Spatiotemporal Patterns of Five Small Heat Shock Protein Genes in in Response to Thermal Stress.

(Drury), a destructive polyphagous pest, has been spreading southward after invading northern China, which indicates that this insect species is facing a huge thermal challenge. Small heat shock proteins (sHSPs) function as ATP-independent molecular chaperones that protect insects from heat stress damage. In order to explore the role of sHSPs in the thermotolerance of , five novel sHSP genes of were cloned, including an orthologous gene () and four species-specific sHSP genes (, , , and ). Bioinformatics analysis showed that the proteins encoded by these five contained typical α-crystallin domains. Quantitative real-time PCR analysis revealed the ubiquitous expression of all across all developmental stages of , with the highest expression levels in pupae and adults. Four species-specific were sensitive to high temperatures. The expression levels of were significantly up-regulated under heat stress and increased with increasing temperature. The expression levels of in eggs exhibited an initial up-regulation in response to a temperature of 40 °C. In other developmental stages, the transcription of was immediately up-regulated at 30 °C or 35 °C. transcripts were abundant in the cuticle before and after heat shock. The expression of showed weak responses to heat stress and constitutive expression in the tissues tested. These results suggest that most of the are involved in high-temperature response and may also have functions in the normal development and reproduction of .