Project description:Experiment was designed to study the effect of Deformed wing virus (DWV) and the mite Varroa destructor on global gene expression using microarray transcriptional profiling 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.
Project description: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.
Project description:Coumaphos is an acaricide that is widely used to control Varroa mites in bee colonies. However, the extensive use of coumaphos against Varroa has resulted in the development of coumaphos resistant Varroa populations. In this study, the whole genome gene expression profile of 1) a coumaphos resistant V. destructor population (AN-CR) or 2) a coumaphos resistant V. destructor population pretreated with coumaphos (tAN-CR), was compared to the gene expression profile of a susceptible V. destructor population (ATH-S) using Illumina RNAseq.
Project description:Aims of the project is the identification of soluble chemosensory proteins in the olfactory organs of the honeybee mite Varroa destructor. Different families of soluble proteins acting as carriers for odorants have been identified in hexapods, while very limited information is available for other terrestrial Arthropoda. In mites and ticks olfactory organs are located on the distal part of the forelegs and on the capitulum appendages. These two body tagmata and the second pair of legs as control, have been dissected out of phoretics and reproductives Varroa destructor females and protein extracts have been analysed through shotgun proteomics. Protein identification and relative quantification (Label-free quantification, LFQ) has been performed using MaxQuant (version 1.5.8.3). Among the proteins more abundant in appendages bearing chemosensory organs, considering as a model hexapoda soluble olfactory proteins, we have searched for small secreted proteins whose structure include a hydrophobic binding pocket.
Project description:Experiment was designed (i) to analyse the strain composition of Deformed wing virus (DWV) populations in covertly and overtly infected honeybees (Apis mellifera) from Varroa-free and Varroa-infested colonies, and (ii) to determine abundance of the DWV strains following direct injection of the DWV preparations from covertly and overtly infected bees to the bee pupae haemolymph in the absence of Varroa destructor mites. Experiment included isolation of DWV preparations from the following bees: covertly-infected bees from Varroa-free colony, covertly infected bees exposed orally to the Varroa-selected DWV strains, and the overtly infected Varroa-exposed bees. Honeybee pupae were experimentally injected with those DWV preparations and sampled 4 days post injection following development of overt DWV infection. A series of the DWV cDNA fragment covering complete DWV genomic RNA sequences were amplified by RT-PCR using RNA extracted from virus preparations and the injected pupae. The cDNA preparations were sequenced using next generation(Illumina HighSeq 2000) paired-end sequencing to obtain data on the DWV strain composition.
Project description:In this study we addressed whether the transcriptome profile in the honey bee brain is similar for two major parasites of honey bee, Varroa destructor and Nosema ceranae. Honey bees parasitized by these two parasites show accelerated behavioral maturation and deficiences in orientation and learning/memory that we hoped to characterized at the transcriptomic level. honey bee adults infested by Varroa destructor or Nosema ceranae compared to control bees, in duplicate
Project description:The mite Varroa destructor is currently the greatest threat to apiculture as it is causing a global decrease in honey bee colonies. However, it rarely causes serious damage to its native hosts, the eastern honey bees Apis cerana. To better understand the mechanism of resistance of A. cerana against the V. destructor mite, we profiled the metabolic changes that occur in the honey bee brain during V. destructor infestation. Brain samples were collected from infested and control honey bees and then measured using an untargeted liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based global metabolomics method, in which 7918 and 7462 ions in ESI+ and ESI- mode, respectively, were successfully identified. Multivariate statistical analyses were applied, and 64 dysregulated metabolites, including fatty acids, amino acids, carboxylic acid, and phospholipids, amongst others, were identified. Pathway analysis further revealed that linoleic acid metabolism; propanoate metabolism; and glycine, serine, and threonine metabolism were acutely perturbed. The data obtained in this study offer insight into the defense mechanisms of A. cerana against V. destructor mites and provide a better method for understanding the synergistic effects of parasitism on honey bee colonies.
Project description:To study the underlying molecular mechanisms during the Varroa destructor life cycle, we carried out transcriptomic profiling of seven stages: young mites (collected from P8 to P9 brood cells), phoretic mites (collected on adult bees), arresting mites (collected in unsealed L5 brood cells), pre-laying mites (collected from sealed brood cells containing moving larva), laying mites (collected from sealed brood cells containing pre-pupae), post-laying mites (collected from capped brood cells containing purple-eye and white-body pupae P5), emerging mites (collected from P8 to P9 brood cells). In addition, we sampled non-reproducing mites (collected from P5 brood cells, but without offspring), males (collected from P8 to P9 brood cells), and phoretic mites artificially reared in cages with adult bees. This study was performed using Apis mellifera L. honey bee colonies naturally infested by Varroa destructor mites. Adult mites were collected from 4 unrelated colonies.