相关实验视频
Updated: May 10, 2026

11:41
Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
在扭力下转录
Jie Ma1, Lu Bai, Michelle D Wang
1Department of Physics-Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA.
概括
这项研究揭示了RNA聚合酶 (RNAP) 如何导航超绕的DNA. RNAP充当一个强大的电机,管理扭矩来调节转录,即使停滞.
科学领域:
- 分子生物学分子生物学
- 生物物理学的生物物理.
背景情况:
- 细胞通过不断变化的扭转状态转录超绕的DNA.
- 通过RNA聚合酶 (RNAP) 处理DNA超级卷的机制尚未完全理解.
研究的目的:
- 为了研究单个大肠杆菌RNAP如何与超级卷DNA相互作用和转录.
- 量化RNAP在转录过程中产生的和管理的扭矩.
主要方法:
- 直接测量单个埃舍里希亚大肠杆菌RNAP的转录超卷DNA.
- 在不同的扭矩条件下分析RNAP速度,暂停频率和持续时间.
主要成果:
- 抗拒扭矩显著减缓了RNAP,增加了暂停频率和持续时间.
- 在停滞之前,RNAP产生了11 ± 4 piconewton-nanometers的平均扭矩,足以使DNA化.
- 停滞的RNAP可以在扭矩放松时恢复转录,证明对波动的弹性.
结论:
- RNAP作为一种强大的扭矩电机,能够在转录过程中管理显著的扭矩.
- 动态DNA超级卷是转录的关键调节器,RNAP积极适应扭曲应力.
- 这些发现为了解通过DNA超级卷的转录调节提供了定量框架.
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 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...
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)...
Transcription
Transcription is the synthesis of RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in correctly synthesizing messenger RNA (mRNA). Transcriptional regulation is responsible for the differentiation of different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds of RNA Molecules
In eukaryotes,...
Transcription Can Produce Different Kinds of RNA Molecules
In eukaryotes,...
Transcription
Overview
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds...
Transcription is the process of synthesizing RNA from a DNA sequence by RNA polymerase. It is the first step in producing a protein from a gene sequence. Additionally, many other proteins and regulatory sequences are involved in the proper synthesis of messenger RNA (mRNA). Regulation of transcription is responsible for the differentiation of all the different types of cells and often for the proper cellular response to environmental signals.
Transcription Can Produce Different Kinds...

