title: Respiratory burst oxidase homologue A of barley contributes to penetration by the powdery mildew fungus Blumeria graminis f. sp. hordei.
abstract: Reactive oxygen intermediates (ROI) are closely related to defence reactions of plants against pathogens. A prominent role in the production of ROI has been attributed to the plant respiratory burst oxidase homologues (RBOH) of the human phagocyte GP91(phox). A barley RBOH, which encodes a putative superoxide (O2*-)) producing NADPH oxidase, is described here. Histochemical analysis of the barley-Blumeria graminis f. sp. hordei (Bgh) interaction showed that O(2*-) is produced locally at the site of penetration. In contrast, hydrogen peroxide (H2O2) is produced in non-penetrated cell wall appositions. A barley RBOHA cDNA was isolated and a minor induction of expression of RBOHA was observed during the interactions of barley with Bgh. Transient RNA interference-mediated gene silencing of HvRBOHA during the penetration process of Bgh led to an increase of basal penetration resistance. The results support a potential role of HvRBOHA in cellular accessibility to Blumeria graminis.
authors.affiliation: Research Centre for BioSystems, Land Use and Nutrition, Institute of Phytopathology and Applied Zoology, Justus-Liebig-University of Giessen, Heinrich-Buff Ring 26-32, D-35392 Giessen, Germany.
authors.forename: Marco
authors.initials: M
authors.lastname: Trujillo
authors.forename: Lothar
authors.initials: L
authors.lastname: Altschmied
authors.forename: Patrick
authors.initials: P
authors.lastname: Schweizer
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Kogel
authors.forename: Ralph
authors.initials: R
authors.lastname: Hückelhoven
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D001467:Hordeum / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology; D006861:Hydrogen Peroxide / Q000378:metabolism; D008969:Molecular Sequence Data; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016415:Sequence Alignment; D013481:Superoxides / Q000378:metabolism
chemical_list: D010940:Plant Proteins; D017382:Reactive Oxygen Species; D013481:Superoxides; D006861:Hydrogen Peroxide; D009247:NADH, NADPH Oxidoreductases