Being in Biology right now we are learning about proteins so I looked into the proteins that keep plants from freezing in harsh Alaskan winters. I found an article titled “Antifreeze proteins enable plants to survive in freezing conditions” by RAVI GUPTA and RENU DESWAL. I was intrigued by the fact that this article came out of India, where I imagine they do not get cold weather like maybe a northern European country, where I would expect an article like this to come from. The article goes into depth of how the proteins impede the hydrogen bonds of the water molecules so that they cannot bond and form ice crystals.
“Overwintering plants secrete antifreeze proteins to provide freezing tolerance. These proteins bind to and inhibit the growth of ice crystals that are formed in the apoplast [conduit for water transport in plants where water moves through the cell walls without going through the inner cell membrane] during subzero temperatures. Antifreeze activity has been detected in more than 60 plants and antifreeze proteins have been detected in 15 of these, including gymnosperms, dicots and monocots.
The main function of antifreeze proteins is inhibition of ice crystal growth rather than the lowering of freezing temperatures. Antifreeze activity with higher Thermal hysteresis also exists in plants. Calcium and hormones like ethylene and jasmonic acid have been shown to regulate plant antifreeze activity. Plant antifreeze proteins may have evolved nearly 36 million years ago”.
Gupta, R. and R. Deswal. 2014. Antifreeze proteins enable plants to survive in freezing conditions.J Biosci. 39(5):931-44.