Featured Research

from universities, journals, and other organizations

For Many Insects, Winter Survival Is In The Genes

Date:
May 31, 2007
Source:
Ohio State University
Summary:
Many insects living in northern climates don't die at the first signs of cold weather. Rather, new research suggests that they use a number of specialized proteins to survive the chilly months. These so-called "heat-shock proteins" ensure that the insects will be back to bug us come spring.

The life stages of the flesh fly, from left: pupal stage, adulthood, and larval stage. Researchers studying the flesh fly found that the insect contains a number of genes that allow it to enter a state of arrested development during winter. Nearly all insects carry these genes; without them, the insects would die.
Credit: David Denlinger

Many insects living in northern climates don't die at the first signs of cold weather. Rather, new research suggests that they use a number of specialized proteins to survive the chilly months. These so-called “heat-shock proteins” ensure that the insects will be back to bug us come spring.

Related Articles


A study of flesh flies and a handful of other insects suggests that they have an arsenal of protective heat-shock proteins that are turned on almost as soon as the temperature dips. Until this new study, researchers knew of only two such proteins that were activated in flesh flies during cooler weather.

“Insects need heat-shock proteins in order to survive,” said David Denlinger, the study's lead author and a professor of entomology at Ohio State University. “Without these proteins, insects can't bear the cold and will ultimately die.”

Denlinger and his colleagues found nearly a dozen additional heat-shock proteins that are activated during diapause, a hibernation-like state that insects enter when temperatures drop. Insects can stay in this state of arrested development for several months.

“We certainly didn't expect to find that many proteins active during diapause,” Denlinger said. The researchers report their findings in the current online early edition of the Proceedings of the National Academy of Sciences.

Insects and other animals, including humans, produce heat-shock proteins in response to extremely high temperatures. The proteins are so named because they were initially discovered in fruit flies that were exposed to high heat. Humans make these proteins when we run a high fever.

"But insects make these very same stress proteins during times of low temperature as well as during exposure to high levels of toxic chemicals, dehydration and even desiccation," Denlinger said.

He and his colleagues first figured out how many genes were turned on only during the flesh fly's dormant state. The researchers extracted and compared RNA from both dormant and non-dormant fly pupae – the developmental stage between larva and adulthood. They used a laboratory technique that let them separate out genes that were turned on only in the flies in this dormant state.

The researchers found 11 previously undiscovered genes that turn on heat-shock proteins during diapause. Until this study, they had only known of two such proteins.

Denlinger and his team also examined the expression of one of those previously discovered heat-shock proteins, Hsp70, in five additional insect species that aren't related to the flesh fly. Each insect is a fairly common agricultural pest: the gypsy moth, the European corn borer, the walnut husk maggot, the apple maggot and the tobacco hornworm. Collectively, these species cause millions of dollars of damage annually.

Hsp70 was active while all of the insects were in diapause.

When Denlinger's team knocked out the Hsp70 gene that makes the heat-shock protein, the insects were unable to survive at a low temperature (in this case, insects were exposed to -15C, or 5F.)

“This underscores the essential role of this gene for winter survival, suggesting that this particular heat-shock protein is a major contributor to cold tolerance in insects,” Denlinger said. “It's highly likely that the other heat-shock proteins we found during diapause in the flesh fly are also important to an insect's ability to endure months of cold temperatures.”

Denlinger has no plans to develop a method to get rid of heat-shock proteins in insect pests, but he says that it is important to understand how insects survive through the winter.

“There may be steps we can take to disrupt the diapause process and make an insect vulnerable to low temperatures,” Denlinger said. “At this point, the findings broaden our palette of players that contribute to cold tolerance in insects.”

He said the next step is to figure out the unique functions of each heat-shock protein.

“We assume it's not simply redundancy in the system, but that each protein makes a unique contribution somehow,” Denlinger said. “This protective mechanism is much more complex than we envisioned.”

Denlinger conducted the study with colleagues from Ohio State; the U.S. Department of Agriculture's Agricultural Research Station in Fargo, N.D.; the Harvard School of Public Health; and Liverpool University in the United Kingdom.

Funding for the work came from a USDA-National Research Initiative Grant, the National Science Foundation and the National Institutes of Health.


Story Source:

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


Cite This Page:

Ohio State University. "For Many Insects, Winter Survival Is In The Genes." ScienceDaily. ScienceDaily, 31 May 2007. <www.sciencedaily.com/releases/2007/05/070530124251.htm>.
Ohio State University. (2007, May 31). For Many Insects, Winter Survival Is In The Genes. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2007/05/070530124251.htm
Ohio State University. "For Many Insects, Winter Survival Is In The Genes." ScienceDaily. www.sciencedaily.com/releases/2007/05/070530124251.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Classic Hollywood Memorabilia Goes Under the Hammer

Classic Hollywood Memorabilia Goes Under the Hammer

Reuters - Entertainment Video Online (Nov. 26, 2014) The iconic piano from "Casablanca" and the Cowardly Lion suit from "The Wizard of Oz" fetch millions at auction. Sara Hemrajani reports. Video provided by Reuters
Powered by NewsLook.com
Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Feast Your Eyes: Lamb Chop Sent Into Space from UK

Feast Your Eyes: Lamb Chop Sent Into Space from UK

Reuters - Light News Video Online (Nov. 25, 2014) Take a stab at this -- stunt video shows a lamb chop's journey from an east London restaurant over 30 kilometers into space. Rough Cut (no reporter narration). Video provided by Reuters
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