Assistant Professor of Biological Sciences
Host-Pathogen Evolution, Microbial Genetics, Plant Immunity, Population Genetics
Microbes have an amazing capacity to evolve to colonize new environments. The capacity for rapid adaption is particularly true for plant microbial pathogens as they evolve to circumvent their host’s defenses. Nonetheless, most (if not all) pathogens are restricted in the hosts they can successfully colonize and some pathogens can only colonize single host species.
Our goal is to understand both the evolutionary pressures that select for generalist vs specialist pathogens, as well as the mechanisms underlying adaptation to one vs many hosts. Our research touches upon several disciplines within the Biological Sciences including population genetics, microbial and plant genetics and genomics and classical microbiology. We use a mix of molecular, field and computational approaches to address our questions.
Projects in the lab include:
- Functional genomics of bacterial pathogens to identify genes important for host-specific colonization
- Simultaneous host and pathogen trait mapping to identify evolving resistance and pathogenicity loci
- Identifying range distributions and abiotic factors that influence the spread of pathogens
References (Selected Publications)
- Karasov TL, Almario J, Friedemann C, Ding W, Giolai M, Heavens D, Kersten S, Lundberg DS, Neumann M, Regalado J, et al.: Arabidopsis thaliana and Pseudomonas Pathogens Exhibit Stable Associations over Evolutionary Timescales. Cell Host Microbe 2018, 24:168–179.e4.
- Karasov TL*, Kniskern JM*, Gao L, DeYoung BJ, Ding J, Dubiella U, Lastra RO, Nallu S, Roux F, Innes RW, et al.: The long-term maintenance of a resistance polymorphism through diffuse interactions. Nature 2014, 512:436–440.
- Karasov TL, Chae E, Herman JJ, Bergelson J: Mechanisms to Mitigate the Trade-Off between Growth and Defense. Plant Cell2017, 29:666–680.
- Regalado J, Lundberg DS, Deusch O, Kersten S, Karasov T, Poersch K, Shirsekar G, Weigel D: Combining whole-genome shotgun sequencing and rRNA gene amplicon analyses to improve detection of microbe--microbe interaction networks in plant leaves. ISME J 2020, 1-15