University of Toronto, Canada
University of Toronto, Toronto, Canada
The Pseudomonas syringae species complex includes a diverse array lineages that can infect numerous agricultural and wild plant species. The recent wide-spread application of next-generation sequencing technology has driven a remarkable expansion in our understanding of the genetic structure of this species complex, yet we still have only a limited understanding of the specific genetic factors underlying niche specificity.
Here we present a comparative and evolutionary genomic analysis over >400 strains of P. syringae, including 62 type and pathotype strains. We specifically focus on the compositional dynamics of the genome, the impact of selection and recombination on genes associated with host adaption, and the use of association tests to identify previously unrecognized genes with host-specific associations. We find that virulence-associated genes are more likely to be recombinogenic and under selection, as well as a strong signal for inter-pathogroup recombination. We argue that this inter-pathogroup recombination of niche-associated genes is critical for maintain genetic cohesion and thereby delimiting the species complex.
Web personal/lab page: guttman.csb.utoronto.ca/