RT Journal Article SR Electronic T1 Immune receptors with exogenous domain fusions form evolutionary hotspots in grass genomes JF bioRxiv FD Cold Spring Harbor Laboratory SP 100834 DO 10.1101/100834 A1 Paul C. Bailey A1 Gulay Dagdas A1 Erin Baggs A1 Wilfried Haerty A1 Ksenia V. Krasileva YR 2017 UL http://biorxiv.org/content/early/2017/01/20/100834.abstract AB Understanding evolution of plant immunity is necessary to inform rational approaches for genetic control of plant diseases. The plant immune system is innate, encoded in the germline, yet plants are capable of recognizing diverse rapidly evolving pathogens. Plant immune receptors (NLRs) can gain pathogen recognition through point mutation, recombination of recognition domains with other receptors, and through acquisition of novel ‘integrated’ protein domains. The exact molecular pathways that shape immune repertoire including new domain integration remain unknown. Here, we describe a non-uniform distribution of integrated domains among NLR subfamilies in grasses and identify genomic hotspots that demonstrate rapid expansion of NLR gene fusions. We show that just one clade in the Poaceae is responsible for the majority of unique integration events. Based on these observations we propose a model for the expansion of integrated domain repertoires that involves a flexible NLR ‘acceptor’ that is capable of fusion to diverse domains derived across the genome. The identification of a subclass of NLRs that is naturally adapted to new domain integration can inform biotechnological approaches for generating synthetic receptors with novel pathogen ‘traps’.