Innate immunity signaling and resistance/fitness outcomes in plants

Mechanisms of surveillance by plants and counter-surveillance by microbes provide a fascinating framework for deciphering host-pathogen coevolution and identifying key disease resistance signaling nodes. We’re studying host recognition of biotrophic pathogens and the processes by which intracellular (NLR) immune receptors, which sense pathogen interference with host processes, transmit recognition to downstream resistance pathways. Using Arabidopsis thaliana as our model system we’re constructing various NLR-programmed defense ‘sectors’ which contribute to immunity and positioning these within the larger environmental stress response network. Arabidopsis also serves as a point of reference for exploring stress network properties in other plant species with different NLR receptor repertoires. I’ll describe recent progress in our analysis of NLR activation and NLR signaling which converge rapidly on the transcriptional machinery to reprogram cells for defense. From these studies, we have developed ideas on how plant innate immunity systems manage to be resilient against rapidly evolving microbial pathogens. We’re also exploring how an interesting NLR receptor ‘Resistance’ gene cluster behaves in a wild Arabidopsis thaliana population. Here we hope to gain insights to evolutionary and ecological forces underlying plant immune receptor maintenance and diversification in nature.