54在转录调节中的结构功能关系.
主要方法:
- 局部导向的突变发生来破坏西格玛54蛋白的特定功能域.
- 在体内足迹测试测试以探测转录复合体的组装.
- 促进体识别,闭合体形成和DNA化的分析.
主要成果:
- 促进器的识别取决于一个C端螺旋旋转螺旋形象.
- 氨酸拉链图案对于将聚合酶定位在封闭复合体中至关重要.
- 西格玛54的酸性域是DNA融化和开放所必需的.
结论:
- 西格玛54蛋白质的模块化域结构允许从DNA融中解离促进体识别.
- 这种域组织对于从遥远的DNA位点中调解转录激活至关重要.
- 这些发现提供了关于西格玛54转录因子独特的调控能力的见解.
相关概念视频
Prokaryotic cells
Prokaryotes are small unicellular organisms that include the domains—Archaea and Bacteria. Bacteria include many common organisms, such as Salmonella and E. coli, while the Archaea include extremophiles that live in harsh environments, such as volcanic springs.
Like eukaryotic cells, all prokaryotic cells are surrounded by a plasma membrane, have genetic material in the form of single, circular DNA, a cytoplasm that fills the interior of the cell, and ribosomes that synthesize proteins.
Like eukaryotic cells, all prokaryotic cells are surrounded by a plasma membrane, have genetic material in the form of single, circular DNA, a cytoplasm that fills the interior of the cell, and ribosomes that synthesize proteins.
Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...
Riboswitches
Riboswitches are non-coding mRNA domains that regulate the transcription and translation of downstream genes without the help of proteins. Riboswitches bind directly to a metabolite and can form unique stem-loop or hairpin structures in response to the amount of the metabolite present. They have two distinct regions – a metabolite-binding aptamer and an expression platform.
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
Prokaryotic Transcriptional Activators and Repressors
The organization of prokaryotic genes in their genome is notably different from that of eukaryotes. Prokaryotic genes are organized, such that the genes for proteins involved in the same biochemical process or function are located together in groups. This group of genes, along with their regulatory elements, are collectively known as an operon. The functional genes in an operon are transcribed together to give a single strand of mRNA known as polycistronic mRNA.
Transcription of prokaryotic...
Transcription of prokaryotic...


