Project description:Bees make honey from the nectar that they collect from flowers. The characteristics of honey are closely associated to original botanical species. Compare with sugars in honey, proteins are minor components but usually used as an important honey quality evaluation parameters. Flower-origin proteins could be a good marker for the authentication. However, as a minute component in honey proteome, plant origin proteins are hard to be detected in honey by regular proteomic approaches, such as gel-based techniques. In this study, Eriobotrya japonica Lindl. (loquat) nectar and its derivative monofloral honey were systematically compared, especially regarding the proteomes and enzymatic activities. Using two-dimensional electrophoresis and mass spectrometry, only bee-originated proteins were detected in loquat honey which were major royal jelly proteins and two uncharacterized proteins. Xylosidase, thaumatin, and two kinds of chitinases were detected in loquat floral nectar by the gel-based proteomic approach. To our knowledge, it is the first study to analysis nectar-originated enzymes’ activity in honey and we proposed that the zymography of chitinase is a potential marker for honey botanical origin authentication.
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: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:Our molecular understanding of honey bee cellular stress responses is incomplete. Previously, we sought to identify and began functional characterization of the components of the UPR in honey bees. We observed that UPR stimulation resulted in induction of target genes upon and IRE1 pathway activation, as assessed by splicing of Xbp1 mRNA. However, were not able to determine the relative role of the various UPR pathways in gene activation. Our understanding of honey bee signal transduction and transcriptional regulation has been hampered by a lack of tools. After using RNAseq to expand the known UPR targets in the bee, we use the Drosophila melanogaster S2 cell line and honey bee trans and cis elements to investigate the role of the IRE-1 pathway in the transcriptional activation of one of these targets, the honey bee Hsc70-3 gene. Using a luciferase reporter, we show that honey bee hsc70 promoter activity is inducible by UPR activation. In addition, we show that this activation is IRE1-dependent and relies on specific cis regulatory elements. Experiments using exogenous honey bee or fruit fly XBP1S proteins demonstrate that both factors can activate the Hsc70-3 promoter and further support a role for the IRE-1 pathway in control of its expression in the honey bee. By providing foundational knowledge about the UPR in the honey bee and demonstrating the usefulness of a heterologous cell line for molecular characterization of honey bee pathways, this work stands to improve our understanding of this critical species.