title: Activation of R-mediated innate immunity and disease susceptibility is affected by mutations in a cytosolic O-acetylserine (thiol) lyase in Arabidopsis.
abstract: O-acetylserine (thiol) lyases (OASTLs) are evolutionarily conserved proteins among many prokaryotes and eukaryotes that perform sulfur acquisition and synthesis of cysteine. A mutation in the cytosolic OASTL-A1 protein ONSET OF LEAF DEATH3 (OLD3) was previously shown to reduce the OASTL activity of the old3-1 protein in vitro and cause auto-necrosis in specific Arabidopsis accessions. Here we investigated why a mutation in this protein causes auto-necrosis in some but not other accessions. The auto-necrosis was found to depend on Recognition of Peronospora Parasitica 1 (RPP1)-like disease resistance R gene(s) from an evolutionarily divergent R gene cluster that is present in Ler-0 but not the reference accession Col-0. RPP1-like gene(s) show a negative epistatic interaction with the old3-1 mutation that is not linked to reduced cysteine biosynthesis. Metabolic profiling and transcriptional analysis further indicate that an effector triggered-like immune response and metabolic disorder are associated with auto-necrosis in old3-1 mutants, probably activated by an RPP1-like gene. However, the old3-1 protein in itself results in largely neutral changes in primary plant metabolism, stress defence and immune responses. Finally, we showed that lack of a functional OASTL-A1 results in enhanced disease susceptibility against infection with virulent and non-virulent Pseudomonas syringae pv. tomato DC3000 strains. These results reveal an interaction between the cytosolic OASTL and components of plant immunity.
authors.affiliation: Institute of Molecular BioSciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
authors.forename: Jibran
authors.initials: J
authors.lastname: Tahir
authors.affiliation: Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, Am Muehlenberg 1, Potsdam-Golm, 14476, Germany.
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Centre for Bioenergy Plants Research and Development, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China, and.
authors.forename: Hai-Chun
authors.initials: HC
authors.lastname: Jing
authors.affiliation: The New Zealand Institute for Plant & Food Research Limited, Private Bag 11600, Palmerston North, 4442, New Zealand.
authors.forename: Donald A
authors.initials: DA
authors.lastname: Hunter
authors.affiliation: Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, Am Muehlenberg 1, Potsdam-Golm, 14476, Germany.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Tohge
authors.affiliation: Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, Am Muehlenberg 1, Potsdam-Golm, 14476, Germany.
authors.forename: Adriano
authors.initials: A
authors.lastname: Nunes-Nesi
authors.affiliation: Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, Am Muehlenberg 1, Potsdam-Golm, 14476, Germany.
authors.forename: Yariv
authors.initials: Y
authors.lastname: Brotman
authors.affiliation: Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, Am Muehlenberg 1, Potsdam-Golm, 14476, Germany.
authors.forename: Alisdair R
authors.initials: AR
authors.lastname: Fernie
authors.affiliation: Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Wissenschaftspark Golm, Am Muehlenberg 1, Potsdam-Golm, 14476, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Hoefgen
authors.affiliation: Institute of Molecular BioSciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
authors.forename: Paul P
authors.initials: PP
authors.lastname: Dijkwel
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D019757:Carbon-Oxygen Lyases / Q000502:physiology*; D016923:Cell Death / Q000502:physiology; D017343:Genes, Plant / Q000235:genetics / Q000502:physiology; D009154:Mutation / Q000235:genetics; D010935:Plant Diseases / Q000276:immunology*; D057865:Plant Immunity / Q000235:genetics / Q000502:physiology*; D044224:Pseudomonas syringae; D013312:Stress, Physiological / Q000235:genetics / Q000502:physiology
chemical_list: C018725:O-acetylhomoserine (thiol)-lyase; D019757:Carbon-Oxygen Lyases