Changing social roles: how manipulating gene expression alters social behaviour in eusocial naked mole-rats

Dr. Melissa Holmes, Associate professor

Mentor: Dr. Melissa Holmes

Dr. Melissa Holmes

Project Description

Naked mole-rats (Heterocephalus glaber, NMRs) are an exceptional species for studying the neural mechanisms of social behaviour. They are eusocial rodents, living in large colonies with strict social roles and the greatest reproductive skew reported in mammals. NMR colonies consist of a ‘queen,’ which is the only reproductive female in the group, 1-3 breeding male consorts, and adult ‘subordinates’ who are all socially suppressed into a pre-pubertal state. Subordinate NMRs can be further divided into ‘worker’ and ‘soldier’ subcastes where workers are generally non-aggressive and take part in colony maintenance while soldiers tend to work less and are highly aggressive towards unfamiliar NMRs. This project tests the hypothesis that individual differences in social phenotype are the result of oxytocin signalling in the prefrontal cortex. We will use adeno-associated viral vectors to up- and down-regulate expression of the oxytocin receptor gene in the prefrontal cortex, and animals will be examined for their interest in and response to unfamiliar individuals. This work will help identify the hormonal and neural circuits that help explain individual differences in social behaviour in a species that lives in large, complex social groups. The SROP student will have the opportunity to both collect and analyze data. They will work exclusively online (all live animal work will be completed by postdoctoral fellow), learning to score diverse social behaviours in a complete experimental sample. The student will also be trained on data analysis and visualization skills working with their own dataset using R.

Mentorship Statement

I believe in an apprenticeship style of mentorship and I apply the philosophies of integration, breadth, and diversity to my mentorship approach. I encourage students to take ownership over their experience. I want them to read and think broadly, to propose ideas, and to see where the data take them. I try to create a learning context that models proficiency and provide direct support as students learn via immersion in authentic activities (e.g., experimental design, troubleshooting, data analyses). Ideally, this culminates in successful independent practice though both success and failure are important. We learn more from failure! To me, the apprenticeship style is holistic whereby the apprentice and the teacher both learn: as the apprentice develops into a peer, their insights feed back to influence the foundation of knowledge that they have been taught. Diversity in all its forms is key to this open exchange of ideas, knowledge, and expertise.

Project ID 613