|HAMIDUZZAMAN, MOLLAH MD - University Of Guelph|
|ESSEN, BERNA - Ataturk University|
|HUNT, GREG - Purdue University|
|SUBRAMANYAM, SUBHASHREE - Purdue University|
|TSURUDA, JENNIFER - Clemson University|
|GUZMAN-NOVOA, ERNESTO - University Of Guelph|
Submitted to: Behavior Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/3/2017
Publication Date: 2/3/2017
Citation: Hamiduzzamana, M., Essen, B., Hunt, G.J., Subramanyam, S., Williams, C.E., Tsuruda, J.M., Guzman-Novoa, E. 2017. Differential gene expression associated with honey bee grooming behavior in response to varroa mites. Behavior Genetics. 47(3):335-344. doi:10.1007/s10519-017-9834-6.
Interpretive Summary: Honey bee genes that make the insect resistant to varroa mite infestation have not been well studied. Several genes were discovered that appeared to influence the intensity of honey bee grooming behavior, resulting in better mite removal. The presence or absence of a gene called neurexin-1 may be useful to predict whether a bee population will be resistant and could be used by honeybee geneticists in breeding programs. Breeding for high expression of health-related genes is a viable strategy for academic and industry bee breeders seeking to produce bee lines with built-in resistance to varroa mites and to the viral diseases they spread to bees. This research will benefit bee breeders, professional and hobby bee keepers as well as farmers and honey consumers who prefer control of varroa mites without the use of chemical treatments that can contaminate honey.
Technical Abstract: Honey bee (Apis mellifera) grooming behavior is an important mechanism of resistance against the parasitic mite Varroa destructor. This research was conducted to study associations between grooming behavior and the expression of selected immune, neural, detoxification, developmental and health-related genes. Individual bees tested in a laboratory assay for various levels of grooming behavior in response to V. destructor were also analyzed for gene expression. Intense groomers (IG) were most efficient in that they needed significantly less time to start grooming and required fewer grooming attempts to successfully remove mites from their bodies than did light groomers (LG). In addition, the relative abundance of the neurexin-1 mRNA was significantly higher in IG than in LG, non-groomers (NG) or control (bees without mite). The abundance of poly U binding factor kd 68 and cytochrome p450 mRNAs were significantly higher in IG than in control bees. The abundance of hymenoptaecin mRNA was significantly higher in IG than in NG, but it was no different from that of control bees. The abundance of vitellogenin mRNA was not changed by grooming activity. However, the abundance of blue cheese mRNA was significantly reduced in IG compared to LG or NG, but similar to control bees. Efficient removal of mites by IG correlated with different gene expression patterns in bees. These results suggest that the level of grooming behavior may be related to the expression pattern of vital honey bee genes. Neurexin-1, in particular, might be useful as a bio-marker for behavioral traits in bees.