In the Shift from Nurse Bees to Foragers...

Nov 9, 2015

Brian Johnson
Brian Johnson
Rachel Vannette
Rachel Vannette
Have you ever thought about the honey bee colony, the transition of nurse bees to foragers? What all is involved?

There's exciting news today out of the Department of Entomology and Nematology, University of Califoirnia, Davis.

A team of researchers--two faculty members and a graduate student--just published a paper on bee immunity and toxin metabolism today (Nov. 9) in Scientific Reports, part of the Nature Publishing Group. The team: assistant professor Rachel Vannettte; and assistant professor Brian Johnson and his graduate student, Abbas Mohamed.

The journal article is titled Forager Bees (Apis mellifera) Highly Express Immune and Detoxification Genes in Tissues Associated with Nectar Processing

When honey bees shift from nurse bees to foragers, or from caring for the brood to foraging for nectar and pollen, the bees “turn on” gene expression with products that protect against microorganisms and degrade toxins, they discovered,

“First, the results suggest that forager bees may use antimicrobial peptides—short sequences of amino acids with general activity-- to reduce microbial growth in stored food resources,” said Vannette, who joined the faculty in September as assistant professor after a postdoctoral fellowship at Stanford University. “This would be a largely unrecognized way that bees protect honey and potentially other stored resources from microbial spoilage. Second, this work shows that forager bees produce toxin-degrading enzymes in nectar-processing tissues.”

“This may allow forager bees to degrade many different kinds of compounds in nectar, before it is stored,” Vannette said. “Bees also vary in their ability to do this—foragers have a greater ability to degrade a variety of compounds than nurses. This may have implications for hive health and management.” 

The scientists found the change in nectar-processing tissues, but not in the gut.   The scientists surmised that the exposure to bacteria or yeasts in the environment may trigger this change, but they did not examine it in the study. it in the study.

"Nice paper,” said Gene Robinson, director of the Institute for Genomic Biology and Swanlund Chair of Entomology, University of Illinois at Urbana-Champaign, who was not involved in the research. “It had been well known that the division of labor in a honey bee colony is supported by extensive differences in brain gene expression between bees that perform different jobs. This new research shows nicely that this genomic differentiation extends beyond the brain; different complements of active genes in a variety of tissues make each bee better suited for the job it needs to perform."

The team plans to follow up with functional assays to examine the potential of these gene products to (1) reduce microbial growth and (2) degrade a variety of natural and synthetic compounds. 

So, we're anxiously awaiting to hear more!