相关实验视频
Updated: Jun 21, 2026

06:59
Nanomanipulation of Single RNA Molecules by Optical Tweezers
Published on: August 20, 2014
通过一个与新生RNA毛接触的部位对RNA聚合酶进行全身控制
I Toulokhonov1, I Artsimovitch, R Landick
1Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA.
概括
一种调节蛋白 (NusA) 和RNA聚合酶 (RNAP) 与RNA发针相互作用,以控制基因表达. 这种三方相互作用以全性方式抑制转录,揭示了调节基因活性的新机制.
科学领域:
- 分子生物学分子生物学
- 基因表达规范 基因表达规范
- 生物化学 生物化学
背景情况:
- 基因表达受到DNA,RNA和与RNA聚合酶 (RNAP) 相互作用的调节分子的严格调节.
- 了解转录调节的精确机制对于破译细胞过程和开发治疗策略至关重要.
研究的目的:
- 阐明特定RNA结构和调节蛋白NusaA与RNAP相互作用以调节转录的分子机制.
- 为了研究RNAP的尖螺旋在调节 NusA 和调节性RNA毛的存在下对转录延长的作用.
主要方法:
- 蛋白质-RNA交叉链接实验以确定直接相互作用.
- 分子建模以可视化复杂并预测相互作用接口.
- 对RNAP和RNA突变的分析,以评估对转录的功能影响.
主要成果:
- 在RNAP的膜域的尖端,一个短的α螺旋线直接接触到新生的RNA发针结构.
- 这种顶螺旋对于调节蛋白Nusa的活性至关重要.
- 一个涉及RNAP,NusaA和RNA发针的三方复合体抑制了位于远部位的活性部位的核酸添加.
结论:
- 这些发现支持了对转录延长调节的全模型.
- 这种机制突出了通过RNAP,调节蛋白和RNA结构之间的协调相互作用来控制基因表达的新途径.
相关概念视频
RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
pre-mRNA Processing
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Eukaryotic RNA Polymerases
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All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
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:
Types of RNA
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in regulating gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA Performs Diverse...
RNA Performs Diverse...
Nucleic Acid Structure
The pentose sugar in DNA is deoxyribose, while in RNA the pentose sugar is ribose. The difference between the sugars is the presence of the hydroxyl group on the ribose's second carbon and a hydrogen on the deoxyribose's second carbon. The phosphate residue attaches to the hydroxyl group of the 5′ carbon of one sugar and the hydroxyl group of the 3′ carbon of the sugar of the next nucleotide, which forms a 5′ to 3′ phosphodiester linkage.
DNA Structure
DNA has a double-helix structure. The...
DNA Structure
DNA has a double-helix structure. The...

