Heat shock proteins in whiteflies, an insect that accumulates sorbitol in response to heat stress

1. The heat shock response was examined in the silverleaf whitefly. Hsp70 a nd Hsp90 were the major polypeptides synthesized by whiteflies in response to heat stress. 2. The amounts of Hsp70 and Hsp60 protein and Hsp70 mRNA were unchanged in response to a diurnal increase in temperature, whereas sorbitol content inc reased eight-fold. That steady-state levels of Hsps did not increase with h igher rates of synthesis suggests that Hsps turn over faster in heat-stress ed whiteflies. 3. Hsp70 transcript levels were highest when nutrient deprivation accompani ed heat stress. Thus, Hsps appear to be especially important for heat-stres sed whiteflies when sorbitol synthesis is limited nutritionally. (C) 2000 E lsevier Science Ltd. All rights reserved.