QBI Neuroscience Seminar: Molecular and neural mechanisms underlying the olfactory modulation of aggression in honeybees
Event Details
Event Contact
Event Description
- Full Description:
- Morgane Nouvian
Queensland Brain Institute, University of Queensland
Title: Molecular and neural mechanisms underlying the olfactory modulation of aggression in honeybees
Abstract: Numerous studies have investigated honeybee aggression and stinging behaviour both in the laboratory and field, including the sensory triggers and the potential regulatory mechanisms. However the specific neural and molecular mechanisms regulating this behaviour are still unknown. In my PhD thesis, I investigated the role of olfactory signals and brain biogenic amines in modulating aggression in honeybees, integrating behavioural, physiological, and pharmacological experiments.
Using a novel assay to measure the stinging behaviour of individual bees under controlled conditions, I first explored whether a range of plant odours could modulate aggression, in particular by interacting with the alarm pheromone released by aroused bees. I identified two floral compounds, linalool and 2-phenylethanol, that blocked the recruitment elicited by the alarm pheromone. Behavioural experiments and in vivo calcium-imaging monitoring the activity of the main olfactory center in the bee brain, the antennal lobe, reveal that these odours do not prevent the bees from perceiving the alarm pheromone. Instead, this blocking effect appears to correlate with the appetitive value of these odours. This suggests that a complex sensory integration takes place when honeybees are faced with the decision of engaging or not into defensive tasks. Furthermore, a field test demonstrated that linalool could also be used to manage aggressive colonies, highlighting the practical application of these findings.
I also investigated the role of brain biogenic amines in honeybee aggression. Biogenic amines are important neuromodulators and have been implicated in the regulation of the aggressive behaviour of a number of species. However, their potential role in regulating the honeybee’s stinging behaviour had not been investigated so far. By measuring biogenic amine levels in different brain regions of bees that were tested for their aggressiveness, I found that high serotonin and dopamine levels correlated with high aggressiveness and/or exposure to the alarm pheromone (depending on the brain region). Pharmacologically increasing the level of these two amines induced higher aggressiveness in bees, while antagonistic treatments decreased aggressiveness. This confirms the key role of serotonin and dopamine in regulating honeybee aggression.
Directions to UQ
Event Tools
Share This Event
Print
Email
Share
Rate This Event
Tweet This Event
Calendar Tools
Featured Calendars
Subscribe via RSS