Location: Honey Bee Breeding, Genetics, and Physiology Research
Project Number: 6050-21000-016-020-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Jan 1, 2022
End Date: Nov 30, 2024
Objective:
The overarching goals of this investigation are to 1) test the hypothesis that DWV and IAPV infection of worker honey bees will differentially regulate mRNA of visual genes, such as opsins and 2) test the hypothesis that DWV or IAPV infection will induce physiological changes to eye function that alters visual systems and ultimately, bee foraging behavior.
Specific objectives:
i) Determine the influence of DWV and IAPV infection to transcriptional regulation of genes in the phototransduction pathway;
ii) Determine the functional relevance of DWV and IAPV infections to visual system physiology and the impact covert DWV infections have to perception of color and light;
iii) Test the impact of DWV load to foraging choices at the level of the colony through controlled field studies
Approach:
Understanding physiological mechanisms to enhance honey bee health and mitigate damages induced by viral infections is needed for sustainability of the apicultural industry. One overlooked aspect of pathogen-bee interactions is the influence to the physiological systems that drive foraging behavior, which relies heavily on the visual system. Our data clearly indicate that DWV is capable of infecting the honey bee eye and additional field data indicate possible changes to foraging preference in colonies that have been augmented with DWV. These data, combined with other speculative reports, indicate the physiological systems regulating honey bee vision are altered leading to a change in the visual sensory system. Yet, the specific change to honey bee vision is unknown. Thus, Objective 1 will use transcriptomics to understand how viral infection influences regulation of genes in the phototransduction cascade and this will be combined with histological analyses to determine morphological changes in the honey bee compound eye in response to viral infection. Objective 2 will employ electrophysiological and behavioral assays to fill these gaps in knowledge by quantifying changes to light sensitivity or phototaxis (Obj. 2.1), changes in color spectrum sensitivity (Obj. 2.2), and behavioral attraction to colors (Obj. 2.3). Objective 3 will assess whether these changes relate to field level differences in foraging by examining pollen collection at the colony level for colonies inoculated with virus versus un-inoculated colonies.