Unlocking extracellular immunity for new crop protection strategies.

New crop protection strategies are essential to feed a growing world population.

Plant pathogens decrease food production by 18-30% and these losses are expected to increase with climate change and reduced agrochemical use.

Most plant-pathogenic bacteria, fungi and oomycetes colonize the extracellular compartment (apoplast) of plants and are exposed to a vast array of potentially harmful metabolites and hydrolytic enzymes secreted by the plant, providing basal, multigenic immunity that is hardly understood and exploited for crop protection.

Challenges to unlock the potential of this extra layer of immunity reside in: i) the redundancies in the extracellular immune network; ii) adapted pathogens suppressing extracellular immunity; and iii) the research bias towards only a few extracellular immune components.The AIM of the project is to UNLOCK EXTRACELLULAR IMMUNITY for new crop protection strategies.

To do so, I am proposing a radically different approach: to follow the concept that we should study secreted host proteins that are manipulated, uncovered by cutting-edge functional chemical proteomics.With a combination of activity- and reactivity-based probes and crosslinkers, I will display manipulations of secreted proteins from a unique, unbiassed angle and at an unprecedented broad scale, uncovering host targets manipulated by proteins, metabolites and post-translational modifications that are phenotypically hidden by network redundancies and by pathogen-mediated suppressions.

Focussing on conserved host targets that are manipulated by multiple pathogens, and supported by exciting preliminary data and a powerful pathosystem in which both host and pathogen can be manipulated, I will address the challenges and unlock central components of extracellular immunity, for exploitation of this extra layer of immunity in crop protection.