title: Salmonella enterica flagellin is recognized via FLS2 and activates PAMP-triggered immunity in Arabidopsis thaliana.
abstract: Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Recent evidence indicates that plants recognize S. enterica and raise defense responses. Nonetheless, the molecular mechanisms controlling the interaction of S. enterica with plants are still largely unclear. Here, we show that flagellin from S. enterica represents a prominent pathogen-associated molecular pattern (PAMP) in Arabidopsis thaliana, which induces PAMP-triggered immunity (PTI) via the recognition of the flg22 domain by the receptor kinase FLS2. The Arabidopsis fls2 mutant shows reduced though not abolished PTI activation, indicating that plants rely also on recognition of other S. enterica PAMPs. Interestingly, the S. enterica type III secretion system (T3SS) mutant prgH- induced stronger defense gene expression than wild-type bacteria in Arabidopsis, suggesting that T3SS effectors are involved in defense suppression. Furthermore, we observe that S. enterica strains show variation in the flg22 epitope, which results in proteins with reduced PTI-inducing activity. Altogether, these results show that S. enterica activates PTI in Arabidopsis and suggest that, in order to accomplish plant colonization, S. enterica evolved strategies to avoid or suppress PTI.
authors.affiliation: Unité de Recherche en Génomique Végétale (URGV), UMR INRA/CNRS/Université d'Evry Val d'Essonne, 91057 Evry, France.
authors.forename: Ana Victoria
authors.initials: AV
authors.lastname: Garcia
authors.forename: Amélie
authors.initials: A
authors.lastname: Charrier
authors.forename: Adam
authors.initials: A
authors.lastname: Schikora
authors.forename: Jean
authors.initials: J
authors.lastname: Bigeard
authors.forename: Stephanie
authors.initials: S
authors.lastname: Pateyron
authors.forename: Marie-Ludivine
authors.initials: ML
authors.lastname: de Tauzia-Moreau
authors.forename: Alexandre
authors.initials: A
authors.lastname: Evrard
authors.forename: Axel
authors.initials: A
authors.lastname: Mithöfer
authors.forename: Marie Laure
authors.initials: ML
authors.lastname: Martin-Magniette
authors.forename: Isabelle
authors.initials: I
authors.lastname: Virlogeux-Payant
authors.forename: Heribert
authors.initials: H
authors.lastname: Hirt
mesh_terms: D017360:Arabidopsis / Q000276:immunology* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D005408:Flagellin / Q000378:metabolism*; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism*; D019779:Salmonella enterica / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D005408:Flagellin; D011494:Protein Kinases; C411853:FLS2 protein, Arabidopsis
keywords: Arabidopsis thaliana; FLS2; Salmonella enterica; flagellin; immunity.