Featured Research

from universities, journals, and other organizations

Elasticity Of Short DNA Molecules: In Theory And Experiment

Date:
December 10, 2007
Source:
Biophysical Society
Summary:
DNA, the biomolecule that provides the blueprint for life, has a lesser-known identity as a stretchy polymer. The authors have found a flaw in the most common model for DNA elasticity, a discovery that will improve the accuracy of single-molecule research and perhaps pave the way for DNA to become an official standard for measuring picoscale forces, a notoriously difficult challenge.

DNA, the biomolecule that provides the blueprint for life, has a lesser-known identity as a stretchy polymer. The authors have found a flaw in the most common model for DNA elasticity, a discovery that will improve the accuracy of single-molecule research and perhaps pave the way for DNA to become an official standard for measuring picoscale forces, a notoriously difficult challenge.

Related Articles


The experiments described in this paper* reveal that a classic model for measuring the elasticity of double-stranded DNA leads to errors when the molecules are short. For instance, measurements are off by up to 18 percent for molecules 632 nanometers long, and by 10 percent for molecules about twice that length. (By contrast, the DNA in a single human cell, if linked together and stretched out, would be about 2 meters long.)

The old elasticity model assumes that polymers are infinitely long, whereas the most popular length for high precision single-molecule studies is 600 nm to 2 microns, coauthor Tom Perkins says. Accordingly, several university collaborators developed a new theory, the finite worm-like chain (FWLC) model, which improves accuracy by incorporating three previously neglected effects, including length.

The work described in this article is part of a NIST project studying the possible use of DNA as a picoforce standard, because enzymes build DNA with atomic precision. DNA already is used informally to calibrate atomic force microscopes. An official standard could, for the first time, enable picoscale measurements that are traceable to internationally accepted units. DNA elasticity could provide a force standard from 0.1 -10 pico-Newtons (pN), where 1 pN is the approximate weight of an E. coli cell or the force exerted by 1 milliwatt of light reflected off a mirror.

*This research is published in the December 15, 2007 issue of Biophysical Journal (Volume 93, Issue 12).

The work was supported by the Alfred P. Sloan Foundation, a Burroughs Wellcome Fund Career Award in the Biomedical Sciences, the Butcher Foundation, a W.M. Keck Grant in the RNA Sciences, NIST, and the National Science Foundation.


Story Source:

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


Cite This Page:

Biophysical Society. "Elasticity Of Short DNA Molecules: In Theory And Experiment." ScienceDaily. ScienceDaily, 10 December 2007. <www.sciencedaily.com/releases/2007/12/071207150738.htm>.
Biophysical Society. (2007, December 10). Elasticity Of Short DNA Molecules: In Theory And Experiment. ScienceDaily. Retrieved November 27, 2014 from www.sciencedaily.com/releases/2007/12/071207150738.htm
Biophysical Society. "Elasticity Of Short DNA Molecules: In Theory And Experiment." ScienceDaily. www.sciencedaily.com/releases/2007/12/071207150738.htm (accessed November 27, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Thursday, November 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Classic Hollywood Memorabilia Goes Under the Hammer

Classic Hollywood Memorabilia Goes Under the Hammer

Reuters - Entertainment Video Online (Nov. 26, 2014) — The iconic piano from "Casablanca" and the Cowardly Lion suit from "The Wizard of Oz" fetch millions at auction. Sara Hemrajani reports. Video provided by Reuters
Powered by NewsLook.com
Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) — Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) — The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Feast Your Eyes: Lamb Chop Sent Into Space from UK

Feast Your Eyes: Lamb Chop Sent Into Space from UK

Reuters - Light News Video Online (Nov. 25, 2014) — Take a stab at this -- stunt video shows a lamb chop's journey from an east London restaurant over 30 kilometers into space. Rough Cut (no reporter narration). Video provided by Reuters
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