Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

For many insects, winter survival is in the genes

01.06.2007
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.

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.”

... more about:
»Denlinger »diapause »heat-shock »survive

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 -15°C, or 5°F.)

“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.

David Denlinger | EurekAlert!
Further information:
http://www.osu.edu

Further reports about: Denlinger diapause heat-shock survive

More articles from Life Sciences:

nachricht Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute

nachricht Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>