Presence of thermal hysteresis producing antifreeze proteins in the antarctic mite,Alaskozetes antarcticus

✍ Scribed by Block, William ;Duman, John G.

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 308 KB
• Volume: 250
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402500215

✦ Synopsis

The presence of hemolymph thermal hysteresis antifreeze proteins is described in both the nymphs and adults of the Antarctic oribatid mite, Alaskozetes antarcticus collected from Signy Island in the South Orkney Islands. These proteins, functionally similar to the antifreeze proteins of polar marine fish and certain cold-tolerant insects, lower the freezing point of water by a noncolligative mechanism while not significantly affecting the melting point, thus producing their characteristic thermal hysteresis. This is the first finding of these proteins in mites and the first description of them in an arthropod from the southern hemisphere.

The Antarctic oribatid mite, Alaskozetes antarcticus (Michael), has been the subject of considerable study concerning the nature of its adaptations to the rigors of the terrestrial Antarctic habitat (Block, '77, '80; Cannon and Block, '88). This species is widely distributed throughout the maritime Antarctic, living under stones and on the soil surface in association with algae especially in areas fertilized by seabirds and seals. It is cold-hardy in all its life stages and overwinters as adults and juveniles. The ability