Genetic identification and expression analysis of HSPs genes in Phytoseiulus persimilis Athias-Henriot

Heat shock proteins (HSPs) are a class of proteins that are highly expressed in organisms upon exposure to heat stress, and they play a role in protecting cells from heat damage and enhancing cellular thermotolerance. Phytoseiulus persimilis Athias-Henriot is a predatory mite characterized by its voracious appetite and remarkable control abilities against Tetranychus spp. In field applications, P. persimilis frequently encounters hot temperatures during late spring and whole summer. However, it remains unclear whether the HSPs in P. persimilis can facilitate adapt to heat stress. In this study, we assessed the thermal tolerance of P. persimilis in response to different temperatures for hours. At the treatment of 38℃ for 12 hours, the mortality rate reached 47.5%, while all mite died at 42℃ in the same duration. To examine the molecular responses of P. persimilis to thermal stress, we identified 5 HSPs genes from transcriptome dataset by constructing phylogenetic trees. P. persimilis at each life stage and under different stress conditions were collected to evaluate the spatiotemporal expression patterns of HSPs genes by real-time quantitative polymerase chain reaction (RT-qPCR). The RT-qPCR results revealed predominant expression of the HSPs gene in female adult mites, with comparatively lower expression levels in immature stages and males. Following treatment at 38℃ for 12 hours, the expression of the HSPs gene exhibited a gradual increase with extended repair time, peaking at 4 hours before declining. We concluded that the expression of HSPs genes influenced by high-temperature stress may facilitate cellular repair mechanisms in response to adverse environments for P. persimilis.