Identification of transient receptor potential channel genes and functional characterization of TRPA1 in Spodoptera frugiperda

Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities. Transient receptor potential(TRP) channels, which constitute a vast ion channel family,play pivotal roles in sensing the external environment and maintaining internal homeostasis in insects. TRP channels have been widely investigated for their critical roles in regulating various insect behaviors in recent years.In this study, we identified 15 TRP gene loci encoding 26 transcripts in the genome of S. frugiperda and analyzed their expression profiles at different developmental stages. The results revealed that S. frugiperda possesses four TRPC genes, six TRPA genes, one TRPM gene, two TRPV genes, one TRPN gene, and one TRPML gene, while a canonical TRPP is absent. Moreover, the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression system. The results showed that SfruTRPA1 is activated by temperature increases from 20 to 45°C,and there is no significant desensitization after repeated stimuli within the same temperature range. Additionally,SfruTRPA1 is activated by certain natural chemicals, including allyl isothiocyanate(AITC) and cinnamaldehyde(CA).These findings provide valuable insights to the TRP genes in S. frugiperda.