Effects of Deformed wing virus infection and the mite Varroa destructor on siRNA and miRNA composition in the honeybee (Apis mellifera)

Experiment was designed to study the effect of Deformed wing virus (DWV) and the mite Varroa destructor on on siRNA and miRNA composition using high-throughput sequencing of small RNA in developing worker honeybee (Apis mellifera). Newly hatched bee larvae (day 3 of bee development) were transferred from a Varroa-free colony with low DWV levels to a Varroa-infested colony with high levels of DWV in bees and Varroa mites. All transferred larvae were receiving the DWV strains present in this Varroa-infested colony with the food delivered by the nurse bees until their capping (day 8). About half of these larvae were capped with Varroa mite and were subjected to the mite piercing and feeding on their haemolymph during pupal development until sampling at purple eye stage (day 14). Exposure to the mite piercing and feeding resulted in about 1000-fold increase of the DWV levels in the majority of the mite-exposed pupae compared to the control pupae and the pupae not exposed to Varroa mites.

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