title: Peroxidase-dependent apoplastic oxidative burst in Arabidopsis required for pathogen resistance.
abstract: The oxidative burst is an early response to pathogen attack leading to the production of reactive oxygen species (ROS) including hydrogen peroxide. Two major mechanisms involving either NADPH oxidases or peroxidases that may exist singly or in combination in different plant species have been proposed for the generation of ROS. We identified an Arabidopsis thaliana azide-sensitive but diphenylene iodonium-insensitive apoplastic oxidative burst that generates H(2)O(2) in response to a Fusarium oxysporum cell-wall preparation. Transgenic Arabidopsis plants expressing an anti-sense cDNA encoding a type III peroxidase, French bean peroxidase type 1 (FBP1) exhibited an impaired oxidative burst and were more susceptible than wild-type plants to both fungal and bacterial pathogens. Transcriptional profiling and RT-PCR analysis showed that the anti-sense (FBP1) transgenic plants had reduced levels of specific peroxidase-encoding mRNAs, including mRNAs corresponding to Arabidopsis genes At3g49120 (AtPCb) and At3g49110 (AtPCa) that encode two class III peroxidases with a high degree of homology to FBP1. These data indicate that peroxidases play a significant role in generating H(2)O(2) during the Arabidopsis defense response and in conferring resistance to a wide range of pathogens.
authors.affiliation: School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK.
authors.forename: Laurence V
authors.initials: LV
authors.lastname: Bindschedler
authors.forename: Julia
authors.initials: J
authors.lastname: Dewdney
authors.forename: Kris A
authors.initials: KA
authors.lastname: Blee
authors.forename: Julie M
authors.initials: JM
authors.lastname: Stone
authors.forename: Tsuneaki
authors.initials: T
authors.lastname: Asai
authors.forename: Julia
authors.initials: J
authors.lastname: Plotnikov
authors.forename: Carine
authors.initials: C
authors.lastname: Denoux
authors.forename: Tezni
authors.initials: T
authors.lastname: Hayes
authors.forename: Chris
authors.initials: C
authors.lastname: Gerrish
authors.forename: Dewi R
authors.initials: DR
authors.lastname: Davies
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Ausubel
authors.forename: G Paul
authors.initials: GP
authors.lastname: Bolwell
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000382:microbiology / Q000502:physiology*; D037341:Fumonisins / Q000378:metabolism; D005658:Fungi / Q000472:pathogenicity*; D020869:Gene Expression Profiling; D010544:Peroxidases / Q000378:metabolism*; D030821:Plants, Genetically Modified; D017382:Reactive Oxygen Species; D016897:Respiratory Burst; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D037341:Fumonisins; D017382:Reactive Oxygen Species; C056933:fumonisin B1; D010544:Peroxidases