title: Five Xanthomonas type III effectors suppress cell death induced by components of immunity-associated MAP kinase cascades.
abstract: Mitogen-activated protein kinase (MAPK) cascades play a fundamental role in signaling of plant immunity and mediate elicitation of cell death. Xanthomonas spp. manipulate plant signaling by using a type III secretion system to deliver effector proteins into host cells. We examined the ability of 33 Xanthomonas effectors to inhibit cell death induced by overexpression of components of MAPK cascades in Nicotiana benthamiana plants. Five effectors inhibited cell death induced by overexpression of MAPKKKα and MEK2, but not of MAP3Kε. In addition, expression of AvrBs1 in yeast suppressed activation of the high osmolarity glycerol MAPK pathway, suggesting that the target of this effector is conserved in eukaryotic organisms. These results indicate that Xanthomonas employs several type III effectors to suppress immunity-associated cell death mediated by MAPK cascades.
authors.affiliation: a Department of Molecular Biology and Ecology of Plants ; Tel-Aviv University ; Tel-Aviv , Israel.
authors.forename: Doron
authors.initials: D
authors.lastname: Teper
authors.affiliation: a Department of Molecular Biology and Ecology of Plants ; Tel-Aviv University ; Tel-Aviv , Israel.
authors.forename: Sukumaran
authors.initials: S
authors.lastname: Sunitha
authors.affiliation: b Boyce Thompson Institute for Plant Research ; Ithaca , NY USA.|c Department of Plant Pathology and Plant-Microbe Biology ; Cornell University ; Ithaca , NY USA.
authors.forename: Gregory B
authors.initials: GB
authors.lastname: Martin
authors.affiliation: a Department of Molecular Biology and Ecology of Plants ; Tel-Aviv University ; Tel-Aviv , Israel.
authors.forename: Guido
authors.initials: G
authors.lastname: Sessa
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D016923:Cell Death; D057131:Immune Evasion; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology; D057865:Plant Immunity; D010940:Plant Proteins / Q000378:metabolism; D015398:Signal Transduction; D014026:Nicotiana / Q000378:metabolism / Q000382:microbiology*; D014974:Xanthomonas / Q000378:metabolism / Q000472:pathogenicity*
chemical_list: D001426:Bacterial Proteins; D010940:Plant Proteins; D020928:Mitogen-Activated Protein Kinases
keywords: MAP kinase; Xanthomonas; cell death; hypersensitive response; plant immunity; type III secreted effectors; yeast