Effector-triggered immunity (ETI) in plants involves a large family of nucleotide-binding leucine-rich repeat (NLR) immune receptors, including Toll/IL-1 receptor-NLRs (TNLs) and coiled-coil NLRs (CNLs). We have focused on the NRG1, a CNL protein that functions as a helper NLR in N-mediated resistance to tobacco mosaic virus (TMV). By introducing mutations into the NRG1 gene in N. benthamiana with CRISPR-Cas9, we demonstrated that NRG1 is a key component that acts downstream of EDS1 to mediate various TNL signaling pathways, including Roq1 and RPP1-mediated HR, resistance to Xanthomonas and Pseudomonas, and XopQ-regulated transcriptional changes.
To further elucidate the molecular mechanisms of NRG1, we are trying to identify NRG1-interaction proteins by yeast two-hybrid screening and co-immunoprecipitation in concert with mass spectrometry. This work will give researchers new insights into the molecular basis of plant immune mechanisms.