RNA interference reveals allatotropin functioning in larvae and adults of Spodoptera frugiperda (Lepidoptera, Noctuidae)


Submitted: 29 October 2013
Accepted: 13 January 2014
Published: 6 May 2014
Abstract Views: 1172
PDF: 561
Publisher's note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

Authors

The allatotropin of S. frugiperda (Spofr-AT) and its cDNA sequence were characterized 10 years ago, but no functional analyses of the peptide are available. Here we used the RNA interference technique to study the effects of Spofr-AT gene suppression on juvenile hormone (JH) and ecdysteroid titers in the hemolymph of larvae, virgin and mated females, and of males. Spofr-AT gene silencing in last instar larvae resulted in an increase in the amount of JH III and 20-hydroxyecdysone in the hemolymph of the animals, corresponding to an acceleration of the prepupal commitment and transformation to the pupa. Mated females showed much higher JH titers in their hemolymph than virgins and laid almost twice the number of eggs. Spofr-AT gene silencing in freshly ecdysed females led to a further increase in egg production and oviposition, but had only a minor effect on the hemoylmph JH titer. Mated females contain considerable amounts of JH I and JH II in their hemoylmph, which are thought to be received from males during copulation. To confirm this hypothesis, we measured the amount of JH homologs in the male accessory reproductive glands (MARG) before mating and in the bursa copulatrix (BC) of the female after mating. MARG contained high amounts of JH I and JH II, which are transferred to the BC during copulation. One day after mating, JH disappeared from the BC and was then found in the hemolymph of the females. In conclusion, Spofr-AT acts as a true allatotropin in larvae and adults of both sexes of the armyworm.

Supporting Agencies

German Academic Exchange Service (DAAD)

Hassanien, I., Meyering-Vos, M., & Hoffmann, K. (2014). RNA interference reveals allatotropin functioning in larvae and adults of Spodoptera frugiperda (Lepidoptera, Noctuidae). Entomologia, 2(1). https://doi.org/10.4081/entomologia.2014.169

Downloads

Download data is not yet available.

Citations