Location: Southern Horticultural Research Unit
Project Number: 6062-21430-004-035-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Apr 3, 2023
End Date: Apr 2, 2027
Objective:
Objective 1. Use a nucleoside antibiotic, tunicamycin, to determine whether it can reduce levels of the Deformed Wing Virus infection in honey bee cell cultures while providing an acceptable level of safety/low toxicity for cells.
Objective 2. Prepare small RNA libraries from infected and clean honey bee cells with Deformed Wing Virus and Vairimorpha sp. to catalog differentially expressed microRNAs. Annotate the dataset to identify new and novel differentially regulated bee miRNAs that could significantly mitigate stress.
Approach:
Honey bees (Apis mellifera) are important contributors to global food production and sustain the health of wild flora through their pollination services. Honey bees also support the livelihoods of beekeepers and growers; therefore, it is a priority to keep honey bee hives healthy and productive. Threatening hive health are numerous pathogens, such as Deformed Wing Virus (DWV) and Vairimorpha sp., that are prevalent in hives. This is especially relevant for DWV when the parasitic mite, Varroa destructor, a putative vector of honey bee viruses, is also present in colonies. Deformed Wing Virus and Vairimorpha sp. can have negative effects of hive health, contributing to premature overwintering mortality and imposes a strain on the beekeeping industry to meet pollination demand through replacement of lost hives. Reducing DWV and Vairimorpha sp infections in honey hives is a goal for the beekeeping industry. The use of honey bee cell lines can provide a convenient platform for understanding host-pathogen infection dynamics, as well as testing novel therapeutics aimed at reducing pathogen infection while at the same time be safe for honey bees. In this study, we will assess the role of tunicamycin in depleting the Deformed Wing Virus infection in bees. Our preliminary data show significant Deformed Wing Virus-B (DWV-B) depletion after the sub-lethal dose of tunicamycin (N-glycan inhibitor) in bees. We will use naturally infected honey bee cell lines in the proposed experiments to deplete the viruses. Bee cell lines will be treated with sub-lethal doses of tunicamycin for 48 hrs. Cell lines will be checked for the total DWV-B load using qPCR assay. We expect to see a reduced DWV-B load in treated cell lines. We will also experimentally infect honey bee cell lines with Vairimorpha sp. Small RNA libraries will be synthesized from the infected and clean bee cells to catalog the differentially expressed microRNAs. This experiment will provide a massive dataset to identify new and novel differentially regulated bee miRNAs that could significantly mitigate stress. We will expand these experiments to treat bees to determine the role of tunicamycin in blocking the viral infection in naturally infected honey bees. The results from these experiments will provide an important foundation for protecting bees from viral and microsporidian infections.
