Featured Research

from universities, journals, and other organizations

In fly DNA, the footprint of a fly virus

Date:
August 1, 2012
Source:
University at Buffalo
Summary:
In a curious evolutionary twist, several species of a commonly studied fruit fly appear to have incorporated genetic material from a virus into their genomes, according to new research. The discovery could enable research on whether animals hijack viral genes as an anti-viral defense.

Drosophila yakuba, one of several fruit fly species whose DNA appears to harbor genetic material from a virus, according to a University at Buffalo study.
Credit: Photo courtesy of D.J. Obbard, University of Edinburgh

In a curious evolutionary twist, several species of a commonly studied fruit fly appear to have incorporated genetic material from a virus into their genomes, according to new research by University at Buffalo biologists.

The study found that several types of fruit fly -- scientific name Drosophila -- harbored genes similar to those that code for the sigma virus, a fly virus in the same family as rabies. The authors believe the genetic information was acquired during past viral infections and passed on from fruit fly parent to offspring through many generations.

The discovery could open the door for research on why flies and other organisms selectively retain viral genes -- dubbed "fossil" genes -- through evolution, said lead author Matthew Ballinger, a PhD candidate in UB's Department of Biological Sciences.

One hypothesis is that viral genes provide an anti-viral defense, but scientists have had trouble testing this theory because viral genes found in animals are often millions of years old -- ancient enough that the genes' genetic sequence differs significantly from that of modern-day viruses.

The new study, in contrast, uncovered a viral gene that appears to be relatively young, with genetic material closely mirroring that of a modern sigma virus.

"We don't know that these genes have an anti-viral function, but it's something we'd like to test," Ballinger said. "It's tempting to think that these genes are retained and express RNA because there's some kind of advantage to the host."

He and his co-authors -- Professor Jeremy Bruenn and Associate Professor Derek Taylor in UB's Department of Biological Sciences -- reported their results online on June 26 in the journal Molecular Phylogenetics and Evolution. The research, supported in part by UB's Center for Advanced Molecular Biology and Immunology, will also appear in a forthcoming print edition of the journal.

"Our findings establish that sigma virus-like (genes) are present in Drosophila species and that these infection scars represent a rich evolutionary history between virus and host," the researchers wrote in their paper.

Another important contribution the study makes is advancing our understanding of how flies and other organisms acquire copies of virus-like genes in the first place.

The sigma virus belongs to a class of RNA viruses that lack an important enzyme, reverse transcriptase, that enables other viruses to convert their genetic material into DNA for integration into host genomes.

Given this limitation, how did sigma virus genes get into fly genomes?

The new study supplies one possible answer, suggesting that viruses may use reverse transcriptase present in host cells to facilitate incorporation of viral genes into host DNA.

In the genome of one fly, the researchers found a sigma fossil gene right in the middle of a retrotransposon, a genetic sequence that produces reverse transcriptase for the purpose of making new copies of itself to paste into the genome.

The position and context of the viral gene suggests that the retrotransposon made a copying error and copied and pasted virus genes into the fly genome. This is the clearest evidence yet that non-retroviral RNA virus genes naturally enter host genomes by the action of enzymes already present in the cell, Ballinger said.

The study builds on prior research by Taylor and Bruenn, who previously co-authored a paper showing that bats, rodents and wallabies harbor fossil copies of genes that code for filoviruses, which cause deadly Ebola and Marburg hemorrhagic fevers in humans.

The next step in the research is to continue exploring how and why flies and other organisms acquire copies of virus genes. To find out whether sigma virus-like genes have an anti-viral function in fruit flies, scientists could splice the genes into flies that can contract modern sigma viruses, or introduce modern sigma viruses into flies that already harbor the genes.


Story Source:

The above story is based on materials provided by University at Buffalo. Note: Materials may be edited for content and length.


Journal Reference:

  1. Matthew J. Ballinger, Jeremy A. Bruenn, Derek J. Taylor. Phylogeny, integration and expression of sigma virus-like genes in Drosophila. Molecular Phylogenetics and Evolution, 2012; DOI: 10.1016/j.ympev.2012.06.008

Cite This Page:

University at Buffalo. "In fly DNA, the footprint of a fly virus." ScienceDaily. ScienceDaily, 1 August 2012. <www.sciencedaily.com/releases/2012/08/120801132725.htm>.
University at Buffalo. (2012, August 1). In fly DNA, the footprint of a fly virus. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2012/08/120801132725.htm
University at Buffalo. "In fly DNA, the footprint of a fly virus." ScienceDaily. www.sciencedaily.com/releases/2012/08/120801132725.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) 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