An integrated domain in a rice NLR confers specificity for pathogen effector recognition
M. BANFIELD (1) (1) John Innes Centre, United Kingdom

Plant NLRs survey the intracellular environment for the signatures of non-self molecules, typically the presence and/or activity of translocated pathogen effector proteins. They are important tools for traditional and ‘next generation’ disease resistance breeding in globally important crops. Although plant NLRs typically contain three domains, the prevalence of non-canonical domains in these receptors is being realised. Many of these integrated domains (NLR-IDs) may have their evolutionary origin as virulence-associated effector targets that were recombined into NLRs to act as traps or baits. Little is known about how these IDs recognise effectors and enable activation of immune signalling. Recently, we determined the biochemical and structural basis of recognition of the rice blast pathogen (M. oryzae) effector protein AVR-Pik with the rice NLR Pik allele Pikp. Pik alleles each contain an integrated heavy metal associated (HMA) domain that maybe derived from small HMA proteins of rice, the putative effector virulence targets. We revealed a correlation between effector binding affinity to the Pikp-HMA in vitro and in planta immunity readouts. Different Pik alleles of rice show differential binding to members of the AVR-Pik effector family. We have now extended our studies to derive the molecular basis of differential recognition in effector/NLR-ID pairs within this system, and are exploring the potential of engineering NLR-IDs for bespoke recognition capabilities.

Abstract Number: C9-1
Session Type: Concurrent