The highest resolution images of a single DNA molecule ever captured were taken by a team of scientists and show atoms ‘dancing’ as they rotate and twist.
Researchers from the universities of Sheffield, Leeds and York have combined advanced atomic microscopy with supercomputer simulations to create videos of the molecules.
The resolution, along with the simulations, allows the team to map and observe the motion and position of each atom within a single strand of DNA.
According to the British team behind the study, if the DNA could be observed so finely, the development of new gene therapies could accelerate.
Researchers from the universities of Sheffield, Leeds and York have combined advanced atomic microscopy with supercomputer simulations to create videos of the molecules.
The imagery shows in unprecedented detail how the stress and strain placed on DNA when it is plugged into cells can change shape.
Previously, scientists could only see DNA using microscopes that were limited to taking static images. The video shows the motion of the atoms.
Images are so detailed that it is possible to see the iconic double helical structure of DNA, but in combination with the simulations, the researchers were able to see the position of each atom in the DNA and how it rotates and twists.
Every human cell contains two meters of DNA and to fit into our cells, it evolved to twist, turn and roll up.
This means that loop-like DNA occurs throughout the genome and forms shaped structures that behave more dynamically than their relaxed counterparts.
The team looked at DNA mini-circles, which are special because the molecule binds on both sides to form a loop.
This loop enabled the researchers to give the DNA mini-circles an extra twist, making the DNA dance more powerfully.
When the researchers relaxed DNA image, without turning, they saw that it did very little.
However, when they give the DNA an extra twist, it suddenly becomes more dynamic and can take many exotic forms.
These exotic dance steps are the key to finding binding mates for the DNA, such as when they take on a wider variety of forms, then a greater variety of other molecules find it attractive.
Images are so detailed that it is possible to see the iconic double helical structure of DNA, but in combination with the simulations, the researchers were able to see the position of each atom in the DNA and how it rotates and twists.
These exotic dance moves are the key to finding binding mates for the DNA, such as when they take on a wider variety of forms, then a greater variety of other molecules find it attractive.
Previous research from Stanford has suggested that DNA mini-circuits are potential indicators of health and aging and could serve as early indicators of disease.
Since the DNA mini-circles can twist and bend, it can also become very compact.
If you can study DNA so closely, it can accelerate the development of new gene therapies by using how twisted and compacted DNA circles can push into cells.
Dr Alice Pyne, lecturer in Polymers & Soft Matter at the University of Sheffield, who captured the footage, said: ‘To see is believable, but with something as small as DNA, it was very challenging to understand the helical structure of the whole DNA molecule.
“The videos we have developed enable us to observe DNA distortion in a level of detail that has never been seen before.”
Previous Stanford research has suggested that DNA mini-circuits are potential indicators of health and aging and could serve as early indicators of disease
Being able to study DNA in such detail can accelerate the development of new gene therapies by using how twisted and compacted DNA circles can push them into cells.
Professor Lynn Zechiedrich of the Baylor College of Medicine in Houston, Texas, USA, who made the DNA minicircles used in the study, was important.
“They show with remarkable detail how wrinkled, bubbled, cracked, denatured and strangely shaped that we hope to one day be able to control.”
Dr Sarah Harris of the University of Leeds, who oversaw the research, said the work showed that the laws of physics apply just as much to small loop-like DNA as to sub-atomic particles and entire galaxies.
‘We can use supercomputers to understand the physics of twisted DNA. This should help researchers design customized mini-circles for future therapies. ‘
The study, a combination of high-resolution atomic force microscopy with molecular dynamics simulations, shows that DNA supercoiling causes kinks and defects that increase flexibility and recognition are published in Nature Communications.