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 A novel socio-ecological approach helps identifying suitable wolf habitats
17.02.2017 | Universität Zürich

nachricht New, ultra-flexible probes form reliable, scar-free integration with the brain
16.02.2017 | University of Texas at Austin

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>