Comparative profiling of microRNAs and their association with sexual dimorphism in the fig wasp Ceratosolen solmsi.

microRNAs (miRNAs) are small noncoding RNAs that regulate various biological processes, including insect metamorphosis and sexual dimorphism. The fig-pollinating wasp, Ceratosolen solmsi, is a member of the super family Chalcidoidea, which have mutualistic relationships with their fig tree hosts. C. solmsi exhibits extreme sexual dimorphism, which corresponds to the distinct lifestyles of both sexes. Our previous studies showed that these dimorphic characteristics are associated with a dimorphic gene expression pattern. In this study, we constructed six small RNA libraries from female and male wasps in three different developmental stages, i.e., larvae, early pupae, and late pupae. We detected known miRNAs and predicted novel miRNAs, and compared their expression patterns in both sexes and among different developmental stages. We focused mainly on the miRNAs with significantly different expression patterns between sexes and among different life stages, as well as their putative associations with metamorphosis and the formation of sexual dimorphism.