title: Exogenous proteinogenic amino acids induce systemic resistance in rice.
abstract: BACKGROUND
  Plant immune responses can be induced by endogenous and exogenous signaling molecules. Recently, amino acids and their metabolites have been reported to affect the plant immune system. However, how amino acids act in plant defense responses has yet to be clarified. Here, we report that treatment of rice roots with amino acids such as glutamate (Glu) induced systemic disease resistance against rice blast in leaves.
  
  
  RESULTS
  Treatment of roots with Glu activated the transcription of a large variety of defense-related genes both in roots and leaves. In leaves, salicylic acid (SA)-responsive genes, rather than jasmonic acid (JA) or ethylene (ET)-responsive genes, were induced by this treatment. The Glu-induced blast resistance was partially impaired in rice plants deficient in SA signaling such as NahG plants expressing an SA hydroxylase, WRKY45-knockdown, and OsNPR1-knockdown plants. The JA-deficient mutant cpm2 exhibited full Glu-induced blast resistance.
  
  
  CONCLUSIONS
  Our results indicate that the amino acid-induced blast resistance partly depends on the SA pathway but an unknown SA-independent signaling pathway is also involved.
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki, 210-8681, Japan. naoki_kadotani@ajinomoto.com.
authors.forename: Naoki
authors.initials: N
authors.lastname: Kadotani
authors.affiliation: Plant Disease Resistance Research Unit, Division of Plant Science, National Institute of Agrobiological Sciences, 2-1-2, Kannondai, Tsukuba, 305-8602, Japan. aya.akagi@bayer.com.|Bayer Crop Science, Tokyo, 100-8262, Japan. aya.akagi@bayer.com.
authors.forename: Aya
authors.initials: A
authors.lastname: Akagi
authors.affiliation: Plant Disease Resistance Research Unit, Division of Plant Science, National Institute of Agrobiological Sciences, 2-1-2, Kannondai, Tsukuba, 305-8602, Japan. takatsuh@affrc.go.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Takatsuji
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki, 210-8681, Japan. tetsuya_miwa@ajinomoto.com.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Miwa
authors.affiliation: Institute for Innovation, Ajinomoto Co., Inc, 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki, 210-8681, Japan. daisuke_igarashi@ajinomoto.com.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Igarashi
mesh_terms: D000596:Amino Acids / Q000276:immunology*; D020869:Gene Expression Profiling; D017343:Genes, Plant; D018698:Glutamic Acid / Q000276:immunology / Q000378:metabolism; D020082:Magnaporthe / Q000276:immunology; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D012275:Oryza / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D018517:Plant Roots / Q000276:immunology; D015398:Signal Transduction
chemical_list: D000596:Amino Acids; D018698:Glutamic Acid; D019158:N-Acetylneuraminic Acid