An Insight Into The MicroRNA Profiles of An Ectoparasite Mite Varroa Destructor (Acari: Varroidae), The Primary Vector of Deformed Wing Virus (DWV) of The Honey Bee

Abstract The most important ectoparasite of the honeybee is the remarkably adaptive mite Varroa destructor. The Varroa mite is a competent vector of Deformed Wing Virus (DWV), the Varroa-virus complex is one of the main factors associated with elevated annual honey bee colony mortality. Micro-RNAs (miRNAs) are small, non-coding RNAs of ~22-24 nucleotides, produced by all plants, animals, and viruses that influence biological processes through post-transcriptional regulation of gene expression. Knowledge of miRNAs and their functional role in mite biology remains limited. This study developed small RNA libraries from male and female V. destructor by utilizing Illumina's small RNA-Seq platform. A total of 101,913,208 and 91,904,732 small RNA reads (>18 nucleotides) from male and female mites were analyzed using the mirDeep2 algorithm. A conservative approach predicted a total of 306 miRNAs, of which 18 were upregulated and 13 were downregulated in female V. destructor compared to males. A qPCR assay validated the expression of selected differentially expressed female Varroa miRNAs. This dataset provides a list of potential miRNA targets involved in regulating vital Varroa biological processes and for deciphering new targets against Varroa and honey bee viruses they carry.