Genome-wide identification of the ADP-ribosylation factor family in wheat and functional characterization of TaARFB1b-A in wheat resistance to fusarium head blight

ADP-ribosylation factors (ARFs) are a highly conserved family of GTP-binding proteins in eukaryotes, involved in regulating vesicle trafficking and cellular signal transduction. Although ARF family proteins have been implicated in plant growth, development, and stress responses, their functions in hexaploid wheat ( Triticum aestivum L.) resistance to Fusarium head blight (FHB) remain largely unknown. In this study, we systematically identified 58 ARF family members in the wheat genome. Phylogenetic analysis classified these members into three subgroups: true ARFs, ARF-like, and SARs. Cis-regulatory element analysis revealed the presence of abundant elements associated with light response, growth and development, abiotic stress, and biotic stress in the promoter regions of TaARF family genes. A triplet gene consisting of three homologous genes, TaARFB1bs ( TaARFB1b-A , T aARFB1b-B and TaARFB1b-D ), was consistently up-regulated in response to Fusarium graminearum and two pathogen-associated molecular patterns (flg22 and chitin). Subcellular localization assays demonstrated that the TaARFB1b-A, TaARFB1b-B and TaARFB1b-D proteins were localized to the plasma membrane, cytoplasm and the nucleus. Simultaneous silencing of TaARFB1bs using a virus-induced gene silencing system in wheat cultivar Shimai 4185 significantly reduced resistance to Fusarium head blight (FHB). Conversely, overexpression of TaARFB1b-A using a virus-mediated overexpression system in Shimai 4185 significantly enhanced resistance to FHB. This study provides theoretical insights and candidate gene resources for further dissecting the biological functions of the TaARF gene family in wheat resistance to FHB.