Featured Research

from universities, journals, and other organizations

Upending conventional wisdom, certain virus families are ancient

Date:
November 17, 2010
Source:
American Society for Microbiology
Summary:
Certain families of single-stranded DNA virus are more than 40 to 50 million years old, according to new research. The investigators found remnants of circoviruses and parvoviruses in the genomes of diverse vertebrates from fishes to birds and mammals that had been integrated into their genomes at different times from the recent past to more than 50 million years ago.

This electron micrograph depicts a number of parvovirus H-1 virions of the Parvoviridae family of DNA viruses.
Credit: CDC/R. Regnery; E. L. Palmer

Certain families of single-stranded DNA virus are more than 40 to 50 million years old, according to investigators from the Institute for Advanced Study, Princeton, NJ, and the Fox Chase Cancer Center, Philadelphia. The investigators found remnants of circoviruses and parvoviruses in the genomes of diverse vertebrates from fishes to birds and mammals that had been integrated into their genomes at different times from the recent past to more than 50 million years ago.

The research upends the conventional wisdom that most virus families are of very recent origin, and is published in the December Journal of Virology.

"Until recently, age estimates for all viruses except retroviruses were in the thousands of years, and nobody expected to be able to trace viruses beyond that time frame due to high mutation rates of the most commonly circulating viruses," says Anna Marie Skalka of Fox Chase. "We showed that several families have been around for tens of millions of years, and have barely changed over that time frame."

Viruses have long been speculated to be a source of novel animal genes, yet little evidence, except from retroviruses, has supported this idea. The team's motivation included the desire to search for such evidence in other viruses.

"We first scanned all published vertebrate genomes for traces of single stranded RNA (ssRNA) viruses other than retroviruses," says Skalka. The team then used a variety of techniques to devise a new method for determining the age of DNA sequences. "To our amazement, we discovered ancient fossils [viral sequences] in 19 vertebrate species that are related to certain currently circulating RNA viruses," notably the deadly Ebolaviruses, and the Bornaviruses, she says. These results, published earlier this year, encouraged these investigators to look for ancient fossils derived from ssDNA viruses.

"Once again we were amazed to find sequences from replication (rep) and capsid genes from ancient viruses related to the Parvovirus and Circovirus families in 31 of the 49 vertebrate genomes we tested," says Skalka.

While rep proteins from the circoviruses were already known -- some of them selectively kill tumor cells -- the relevant codes were certainly not known to have existed in vertebrates almost as far back as when the dinosaurs roamed earth. Skalka notes that there is no evidence yet that those coding sequences are expressed. "But should a beneficial role for these integrations be found, such as control of cancer progression, it may explain why these viruses were selected for over millions of years of vertebrate evolution."

One additional notable finding is that the timeframe of the viral fossils' appearance, 40-60 million years ago, was a time of rapid accumulation of exogenous and other elements into the genome, including multiple families of viruses, so-called "short interspersed elements" and pseudogenes. That's a curious phenomenon which merits investigating, says first author Vladimir A. Belyi.


Story Source:

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


Journal Reference:

  1. V. A. Belyi, A. J. Levine, A. M. Skalka. Sequences from Ancestral Single-Stranded DNA Viruses in Vertebrate Genomes: the Parvoviridae and Circoviridae Are More than 40 to 50 Million Years Old. Journal of Virology, 2010; 84 (23): 12458 DOI: 10.1128/JVI.01789-10

Cite This Page:

American Society for Microbiology. "Upending conventional wisdom, certain virus families are ancient." ScienceDaily. ScienceDaily, 17 November 2010. <www.sciencedaily.com/releases/2010/11/101116162847.htm>.
American Society for Microbiology. (2010, November 17). Upending conventional wisdom, certain virus families are ancient. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2010/11/101116162847.htm
American Society for Microbiology. "Upending conventional wisdom, certain virus families are ancient." ScienceDaily. www.sciencedaily.com/releases/2010/11/101116162847.htm (accessed April 17, 2014).

Share This



More Plants & Animals News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Change of Diet Helps Crocodile Business

Change of Diet Helps Crocodile Business

Reuters - Business Video Online (Apr. 16, 2014) Crocodile farming has been a challenge in Zimbabwe in recent years do the economic collapse and the financial crisis. But as Ciara Sutton reports one of Europe's biggest suppliers of skins to the luxury market has come up with an unusual survival strategy - vegetarian food. Video provided by Reuters
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com
Thousands Of Vials Of SARS Virus Go Missing

Thousands Of Vials Of SARS Virus Go Missing

Newsy (Apr. 16, 2014) A research institute in Paris somehow misplaced more than 2,000 vials of the deadly SARS virus. Video provided by Newsy
Powered by NewsLook.com
Raw: Three Rare White Tiger Cubs Debut at Zoo

Raw: Three Rare White Tiger Cubs Debut at Zoo

AP (Apr. 16, 2014) The Buenos Aires Zoo debuted a trio of rare white Bengal tiger cubs on Wednesday. (April 16) Video provided by AP
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:
from the past week

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