JUL 23, 2021 5:13 PM PDT

DNA Structure Affects Transcription & the Reverse May Also be True

WRITTEN BY: Carmen Leitch

As imaging tools continue to get more sophisticated, researchers have been able to actually watch biological processes as they are happening in live cells. Scientists have now visualized loops of DNA molecules and seen the three-dimensional structure of these loops. Active genes have to be copied from the DNA molecule into mRNA molecules that the cell can use to generate proteins. This research has helped the investigators learn more about how the transcription of RNA affects DNA. The study, which has been reported in Molecular Cell, has suggested that RNA transcription has an influence on the architecture of the genome, and that the process creates forces that ripple through DNA.

DNA seen with the team's microscopy tools / Credit: Vicky Neguembor / CRG

When genes are transcribed, the double strand of the DNA molecule has to be 'unzipped,' which alters its three-dimensional form and overtwists or supercoils downstream portions of the molecule. This new research has shown that when DNA is supercoiled, structural proteins known as cohesins can surf across DNA strands, which alters the structure and changes the genome's shape. In this work, the scientists used high-powered miscoscopy to visualize chromatin loops and cohesins holding the structure together inside of cells.

DNA has to be carefully organized and packaged so it will fit into the nucleus of cells; compacted DNA that's been organized with other proteins is known as chromatin. The structure of the genome can influence gene expression because active genes have to be physically accessible to the cell's transcription machinery. Chromatin contains loops that can connect parts of the genome that may be very far apart in the DNA's linear sequence. Transcription also seems to be bringing certain parts of genome together.

Some genetic disorders are associated with mutations in genes that code for cohesin or proteins that regulate it, as well as errors in chromatin folding. This study may help scientists learn more about these diseases.

"What we have found is important because it shows the biological process of transcription plays an additional role beyond its fundamental task of creating RNA that eventually turn into proteins. Transcription indirectly compacts the genome in an efficient manner and helps different regions of the genome talk to each other," said first study author Vicky Neguembor, a Staff Scientist at the Centre for Genomic Regulation.

Sources: AAAS/Eurekalert! via Center for Genomic Regulation, Molecular Cell

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
JUN 26, 2021
Space & Astronomy
Cardiac Atrophy Findings May Aid Astronauts in Long Space Flights
JUN 26, 2021
Cardiac Atrophy Findings May Aid Astronauts in Long Space Flights
Researchers led by Cincinnati Children’s Hospital Medical Center have discovered the molecular process behind a da ...
JUL 04, 2021
Genetics & Genomics
New Insights Into the Mechanisms of Rett Syndrome
JUL 04, 2021
New Insights Into the Mechanisms of Rett Syndrome
Rett syndrome is a neurological disorder that mostly affects girls; affected individuals develop normally until they're ...
AUG 03, 2021
Genetics & Genomics
Aging Cells May Lose Control of Where an mRNA Sequence Starts
AUG 03, 2021
Aging Cells May Lose Control of Where an mRNA Sequence Starts
When a gene is active, it's transcribed from DNA to RNA, and a specific sequence in the genetic code acts like a sig ...
AUG 22, 2021
Genetics & Genomics
A Natural Protein to 'SEND' Gene Editing Cargo to Cells
AUG 22, 2021
A Natural Protein to 'SEND' Gene Editing Cargo to Cells
One of the most difficult aspects of gene therapy might be ensuring that it gets into the right cells safely so it can h ...
SEP 06, 2021
Cell & Molecular Biology
Researchers Miniaturize the CRISPR Gene Editing Tool
SEP 06, 2021
Researchers Miniaturize the CRISPR Gene Editing Tool
The CRISPR gene editor uses RNA molecules that act as guides that ta Cas9 proteins, which are like enzymatic scissors, t ...
SEP 19, 2021
Genetics & Genomics
A New Understanding of Japanese History Through Genetics
SEP 19, 2021
A New Understanding of Japanese History Through Genetics
Palaeoarchaeologists, human geographers, and other scientists have sought to understand the evolution of humans, their c ...
Loading Comments...