Featured Research

from universities, journals, and other organizations

Unselfish molecules may have helped give birth to the genetic material of life

Date:
March 8, 2010
Source:
Georgia Institute of Technology
Summary:
One of the biggest questions facing scientists today is how life began. Scientists have discovered that small molecules could have acted as "molecular midwives" in helping the building blocks of life's genetic material form long chains and may have assisted in selecting the base pairs of the DNA double helix.

New research suggests that small molecules could have acted as "molecular midwives" in helping the building blocks of life's genetic material form long chains and may have assisted in selecting the base pairs of the DNA double helix.
Credit: iStockphoto

One of the biggest questions facing scientists today is how life began. How did non-living molecules come together in that primordial ooze to form the polymers of life? Scientists at the Georgia Institute of Technology have discovered that small molecules could have acted as "molecular midwives" in helping the building blocks of life's genetic material form long chains and may have assisted in selecting the base pairs of the DNA double helix.

The research appears in the online early edition of the Proceedings of the National Academy of Sciences beginning March 8, 2010.

"Our hypothesis is that before there were protein enzymes to make DNA and RNA, there were small molecules present on the pre-biotic Earth that helped make these polymers by promoting molecular self-assembly," said Nicholas V. Hud, professor in the School of Chemistry and Biochemistry at the Georgia Institute of Technology. "We've found that the molecule ethidium can assist short oligonucleotides in forming long polymers and can also select the structure of the base pairs that hold together two strands of DNA."

One of the biggest problems in getting a polymer to form is that, as it grows, its two ends often react with each other instead of forming longer chains. The problem is known as strand cyclization, but Hud and his team discovered that using a molecule that binds between neighboring base pairs of DNA, known as an intercalator, can bring short pieces of DNA and RNA together in a manner that helps them create much longer molecules.

"If you have the intercalator present, you can get polymers. With no intercalator, it doesn't work, it's that simple," said Hud.

Hud and his team also tested how much influence a midwife molecule might have had on creating DNA's Watson-Crick base pairs (A pairs with T, and G pairs with C). They found that the midwife used could determine the base pairing structure of the polymers that formed. Ethidium was most helpful for forming polymers with Watson-Crick base pairs. Another molecule that they call aza3 made polymers in which each A base is paired with another A.

"In our experiment, we found that the midwife molecules present had a direct effect on the kind of base pairs that formed. We're not saying that ethidium was the original midwife, but we've shown that the principle of a small molecule working as a midwife is sound. In our lab, we're now searching for the identity of a molecule that could have helped make the first genetic polymers, a sort of 'unselfish' molecule that was not part of the first genetic polymers, but was critical to their formation," said Hud.

The work was supported by the National Aeronautics and Space Administration and the National Science Foundation.


Story Source:

The above story is based on materials provided by Georgia Institute of Technology. The original article was written by David Terraso. Note: Materials may be edited for content and length.


Journal Reference:

  1. Eric D. Horowitz, Aaron E. Engelhart, Michael C. Chen, Kaycee A. Quarles, Michael W. Smith, David G. Lynn, and Nicholas V. Hud. IIntercalation as a means to suppress cyclization and promote polymerization of base-pairing oligonucleotides in a prebiotic world. PNAS, March 8, 2010 DOI: 10.1073/pnas.0914172107

Cite This Page:

Georgia Institute of Technology. "Unselfish molecules may have helped give birth to the genetic material of life." ScienceDaily. ScienceDaily, 8 March 2010. <www.sciencedaily.com/releases/2010/03/100308151043.htm>.
Georgia Institute of Technology. (2010, March 8). Unselfish molecules may have helped give birth to the genetic material of life. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2010/03/100308151043.htm
Georgia Institute of Technology. "Unselfish molecules may have helped give birth to the genetic material of life." ScienceDaily. www.sciencedaily.com/releases/2010/03/100308151043.htm (accessed October 22, 2014).

Share This



More Fossils & Ruins News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Sunken WWII U-Boat That Fired On U.S. Convoy Found

Sunken WWII U-Boat That Fired On U.S. Convoy Found

Newsy (Oct. 22, 2014) U-576, a long-lost German U-boat the U.S. sank in 1942, has been found just 30 miles off North Carolina's coast and near the wreckage of another ship. Video provided by Newsy
Powered by NewsLook.com
Turns Out Jack The Ripper's True Identity Is Still Unknown

Turns Out Jack The Ripper's True Identity Is Still Unknown

Newsy (Oct. 20, 2014) After testing DNA from a shawl found near one of Jack the Ripper's victims, a scientist said he'd identified the killer. New reports refute the claim. Video provided by Newsy
Powered by NewsLook.com
Fish Fossil Shows First-Ever Sex Was Done Side By Side

Fish Fossil Shows First-Ever Sex Was Done Side By Side

Newsy (Oct. 19, 2014) A 380-million-year-old fish may be the first creature to have copulative sex - and it was side by side with arms linked, like square dancers. Video provided by Newsy
Powered by NewsLook.com
As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

As Sweden Hunts For Sub, "Cold War" Comparisons Flourish

Newsy (Oct. 19, 2014) With Sweden on the look-out for a suspected Russian sub, a lot of people are talking about the Cold War, but is it an apt comparison? Video provided by Newsy
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