Study: DNA stretched winds more tightly

July 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: 'Sleeping dogs' threaten the genome as we age

Related Stories

'Sleeping dogs' threaten the genome as we age

December 5, 2014

The genomes of many organisms, humans included, are littered with repetitive sequences of DNA called retrotransposons. In a new "Perspective" in the journal Science, four biologists write that while most retrotransposons ...

Hydrothermal vents could explain chemical precursors to life

June 16, 2014

Roy Price first heard about the hydrothermal vents in New Caledonia's Bay of Prony a decade ago. Being a scuba diver and a geologist, he was fascinated by the pictures of a 38-meter-high calcite "chimney" that had precipitated ...

Aging cells lose their grip on DNA rogues

January 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 researchers ...

Monk parakeets: Immigrants to New York via Argentina

October 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

February 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

Volcanic bacteria take minimalist approach to survival

August 4, 2015

New research by scientists at the University of Otago and GNS Science is helping to solve the puzzle of how bacteria are able to live in nutrient-starved environments. It is well-established that the majority of bacteria ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.