Study: DNA stretched winds more tightly

Jul 12, 2006

U.S. biochemists say they've found if the DNA molecule's helical structure is stretched, it actually winds itself more tightly.

Although the proposal sounds counterintuitive, Carlos Bustamante and colleagues at the University of California-Berkeley say the DNA double helix winds more tightly when gently stretched. Only if it is tugged at hard does its spiral begin to unfurl.

That, the researcher said, is in contrast to nearly all other helical structures -- such as an old-fashioned candy wrapper, for instance, which unwinds when you pull on its ends.

The scientists made their discovery by studying single DNA molecules with tiny stretching forces applied to them. The discovery may also explain real-life examples of cellular DNA structures that seem to be both taut and yet tightly wound.

The study, now available online, is to appear in a future issue of the journal Nature.

Copyright 2006 by United Press International

Explore further: Vitamin K antagonist plus clopidogrel feasible for PCI

add to favorites email to friend print save as pdf

Related Stories

Aging cells lose their grip on DNA rogues

Jan 30, 2013

(Phys.org)—Transposable elements are mobile strands of DNA that insert themselves into chromosomes with mostly harmful consequences. Cells try to keep them locked down, but in a new study, Brown University ...

Monk parakeets: Immigrants to New York via Argentina

Oct 17, 2012

They appear as invaders, taking over a neighborhood and erecting tall dwellings seemingly overnight. Offspring and relatives soon follow, and their ensuing racket is not to be spoken of in polite company.

A new way to visualize Earth

Feb 17, 2012

As the state geologist for Arizona, Lee Allison knows granite from sandstone, a syncline from an anticline. But he has lacked the ability to look through rocks to visualize the inner workings of the Earth.

Recommended for you

Vitamin K antagonist plus clopidogrel feasible for PCI

9 hours ago

(HealthDay)—Vitamin K antagonists (VKA) combined with clopidogrel may be a better alternative to triple anticoagulant therapy in patients on long-term VKA undergoing percutaneous coronary intervention (PCI) ...

Electronic health records tied to shorter time in ER

9 hours ago

(HealthDay)—Length of emergency room stay for trauma patients is shorter with the use of electronic health records, according to a study published in the September issue of the Journal of Emergency Nursing.

Presence of peers ups health workers' hand hygiene

10 hours ago

(HealthDay)—The presence of other health care workers improves hand hygiene adherence, according to a study published in the October issue of Infection Control and Hospital Epidemiology.

User comments : 0