, an F-Box-Nictaba Gene, Promotes Plant Growth and Resistance to Black Shank Disease Incited by in .

Black shank, a devastating disease affecting tobacco production worldwide, is caused by . However, few genes related to resistance have been reported in tobacco. Here, we identified , a gene strongly induced by race 0, with a conserved F-box motif and Nictaba (tobacco lectin) domain, in the highly resistant tobacco species . is a typical F-box-Nictaba gene. When it was transferred into the black shank-susceptible tobacco cultivar 'Honghua Dajinyuan', it was found to promote resistance to black shank disease. was induced by salicylic acid, and some resistance-related genes (, , , and ) and resistance-related enzymes (catalase and peroxidase) were significantly upregulated in the overexpression lines after infection with . Furthermore, we showed that actively regulated the tobacco seed germination rate, growth rate, and plant height. The erythrocyte coagulation test of purified NpPP2-B10 protein showed that NpPP2-B10 had plant lectin activity, and the lectin content in the overexpression lines was significantly higher than that in the WT, which could lead to accelerated growth and improved resistance of tobacco. SKP1 is an adaptor protein of the E3 ubiquitin ligase SKP1, Cullin, F-box (SCF) complex. We demonstrated that NpPP2-B10 could interact with the NpSKP1-1A gene in vivo and in vitro through yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC), indicating that NpPP2-B10 likely participates in the plant immune response by mediating the ubiquitin protease pathway. In conclusion, our study provides some important insights concerning mediated regulation of tobacco growth and resistance.