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The nuclear pore complex (NPC) comprises more than 30 nucleoporins (Nups). NPC mediates macromolecular trafficking between the nucleoplasm and the cytoplasm, but specific roles of individual Nups are poorly understood in higher plants. Here, we show that the novel nucleoporin unique to angiosperm plants (designated as Nup82) functions in a salicylic acid-dependent defense in a redundant manner with Nup136, which is a component of the nuclear basket in the NPC.Arabidopsis thalianaNup82 had a similar amino acid sequence to the N-terminal half of Nup136 and a Nup82-GFP fusion was localized on the nuclear envelope. Immunoprecipitation and bimolecular fluorescence complementation analyses revealed that Nup82 interacts with the NPC components Nup136 and RAE1. The double knockout mutantnup82 nup136showed severe growth defects, while the single knockout mutantnup82did not, suggesting that Nup82 functions redundantly with Nup136.nup82 nup136impaired benzothiadiazole (an analog of salicylic acid)-induced resistance to the virulent bacteriaPseudomonas syringaepv.tomatoDC3000. Furthermore, transcriptome analysis ofnup82 nup136indicates that deficiency of Nup82 and Nup136 causes noticeable downregulation of immune-related genes. These results suggest that Nup82 and Nup136 are redundantly involved in transcriptional regulation of salicylic acid-responsive genes through nuclear transport of signaling molecules. [ABSTRACT FROM AUTHOR]