Understanding the mechanism that regulated social behavior has implications across biology and from basic research to health related concerns. In mammals there is larger body of study on the critical role of the peptide oxytocin in the formation of social recognition and bonds. Here the researchers proposes to examine the insect equivalent, inotocin, to determine if it plays the same role in stimulate parenting and parent-offspring interactions in the subsocial beetle, Nicrophorus vespilloides. This insect has elaborate parental care, including direct regurgitation of food to begging babies, by both males and females. The genome of this beetle has recently been sequenced, and this provides the tools to identify genes that are predicted to play a role in social tolerance, parenting, and pair bonds. The proposed research tests three ideas: 1) genetic pathways can be predicted; 2) sex differences in parenting reflect turning on and off of different genes in the two sexes; 3) the same genes influence social interactions in both parents and their offspring. This research will lead to a greater understanding of the genetics underpinning difference in parenting and how genetics influences social interactions. Developing insect systems to understand genetic influences on social behavior can help identify of genetic problems may lead to asocial behavior, and provide a way to test possible solutions.
This research makes use of candidate gene screens, transcriptomics, and pharmacological manipulations to examine the extent to which genetic influences on social behavior can be and are common across species. A second goal is to examine how sex differences in parenting arise. Finally, if time and resources allow, the extent that social exchanges, such as parent-offspring interactions, involve pleiotropy will be examined. Genes are predicted based on known functions in pathways that are predicted to have been coopted behaviors involved in the evolution of parental care. For example, parenting is predicted to involve a change in mating, aggression and feeding and so genes with known functions in these pathways should also be involved in parenting. This further suggests that genes involved in parenting will be taxonomically independent. Gene expression patterns will be examined in neural tissue from individuals that are not yet parenting, actively parenting beetles, and those that have completed parenting. Patterns of expression will be evaluated with qRT-PCR. Confirmation of the function of genes with significant changes in expression will involve either pharmacological manipulations or RNAi. Sex differences in parenting have been identified with transcrioptomic studies, and these will be verified using qRT-PCR. Gene expression in larvae that are begging and receiving parenting will be examined to test the hypothesis that the same genes involved in parenting are involved in soliciting parenting. In addition to testing these hypotheses, this research provides novel genetic resources for the research community: It also identifies genetic influences on social interactions in a novel context, examining the generality of function of genes influencing social interactions. Finally, this research facilitates comparisons between organisms with increasingly complex parental care and social behavior. In terms of broader impacts, the research will focus on developing human resources of both undergraduate and postgraduate researchers, and develop international collaborations involving students at all stages.
