JUN 06, 2021 9:29 AM PDT

Caught in the Act of RNA Transcription

WRITTEN BY: Carmen Leitch

As microscopy tools get better and better, scientists have been able to visualize structures on a smaller and smaller scale. Researchers have now been able to capture an enzyme called RNA polymerase as it carries out one of life's most essential processes: the copying of a DNA sequence into an RNA molecule that can be used by the cell to make protein, for example. For the first time, researchers have seen the process of transcription as it starts, at the level of an individual gene. The findings have been reported in Nature Communications.

"This is the first time someone has looked at RNA polymerase phosphorylation dynamics in a single-copy gene," said study leader and postdoctoral researcher Linda Forero-Quintero Forero, Ph.D. of Colorado State University.

At one time, researchers studying transcription used models called gene arrays, in which hundreds of copies of a gene could be transcribed; but that's not how the process naturally happens. In this work, the researchers exposed cells growing in culture to fluorescent antibodies that would illuminate various parts of the transcription mechanism. The cell line contains a reporter gene that lights up when transcribed. They were able to see the transcription enzyme RNA polymerase II (RNAP2) as some of the amino acids making up the enzyme gain phosphate groups (and are phosphorylated). Three steps in the transcription cycle were highlighted by different colors, and the intensity of the fluorescence also changed.

The scientists were able to use this data to model the spatiotemporal movement of RNAP2 throughout a transcription cycle.

"The interdisciplinary science here is a fantastic blending of new experimental capabilities and a new approach for mechanistic computational modeling of single-cell dynamics, both of which are very novel in their respective fields," noted study supervisor Brian Munsky, an associate professor in chemical and biological engineering at CSU.

Image credit: Public domain

The research team was also able to create a model based on their results, and use it to learn more about transcription. For example, they've suggested that for every burst of transcriptional activity, a cluster of five to forty RNA polymerases gather around a gene's promoter. Eventually, about 46 percent of that group succeeds in transcribing a copy of a gene. They also found that each RNA took about five minutes before being transcribed and released, although I assume that figure may be different for different genes depending on their size and other features.

The scientists are hopeful that this technology has other applications, and could be combined with CRISPR to investigate individual genes under manipulation. One day soon, it may be possible to actually see dysfunctional processes, as they occur in disease, while they happen at the level of an individual cell or single gene.

"The ability to resolve the spatial and temporal dynamics of the transcription cycle, in one gene, is the most exciting aspect of this work," Forero said.

Sources: AAAS/Eurekalert! via Colorado State University, Nature Communications

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
APR 18, 2021
Cell & Molecular Biology
Controlling the Epigenome with CRISPRoff & CRISPRon
APR 18, 2021
Controlling the Epigenome with CRISPRoff & CRISPRon
Some parts of the genome are simple; many genes encode for proteins, and if there is an error in one of those protein-co ...
APR 19, 2021
Cell & Molecular Biology
Insight Into the Molecular Basis of Rheumatoid Arthritis
APR 19, 2021
Insight Into the Molecular Basis of Rheumatoid Arthritis
New research has shown how variants in an immune gene can lead to a high risk of developing the autoimmune disorder rheu ...
APR 22, 2021
Genetics & Genomics
A Novel Mechanism of Gene Regulation is Revealed
APR 22, 2021
A Novel Mechanism of Gene Regulation is Revealed
For simplicity's sake, DNA is though of as a double-stranded molecule made of nucleotide bases A, G, C, and T, and RNA a ...
APR 27, 2021
Neuroscience
Leaky Blood-Brain Barrier Linked to Schizophrenia
APR 27, 2021
Leaky Blood-Brain Barrier Linked to Schizophrenia
Researchers from the University of Pennsylvania have found that people with schizophrenia may have a more permeable bloo ...
MAY 06, 2021
Clinical & Molecular DX
Using Biology as Technology: A Paradigm Shift
MAY 06, 2021
Using Biology as Technology: A Paradigm Shift
Digital networks have changed the world by integrating into almost every aspect of our lives, but they have yet to direc ...
MAY 31, 2021
Genetics & Genomics
Gene Expression is Different in Two Parts of the Hippocampus
MAY 31, 2021
Gene Expression is Different in Two Parts of the Hippocampus
The hippocampus is a region of the brain thought to play a role in many different neurological and psychiatric disorders ...
Loading Comments...