Featured Research

from universities, journals, and other organizations

DNA's double stranded stretch: Models simulate what happens to DNA strands when stretched to the breaking point

Date:
October 25, 2012
Source:
Springer
Summary:
Theoretical physicists like to play with very unconventional toys. Researchers have adopted a seemingly playful approach to examining what happens to a double stranded molecule of DNA when it is stretched to the breaking point, in a new study.

Theoretical physicists like to play with very unconventional toys. Manoel Manghi from Toulouse University in France and his colleagues have adopted a seemingly playful approach to examining what happens to a double stranded molecule of DNA when it is stretched to the breaking point, in a study about to be published in EPJ E.

Related Articles


Instead of using optical tweezers to stretch DNA as previously done in experimental settings, the authors focused on using a theoretical model to account for the structural deformations of DNA and determine how its mechanical characteristics could explain certain biological processes.

Over fifteen years ago, scientists discovered that DNA undergoes two structural transitions when pulled from both ends. The problem is that in experimental conditions these two transitions can overlap and can therefore be difficult to observe. Instead, Manghi and colleagues relied on a standard mathematical tool referred to as a 'coupled discrete wormlike chain-Ising model' to simulate DNA stretching and match experimental observations.

Thanks to their theoretical approach, the authors confirmed that after overcoming initial resistance to stretching, at a force of around 65 piconewtons (pN) in strength, the DNA stretches to almost twice its original length while also becoming less rigid. They also confirmed the other known structural transition occurring at around 135 pN. Although the critical forces of both transitions depend on the DNA sequence, they found it is the second one that most depends on it.

Beyond 135pN, DNA strands start peeling apart into single stranded DNAs that are similar to those obtained when DNA is heated up and undergoes thermal denaturation. This model thus bridges the gap between force-induced mechanical stretching and thermal denaturation and could potentially help understand how DNA performs its biological functions such as interaction with proteins and how it is packaged, say, in viruses.


Story Source:

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


Journal Reference:

  1. Manoel Manghi, Nicolas Destainville, John Palmeri. Mesoscopic models for DNA stretching under force: New results and comparison with experiments. The European Physical Journal E, 2012; 35 (10) DOI: 10.1140/epje/i2012-12110-2

Cite This Page:

Springer. "DNA's double stranded stretch: Models simulate what happens to DNA strands when stretched to the breaking point." ScienceDaily. ScienceDaily, 25 October 2012. <www.sciencedaily.com/releases/2012/10/121025110156.htm>.
Springer. (2012, October 25). DNA's double stranded stretch: Models simulate what happens to DNA strands when stretched to the breaking point. ScienceDaily. Retrieved January 26, 2015 from www.sciencedaily.com/releases/2012/10/121025110156.htm
Springer. "DNA's double stranded stretch: Models simulate what happens to DNA strands when stretched to the breaking point." ScienceDaily. www.sciencedaily.com/releases/2012/10/121025110156.htm (accessed January 26, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, January 26, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Florida Might Legalize Black Bear Hunting

Florida Might Legalize Black Bear Hunting

Newsy (Jan. 24, 2015) A string of black bear attacks has Florida officials considering lifting the ban on hunting the animals to control their population. Video provided by Newsy
Powered by NewsLook.com
Ebola Killing Large Portion Of Ape Population

Ebola Killing Large Portion Of Ape Population

Newsy (Jan. 23, 2015) Experts estimate Ebola has wiped out one-third of the world&apos;s gorillas and chimpanzees. Video provided by Newsy
Powered by NewsLook.com
Controversy Shrouds Captive Killer Whale in Miami

Controversy Shrouds Captive Killer Whale in Miami

Reuters - Light News Video Online (Jan. 23, 2015) Activists hope the National Oceanic and Atmospheric Agency (NOAA) will label killer whales endangered, allowing lawyers to sue a Miami aquarium to release an orca into the wild after 44 years. Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
‘Healthy’ Foods That Surprisingly Pack on Pounds

‘Healthy’ Foods That Surprisingly Pack on Pounds

Buzz60 (Jan. 23, 2015) Some &apos;healthy&apos; foods are actually fattening. Fitness and nutrition expert John Basedow (@JohnBasedow) shines a light on the sneaky foods like nuts, seeds, granola, trail mix, avocados, guacamole, olive oil, peanut butter, fruit juices and salads that are good for you...but not so much for your waistline. Video provided by Buzz60
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


Plants & Animals

Earth & Climate

Fossils & Ruins

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