Multi-omics revealed molecular mechanisms underlying guard cell systemic acquired resistance

ABSTRACT: Systemic Acquired Resistance (SAR) as a plant immune response improves immunity of distal tissue after local exposure to a pathogen. Stomata pores on leaf surfaces are formed by guard cells that recognize bacterial pathogens via pattern recognition receptors. We found that Arabidopsis thaliana plants that have been previously exposed to the pathogenic bacteria Pseudomonas syringae pv. tomato DC3000 (Pst) exhibit an altered stomatal response compared to control plants when systemic leaves are later exposed to the bacteria. Reduced stomatal apertures of SAR primed plants lead to decreases in the number of bacteria that enter the apoplastic space of the leaves. To examine how SAR affects molecular processes in guard cells of distal leaves, we collected Arabidopsis guard cell samples and extracted lipids, metabolites and proteins using a 3-in-1 method. Multi-omic results have revealed molecular components of SAR response specific to the functions of guard cells and roles of ROS and fatty acid signaling in guard cell SAR response. Additionally, our results show an increase in palmitic acid and its derivative 9-PAHSA in primed guard cells. Palmitic acid may play a role as an agonist to Flagellin Sensitive 2 (FLS2), which initiates stomatal closure upon perception of bacterial flagella. The improved understanding of how SAR immune signals affect stomatal movement and immunity can aid biotechnology and marker-based breeding of crops for enhanced disease resistance.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

SUBMITTER: Lisa David  

LAB HEAD: Sixue Chen

PROVIDER: PXD022880 | Pride | 2021-09-09

REPOSITORIES: Pride