Abstract text: The plant cell wall is the first defense structure against pathogen attack. Cell wall degrading enzymes, e.g. polygalacturonases (PGs) secreted by fungal pathogens that degrade homogalacturonan, are key virulence factors that on one hand weaken the wall and on the other release oligogalacturonides (OGs), a class of Damage-associated molecular patterns (DAMPs) that activate immunity.

To dissect how cell wall damage and in vivo OG release reshape cellular functions, we generated Arabidopsis thaliana plants expressing a Fusarium PG under an inducible promoter, allowing controlled, time-resolved perturbation of pectin integrity and monitoring of the subcellular proteomic changes. 

Using this system, we investigate how mitochondria- and chloroplast-associated proteomes respond to cell wall breakdown, testing the hypothesis that organellar functions may be targets of CW-derived signalling. Our approach combines native gel electrophoresis to assess alterations in mitochondrial and chloroplastic complexes in induced versus non-induced plants, with shotgun LC–MS/MS proteomics on total protein extracts to identify differentially abundant proteins and pathways associated with defense signalling and stress adaptation. By correlating PG-induced proteomic reprogramming with specific defense-related processes and subcellular compartments, this work provides a framework to connect engineered cell wall damage, OG production and downstream immune and metabolic adjustments in vivo.