Navigation Links
Researchers find new way to study how enzymes repair DNA damage
Date:1/28/2010

COLUMBUS, Ohio -- Researchers at Ohio State University have found a new way to study how enzymes move as they repair DNA sun damage -- and that discovery could one day lead to new therapies for healing sunburned skin.

Ultraviolet (UV) light damages skin by causing chemical bonds to form in the wrong places along the DNA molecules in our cells. Normally, other, even smaller molecules called photolyases heal the damage. Sunburn happens when the DNA is too damaged to repair, and cells die.

Photolyases have always been hard to study, in part because they work in tiny fractions of a second. In this week's online edition of the Proceedings of the National Academy of Sciences, Ohio State physicist and chemist Dongping Zhong and his colleagues describe how they used ultra-fast pulses of laser light to spy on a photolyase while it was healing a strand of DNA.

This is the first time that anyone has observed this enzyme motion without first attaching a fluorescent molecule to the photolyase, which disturbs its movements. They were able to see the enzyme's motion to help the healing process as it happens in nature.

"Now that we have accurately mapped the motions of a photolyase at the site of DNA repair, we can much better understand DNA repair at the atomic scale, and we can reveal the entire repair process with unprecedented detail," said Zhong, the Robert Smith Associate Professor of Physics, and associate professor in the departments of chemistry and biochemistry at Ohio State.

Such small motions are very hard to study. Typically, researchers deal with the problem by attaching tiny bits of fluorescent molecules to the enzymes they are trying to study. But adding an extra molecule to an enzyme such as photolyase could change how it moves.

"Once you tag it, you can't be sure that the motions you detect are the true motions of the molecule as it would normally function," Zhong explained.

So instead of using tags, he and his team took laser "snapshots" of a single photolyase in action in the laboratory. They mapped the shape and position of the photolyase molecule as it broke up the harmful chemical bonds in DNA caused by UV light. The whole reaction lasted only a few billionths of a second.

In nature, DNA avoids damage by converting UV rays into heat. Sunscreen lotions protect us by reflecting sunlight away from the skin, and also by dissipating UV as heat.

Sunburn happens when the DNA absorbs the UV energy instead of converting it to heat. This is due in part to the random position of the DNA molecule within our cells when the UV hits it. When the UV energy is absorbed, it triggers chemical reactions that form lesions -- errant chemical bonds -- along the DNA strand.

If photolyases are unable to completely repair the lesions, the DNA can't replicate properly. Badly damaged cells simply die that's what gives sunburn its sting. Scientists also believe that chronic sun damage creates mutations that lead to diseases such as skin cancer.

The work in Zhong's lab is fundamental to the understanding of how those molecules interact. Other researchers could use this information to design drugs to heal sun damage.

"Of course, the ultimate goal of studying DNA repair is to help design artificial systems to mimic it," he said.


'/>"/>

Contact: Dongping Zhong
Zhong.28@osu.edu
614-292-3044
Ohio State University
Source:Eurekalert

Related medicine news :

1. UCLA researchers image earliest signs of Alzheimers, before symptoms appear
2. Researchers find leukemia cells metabolize fat to avoid cell death
3. Hair Cloning Not Yet Recommended by Researchers Who Developed the Technique
4. Researchers develop new tool for gene delivery
5. Researchers at Meharry Medical College Find Green Tea Extract Showing Promise for Treatment of Uterine Fibroids
6. Researchers welcome new multiple sclerosis drug
7. Barrow researchers receive more than $2 million in NIH grants for nicotine studies
8. Researchers discover method to objectively identify PTSD
9. Researchers find a treatment for deadly brain tumor
10. Researchers find new insights into inherited retinal disease
11. Pitt researchers raise concern over frequency of surveillance colonoscopy
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2017)... ... 2017 , ... Ushio America proudly introduces the new ... solution for F32T8 fluorescent lamps on most instant-start and programmed-start electronic ballasts so ... lamps utilize the existing electronic ballast, saving labor and maintenance costs. It’s easy ...
(Date:4/28/2017)... Md. (PRWEB) , ... April 28, 2017 , ... ... Association of America (UCAOA) and College of Urgent Care Medicine will host industry ... workshops, sessions and speakers will help those in the industry adapt to the ...
(Date:4/28/2017)... ... April 28, 2017 , ... Researchers at ... ActiGraph’s CentrePoint Data Hub in a sample of participants enrolled in ... activity and sleep monitoring solutions for the global scientific community. The company’s new ...
(Date:4/28/2017)... ... 28, 2017 , ... Rob Lowe is a popular actor that has been ... to an educational purpose as the host of the “Informed” series. The program focuses ... recent episode, the series focuses on thyroid cancer. , Although thyroid cancer is an ...
(Date:4/27/2017)... ... April 27, 2017 , ... Healthcare companies are trying ... will rapidly reject an outdated healthcare executive resume. , “If you’re a healthcare executive ... executive resume and wondering if it’s as ready as you are for a new ...
Breaking Medicine News(10 mins):
(Date:4/20/2017)... WOONSOCKET, R.I. , April 20, 2017 /PRNewswire/ ... (NYSE: CVS), today unveiled a new store design ... new assortment of healthier food, health-focused products and ... the store to help customers discover new offerings. ... represent the next evolution of the customer experience ...
(Date:4/20/2017)... April 20, 2017 NeuroVive Pharmaceutical AB ... announced positive preclinical results demonstrating anti-fibrotic effects ... non-alcoholic steatohepatitis (NASH), in an additional well-validated ... NV556 has previously shown similar anti-fibrotic effects ... NeuroVive,s scientists present novel data demonstrating anti-fibrotic ...
(Date:4/19/2017)... , April 19, 2017  IRIDEX Corporation (Nasdaq: ... financial results for the first quarter 2017 after the ... Company,s management team will host a corresponding conference call ... Investors interested in listening to the conference ... domestic callers or (703) 326-3030 for international callers, using ...
Breaking Medicine Technology: