The TRPA1 channel regulates temperature preference in the green peach aphid Myzus persicae

Transient receptor potential (TRP) channels are a class of ion channel proteins that are closely related to thermosensation in insects. They are involved in detecting the ambient temperature and play vital roles in insect survival and reproduction. In this study, we identified and cloned two variants of the TRPA subfamily gene in Myzus persicae, MperTRPA1(A) and MperTRPA1(B), and analyzed their tissue expression by real-time quantitative PCR. Subsequently, these two variants of MperTRPA1 were expressed in the Xenopus oocyte system, and their functions were investigated using the two-electrode voltage clamp technique. The role of the MperTRPA1 gene in temperature adaptation of M. persicae was further determined by RNA interference and a behavioral choice assay to evaluate responses to temperature gradients. The results showed that the MperTRPA1 gene is widely expressed in tissues of M. persicae, with MperTRPA1(A) highly expressed in the mouthparts and MperTRPA1(B) mainly expressed in the antennae. The functional characterization results showed that both variants of MperTRPA1 could be activated and were not desensitized when the temperature increased from 20 to 45°C. The current value and thermal sensitivity (coefficient Q₁₀ value) of MperTRPA1(B) were significantly higher than those of MperTRPA1(A). When the MperTRPA1 gene was knocked down, the behavioral preference of M. persicae for the optimal temperature was reduced and tended to be at a higher temperature, showing a shift in the temperature adaptation range compared to both the wild type and dsGFP-treated M. persicae. In summary, our results elucidated the molecular mechanism of adaptive temperature perception in M. persicae mediated by the thermal sensor MperTRPA1.