Project description:The microsporidia Nosema ceranae are intracellular parasites that proliferate in the midgut epithelial cells of honey bees (Apis mellifera). To analyze the pathological effects of those microsporidia, we orally infected honey bee workers 7 days after their emergence. Bees were flash frozen 15 days after the infection. Then, the effects on the gut ventriculi were analyzed and compared to non-infected (control) bees. Comparisons of control vs Nosema ceranae bees
Project description:The microsporidia Nosema ceranae are intracellular parasites that proliferate in the midgut epithelial cells of honey bees (Apis mellifera). To analyze the pathological effects of those microsporidia, we orally infected honey bee workers 7 days after their emergence. Bees were flash frozen 15 days after the infection. Then, the effects on the gut ventriculi were analyzed and compared to non-infected (control) bees.
Project description:Experimental infection of (2 days old) adult honey bee workers (30 bees per replicates, 3 replicates per treatments, from 3 different colonies (one colony per cage for each treatment)) with 10^9 genome equivalent of Black Queen Cell Virus (BQCV) in 10µl of sugar solution and/or 10^5 fresh Nosema ceranae spores (control bees were given a similar bee extract in PBS, without pathogen). Bees were kept in cages of 30 bees in incubator (30°C/50%RH). At day 13 p.i., bees were flash frozen, and stored at -80°C.
Project description:Experimental infection of (2 days old) adult honey bee workers (30 bees per replicates, 3 replicates per treatments, from 3 different colonies (one colony per cage for each treatment)) with 10^9 genome equivalent of Black Queen Cell Virus (BQCV) in 10µl of sugar solution and/or 10^5 fresh Nosema ceranae spores (control bees were given a similar bee extract in PBS, without pathogen). Bees were kept in cages of 30 bees in incubator (30°C/50%RH). At day 13 p.i., bees were flash frozen, and stored at -80°C. Brain mRNA profiles of 15 old bees were generated by deep sequencing, in triplicates except for bees infected by both Nosema ceranae and Black Queen Cell Virus (duplicates)
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: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.
Project description:We aim to evaluate the effects of four Nosema spores’ isolates, (i) and (ii) N. ceranae isolated from A. mellifera hosts from two different geographical origins, (iii) N. ceranae from A. cerana host and (iv) N. apis from A. mellifera, on the A. mellifera on gut proteomics at the early stage of infection. To dissect the molecular mechanism responsible of the susceptibility of A. mellifera to Nosema, we investigated by high-resolution proteomics (LC-ESI-MS/MS) and differential label-free quantification of proteins (LFQ) the molecular cross-talk existing between different species and isolates of N. apis and N. ceranae, and the targetted gut tissue of A. mellifera. To reach the objectives of this study, we performed a bottom-up proteomic analysis on the different anatomical sections of the gut tissue (esophagus, crop, midgut, ileum and rectum) at an early stage of the exposition to Nosema spores (4 days). Then, we focused on the midgut, the region targeted by Nosema sposres for germination and, as we found out, the second region with the highest load of Nosema proteins, after the rectum, to perform differential quantitative proteomic analyses and acquire series of up- and down-regulated proteins. We discussed the different pathways observed to be impacted by different Nosema species and isolates with a main focus on the deregulated metabolic and response to stimuli processes.
Project description:Purpose: Parts of Europe and the United States have witnessed dramatic losses in commercially managed honey bees over the past decade to what is considered an unsustainable extent. The large-scale loss of honey bees has considerable implications for the agricultural economy because honey bees are one of the leading pollinators of numerous crops. Honey bee declines have been associated with several interactive factors. Poor nutrition and viral infection are two environmental stressors that pose heightened dangers to honey bee health. Methods: We used RNA-sequencing to examine how monofloral diets (Rockrose and Chestnut) and Israeli acute paralysis virus inoculation influence gene expression patterns in honey bees. Results: We found a considerable nutritional response, with almost 2,000 transcripts changing with diet quality. The majority of these genes were over-represented for nutrient signaling (insulin resistance) and immune response (Notch signaling and JaK-STAT pathways). Somewhat unexpectedly, the transcriptomic response to viral infection was fairly limited. We only found 43 transcripts to be differentially expressed, some with known immune functions (argonaute-2), transcriptional regulation, and muscle contraction. We created contrasts to determine if any protective mechanisms of good diet were due to direct effects on immune function (resistance) or indirect effects on energy availability (tolerance). A similar number of resistance and tolerance candidate differentially expressed genes were found, suggesting both processes may play significant roles in dietary buffering from pathogen infection. We also compared the virus main effect in our study (polyandrous colonies) to that obtained in a previous study (single-drone colonies) and verified significant overlap in differential expression despite visualization methods showing differences in the noisiness levels between these two datasets. Conclusions: Through transcriptional contrasts and functional enrichment analysis, we add to evidence of feedbacks between diet and disease in honey bees. We also show that comparing results derived from polyandrous colonies (which are typically more natural) and single-drone colonies (which usually yield more signal) may allow researchers to identify transcriptomic patterns in honey bees that are concurrently less artificial and less noisy. Altogether, we hope this work underlines possible merits of using data visualization techniques and multiple datasets when interpreting RNA-sequencing studies.