Social interactions are crucial to the proper development and health of individuals, but the genetic and neural bases of social behavior are still poorly understood.

 

We are interested in determining the neurogenetic mechanisms by which animals respond to the presence of another similar individual, from perception to integration and decision making: how does an animal decide what to do with the information that an other individual is nearby? What are the neurogenetic circuitries underlying social interactions?

 

We have made significant contributions to this question, using Drosophila melanogaster. We developed powerful behavioural assays - social space and avoidance of stressed individuals - allowing for powerful quantification of social interactions, and determination of the underlying neural circuits.

​

Our studies of social spacing in Drosophila melanogaster in the past five years have led to the observations that social spacing is indeed not random (Simon, et al., 2012, McNeil, et al., 2015), and changes in response to social experience (such as mating and isolation (Simon, et al., 2012). In term of modalities, vision, but not classical olfaction is necessary for social spacing (Simon, et al., 2012). From my findings and that of others, a neural circuit involving dopaminergic signalling (Fernandez, et al., 2017) and cholinergic neurons of the mushroom body (Burg, et al., 2013) - possibly downstream of those dopamine neurons - is emerging as a modulator of social spacing. At the synaptic level, we have shown that Neurobeachin (an anchor protein, Wise, et al., 2015) and Neuroligin (a cell adhesion protein, Robinson, et al., 2017, Yost, et al., 2017) are implicated in social space, as well. Both of those postsynaptic proteins have human homologues that are candidate genes for autism. Finally we found that BPA, a toxin that is known to affect proper neurodevelopment and is linked to autism, also leads to abnormal social spacing (Kaur, et al., 2015).

 

More recently, we made a fascinating discovery: the age of the parents alter social space: the progeny of old flies behave as their parents, and are further apart (Brenman-Suttner, et al., 2018). This transgenerational effect is particularly relevant, as recent studies have linked neuropsychiatric disorders such as Autism Spectrum Disorders (ASDs) and Schizophrenia to old fathers. These disorders often include changes in social behaviours such as inappropriate social distance, and we demonstrated that both social space and transgenerational effects that mediate it are effectively modeled in Drosophila melanogaster.

 

In another type of response to social cues, flies strongly avoid the volatile substance dSO emitted by stressed flies (Fernandez, et al., 2014). CO2 has been identified as one of the compounds in dSO (Suh, et al., 2004), although other unidentified compound(s) are required to elicit the full avoidance of dSO (Suh, et al., 2004). Because dSO is emitted by stress flies and causes a response from conspecifics, it is considered a social cue. Compared to social space, dSO avoidance requires different sensory modalities such as olfaction (Fernandez, et al., 2014). Further, dopaminergic neuromodulation is not involved (Fernandez, et al., 2017). Finally, in collaboration with Dr. Jeremy McNeil, two students, Ian McDonalds, and Ryley Yost (who did his honour thesis in 2016/17 with me and is now a graduate student in my lab), found that only a very light stress is enough to elicit a strong dSO avoidance response by the flies, potentially influencing flies in all sort of behavioural assays performed in typical Drosophila research laboratories (Yost, et al., In preparation).

​

​

Our research falls two main umbrellas:

​

1. Understanding basic Behavioural Genetics questions: pursuing the neurogenetic characterisation of social behaviours in Drosophila

Jade, Ryley

 

2. Take advantage of these simple behavioural paradigms and use them as diagnostic tools to elucidate conserved pathways underlying candidate genes or environmental conditions affecting human behaviours, in order to identify potential targets for drug discovery

Wes, Zac, and Yen