Variation in Host Responses to Acquisition of Microbial Partners and Pathogens

Emory University, Atlanta GA

Investigators

Abstract

Most plants and animals are associated with microbial partners that shape their hosts' ability to use environmental resources and to persist under different conditions of stress and disease. These associated benefits select for hosts to maintain these symbiotic partners over generations. While accepting and maintaining beneficial microbes, hosts must also try to attenuate the effects of pathogenic ones. To better understand how animals accomplish this goal, this research characterizes the responses of the pea aphid, Acyrthosiphon pisum, to acquisition of beneficial and harmful bacteria. These insects are ideal candidates for this research because they have a well-studied association with symbiotic bacteria but are also hampered by bacterial pathogens. In this project, variation in susceptibility to pathogens and acceptance of symbionts will be assessed by experimentally measuring these traits in different aphid lineages. Immunological assays will be used to investigate cell-based immune responses, and sequencing technology will be employed to investigate expression of immune response genes. Results will significantly advance our understanding of host susceptibility, immunity and stress in relation to beneficial and harmful microbial associates. Generation of large amounts of genetic data, which will be deposited online at AphidBase and GenBank, will facilitate ongoing annotation of the pea aphid genome, thus providing resources for future studies of a significant agricultural pest. This project will fund training of one graduate student, one postdoctoral researcher, a middle school teacher, and several minority undergraduates. Additionally, results of the research project will be used as the basis for a novel art and science collaboration, in which scientists will work with student artists and minority-serving after school programs to explore how artistic interpretations of scientific results can be used to make research publicly accessible.