A few years ago, researchers kicked up controversy by proposing to create frost-resistant strawberries by spiking the plants with fish genes-specifically, with the gene for making a protein that helps fish survive in frigid water. While activists reacted strongly against the idea, the real problem was that the scheme just didn't work, because the fish protein didn't lower the fruit's freezing point enough. Researchers have now turned elsewhere in the animal kingdom for plant-defrosting genes with better results. Biologists at Queen's University in Ontario and the University of Alberta have deciphered the structure of two insect "antifreeze proteins" that are up to 100 times more active than the fish proteins.

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