Riboflavin-induced Priming for Pathogen Defense in Arabidopsis thaliana

• Published in: Journal of integrative plant biology Vol. 51; no. 2; pp. 167 - 174
• Main Authors: Zhang, Shujian, Yang, Xue, Sun, Maowu, Sun, Feng, Deng, Sheng, Dong, Hansong
• Format: Journal Article
• Language: English
• Published: Melbourne, Australia Melbourne, Australia : Blackwell Publishing Asia 01.02.2009; Blackwell Publishing Asia; 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
• Subjects: abscisic acid; Abscisic Acid - metabolism; Arabidopsis; Arabidopsis - drug effects; Arabidopsis - immunology; Arabidopsis - metabolism; Arabidopsis Proteins; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; callose; callose deposition; Catalase; Catalase - metabolism; cell death; defense responses; drug effects; ethylene; Gene Expression Regulation, Plant; genes; Host-Pathogen Interactions; hydrogen peroxide; Hydrogen Peroxide - metabolism; hypersensitive cell death; immunology; jasmonic acid; Lycopersicon esculentum; metabolism; microbiology; pathogens; pharmacology; Plant Diseases; Plant Diseases - immunology; Plant Diseases - microbiology; Plant Growth Regulators; Plant Growth Regulators - metabolism; priming; Pseudomonas syringae; Pseudomonas syringae - immunology; Pseudomonas syringae pv. tomato; riboflavin; Riboflavin - pharmacology; salicylic acid; Signal Transduction; systemic acquired resistance; virulence; Vitamin B Complex; Vitamin B Complex - pharmacology; callose deposition; defense responses; hypersensitive cell death; priming; riboflavin; hydrogen peroxide
• ISSN: 1672-9072; 1744-7909; 1744-7909
• DOI: 10.1111/j.1744-7909.2008.00763.x

Riboflavin (vitamin B₂) 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 H₂O₂ 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 H₂O₂ 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.