British scientists have developed polymer alternatives to DNA and RNA — the molecular architecture of life on Earth — that could lead to improvements in medicine and nanotechnology.
DNA forms the template that contains all the information necessary to create an organism, writes Eryn Brown for Los Angeles Times via BostonHerald.com. RNA takes that information and translates it into proteins, the building blocks of life.
Researchers at the Medical Research Council (MRC) Laboratory of Molecular Biology in the United Kingdom found a way to use polymers to function the same way as DNA and RNA, and replicated copies of them, reports Today. The scientists called the new molecules, XNA, X standing for “xeno,” a Greek prefix meaning “strange,” “foreign,” or “alien.” The findings were reported in the journal Science.
Researchers made XNA building blocks to six different genetic systems by replacing the natural sugar components found in DNA with six different polymers, reports Christine Dell’Amore of National Geographic News. The team then evolved enzymes that can make XNA from DNA and others that changed XNA back into DNA.
“There is no overwhelming functional imperative for life to be based on DNA or RNA,” says Phil Holliger from the MRC Laboratory in Cambridge, who led the team, reports Chemistry World. “Other polymers can perform these functions, at least at a basic level.”
The research may provide a new way of developing designer nucleic-acid drugs that could resist breakdown or have other desirable properties, such as the ability to slip from the bloodstream into diseased cells. Specifically, the researchers created XNA fragments that could bind to molecular targets in the HIV virus. This ability could create a new platform for creating targeted drugs to treat diseases.
XNA-based drugs “might have a future to rival antibodies,” says Dr. Holliger. Antibody drugs are used to treat cancer and autoimmune diseases. However, they are difficult to develop and produce.
The research also poses questions about how life could be created in other parts of the universe. The findings could help scientists figure out how DNA and RNA became so crucial in the evolution of life on Earth and even help in the search for extraterrestrial organisms, says Dr. Vitor Pinheiro, a co-author of the paper. “If a genetic system doesn’t have to be based on DNA and RNA, what then do you define as life?” he asks.
Source: “Researchers Make Alternatives to DNA and RNA,” BostonHerald.com, 4/21/12
Source: “A Big Step ‘Closer to Artificial Life,’” Today, 4/21/12
Source: “Synthetic DNA Created, Evolves on Its Own,” National Geographic News, 4/19/12
Source: “Polymers Perform Non-DNA Evolution,” Chemistry World, 4/19/12
Image by Michael Ströck, used under its Creative Commons license.
Dale McGeehon has been a journalist and editor for more than 25 years, covering chemical regulation and testing for Pesticides and Toxic Chemical News and innovations in material sciences for the National Technology Transfer Center. His writing credits include Omni and College Park magazines and The New York Times.
