ELSC Seminar Series

Mating and aggression are innate social behaviors prevalent across mammalian and non-mammalian species. Pursuit of the underlying neural circuitry responsible for these behaviors has been a goal of neuroscientists for decades. Drosophila melanogaster serves as an excellent model system for studying the neural circuits underlying mating and fighting, due to the available genetic toolkit, the near-complete fly connectome, and novel tools for fine quantification of social behaviors in flies.
The courtship ritual in Drosophila melanogaster is multisensory and includes a ‘love song’ who is dynamically changing in response to visual cues from the female. While in D. melanogaster only males sing, both females and nearby males respond to the courtship song.
The ultimate decision – to mate or not to mate – is made by the female, and her responses to male courtship is state-dependent. Recently mated females show aggressive rejecting behaviors towards a courting male.

In my talk, I will present two studies. The first is focused on revealing shared and sexually dimorphic circuits for the response of males and females to courtship song. The second is focused on revealing the neural basis of a persistent aggressive state in the female brain.

We found that males and females are tuned similarly to different parameters of the courtship song, but their behavioral responses to one of two major components of the courtship song (called ‘pulse song’) is sexually dimorphic. We identified a shared ‘feature detector’ for pulse song in the male and female brains and showed that activating this group drives sexually dimorphic responses, suggesting that the sexual dimorphism lies downstream a common ‘feature detector’.
In another study, we found a set of sexually dimorphic cells (called ‘pC1’) whose activation drives persistent changes in female social behaviors: females become more receptive and more aggressive, and both phenotypes outlast the optogenetic stimulation by minutes. Using a volume electron microscopic (EM) image of the female brain and whole-brain two-photon imaging, we found that a group of the pC1 cells are responsible for the aggressive phenotypes and drives minutes long persistent brain activity. Interestingly, this group is reciprocally connected to another set of sexually dimorphic cells who also drive persistent aggression, suggesting that the reciprocal connectivity between the groups may be essential for the persistent activity.

Last, I will show some preliminary data and future directions from my new lab at the University of Haifa, were we aim to reveal the neural basis of social communication in flies.