Arabidopsis responses to Pseudomonas syringae infection and the emergence of the chloroplast as a key player in innate immunity

Abstract: Successful pathogens attenuate a battery of sophisticated plant defences by deploying a collection of “effector” molecules. Effectors generally function redundantly in planta, targeting multiple levels and nodes of an activated innate immune signalling network.

We have made remarkable progress towards understanding how potential pathogens are recognised by receptor complexes at the host-pathogen interface to activate kinase signalling cascades and transcriptional re-programming which underpin plant innate immunity. However, our knowledge of the signalling processes beyond this is limited.

This seminar will cover our current understanding of the dynamics of activated plant immunity using the Arabidopsis and Pseudomonas syringae pathosystem. Using a combination of genetic, physiological and real-time imaging studies I will describe an emerging role for the chloroplast, a key organelle in primary carbon metabolism and site of synthesis of hormone precursors, in plant innate immunity. I will also examine how pathogen effectors have evolved to collectively target the chloroplast to suppress immunity and promote pathogen multiplication. Time permitting, I will describe ongoing work deploying our existing knowledge to address emerging pathogens of Ash trees and bananas.

Host: Andrea Harper