title: NbCSPR underlies age-dependent immune responses to bacterial cold shock protein in Nicotiana benthamiana.
abstract: Plants use receptor kinases (RKs) and receptor-like proteins (RLPs) as pattern recognition receptors (PRRs) to sense pathogen-associated molecular patterns (PAMPs) that are typical of whole classes of microbes. After ligand perception, many leucine-rich repeat (LRR)-containing PRRs interact with the LRR-RK BRI1-ASSOCIATED KINASE 1 (BAK1). BAK1 is thus expected to interact with unknown PRRs. Here, we used BAK1 as molecular bait to identify a previously unknown LRR-RLP required for the recognition of the csp22 peptide derived from bacterial cold shock protein. We established a method to identify proteins that interact with BAK1 only after csp22 treatment. BAK1 was expressed transiently in Nicotiana benthamiana and immunopurified after treatment with csp22. BAK1-associated proteins were identified by mass spectrometry. We identified several proteins including known BAK1 interactors and a previously uncharacterized LRR-RLP that we termed RECEPTOR-LIKE PROTEIN REQUIRED FOR CSP22 RESPONSIVENESS (NbCSPR). This RLP associates with BAK1 upon csp22 treatment, and NbCSPR-silenced plants are impaired in csp22-induced defense responses. NbCSPR confers resistance to bacteria in an age-dependent and flagellin-induced manner. As such, it limits bacterial growth and Agrobacterium-mediated transformation of flowering N. benthamiana plants. Transgenic expression of NbCSPR into Arabidopsis thaliana conferred responsiveness to csp22 and antibacterial resistance. Our method may be used to identify LRR-type RKs and RLPs required for PAMP perception/responsiveness, even when the active purified PAMP has not been defined.
authors.affiliation: Research School of Biology, The Australian National University, Acton, ACT 2601, Australia;
authors.forename: Isabel M L
authors.initials: IM
authors.lastname: Saur
authors.affiliation: The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, United Kingdom;
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kadota
authors.affiliation: The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, United Kingdom;
authors.forename: Jan
authors.initials: J
authors.lastname: Sklenar
authors.affiliation: The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, United Kingdom;
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Holton
authors.affiliation: Gregor Mendel Institute of Molecular Plant Biology GmbH, Austrian Academy of Sciences, 1030 Vienna, Austria.
authors.forename: Elwira
authors.initials: E
authors.lastname: Smakowska
authors.affiliation: Gregor Mendel Institute of Molecular Plant Biology GmbH, Austrian Academy of Sciences, 1030 Vienna, Austria.
authors.forename: Youssef
authors.initials: Y
authors.lastname: Belkhadir
authors.affiliation: The Sainsbury Laboratory, Norwich Research Park, Norwich NR4 7UH, United Kingdom; john.rathjen@anu.edu.au cyril.zipfel@tsl.ac.uk.
authors.forename: Cyril
authors.initials: C
authors.lastname: Zipfel
authors.affiliation: Research School of Biology, The Australian National University, Acton, ACT 2601, Australia; john.rathjen@anu.edu.au cyril.zipfel@tsl.ac.uk.
authors.forename: John P
authors.initials: JP
authors.lastname: Rathjen
mesh_terms: D001426:Bacterial Proteins / Q000276:immunology*; D057773:Cold Shock Proteins and Peptides / Q000502:physiology*; D014026:Nicotiana / Q000276:immunology* / Q000382:microbiology
chemical_list: D001426:Bacterial Proteins; D057773:Cold Shock Proteins and Peptides
keywords: BAK1; Nicotiana benthamiana; PAMP; plant immunity; receptor