Related Experiment Video
Updated: Jun 16, 2026
10:59
Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events
Published on: May 13, 2019
Processivity and coupling in messenger RNA transcription.
Stuart Aitken1, Marie-Cécile Robert, Ross D Alexander
1Centre for Systems Biology, University of Edinburgh, Edinburgh, United Kingdom. s.aitken@ed.ac.uk
Plos One
|February 4, 2010
Summary
This study reveals that detailed modeling of messenger RNA (mRNA) elongation, considering processivity versus promoter coupling, significantly impacts mRNA distribution predictions. These findings refine our understanding of gene expression dynamics.
Area of Science:
- Molecular Biology
- Biophysics
- Systems Biology
Background:
- Advanced experimental techniques reveal the complexity of messenger RNA (mRNA) processing and kinetics.
- Current models often simplify active transcription into a single on/off promoter state, omitting detailed processes like elongation.
- Existing models fail to capture the minimum time for elongation completion and associated processing events.
Purpose of the Study:
- To investigate the impact of detailed mRNA elongation modeling on mRNA distribution.
- To compare two alternative models of polymerase-promoter coupling: processivity and coupling.
- To assess the influence of these models on predicted mRNA distributions and cellular noise.
Main Methods:
- Development and simulation of two distinct models for mRNA elongation: processivity and promoter coupling.
- Utilizing the Gillespie algorithm for model simulation.
- Computation of the third and fourth moments of the mRNA distribution to characterize peak sharpness and tail length.
Main Results:
- The choice between processivity and promoter coupling models significantly alters predicted mRNA distributions.
- Statistical moments (third and fourth) provide a concise and sensitive summary of distribution characteristics.
- Statistically significant differences in distribution moments were observed across a wide parameter range.
Conclusions:
- The simple on/off model is inconsistent with observed processivity unless elongation success probability is low.
- Promoter-polymerase coupling may explain the cell's limited ability to maintain high mRNA levels with low noise.
- Refined models incorporating detailed elongation mechanisms are crucial for accurately predicting mRNA dynamics and gene expression noise.
Related Concept Videos
02:41Chromatin Structure Regulates pre-mRNA Processing
In eukaryotic cells, nascent mRNA transcripts need to undergo many post-transcriptional modifications to reach the cell cytoplasm and translate into functional proteins. For a long time, transcription and pre-mRNA processing were considered two independent events that occur sequentially in the cell. However, it has now been well established that transcription and pre-mRNA processing are two simultaneous processes that are precisely regulated inside the cell.
The chromatin structure, especially...
The chromatin structure, especially...
02:01pre-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...
02:01Pre-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...
01:35Pre-mRNA Processing: Modification of pre-mRNA Ends
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 (7-methyl guanosine). This 5' cap helps the cell...
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 (7-methyl guanosine). This 5' cap helps the cell...
01:53Bacterial 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:
01:10Transcription
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...