A putative chloroplast Ustilago maydis effector causes morphological changes in Arabidopsis thaliana

Plants have several ways of defending themselves from plant pathogens including physical structures such as thick cuticles and defense hormones such as salicylic acid. The latter induces a cascade of plant defense responses that can ultimately lead to resistance. Similarly, to successfully invade their host, plant pathogens secrete a cocktail of proteins called effectors that favour the virulence of the pathogen. We identified seven candidate effector proteins from the corn smut fungus, Ustilago maydis, that potentially target the maize host’s chloroplasts, which are the organelles where the biosynthesis of salicylic acid happens. The overexpression of these seven potential effectors in the non-host Arabidopsis thaliana led to the foundation of this project. When overexpressed in A. thaliana, I found that one potential chloroplast effector caused a substantial morphological change in the plant, despite no changes in its susceptibility to the bacterial pathogen Pseudomonas syringae pv, maculicola. I plan to use the exchange in Germany to identify the plant interacting partner of this effector protein. This will further our understanding of the role of different effector proteins in causing morphological changes in their host in order to facilitate their development in planta.

Faculty Supervisor:

James Kronstad

Student:

Partner:

The University of Göttingen

Discipline:

Life Sciences

Sector:

Agriculture and Food; Life Sciences (not health); Biotechnology

University:

The University of British Columbia

Program: