Role for Transferrin in Triggering Apoptosis in Helicoverpa armigera Cells Treated with 2-Tridecanone

2-Tridecanone, a plant allelochemical present in a large range of tomato species ( Lycopersicon hirsutum f. glabratum), can induce the expression of Helicoverpa armigera transferrin ( HaTrf), which is necessary for insect growth and development. To gain further insight into the mechanism of HaTrf in response to 2-tridecanone, we measured the iron and H₂O₂ levels in the hemolymph during exposure to 2-tridecanone and then explored the effect of transferrin downregulation in a H. armigera fat body cell line exposed to 2-tridecanone. We found that the reduction of HaTrf levels via RNA interference caused rapid apoptotic cell death during exposure to 2-tridecanone. There have been no reports about transferrin genes related to apoptosis induced by plant allelochemicals. Our results indicate that HaTrf mediates the inhibition of apoptotic cell death during exposure to 2-tridecanone and provides insight into the importance of transferrin in the interaction between plants and insects.