Rhodopseudomonas palustris Quorum Sensing Molecule pC-HSL Induces Systemic Resistance to TMV Infection via Upregulation of NbSIPK/NbWIPK Expressions in Nicotiana benthamiana

G-negative bacteria produce myriad N-acyl-homoserine lactones (AHLs) that can function as quorum sensing (QS) signaling molecules. AHLs are also known to regulate various plant biological activities. p-Coumaroyl-homoserine lactone (pC-HSL) is the only QS molecule produced by a photosynthetic bacterium, Rhodopseudomonas palustris. The role of pC-HSL in interaction between R. palustris and has not been investigated. In this study, we investigated effect on immunity found induce systemic resistance Tobacco mosaic virus (TMV) infection Nicotiana benthamiana. results show treatment prolong activation two mitogen-associated protein kinase genes (i.e., NbSIPK NbWIPK) increase expression transcription factor WRKY8 well immune response marker NbPR1 NbPR10, leading an increased accumulation reactive oxygen species (ROS) TMV-infected plants. Our activities ROS-scavenging enzymes, peroxidase superoxide dismutase. Knockdown or NbWIPK N. benthamiana plants through virus-induced gene silencing nullified attenuated pC-HSL–induced resistance, indicating functioning relies activity those kinases. Meanwhile, pC-HSL–pretreated showed strong induction after TMV inoculation. Taken together, our demonstrate increases infection, which helpful uncover outcome its host