Cold and freezing injury in insects: An overview of molecular mechanisms *

Abstract

The present review discusses the molecular mechanisms of injury caused by low temperatures and/or freezing. Thereview is intended mainly for insect environmental physiologists who focus on the effects of low temperatures. The review successivelydiscusses (1) the effects of low temperatures on the structure and function of macromolecules; (2) the effects of freezingon cells and macromolecules and (3) the mechanisms of damage during thawing and post-thaw. The review shows that injuryprimarily occurs at the molecular level in terms of damage to proteins, nucleic acids and biological membranes. The damage tomacromolecular structures occurs as a result of the interaction between the effects of temperature, ice formation and resultingsecondary effects such as osmotic stress, increased concentration of solutes, cellular freeze dehydration, disruption of ionic balanceand oxidative stress. The present review attempts to identify gaps in our knowledge on the mechanisms of cold injury inorganisms and proposes possible future directions that could contribute to fi lling the gaps.