Plasma Membrane-Associated Proteins Identified in Arabidopsis Wild Type, lbr2-2 and bak1-4 Mutants Treated with LPSs from Pseudomonas syringae and Xanthomonas campestris

• Published in: Membranes (Basel) Vol. 12; no. 6; p. 606
• Main Authors: Offor, Benedict C, Mhlongo, Msizi I, Dubery, Ian A, Piater, Lizelle A
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 10.06.2022; MDPI
• Subjects: Arabidopsis; Arabidopsis thaliana; Bacteria; BAK1; Binding sites; Biological activity; BPI protein; Data analysis; Gram-negative bacteria; Kinases; LBR2; LC-MS/MS; Ligands; Lipids; Lipopolysaccharides; Liquid chromatography; LPS; LPS-binding protein; MAMPs; Mass spectrometry; Mass spectroscopy; Membrane trafficking; Membranes; Molecular modelling; Mutants; Pathogens; Pattern recognition; Pattern recognition receptors; Perception; Permeability; Phenols; Plant resistance; Proteins; Proteomics; Pseudomonas; Pseudomonas syringae; Receptors; Signaling; T-DNA; Tomatoes; Venn diagrams; Xanthomonas campestris; United States > US; Germany; Arabidopsis thaliana; LC-MS/MS; Xanthomonas campestris; LBR2; Pseudomonas syringae; PRRs; MAMPs; BAK1; LPS
• ISSN: 2077-0375; 2077-0375
• DOI: 10.3390/membranes12060606

Plants recognise bacterial microbe-associated molecular patterns (MAMPs) from the environment via plasma membrane (PM)-localised pattern recognition receptor(s) (PRRs). Lipopolysaccharides (LPSs) are known as MAMPs from gram-negative bacteria that are most likely recognised by PRRs and trigger defence responses in plants. The Arabidopsis PRR(s) and/or co-receptor(s) complex for LPS and the associated defence signalling remains elusive. As such, proteomic identification of LPS receptors and/or co-receptor complexes will help to elucidate the molecular mechanisms that underly LPS perception and defence signalling in plants. The Arabidopsis LPS-binding protein (LBP) and bactericidal/permeability-increasing protein (BPI)-related-2 (LBR2) have been shown to recognise LPS and trigger defence responses while brassinosteroid insensitive 1 (BRI1)-associated receptor kinase 1 (BAK1) acts as a co-receptor for several PRRs. In this study, Arabidopsis wild type (WT) and T-DNA knock out mutants ( and ) were treated with LPS chemotypes from pv. DC3000 ( ) and pv. 8004 ( ) over a 24 h period. The PM-associated protein fractions were separated by liquid chromatography and analysed by tandem mass spectrometry (LC-MS/MS) followed by data analysis using Byonic software. Using Gene Ontology (GO) for molecular function and biological processes, significant LPS-responsive proteins were grouped according to defence and stress response, perception and signalling, membrane transport and trafficking, metabolic processes and others. Venn diagrams demarcated the MAMP-responsive proteins that were common and distinct to the WT and mutant lines following treatment with the two LPS chemotypes, suggesting contributions from differential LPS sub-structural moieties and involvement of LBR2 and BAK1 in the LPS-induced MAMP-triggered immunity (MTI). Moreover, the identification of RLKs and RLPs that participate in other bacterial and fungal MAMP signalling proposes the involvement of more than one receptor and/or co-receptor for LPS perception as well as signalling in Arabidopsis defence responses.