Featured Research

from universities, journals, and other organizations

Chemical Probe Reveals Ultrafast Movements Of DNA Proteins

Date:
February 2, 2000
Source:
Ohio State University
Summary:
A probe designed by chemists at Ohio State University has revealed a new secret in the life of DNA: The strands of compounds making up the molecule vibrate, stretch, and swing to and fro in tiny movements that last only a fraction of a second. While scientists suspected that DNA could move this way, the technology didn't exist to confirm their suspicions until now.

COLUMBUS, Ohio -- A probe designed by chemists at Ohio State University has revealed a new secret in the life of DNA: The strands of compounds making up the molecule vibrate, stretch, and swing to and fro in tiny movements that last only a fraction of a second.

Related Articles


While scientists suspected that DNA could move this way, the technology didn't exist to confirm their suspicions until now.

"This research may allow us to answer fundamental questions about how DNA works," said Robert Coleman, associate professor of chemistry at Ohio State.

The probe may improve drug design and help doctors understand diseases that arise from genetic mutations, such as cancer.

Coleman and Mihaela Madaras, a former postdoctoral researcher in chemistry, constructed the fluorescent probe and a strand of synthetic DNA. The probe resembles a set of base pairs on the DNA strand, and replaces the base pairs during theexperiment.

The Ohio State chemists conducted this work as a team with scientists at the University of South Carolina. Those scientists -- Catherine Murphy and Mark Berg, both associate professors of chemistry and biochemistry, and Eric Brauns, a graduate student -- shined an ultrafast burst of light onto the probe to detect movements in the DNA that lasted only trillionths of a second.

The results appear this month in the Journal of the American Chemical Society.

"DNA is not rigid, it's flexible. It vibrates. It 'breathes' so to speak," explained Coleman. "Its components undergo movements on a time scale that occurs much faster than any measurements that have been made before."

Previously, scientists could only measure the less delicate movements of the whole twisted ladder of molecules that makes up a DNA helix. For instance, they could examine what happens when an strand of DNA coils and folds in upon itself like a crumpled rubber band. Ohio State's probe allowed the South Carolina scientists to measure much smaller movements -- those of the chemical base pairs that make up the rungs of the ladder.

According to Coleman, as these base pairs move, they change the shape of the DNA molecule, and that may explain why certain proteins and drugs recognize certain sequences of DNA.

"This is the really exciting part," said Coleman. "The applications of the probe are tremendous."

In particular, Coleman is interested in anti-tumor agents that damage DNA, and the enzymes in the body that repair damage. "Maybe enzymes are able to recognize damaged areas because the shape of the DNA has changed. We could put our probe into a piece of DNA near a damaged site, and we could see how the function of the DNA changed as a result of being damaged," he said.

The probe could help scientists understand diseases that result when damaged DNA causes cells to confuse their chemical instructions and malfunction. Doctors believe diseases such as hypertension, cancer, heart disease, diabetes, and even conditions such as schizophrenia stem from mutations in DNA that go unrepaired.

"To understand what's happening in these situations, you have to get inside the DNA. That's where the probe comes in," said Coleman. "Our probe is different because it exactly replaces one of the natural base pairs on the DNA backbone. To the best of our ability to detect any changes, our probe didn't alter the overall structure or distort the DNA."

Other scientists have had to attach probes to the outside of the DNA helix so the measurements they've gotten are not as precise, he said.

Coleman and Madaras designed the probe on computer, then created it in the laboratory, along with a synthetic strand of DNA for the test.

During the experiments, the intensity of light reflected from the probe rose and fell over the course of 300 picoseconds, or 300 trillionths of a second, indicating that the components of the DNA strand were moving energetically during that time.

This technique mirrors that of Ahmed Zewail, 1999 Nobel Prizewinner in chemistry, who uses ultrafast pulses of light to view the movement of atoms inside molecules.

This work was primarily funded by the National Institutes of Health and the National Science Foundation.


Story Source:

The above story is based on materials provided by Ohio State University. Note: Materials may be edited for content and length.


Cite This Page:

Ohio State University. "Chemical Probe Reveals Ultrafast Movements Of DNA Proteins." ScienceDaily. ScienceDaily, 2 February 2000. <www.sciencedaily.com/releases/2000/02/000202075929.htm>.
Ohio State University. (2000, February 2). Chemical Probe Reveals Ultrafast Movements Of DNA Proteins. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2000/02/000202075929.htm
Ohio State University. "Chemical Probe Reveals Ultrafast Movements Of DNA Proteins." ScienceDaily. www.sciencedaily.com/releases/2000/02/000202075929.htm (accessed October 23, 2014).

Share This



More Health & Medicine News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Fears Keep Guinea Hospitals Empty

Ebola Fears Keep Guinea Hospitals Empty

AP (Oct. 23, 2014) Fears of Ebola are keeping doctors and patients alike away from hospitals in the West African nation of Guinea. (Oct. 23) Video provided by AP
Powered by NewsLook.com
Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Orthodontist Mom Jennifer Salzer on the Best Time for Braces

Working Mother (Oct. 22, 2014) Is your child ready? Video provided by Working Mother
Powered by NewsLook.com
U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

U.S. Issues Ebola Travel Restrictions, Are Visa Bans Next?

Newsy (Oct. 22, 2014) Now that the U.S. is restricting travel from West Africa, some are dropping questions about a travel ban and instead asking about visa bans. Video provided by Newsy
Powered by NewsLook.com
More People Diagnosed With TB In 2013, But There's Good News

More People Diagnosed With TB In 2013, But There's Good News

Newsy (Oct. 22, 2014) The World Health Organizations says TB numbers rose in 2013, but it's partly due to better detection and more survivors. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins