Project Number: 6066-21000-001-001-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 2, 2019
End Date: Dec 31, 2022
1. Determine the differential gene expression of Varroa destructor parasitizing honey bee larvae, pupae, and adult using an RNA-Seq approach. RNA-Seq approach will be utilized to determine the differential gene expression in Varroa at organismal level. We will priorities the genes that are involved in the suppression of honey bee immune system. The expression of target genes will be confirmed by qRT-PCR assay. This experiment will identify genes vital for the successful parasitism of honey bee developmental stages. 2. Knockdown the novel differentially expressed Varroa genes using RNA interference to identify new and novel targets to prevent and control varroa infestation. We will knockdown the expression of mite genes/protein families identified in Aim#1 using a novel RNAi technique. Gene silencing will be confirmed by by qRT-PCR. These experiments should provide insight into mite-bee interactions and the identification of vital mite proteins responsible for the successful feeding on the invertebrate host. Additionally, the findings of this project will help to develop strategies to prevent Varroa infestation on honey bee.
The vital significance of honey bees (Apis mellifera) to world food production, and the crucial role of Varroa (V.) destructor to honey bee colony losses make it the most serious ectoparasite. V. destructor is an ectoparasitic mite infests the honey bees by imbibing the hemolymph of larvae and adults. It depletes the host nutritional resources and suppresses their immune system. The mite has also been implicated as a major vector of transmission of a variety of pathogens. The control and prevention of Varroa still remains largely based on chemical acaricides. There is now widespread and increasing resistance to tau-fluvalinate, flumethrin, coumaphos and amitraz, leaving many areas with no effective control measures against Varroa during much of the beekeeping season. The current lack of alternative control methods may undermine the future of sustainable apiculture globally and, hence, general food security. The overall goal is to investigate the Varroa-honey bee interactions to identify new and novel targets to control Varroa infestations. The innovative aspect of this project is that it integrates multidisciplinary cutting-edge tools available in entomology, mite biology, and functional genomics to address the critical knowledge gap in our understanding of mite-bee interactions. This project builds upon the investigation of a largely unexplored field of mite-bee interactions with the aim to dissect the mechanism involved in the suppression of bee immune system and pave the way to develop strategies to control mite infestation in bee hives. The two specific aims are directed at 1) determining the differentially expressed gene in mite, and 2) silence the mite genes by a reverse genetic approach. Methods proposed in this cooperative research agreement have already been standardized in the cooperator's laboratory to study the mite-bee interactions.