Interaction of Nectarin 4 with a fungal protein triggers a microbial surveillance and defense mechanism in nectar

摘要: Understanding the biochemical mechanisms by which plants respond to microbial infection is a fundamental goal of plant science. Extracellular dermal glycoproteins (EDGPs) are widely expressed in tissues and have been implicated defense responses. Although EDGPs known interact with fungal proteins, downstream effects these interactions poorly understood. To gain insight into phenomena, we used tobacco floral nectar as model system identify mechanism EDGP Nectarin IV (NEC4) functions pathogen surveillance molecule. Our data demonstrates that interaction NEC4 endoglucanase (XEG) promotes catalytic activity V (NEC5), catalyzes conversion glucose molecular oxygen gluconic acid H2O2. Significantly enhanced NEC5 was observed when XEG added or nectarin solutions contain NEC4. This response also purified NEC4:XEG complex NEC4-depleted solutions, did not alone. These results indicate formation key step leading induction nectar, resulting an increase concentrations reactive species (ROS), inhibit growth directly activate signal transduction pathways induce innate immunity responses plant.