Blog
About

  • Record: found
  • Abstract: found
  • Article: not found

Two pathways act in an additive rather than obligatorily synergistic fashion to induce systemic acquired resistance and PR gene expression

1 , , 1

BMC Plant Biology

BioMed Central

Read this article at

ScienceOpenPublisherPMC
Bookmark
      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

      Abstract

      BackgroundLocal infection with necrotizing pathogens induces whole plant immunity to secondary challenge. Pathogenesis-related genes are induced in parallel with this systemic acquired resistance response and thought to be co-regulated. The hypothesis of co-regulation has been challenged by induction of Arabidopsis PR-1 but not systemic acquired resistance in npr1 mutant plants responding to Pseudomonas syringae carrying the avirulence gene avrRpt2. However, experiments with ndr1 mutant plants have revealed major differences between avirulence genes. The ndr1-1 mutation prevents hypersensitive cell death, systemic acquired resistance and PR-1 induction elicited by bacteria carrying avrRpt2. This mutation does not prevent these responses to bacteria carrying avrB.ResultsSystemic acquired resistance, PR-1 induction and PR-5 induction were assessed in comparisons of npr1-2 and ndr1-1 mutant plants, double mutant plants, and wild-type plants. Systemic acquired resistance was displayed by all four plant lines in response to Pseudomonas syringae bacteria carrying avrB. PR-1 induction was partially impaired by either single mutation in response to either bacterial strain, but only fully impaired in the double mutant in response to avrRpt2. PR-5 induction was not fully impaired in any of the mutants in response to either avirulence gene.ConclusionTwo pathways act additively, rather than in an obligatorily synergistic fashion, to induce systemic acquired resistance, PR-1 and PR-5. One of these pathways is NPR1-independent and depends on signals associated with hypersensitive cell death. The other pathway is dependent on salicylic acid accumulation and acts through NPR1. At least two other pathways also contribute additively to PR-5 induction.

      Related collections

      Most cited references 40

      • Record: found
      • Abstract: found
      • Article: not found

      Systems biology: a brief overview.

      To understand biology at the system level, we must examine the structure and dynamics of cellular and organismal function, rather than the characteristics of isolated parts of a cell or organism. Properties of systems, such as robustness, emerge as central issues, and understanding these properties may have an impact on the future of medicine. However, many breakthroughs in experimental devices, advanced software, and analytical methods are required before the achievements of systems biology can live up to their much-touted potential.
        Bookmark
        • Record: found
        • Abstract: found
        • Article: not found

        MAP kinase signalling cascade in Arabidopsis innate immunity.

        There is remarkable conservation in the recognition of pathogen-associated molecular patterns (PAMPs) by innate immune responses of plants, insects and mammals. We developed an Arabidopsis thaliana leaf cell system based on the induction of early-defence gene transcription by flagellin, a highly conserved component of bacterial flagella that functions as a PAMP in plants and mammals. Here we identify a complete plant MAP kinase cascade (MEKK1, MKK4/MKK5 and MPK3/MPK6) and WRKY22/WRKY29 transcription factors that function downstream of the flagellin receptor FLS2, a leucine-rich-repeat (LRR) receptor kinase. Activation of this MAPK cascade confers resistance to both bacterial and fungal pathogens, suggesting that signalling events initiated by diverse pathogens converge into a conserved MAPK cascade.
          Bookmark
          • Record: found
          • Abstract: not found
          • Article: not found

          The families of pathogenesis-related proteins, their activities, and comparative analysis of PR-1 type proteins

            Bookmark

            Author and article information

            Affiliations
            [1 ]Department of Plant and Soil Sciences, Delaware Agricultural Experiment Station, College of Agriculture and Natural Resources, University of Delaware, Newark, DE, USA
            Contributors
            Journal
            BMC Plant Biol
            BMC Plant Biology
            BioMed Central (London )
            1471-2229
            2002
            15 October 2002
            : 2
            : 9
            130961
            1471-2229-2-9
            12381270
            10.1186/1471-2229-2-9
            Copyright © 2002 Zhang and Shapiro; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.
            Categories
            Research Article

            Plant science & Botany

            Comments

            Comment on this article