Iron-Sulfur Cluster Protein NITROGEN FIXATION S-LIKE1 and Its Interactor FRATAXIN Function in Plant Immunity.

Iron-sulfur (Fe-S) clusters are inorganic cofactors that are present in all kingdoms of life as part of a large number of proteins involved in several cellular processes, including DNA replication and metabolism. In this work, we demonstrate an additional role for two Fe-S cluster genes in biotic stress responses in plants. Eleven Fe-S cluster genes, including the - () and its interactor (), when silenced in , compromised nonhost resistance to pv. T1. expression was induced by pathogens and salicylic acid. Arabidopsis () and mutants, with reduced or gene expression, respectively, showed increased susceptibility to both host and nonhost pathogen infection. Arabidopsis and overexpressor lines displayed decreased susceptibility to infection by host pathogen pv. DC3000. The overexpression line exhibited constitutive upregulation of several defense-related genes and enrichment of gene ontology terms related to immunity and salicylic acid responses. Our results demonstrate that NFS1 and its interactor FH are involved not only in nonhost resistance but also in basal resistance, suggesting a new role of the Fe-S cluster pathway in plant immunity.