NSF Postdoctoral Fellowship in Biology: Understanding how Tripartite Interactions between Insects, Symbiotic Bacteria, and Parasites Influence Infection Outcomes in Insect Vectors

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2023, Broadening Participation of Groups Underrepresented in Biology. The Fellowship supports a research and training plan for the Fellow that will increase the participation of groups underrepresented in biology. Insects commonly form partnerships, known as symbioses, with bacteria. Within their insect hosts, bacterial symbionts can serve a variety of roles from synthesizing essential vitamins to increasing host resistance to heat stress. These bacterial partners can also alter the way insects respond to infection with other microbes—a phenomenon of particular interest for insects that transmit parasites that infect humans, animals, and plants (i.e., insect vectors). However, not all bacterial partners are equal and variation among individual insects as well as parasite strains can further complicate these interactions. This research addresses how variation among insect, bacterial symbiont, and parasite strain influences the outcome of infections in insect vectors. Its outcomes therefore also have implications for human health; the project will also help to address the underrepresentation of certain groups of undergraduates and postbaccalaureates in this important area of scientific inquiry. The Fellow will carry out this research using kissing bugs—vectors of Trypanosoma cruzi, causative agent of Chagas disease—and their symbionts. The Fellow will first assess whether there is specificity in insect-symbiont pairings across kissing bug species and their Rhodococcus spp. symbionts by pairing all possible combinations of insect and bacteria in a full factorial design and assessing insect survival and fecundity as well as bacterial growth and persistence within the insect. Commonly circulating strains of T. cruzi from each kissing bug species’ native range will then be used to challenge the different insect-symbiont pairs to determine which pairings are the least permissive to infection. These data will then be used to determine whether insects, symbionts, parasites, or interactions between the three are driving insect infection outcomes. Concurrently, the Fellow will work to broaden the participation of historically underrepresented groups in science by: (1) providing research opportunities related to the project for undergraduates and post-baccalaureate scholars; and (2) cultivating a regional network of underrepresented scientists across disciplines and career stages. These combined activities seek to increase the recruitment and retention of students from historically underrepresented groups in scientific research. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.