title: HopAS1 recognition significantly contributes to Arabidopsis nonhost resistance to Pseudomonas syringae pathogens.
abstract: • Plant immunity is activated by sensing either conserved microbial signatures, called pathogen/microbe-associated molecular patterns (P/MAMPs), or specific effectors secreted by pathogens. However, it is not known why most microbes are nonpathogenic in most plant species. • Nonhost resistance (NHR) consists of multiple layers of innate immunity and protects plants from the vast majority of potentially pathogenic microbes. Effector-triggered immunity (ETI) has been implicated in race-specific disease resistance. However, the role of ETI in NHR is unclear. • Pseudomonas syringae pv. tomato (Pto) T1 is pathogenic in tomato (Solanum lycopersicum) yet nonpathogenic in Arabidopsis. Here, we show that, in addition to the type III secretion system (T3SS)-dependent effector (T3SE) avrRpt2, a second T3SE of Pto T1, hopAS1, triggers ETI in nonhost Arabidopsis. • hopAS1 is broadly present in P. syringae strains, contributes to virulence in tomato, and is quantitatively required for Arabidopsis NHR to Pto T1. Strikingly, all tested P. syringae strains that are pathogenic in Arabidopsis carry truncated hopAS1 variants of forms, demonstrating that HopAS1-triggered immunity plays an important role in Arabidopsis NHR to a broad-range of P. syringae strains.
authors: The Sainsbury Laboratory, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
authors: Kee Hoon
authors: KH
authors: Sohn
authors: The Sainsbury Laboratory, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
authors: Simon B
authors: SB
authors: Saucet
authors: Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Latham Hall, Blacksburg VA 24061, USA.
authors: Christopher R
authors: CR
authors: Clarke
authors: Department of Plant Pathology, Physiology and Weed Science, Virginia Tech, Latham Hall, Blacksburg VA 24061, USA.
authors: Boris A
authors: BA
authors: Vinatzer
authors: Centre for the Analysis of Genome Evolution and Function, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada.
authors: Heath E
authors: HE
authors: O'Brien
authors: Centre for the Analysis of Genome Evolution and Function, University of Toronto, 25 Willcocks Street, Toronto, Ontario M5S 3B2, Canada.
authors: David S
authors: DS
authors: Guttman
authors: The Sainsbury Laboratory, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK.
authors: Jonathan D G
authors: JDG
authors: Jones
mesh_terms: D000483:Alleles; D017360:Arabidopsis / Q000276:immunology* / Q000382:microbiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D060467:Disease Resistance / Q000276:immunology*; D054884:Host-Pathogen Interactions / Q000276:immunology*; D018551:Solanum lycopersicum / Q000382:microbiology; D009154:Mutation / Q000235:genetics; D057865:Plant Immunity / Q000276:immunology; D044224:Pseudomonas syringae / Q000276:immunology* / Q000472:pathogenicity; D014774:Virulence / Q000276:immunology
chemical_list: D001426:Bacterial Proteins