Priming of plant innate immunity by rhizobacteria and beta-aminobutyric acid: differences and similarities in regulation

Sjoerd Van der Ent, Marieke Van Hulten, Maria J. Pozo, Tomasz Czechowski, Michael K. Udvardi, Corne M. J. Pieterse, Jurriaan Ton

Research output: Contribution to journalArticlepeer-review

Abstract

P>Pseudomonas fluorescens WCS417r bacteria and beta-aminobutyric acid can induce disease resistance in Arabidopsis, which is based on priming of defence.

In this study, we examined the differences and similarities of WCS417r- and beta-aminobutyric acid-induced priming.

Both WCS417r and beta-aminobutyric acid prime for enhanced deposition of callose-rich papillae after infection by the oomycete Hyaloperonospora arabidopsis. This priming is regulated by convergent pathways, which depend on phosphoinositide- and ABA-dependent signalling components. Conversely, induced resistance by WCS417r and beta-aminobutyric acid against the bacterial pathogen Pseudomonas syringae are controlled by distinct NPR1-dependent signalling pathways. As WCS417r and beta-aminobutyric acid prime jasmonate- and salicylate-inducible genes, respectively, we subsequently investigated the role of transcription factors. A quantitative PCR-based genome-wide screen for putative WCS417r- and beta-aminobutyric acid-responsive transcription factor genes revealed distinct sets of priming-responsive genes. Transcriptional analysis of a selection of these genes showed that they can serve as specific markers for priming. Promoter analysis of WRKY genes identified a putative cis-element that is strongly over-represented in promoters of 21 NPR1-dependent, beta-aminobutyric acid-inducible WRKY genes.

Our study shows that priming of defence is regulated by different pathways, depending on the inducing agent and the challenging pathogen. Furthermore, we demon-strated that priming is associated with the enhanced expression of transcription factors.

New Phytologist (2009) 183: 419-431doi: 10.1111/j.1469-8137.2009.02851.x.

Original languageEnglish
Pages (from-to)419-431
Number of pages13
JournalNew Phytologist
Volume183
Issue number2
DOIs
Publication statusPublished - Jul 2009

Keywords

  • Arabidopsis thaliana
  • callose
  • NPR1
  • priming
  • transcription factors
  • WRKY
  • SYSTEMIC ACQUIRED-RESISTANCE
  • ARABIDOPSIS TRANSCRIPTION FACTOR
  • DISEASE RESISTANCE
  • BIOCONTROL BACTERIA
  • PATHOGEN INFECTION
  • GENE-EXPRESSION
  • SALICYLIC-ACID
  • DOWNY MILDEW
  • DEFENSE
  • PATHWAY

Cite this