Synthetic Glycan Ligands for Plant Immune Receptors
Abstract
Wider research context: The demand of current societies, with ever-increasing populations, for food, energy, and materials grows dramatically, resulting in a clear need for increased crop productivity. Crop improvement for food, fiber, and biofuels production will greatly benefit from a more detailed understanding of plant immune function. Plants sense and respond to pathogen attacks by using an arm of the plant immune system that relies on the detection of exogeneous Microbe-Associated Molecular Patterns (MAMPs) and endogenous Danger-Associated Molecular Patterns (DAMPs) by Pattern-Recognition-Receptors (PRRs), such as Receptor-Like-Kinases (RLKs). Despite the large number of RLKs in plants and the dominating presence of glycans in the cell walls of plants, bacteria, and fungi, only a handful of glycans were found to elicit plant immune responses, and only for two of those the cognate receptors have been described. We recently identified two novel glycan-RLK pairs by interrogating glycan arrays with heterologously expressed extracellular RLK domains and further confirmed the immune activities of these glycans in vivo. Objectives: We aim at establishing the plant polysaccharides rhamnogalacturonan-I (RG-I) and galactomannan (GM) as novel DAMPs for activation of plant innate immunity as well as determining the exact molecular patterns recognized by their cognate RLKs. Approach: Chemical synthesis of collections of RG-I and GM oligosaccharides will enable the glycan array-based characterization of recently discovered RG-I- and GM-binding RLKs. After hit validation in further biophysical assays, the identified oligosaccharides will be investigated in vivo towards their potential to stimulate ROS-production, MAP-kinase activation, and defense genes induction as hallmarks of immune activation. Innovation: The unique approach to combine synthetic carbohydrate chemistry and glycan arrays with plant immunity research will enable the elucidation of refined molecular structures with maximum capacity to elicit immune responses. The generated knowledge will facilitate the development of preparations of glycan molecules to boost the plant immune system, avoiding the need for using traditional pesticides.
Publikationen
Project staff
Fabian Pfrengle
Univ.Prof. Dipl.-Chem. Dr.rer.nat. Fabian Pfrengle
fabian.pfrengle@boku.ac.at
Tel: +43 1 47654-77356
Project Leader
01.06.2022 - 31.05.2025