Abnormal development in larvae of Sesamia nonagrioides (Lepidoptera: Noctuidae) resulting from baculovirus-mediated overexpression of a JHE-related gene (SnJHER)

The Mediterranean corn borer Sesamia nonagrioides (Lepidoptera: Noctuidae) has a unique and recently multiplied juvenile hormone esterase gene family (SnJHER) with particular transcriptional profiles and functional characteristics. Unlike conventional juvenile hormone esterase genes (JHEs), the SnJHER gene family seems to have been recently evolved from a common ancestral JHER gene. SnJHERs seem to be regulated by both ecdysone agonists and xenobiotics, while their real role in development remains to be exploited. In this study we transiently expressed the major SnJHER isoform in Bm5 and Hi5 cell lines. The JHER-expressing cell lines showed increased toxicity when treated with the juvenile hormone analog methoprene. Moreover baculovirus-mediated transient gene transduction of the SnJHER gene in larvae of S. nonagrioides resulted in moulting abnormalities. These were more marked after the additional application of the juvenile hormone analog methoprene. Our results indicate a potential mechanism by which SnJHER interferes with normal JHE.