相关实验视频
Updated: Aug 16, 2026

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Measuring the Kinetics of mRNA Transcription in Single Living Cells
Published on: August 25, 2011
转录延长的不连续机制
E Nudler1, A Goldfarb, M Kashlev
1Public Health Research Institute, New York, NY 10016.
概括
大肠杆菌中的RNA聚合酶在转录延长过程中以两种不同的方式移动. 它在平滑运动和虫类步骤之间移动,受DNA序列的影响,以管理内部应变.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 转录延长是基因表达的一个基本过程.
- RNA聚合酶 (RNAP) 是负责从DNA模板中合成RNA的酶.
- 了解RNAP动态对于破译基因调节至关重要.
研究的目的:
- 为了研究转录延长期间RNA聚合酶的动态运动.
- 为了确定DNA序列如何影响RNAP构造和运动.
- 在不同的DNA序列背景下阐明转录的机制.
主要方法:
- 研究了大肠杆菌中RNA聚合酶的运动.
- 观察了酶的三个灵活连接的部分:前端域,催化部位和RNA产品结合部位.
- 在不同DNA位点的延长过程中分析了构造变化和内部应变.
主要成果:
- 在长时间的转录段中,RNA聚合酶保持一致的形状.
- 特定的DNA位点可以暂时定前端域,诱导循环转移.
- 这导致了单调和虫般的交替运动模式.
- 在这些轮班期间,内部压力会积累并释放出来.
结论:
- 转录延长不是一个统一的过程,而是涉及不同的运动模式.
- RNA聚合酶的灵活配置是由DNA序列直接控制的.
- 这种依赖序列的机制使酶能够有效地导航DNA模板并管理内部应变.
相关概念视频
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
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...
Transcription Elongation Factors
Transcription elongation is a dynamic process that alters depending upon the sequence heterogeneity of the DNA being transcribed. Hence, it is not surprising that the elongation complex's composition also varies along the way while transcribing a gene.
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
The transcription elongation is regulated via pausing of RNA polymerase on several occasions during transcription. In bacteria, these halts are necessary because the transcription of DNA into mRNA is coupled to the translation of that mRNA into a...
Transcription in Prokaryotes
Transcription is a highly regulated process that converts genetic information into RNA molecules. The transcription cycle is divided into three key stages: initiation, elongation, and termination, each driven by specific molecular mechanisms.Initiation of TranscriptionIn bacteria, transcription begins when the RNA polymerase core enzyme associates with a sigma factor to form a holoenzyme. For example, the E. coli sigma factor called σ70 forms a holoenzyme, which recognizes the -10 (Pribnow box)...

