Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Designer molecule shines a spotlight on mysterious 4-stranded DNA

09.09.2015

A small fluorescent molecule has shed new light on knots of DNA thought to play a role in regulating how genes are switched on and off.

DNA is typically arranged in a double helix, where two strands are intertwined like a coiled ladder, but previous research has shown the existence of unusual DNA structures called quadruplexes, where four strands are arranged in the form of little knots.


Structure of a G-quadruplex DNA highlighting one of the guanine tetrads.

Credit: Imperial College London

Now researchers at Imperial College London led by Dr Marina Kuimova and Professor Ramon Vilar are unravelling the mysteries of these four-stranded DNA structures. They have created a fluorescent molecule that can reveal the presence of these structures in living cells.

The team used the glowing molecule to target quadruplex DNA inside human bone cancer cells grown in the laboratory. Together with colleagues from Kings College London, they studied the interactions between the two in real time, using powerful microscopes.

Quadruplexes can form when a strand of DNA rich in guanines - one of the four building blocks in DNA - folds over onto itself. Several distinct quadruplex structures have been found in the human genome but their exact role remains unclear. Recent studies have shown they are particularly prevalent in regions nearby oncogenes - genes that have the potential to cause cancer.

"There is mounting evidence that quadruplexes are involved in switching genes on and off because of where they are usually positioned within the genome," says Professor Vilar, from Imperial's Department of Chemistry.

"If this can be proved, it would make quadruplexes an extremely important target for treating diseases such as cancer. But to understand what role they play, we need to be able to study them in living cells. Our new fluorescent molecule allows us to do this by directly monitoring the behaviour of quadruplexes inside living cells in real time."

The team designed the fluorescent molecule to glow more intensely when attached to DNA. Using powerful microscopes they discovered that they could distinguish between the molecules binding to the more common double helical DNA and quadruplex DNA because it glowed for much longer when bound to quadruplexes.

The researchers were also able to visualise the fluorescent molecule being displaced from quadruplex DNA by another molecule known to be a very good quadruplex binder. This suggests that the Imperial molecule could be used to hunt for new compounds that can bind to quadruplexes.

Co-author Arun Shivalingam, who worked on the study during his PhD at Imperial, says: "Until now, to image quadruplexes in cells researchers have had to hold the cells in place using chemical fixation. However, this kills them and brings into question whether the molecule really interacts with quadruplexes in a dynamic environment."

Professor Vilar adds: "We've shown that our molecule could be potentially used to verify in live cells and in real time whether potential quadruplex DNA binders are hitting their target. This could be a game changer to accelerate research into these DNA structures."

The study is published in Nature Communications.

Media Contact

Hayley Dunning
h.dunning@imperial.ac.uk
44-020-759-42412

 @imperialspark

http://www.imperial.ac.uk/press 

Hayley Dunning | EurekAlert!

More articles from Life Sciences:

nachricht Nonstop Tranport of Cargo in Nanomachines
20.11.2018 | Max-Planck-Institut für molekulare Zellbiologie und Genetik

nachricht Researchers find social cultures in chimpanzees
20.11.2018 | Universität Leipzig

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nonstop Tranport of Cargo in Nanomachines

Max Planck researchers revel the nano-structure of molecular trains and the reason for smooth transport in cellular antennas.

Moving around, sensing the extracellular environment, and signaling to other cells are important for a cell to function properly. Responsible for those tasks...

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

Nonstop Tranport of Cargo in Nanomachines

20.11.2018 | Life Sciences

Researchers find social cultures in chimpanzees

20.11.2018 | Life Sciences

When AI and optoelectronics meet: Researchers take control of light properties

20.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>