Fusarium elicitor-triggered immunity in model and crop plants

• Applicant: Professor Dr. Ralph Hückelhoven
• Subject Area: Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems ; Plant Breeding and Plant Pathology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 547682052

Understanding the interaction of plants with microbial pathogens is pivotal for managing plant diseases in the field and for improvement of crop plant genotypes to meet the future demand of food security and sustainable productivity. Fusarium species are among the most aggressive fungal pathogens that infect plants, cause yield losses and produce mycotoxins of relevance for human and livestock health. We therefore underwent investigations for enrichment of molecules from Fusarium species, which are immunogenic on plants in the sense that they elicit canonical early immune responses in Arabidopsis thaliana (pattern-triggered immunity, PTI). Finding and partial enrichment of such molecules enabled us to screen for Arabidopsis mutants with reduced immune responses to these elicitors. Based on this screening we successfully identified the cell surface receptor MIK2 as a top candidate for the direct peptide ligand receptor for a new elicitor fraction from fungal pathogens, including Fusarium. We now aim at putting this receptor into more genetic and biological context. We do so by cloning MIK2 orthologs from crop plants for understanding MIK2 conservation in the plant kingdom and compare it to related endogenous SCOOP peptide perception, analysing the cellular nature of enhanced susceptibility of mik2 loss of function mutants and by identification of the actual peptide elicitor molecules from Fusarium spp. and other fungi. This is complemented by targeted MIK2-like gene knock out in tomatoes.

• DFG Programme: Research Grants