Researchers Induce Freezing Tolerance in Fruit Flies
by Bob Yirka
Most of what is known about the ability of some cold blooded animals and several insects to survive having their body temperature fall below freezing has led to the conclusion that those organisms that can do it are unique to the extent that trying to emulate those same abilities or techniques in other organisms is just not feasible.
But that may change now that a team from the Czech Republic has succeeded in partially freezing a fruit fly, and then resurrecting it, using, as they describe in their paper published in the Proceedings of the National Academy of Sciences, a technique copied from a close relative.
Insects that are able to withstand being frozen rely on one of two techniques. They either secrete substances that allow them to control the process of freezing, or they build up proteins that serve as a form of anti-freeze, which prevents their cells from freezing.
In the experiment run by the Czech team, the subarctic fly, Chymomyza costata, was analyzed to see which techniques it uses to survive being frozen for lengthy periods of time. They found it actually used a two step process. First, the fly adjusts its hormones allowing it to stop all cell development, a process called a diapause. Then, it relied on the amino acid proline to help protect it from the effects of subfreezing temperatures…
(read more: PhysOrg) (image: Andre Karwath)
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More information: Conversion of the chill susceptible fruit fly larva (Drosophila melanogaster) to a freeze tolerant organism, PNAS, Published online before print February 13, 2012, http://www.pnas.org/content/early/2012/02/06/1119986109
