Featured Research

from universities, journals, and other organizations

Scientists identify viral gene driving sick gypsy moth caterpillars to climb high and die

Date:
September 8, 2011
Source:
USDA Forest Service ‑ Southern Research Station
Summary:
For a century, scientists have watched European gypsy moth caterpillars infected with a virus use their last strength to do something that a healthy gypsy moth caterpillar would never do in daylight hours -- climb high into a tree and onto a leaf. For scientists, the question has been how does a virus change its host's behavior?

A typical appearance of caterpillars infected with baculovirus, hanging from foliage where they melt and drip virus on foliage below; caterpillar of unknown species.
Credit: Michael Grove

For a century, scientists have watched European gypsy moth caterpillars infected with a virus use their last strength to do something that a healthy gypsy moth caterpillar would never do in daylight hours -- climb high into a tree and onto a leaf. This behavior in infected caterpillars was so consistent that it inspired the term "Wipfelkrankheit," or "tree top disease," to describe the virus that caused it. For scientists, the question has been how does a virus change its host's behavior?

Related Articles


A team of researchers that included a U.S. Forest Service scientist has answered that question. An article in Science published on Sept. 9 identifies a specific viral gene that drives infected caterpillars to die in a way that offers the best potential for spreading the virus that killed it.

The research team was led by Dr. Kelli Hoover of Pennsylvania State University and included Dr. Jim Slavicek, a research biologist with the U.S. Forest Service, Northern Research Station. Team members included other Pennsylvania State University researchers and scientists with the Harvard Medical School.

The discovery provides evidence of a genetic basis for a parasite's ability to have an effect on the host behavior, which scientists call the extended phenotype. "The identification of a specific viral gene that causes the extended phenotype allows other researchers working in this area to narrow their search for the genes that may be responsible in their system," according to Slavicek.

Baculoviruses are viruses that are used to infect and kill the caterpillars of insect pests of trees and crops. One of these viruses kills larvae of the gypsy moth, an urban and forest tree pest in northeastern states that defoliates trees. This virus is specific for the gypsy moth, and consequently will not impact any other insect, animal, or plant in the treatment area. The Northern Research Station and the USDA Animal and Plant Health Inspection Service (APHIS) are partners in producing the virus for states, the National Park Service and other agencies to use to control gypsy moths.

A healthy gypsy moth caterpillar feeds at night and either hides in a tree's bark crevices during the day or climbs down the tree to the soil to avoid predators. For the virus behind tree top disease, there is a significant advantage to a caterpillar dying in the middle of a leaf within the canopy of the tree rather than in a crevice. The dead caterpillar liquefies, releasing millions of virus particles into the environment where they can spread throughout the tree and contaminate other gypsy moth larvae.

Other instances have been identified where parasites and pathogens manipulate host behavior to enhance transmission to new victims. For example, Ophiocordyceps fungus-infected arboreal ants are manipulated into "zombies," inducing them to position themselves in the tree canopy where the microenvironment is ideal for the release of fungal spores and dispersal to new hosts. The doomed "zombie" ants hold themselves in the canopy by clamping down their mighty jaws on a leaf vein.

"Who knew that a virus could change the behavior of its host?" Slavicek said. "Maybe this is why we go to work when we have a cold."


Story Source:

The above story is based on materials provided by USDA Forest Service ‑ Southern Research Station. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kelli Hoover, Michael Grove, Matthew Gardner, David P. Hughes, James McNeil, and James Slavicek. A Gene for an Extended Phenotype. Science, 9 September 2011 DOI: 10.1126/science.1209199

Cite This Page:

USDA Forest Service ‑ Southern Research Station. "Scientists identify viral gene driving sick gypsy moth caterpillars to climb high and die." ScienceDaily. ScienceDaily, 8 September 2011. <www.sciencedaily.com/releases/2011/09/110908145055.htm>.
USDA Forest Service ‑ Southern Research Station. (2011, September 8). Scientists identify viral gene driving sick gypsy moth caterpillars to climb high and die. ScienceDaily. Retrieved January 31, 2015 from www.sciencedaily.com/releases/2011/09/110908145055.htm
USDA Forest Service ‑ Southern Research Station. "Scientists identify viral gene driving sick gypsy moth caterpillars to climb high and die." ScienceDaily. www.sciencedaily.com/releases/2011/09/110908145055.htm (accessed January 31, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Saturday, January 31, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Nanoscale Sensor Could Help Wine Producers and Clinical Scientists

Reuters - Innovations Video Online (Jan. 30, 2015) A nanosensor that mimics the oral effects and sensations of drinking wine has been developed by Danish and Portuguese researchers. Jim Drury saw it in operation. Video provided by Reuters
Powered by NewsLook.com
Dog-Loving Astronaut Wins Best Photo of 2015

Dog-Loving Astronaut Wins Best Photo of 2015

Buzz60 (Jan. 30, 2015) Retired astronaut and television host, Leland Melvin, snuck his dogs into the NASA studio so they could be in his official photo. As Mara Montalbano (@maramontalbano) shows us, the secret is out. Video provided by Buzz60
Powered by NewsLook.com
U.S. Wants to Analyze DNA from 1 Million People

U.S. Wants to Analyze DNA from 1 Million People

Reuters - US Online Video (Jan. 30, 2015) The U.S. has proposed analyzing genetic information from more than 1 million American volunteers to learn how genetic variants affect health and disease. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Rarest Cat on Planet Caught Attacking Monkeys on Camera

Rarest Cat on Planet Caught Attacking Monkeys on Camera

Buzz60 (Jan. 30, 2015) An African Golden Cat, the rarest large cat on the planet was recently caught on camera by scientists trying to study monkeys. The cat comes out of nowhere to attack those monkeys. Patrick Jones (@Patrick_E_Jones) has the rest. Video provided by Buzz60
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:

More Coverage


Gypsy Moth Caterpillars Hormonal Slaves to Virus Gene

Sep. 8, 2011 Gypsy moth caterpillars infected with baculovirus forfeit safety and stay in the treetops during the day because a virus gene manipulates their hormones to eat continuously and forgo molting, ... read more

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