Genome Editing of a Deoxynivalenol-Induced Transcription Factor Confers Resistance to Fusarium graminearum in Wheat

Deoxynivalenol (DON) is a mycotoxin virulence factor that promotes growth of the fungus in wheat floral tissues. To further our understanding of the effects of DON exposure on plant cell function, we characterized DON-induced transcriptional changes in wheat spikelets. Four hundred wheat genes were differentially expressed during infection with wild-type as compared with a mutant strain that is unable to produce DON. Most of these genes were more induced by the DON-producing strain and included genes involved in secondary metabolism, signaling, transport, and stress responses. DON induction was confirmed for a subset of the genes, including , by treating tissues with DON directly. Previous work indicates that the ortholog represses trichothecene-induced defense responses and bacterial resistance in , but the role of the NFXL family has not been studied in wheat. We observed greater DON-induced gene expression in a susceptible wheat genotype relative to the -resistant genotype Wuhan 1. Functional testing using both virus-induced gene silencing and CRISPR-mediated genome editing indicated that represses resistance. Together, this suggests that targeting the gene may help to develop disease resistance in cultivated wheat.