JUL 24, 2019 4:10 PM PDT

New study finds that the structure of chromosomes may not be as important to transcriptional activity as we once thought

WRITTEN BY: Carly Boyd

Among scientists, it is widely accepted that the structure of genomes largely controls their transcriptional activity within the cell. Structural features known as chromatin are responsible for this regulation of activity. Chromatin is a tightly wound section of DNA and protein within the nucleus of the cell. How tightly (heterochromatin) or loosely (euchromatin) DNA is wound directly affects the transcriptional activity of that section of DNA. Or does it?

Ghavi-Helm et al. of the Furlong Lab at the European Molecular Biology Laboratory in Heidelburg, Germany recently published findings in Nature Genetics that contradict this widely accepted theory. The team used balancer chromosomes in Drosophila melanogaster (or fruit flies) to look more closely at the relationship between chromatin structures and gene expression. Balancer chromosomes are used to create a population of flies with a mutation in one set of chromosomes that will be maintained throughout several fly generations and will not become lethal to the fly. In this study, the second and third chromosomes were mutated with many inversions, duplications, and deletions. These balancers and the wild-type chromosomes were used to "systematically map allele-specific chromatin topology" and compare it to the corresponding region of the chromosome.

"Fig. 1: Using balancer chromosomes to probe the relationship between genome architecture and function." This figure shows how the balancer chromosomes were used to change the structure of the chromosome from the wild-type or normal chromosome.

Interestingly, only a subset of genes expression was altered when the chromosome was rearranged, and the topology was effected. According to Ghavi-Helm et al., "these results suggest that many genes are generally impervious to the large-scale topological features of their surroundings." However, some genes were effected in instances where there were far more topological changes, supporting the original theory. Together this study reveals that the structure of the genome is not enough to determine gene transcriptional activity.

Article sources: A genome disconnect, Yad Ghavi-Helm et al.

 

To learn more about chromatin and its role in gene regulation, watch this video:

 

About the Author
  • Being a master's student in Cell and Molecular Biology, I'm interested in a variety of topics in biology. Currently, I'm researching ways to identify putative enhancer elements for peripheral nervous system development in the genome of Ciona intestinalis (our closest invertebrate relative).
You May Also Like
OCT 01, 2020
Cancer
Understanding in vivo Metabolomics: C13 Isotope Studies
OCT 01, 2020
Understanding in vivo Metabolomics: C13 Isotope Studies
One key to understanding cancer metabolomics lies in the ability to accurately replicate the natural environment of the ...
OCT 04, 2020
Genetics & Genomics
The Intriguing Genome of Mitochondria
OCT 04, 2020
The Intriguing Genome of Mitochondria
Our cells carry special structures called organelles, with each different organelle performing various specialized, crit ...
OCT 09, 2020
Genetics & Genomics
Using CRISPR to Destroy Cancer Cells
OCT 09, 2020
Using CRISPR to Destroy Cancer Cells
Researchers have developed a way to selectively target certain cancer cells with CRISPR.
NOV 11, 2020
Health & Medicine
A smart path for novel biologics
NOV 11, 2020
A smart path for novel biologics
Introduction  Cell culture is at the heart of the production process for many biopharmaceuticals, but finding the o ...
OCT 18, 2020
Genetics & Genomics
'Silent' Mutations Might Have Given SARS-CoV-2 an Edge
OCT 18, 2020
'Silent' Mutations Might Have Given SARS-CoV-2 an Edge
The pandemic virus SARS-CoV-2 is thought to have originated in bats, like many viruses. To make the leap and infect anot ...
OCT 28, 2020
Cell & Molecular Biology
Mimicking Cells With a Microfluidic Chip
OCT 28, 2020
Mimicking Cells With a Microfluidic Chip
Cell culture models are one way for scientists to learn more about biology. But cells grow in large cultures that are of ...
Loading Comments...