title: Riboflavin-induced priming for pathogen defense in Arabidopsis thaliana.
abstract: Riboflavin (vitamin B(2)) participates in a variety of redox processes that affect plant defense responses. Previously we have shown that riboflavin induces pathogen resistance in the absence of hypersensitive cell death (HCD) in plants. Herein, we report that riboflavin induces priming of defense responses in Arabidopsis thaliana toward infection by virulent Pseudomonas syringae pv. tomato DC3000 (Pst). Induced resistance was mechanistically connected with the expression of defense response genes and cellular defense events, including H(2)O(2) burst, HCD, and callose deposition in the plant. Riboflavin treatment and inoculation of plants with Pst were neither active but both synergized to induce defense responses. The priming process needed NPR1 (essential regulator of systemic acquired resistance) and maintenance of H(2)O(2) burst but was independent of salicylic acid, jasmonic acid, ethylene, and abscisic acid. Our results suggest that the role of riboflavin in priming defenses is subject to a signaling process distinct from the known pathways of hormone signal transduction.
authors.affiliation: Plant Growth and Defense Signaling Laboratory, Group of Key Laboratory of Monitoring and Management of Plant Pathogens and Insect Pests, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Shujian
authors.initials: S
authors.lastname: Zhang
authors.forename: Xue
authors.initials: X
authors.lastname: Yang
authors.forename: Maowu
authors.initials: M
authors.lastname: Sun
authors.forename: Feng
authors.initials: F
authors.lastname: Sun
authors.forename: Sheng
authors.initials: S
authors.lastname: Deng
authors.forename: Hansong
authors.initials: H
authors.lastname: Dong
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D054884:Host-Pathogen Interactions; D006861:Hydrogen Peroxide / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology; D010937:Plant Growth Regulators / Q000378:metabolism; D044224:Pseudomonas syringae / Q000276:immunology*; D012256:Riboflavin / Q000494:pharmacology*; D015398:Signal Transduction; D014803:Vitamin B Complex / Q000494:pharmacology*
chemical_list: D029681:Arabidopsis Proteins; C105496:NPR1 protein, Arabidopsis; D010937:Plant Growth Regulators; D014803:Vitamin B Complex; D000040:Abscisic Acid; D006861:Hydrogen Peroxide; D002374:Catalase; D012256:Riboflavin