Project description:We studied the molecular mechanisms underlying the impact of pollen nutrients on honey bee (Apis mellifera) health and how those nutrients improve resistance to parasites. Using digital gene expression, we determined the changes in gene expression induced by pollen intake in worker bees parasitized or not by the mites Varroa destructor, known for suppressing immunity and decreasing lifespan of bees.
Project description:<p>Bee pollen is consumed for its nutritional and pharmacological benefits, but it also contains hazardous allergens which has not been identified. Here, we identified 2 potential allergens, glutaredoxin and oleosin-B2, in <em>Brassica napus</em> (<em>B. napus</em>) bee pollen using mass spectrometry-based proteomics analyses, and used bioinformatics to predict their antigenic epitopes. Comparison of fermented (by <em>Saccharomyces cerevisiae</em>) and unfermented bee pollen samples indicated that glutaredoxin and oleosin-B2 contents were significantly decreased following fermentation, while the contents of their major constituent oligopeptides and amino acids were significantly increased based on metabolomics analyses. Immunoblot analysis indicated that the IgE-binding affinity with extracted bee pollen proteins was also significantly decreased after fermentation, suggesting a reduction in the allergenicity of fermented bee pollen. Furthermore, fermentation apparently promoted the biosynthesis of L-valine, L-isoleucine, L-tryptophan and L-phenylalanine, as well as their precursors or intermediates. Thus, fermentation could potentially alleviate allergenicity, while also positively affecting nutritional properties of <em>B. napus</em> bee pollen. Our findings might provide a scientific foundation for improving the safety of bee pollen products to facilitate its wider application.</p>
Project description:We studied the molecular mechanisms underlying the impact of pollen nutrients on honey bee (Apis mellifera) health and how those nutrients improve resistance to parasites. Using digital gene expression, we determined the changes in gene expression induced by pollen intake in worker bees parasitized or not by the mites Varroa destructor, known for suppressing immunity and decreasing lifespan of bees. bees with or without verroa, and fed or not fed pollen
Project description:Tomato pollen production and viability is highly vulnerable to higher temperature. Hot summers with temperature reaching above 32°C can disrupt production of viable pollens and fruit set, resulting in yield loss. In recent years, temperature above 35-38oC has become a norm during mid-summer with potential adverse impacts on the production of tomatoes and many other crop species. Pollens are developed through the microsporogenesis and micro-gametogenesis stages. The most heat sensitive period is from the meiotic process of the microsporocytes, at the young microspore stage (uninucleate stage of microspore) to during late pollen development (pollen mitosis). This project studied the heat-induced proteomes in microsporocyte, also called pollen mother cells (PMC). Homogenous PMC samples were collected from cross-sectioned frozen fresh anther tissues of tomato ‘Maxifort’ using laser capture microdissection (LCM). Tandem mass tag (TMT) proteomics analysis was conducted to identify proteomics changes related to heat tolerance during pollen development.
Project description:The biochemical and molecular basis of bee pollen under drying stress is not clear. In this study, metabonomics and proteomics were used to study the biochemical regulation and phenolic compound changes in the rape bee pollen of electrohydrodynamic drying. The results show that the direct contribution rate of ionic wind and electric field to drying characteristic parameters was 68.4% and 31.6% respectively. Electric field has a greater effect on the quality parameters. Specifically, compared with ionic wind, ribosome, citric acid cycle and proteasome pathway play a more positive role in regulating the abiotic and biological biochemical responses of electric field dehydration. The protein-phenolic interaction of rape bee pollen during EHD drying led to the change of free phenolic acid content and the differential accumulation of acidmetabolic characteristics such as L-phenylalanine, L-aspartic acid and L-pyroglutamic acid. In addition, TEM observation showed that EHD drying also destroyed the integrity of cell wall structure and tapetum. The results revealed the quality formation mechanism and biochemical regulation strategy of rape bee pollen during processing.