title: Allelic variation in two distinct Pseudomonas syringae flagellin epitopes modulates the strength of plant immune responses but not bacterial motility.
abstract: The bacterial flagellin (FliC) epitopes flg22 and flgII-28 are microbe-associated molecular patterns (MAMPs). Although flg22 is recognized by many plant species via the pattern recognition receptor FLS2, neither the flgII-28 receptor nor the extent of flgII-28 recognition by different plant families is known. Here, we tested the significance of flgII-28 as a MAMP and the importance of allelic diversity in flg22 and flgII-28 in plant-pathogen interactions using purified peptides and a Pseudomonas syringae ∆fliC mutant complemented with different fliC alleles. The plant genotype and allelic diversity in flg22 and flgII-28 were found to significantly affect the plant immune response, but not bacterial motility. The recognition of flgII-28 is restricted to a number of solanaceous species. Although the flgII-28 peptide does not trigger any immune response in Arabidopsis, mutations in both flg22 and flgII-28 have FLS2-dependent effects on virulence. However, the expression of a tomato allele of FLS2 does not confer to Nicotiana benthamiana the ability to detect flgII-28, and tomato plants silenced for FLS2 are not altered in flgII-28 recognition. Therefore, MAMP diversification is an effective pathogen virulence strategy, and flgII-28 appears to be perceived by an as yet unidentified receptor in the Solanaceae, although it has an FLS2-dependent virulence effect in Arabidopsis.
authors.affiliation: Department of Plant Pathology, Physiology and Weed Sciences, Latham Hall, Ag Quad Lane, Virginia Tech, Blacksburg, VA, 24061, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Clarke
authors.affiliation: Zurich-Basel Plant Science Center, Department of Environmental Sciences, University of Basel, Hebelstrasse 1, 4056, Basel, Switzerland.
authors.forename: Delphine
authors.initials: D
authors.lastname: Chinchilla
authors.affiliation: Boyce Thompson Institute for Plant Research, Ithaca, NY, 14853, USA.
authors.forename: Sarah R
authors.initials: SR
authors.lastname: Hind
authors.affiliation: Graduate School of Natural Science and Technology, Okayama University, Tsushima-naka 1-1-1, Okayama, 700-8530, Japan.
authors.forename: Fumiko
authors.initials: F
authors.lastname: Taguchi
authors.affiliation: Graduate School of Natural Science and Technology, Okayama University, Tsushima-naka 1-1-1, Okayama, 700-8530, Japan.
authors.forename: Ryuji
authors.initials: R
authors.lastname: Miki
authors.affiliation: Graduate School of Natural Science and Technology, Okayama University, Tsushima-naka 1-1-1, Okayama, 700-8530, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Ichinose
authors.affiliation: Boyce Thompson Institute for Plant Research, Ithaca, NY, 14853, USA.|Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY, 14853, USA.|Genomics and Biotechnology Section, Department of Biological Sciences, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Martin
authors.affiliation: Department of Statistics, Virginia Tech, Blacksburg, VA, 24061, USA.
authors.forename: Scotland
authors.initials: S
authors.lastname: Leman
authors.affiliation: Zentrum für Molekularbiologie der Pflanzen, University Tübingen, Tübingen, 72076, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Felix
authors.affiliation: Department of Plant Pathology, Physiology and Weed Sciences, Latham Hall, Ag Quad Lane, Virginia Tech, Blacksburg, VA, 24061, USA.
authors.forename: Boris A
authors.initials: BA
authors.lastname: Vinatzer
mesh_terms: D000483:Alleles; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D005408:Flagellin / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D054884:Host-Pathogen Interactions / Q000235:genetics; D018551:Solanum lycopersicum / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D009154:Mutation; D010935:Plant Diseases / Q000235:genetics; D057865:Plant Immunity / Q000235:genetics*; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D044224:Pseudomonas syringae / Q000235:genetics / Q000472:pathogenicity* / Q000502:physiology; D019657:Solanaceae / Q000235:genetics / Q000378:metabolism / Q000382:microbiology*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism / Q000382:microbiology
chemical_list: D029681:Arabidopsis Proteins; D005408:Flagellin; D011494:Protein Kinases; C411853:FLS2 protein, Arabidopsis
keywords: FLS2; flagellin; flg22; flgII-28; microbe-associated molecular pattern (MAMP); pathogen-associated molecular pattern (PAMP); pattern-triggered immunity (PTI)