RNAi-mediated silencing of SlitPer disrupts sex pheromone communication behavior in Spodoptera litura.

Abstract

The 24-hour circadian rhythm is considered crucial for insect sexual communication. However, its molecular mechanisms and signalling pathways, especially the roles of the clock gene period (Per), remain largely unclear. The sex pheromone communication behavior of Spodoptera litura displays typical circadian rhythm characteristics. Thus, it represents an excellent model for functional analyses of the clock gene Per. In this study, we investigated the potential roles of SlitPer in regulating sex pheromone communication in S. litura using RNAi, qRT-PCR, GC, and behavioral assays. The qRT-PCR results showed that the expression levels of SlitPer and two desaturase genes (SlitDes5 and SlitDes11) in the siPer group significantly differed in most time points from those in the siNC group. The dynamic variation in the three major sex pheromone titers and calling behavior of S. litura females in the siPer group were disordered. In addition, the mating rates of siPer S. litura females significantly decreased by 33.33%. The oviposition of mated siPer females was substantially reduced by 84.84%. These findings provide a fundamental basis for elucidating the molecular mechanism by which Per regulates sex pheromone communication behavior in lepidopteran species. This article is protected by copyright. All rights reserved.