Inhibition of recrystallization of ice by insect thermal hysteresis proteins: A possible cryoprotective role

Abstract

Thermal hysteresis antifreeze proteins, first discovered in polar marine fishes, are fairly common in overwintering insects where they also help prevent freezing. However, a few species of insects that tolerate freezing also contain these proteins, and in these species the function of the proteins is uncertain. The studies outlined here demonstrate that the thermal hysteresis proteins from the overwintering larvae of the beetle Dendroides canadensis are extremely efficient in inhibiting ice recrystallization. Since recrystallization is a potential source of freezing damage, we suggest that this may be a role of the antifreeze proteins within freeze tolerant insects.