CAREER: Impact of Host Radiation on Genome Evolution in Parasites: Microbotryum Hybrids on the Caryophyllaceae

Amherst College, Amherst MA

Investigators

Abstract

Hybridization between disease-causing organisms is often met with great concern despite a critical lack of knowledge about factors that promote such events or the consequences for parasite ecology and evolution. In this project a common disease of plants, caused by the fungus Microbotryum, is used to test whether hybrids are more frequent between parasites from closely related hosts, due partly to the ease of disease transmission across the host boundaries. The potential for parasite hybrids to compete against non-hybrids will then be tested under experimental conditions. By documenting the evolution of chromosome structures, these studies will determine how the genetic instability that is typical of hybrids may be overcome to produce viable parasite lineages with novel genomic properties. Investigation of parasites provides opportunities to study very rapid evolutionary dynamics and species interactions, in addition to being of great importance to preventing human misery cause by disease. More generally, the role of hybridization has been revealed in a broad range of plants and animals, and Microbotryum is a uniquely tractable model to study changes in genome structure. This project will contribute directly into curricular development in areas of genomics and infectious disease and to the training of multiple undergraduate students entering careers in evolutionary biology.