Stress response and silencing verification of heat shock proteins in Dermatophagoides farinae under temperature stress.

Dermatophagoides farinae is a major exogenous allergen. Its ability to tolerate adverse external temperatures makes it responsible for widespread occurrence of allergies. Heat shock protein (HSP), a recognized temperature stress response gene, but its role in D. farinae remained unclear. Here, we performed a comprehensive study. First, we found that 25 °C was the optimal temperature, and all mites died at 48 or −20 °C for 1 h (LT100). Thus, 41 °C (LT15), 43 °C (LT25), 45 °C (LT45), and −10 °C (LT25) were selected as stress temperatures to perform de novo RNA-seq. Then, 17 main genes of the 47 differentially expressed HSP, were detected by qRT-PCR. Temperature and time gradient versus expression magnitude histogram revealed that HSP70, HSP83-1, HSP83-2, and HSP16-1 showed heat stress response only at 41–43 °C, while HSC71 and HSF played a regulatory role under both heat and cold stress, particularly HSF, with strong intensity, long duration, and quick upregulation at recovery for 10–20 min. Finally, gene expression and D. farinae survival rates significantly decreased following RNAi. These findings indicated that HSPs conferred thermo-tolerance or cold-tolerance to D. farinae. In conclusion, this was the first meaningful exploration that confirmed HSP and HSF playing an important role in temperature resistance of D. farinae.