NLR immune receptor–nanobody fusions confer plant disease resistance

Plant pathogens cause recurrent epidemics, threatening crop yield and global food security. Efforts to retool the plant immune system have been limited to modifying natural components and can be nullified by the emergence of new pathogen strains. Made-to-order synthetic plant immune receptors provide an opportunity to tailor resistance to pathogen genotypes present in the field. In this work, we show that plant nucleotide-binding, leucine-rich repeat immune receptors (NLRs) can be used as scaffolds for nanobody (single-domain antibody fragment) fusions that bind fluorescent proteins (FPs). These fusions trigger immune responses in the presence of the corresponding FP and confer resistance against plant viruses expressing FPs. Because nanobodies can be raised against most molecules, immune receptor–nanobody fusions have the potential to generate resistance against plant pathogens and pests delivering effectors inside host cells. Description Engineered immune receptors The specificity of plant innate immune receptors cannot rapidly change in response to new pathogens. To increase the diversity of pathogens that plants can sense, Kourelis et al. exploited the specificity and versatility of mammalian antibodies. The authors modified rice-derived receptors that normally perceive fungal pathogen effectors. Part of the receptor protein was swapped with camelid antibody fragments that recognize fluorescent proteins. Plants expressing these chimeric proteins were able to mount an immune response when fluorescent proteins were introduced. The work provides a way forward to rapidly and specifically modify susceptible crop species to provide them with pathogen resistance. —MRS Plant immune receptor–nanobody fusions enable made-to-order disease resistance genes.