Seminarios IHSM La Mayora - Murray Grant (Warwick University, UK)

Abstract: Following a hiatus of 25 years since cloning the first plant disease resistance genes, the past five years have seen remarkable progress in understanding the function of the two classical plant disease resistance (R) protein classes; CNLs and TNLs, characterised by amino terminal coiled-coil and Toll-Interleukin 1 (TIR) domains respectively. Most notable was the discovery that the TIR domain had NADase activity that is essential for effective resistance. My lab studies R signalling dynamics using a combination of whole plant imaging, chlorophyll fluorescence, metabolomics and fluorescent/genetically encoded reporters. We focus the role of the chloroplast and more recently inter-organellular communication in plant immunity, both local and systemic. A new research area addresses the importance of primary metabolism in plant immunity. We present new data revealing unexpected cross-talk between CNLs and TNLs and our attempts to dissect the role of key signalling molecules (H2O2, Ca2+) and primary metabolites (ATP & NAD/P) in plant disease and defence. Finally, we describe additional novel nucleoside derivatives formed by TIR domains that positively or negatively regulate modulate the immune response and how we are trying to functionally dissect these.