Cold Adaptation Responses in Insects and Other Arthropods: An “Omics” Approach

Abstract

In this chapter, we review recent genomic, proteomic, and metabolomic studies that link several gene and protein products involved in cold adaptation in insects and other arthropods to energy metabolism and cellular protection mechanisms. Organisms have evolved various mechanisms for survival at subfreezing temperatures. In general, cold hardy invertebrates utilize four main strategies to survive cold temperatures: (1) freeze tolerance, (2) freeze avoidance, (3) cryoprotective dehydration, and (4) vitrification. In addition, many insects in temperate regions overwinter in an arrested developmental state known as diapause, during which they are cold hardy. Major alterations occur during winter diapause, with respect to both total metabolic flux and the relative activities of different metabolic pathways. In these organisms, one such metabolic adaptation to unfavorably cold environmental conditions is the synthesis of cryoprotectants/anhydroprotectants. The metabolic changes and metabolic paths involved in cold adaptation suggest involvement of specific enzymes and key regulatory proteins. These mechanisms of cold adaptation require precise scheduling of the expression of specific genes. Thus, we discuss here the evidence researchers have recently begun to gather supporting a relationship between the genes and proteins of the cold adaptation response and mechanisms of cellular protection and energy metabolism using an “omics” approach.