Chemical changes in DNA can alter the instructions that determine organismal development and function. DNA methylation is one important chemical change that may influence development in response to environmental cues. For example, in honeybees DNA methylation is able to specify an individual?s social form and function. It is hypothesized that DNA methylation is widespread among social insects and may play a general role in the evolution of specialized, social behavior. This research aims to compare the role of DNA methylation in the honeybee and the red imported fire ant, which have separately evolved parallel social systems. DNA sequencing technologies and methylation-sensitive enzymes will be employed to determine the extent to which the patterns and functions of DNA methylation vary in these two species.
This work will highlight the processes that shape DNA methylation patterns in distinct social lineages and will contribute to a greater understanding of the molecular factors that affect gene activity. This will in turn lead to greater knowledge of the factors promoting the success of highly organized social systems. This research will also increase knowledge of the basic biology of the fire ant and the honeybee, the first of which is a serious, invasive pest and the second of which provides crucial agronomic services.
All organisms are capable of developing differently under distinct environmental conditions. This developmental plasticity is critically important because it allows organisms to develop in ways that are appropriate for their survival. Chemical marks on DNA alter the instructions which encode organismal development and function. DNA methylation is one of the most important chemical marks that influences development in response to environmental cues. Our research focused on understanding DNA methylation in a social insect. Social insects, such as ants, bees, wasps, and termites, represent important subjects of study for several reasons. First, many social insects are economically and environmentally significant. The honeybee, for example, helps pollinate economically important crops. And many ants and termites represent damaging invasive species that cause considerable economic harm. Second, social insects display very clear developmental shifts associated with changes in DNA methylation. For instance, social form and function in honeybees is associated with DNA methylation differences. Moreover, it has been hypothesized that DNA methylation is widespread among social insects and may play a general role in the evolution of specialized, social behavior among organisms. Thus, social insects represent key models for understanding how DNA methylation affects development and behavior. This research determined whether DNA methylation was present in the red imported fire ant and investigated whether the targets and function of DNA methylation were conserved between social insect species. Our investigation revealed that DNA methylation was present in the fire ant. We also compared observed patterns of DNA methylation in the fire ant to six additional ant species and found that DNA methylation has broadly conserved targets and functions among insects. Completion of this research yielded important broader impacts in that it involved the training of graduate and undergraduate students in molecular genetic techniques associated with high throughput DNA sequencing, as well as computational methods for analyzing such data. Overall, our research had intellectual merit because it helped illuminate the role of DNA methylation in the regulation of gene function and development.
