Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Kinks, Bends & Repairs: DNA-Bending Protein Studied

31.05.2012
DNA, deoxyribonucleic acid, forms a blueprint of life represented by billions of chemical "base-pairs." But mismatch just one of these complementary pairs, and the genetic code gets altered. While certain proteins can diffuse along DNA strands to search for damaged sites, how they find them -- and how quickly -- remain unanswered questions.

University of Illinois at Chicago physics professor Anjum Ansari hopes to find some answers, supported by a new five-year, $1.14 million National Science Foundation grant.

Ansari and her UIC laboratory team are studying two classes of DNA-bending proteins. One is a "damage recognition" protein that recognizes a mismatched base-pair, binds to that site, and then signals for helper proteins to gather and aid in the repair. The other protein is an enzyme that targets invader DNA, cutting it apart.

Ansari is collaborating with other researchers at UIC, University of Pittsburgh, Wesleyan University and Arizona State University to study different aspects of these proteins.

Ansari's lab is one of only a few equipped to monitor the dynamics of DNA bending in complex with these proteins on timescales ranging from several milliseconds down to as fast hundreds of nanoseconds -- or less than one-millionth of a second.

The instruments in her lab are designed to look at macromolecules as they change their shapes within this time window -- "which is precisely the time window in which proteins recognize their specific binding sites," she said.

Researchers have made measurements at the longer timescales on which proteins diffuse along DNA in search of target sites Ansari said, "but not much is known about the timescale of the recognition process, for virtually any protein."

Her lab's experiments "are designed to make time-resolved measurements of how a protein, when it reaches its target site, transforms the DNA from a conformation in which it is straight to one which is kinked and bent," Ansari said, and to "learn about the recognition mechanism by watching the dynamics -- or time scales -- on which this happens."

Many other biophysical questions about this protein-DNA interaction will be investigated by the team, including the presence of subtle kinks in DNA structure at the damage sites in the absence of a bound protein.

"Clearly, the kinked conformation of the DNA facilitates the [protein's] recognition that something is wrong at the site," Ansari said. "The question we're addressing is, 'Is it the protein that bends and kinks the DNA when it reaches that site?' Or does the DNA, on its own, have a propensity to adopt these locally bent conformations because there's a mismatch -- and the protein, when it is moving along on the DNA, recognizes that something is not right at certain spots?"

DNA gets damaged in various ways -- sometimes during replication, sometimes by ultraviolet radiation, and sometimes through more subtle cellular processes. Damaged DNA can lead to serious diseases, so a better understanding of how proteins make repairs can help when designing new and better therapies.

Ansari will incorporate some aspects of her research in undergraduate physics labs that she plans to develop as part of a new biophysics curriculum at UIC.

Paul Francuch | Newswise Science News
Further information:
http://www.uic.edu

Further reports about: Bends DNA-Bending Kinks Protein Repairs UIC cellular process serious disease

More articles from Life Sciences:

nachricht Individual Receptors Caught at Work
19.10.2017 | Julius-Maximilians-Universität Würzburg

nachricht Rapid environmental change makes species more vulnerable to extinction
19.10.2017 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>