Insect Antifreeze Protein Confers Cold Tolerance in Tobacco

Antifreeze proteins (AFPs) refer to a class of polypeptides produced by some animals, plants and bacteria that permit their survival in environments with sub-zero temperature. AFPs play an important role in modifying the shape of ice crystals, inhibition of ice growth and repression of recrystallization.

 A group of scientists from Xianjiang University in China developed cold tolerant transgenic tobacco plants overexpressing a beetle AFP. Low temperature is one of the limiting factors in the growth, productivity and distribution of plants. Higher yields could be achieved either by improving the freezing tolerance of a crop, or by increasing the survival of freezing sensitive plants following light frosts.

The researchers observed that the AFP encoded by MpAFP149 was mainly distributed on the cell wall (in the apoplastic space) of the transgenic tobacco plants. Compared with wild type tobacco, the transgenic plants preserved the integrity of their cell membrane when grown at -1°C for 3 days. The scientists are now looking for ways to introduce the gene into cold sensitive crops such as potato and tomato.

 Read the paper published by Plant Cell Reports at http://www.springerlink.com/content/c181x111323553g3/fulltext.pdf or http://www.springerlink.com/content/c181x111323553g3/?p=42868636ef244dcd8b497e737fea0181&pi=8