Mapping effector-triggered immune signalling by quantitative phospho-proteomics

Plant disease resistance (R) proteins enable plants to detect specific pathogen effector molecules, and then activate defence, yet mechanisms of defence activation upon R protein activation (Effector-Triggered Immunity, or ETI) are poorly understood. Arabidopsis RPS4 and RRS1 resistance genes act together to detect two different bacterial effector proteins, AvrRps4 from Pseudomonas sp., and PopP2, an acetyltransferase, from Ralstonia sp. RPS4 is a typical TIR-NB-LRR R protein, but the RRS1 TIR-NB-LRR R protein also carries a WRKY DNA binding domain, that acts as a "bait" that detects the presence and/or activity of AvrRps4 and PopP2 (Williams et al 2014; 10.1126/science.1247357 Sarris et al 2015; 10.1016/j.cell.2015.04.024).
Activation of defence by RPS4/RRS1 results in rapid induction of ~40 ETI genes, including genes for salicylic acid biosynthesis, other defence enzymes and transcription regulators (Sohn et al, 2014 10.1371/journal.pgen.1004655).
The goal of the studentship is to understand how RPS4/RRS1 perception of avrRPS4 is transduced to establish ETI and to identify the signalling components involved. Advanced phospho-proteomics will be at the heart of the project in a close collaboration with the Menke group at TSL