Colloquium this week was a special treat as Grace Kunkel defended her Master’s thesis “Investigatingin vivo honey bee toxicology and whole honey bee hive dynamics using fluorescent dyes.” Grace’s work focused on two different levels related to honey bee health: the individual honey bee and the entire honey bee colony.
Collapsing colonies have been in the headlines since 2006, and with finger-pointing at many possible perpetrators. These potential causes of Colony Collapse Disorder (CCD) include bee parasites, bacterial and viral diseases, fungi, poor nutrition, and chemicals (but not cell phones!). While current research suggests that CCD is most likely caused by a combination of these factors, Grace decided to focus on how chemicals may be affecting the honey bees. While the most suspect chemicals include pesticides and fungicides, using these chemicals in experiments is complicated and expensive. As a solution Grace used dyes that were chemically similar to specific pesticides. This allowed her to not only save money, but also easily track the dyes though individual bees and colonies.
When honey bees are exposed to pesticides, proteins called ATP-binding cassette transporters (ABCs) form the first line of defense by actively sequestering the chemicals in the honey bee’s gut to be excreted (Fig. 1). If these ABCs are inhibited, pesticides can build up to dangerously toxic levels in the honey bee’s blood. Grace found that both excretion by ABCs and inhibition of ABCs can be studied in individual honey bees using dyes that mimic the behavior of pesticides. If honey bees encounter ABC inhibitors in their environment, this could sensitize them to pesticides.
About Ryan:Ryan Gott is a PhD student in the lab of Bill Lamp. Ryan studies environmental toxicology and environmental risk assessment with a focus on developing biomarkers for chemicals that interact with ABC transporters.