Nbnrp1 Involves Verticillium dahliae Effector PevD1-Induced Defense Responses in Nicotiana benthamiana

PevD1 is a fungal protein secreted by Verticillium dahliae and could induce hypersensitive responses-like necrosis and systemic acquired resistance (SAR) in cotton and tobacco. We previously explored the PevD1 association protein Nbnrp1 in Nicotiana benthamiana and displayed Nbnrp1 positively modulated PevD1-induced cell necrosis and disease resistance. In this study, we further investigated the PevD1-induced immune responses in WT and Nbnrp1-RNAi lines. Moreover, RNA-seq was used to reveal the underlying mechanism of Nbnrp1-modulated PevD1-induced disease resistance in N. benthamiana. The results showed that Nbnrp1-RNAi lines exhibited reduced PevD1-induced immune responses and the silence of Nbnrp1 inhibited the expression of genes related to sesquiterpenoid phytoalexins biosynthesis, which suggested that Nbnrp1 was a positive regulator of PevD1-induced sesquiterpenoid phytoalexins biosynthesis pathway. The research will expand our understandings of mechanisms of PevD1-induced plant immunity.