Ulvan, a sulfated polysaccharide from green algae, activates plant immunity through the jasmonic acid signaling pathway

J Biomed Biotechnol. 2010;2010:525291. doi: 10.1155/2010/525291. Epub 2010 Apr 28.


The industrial use of elicitors as alternative tools for disease control needs the identification of abundant sources of them. We report on an elicitor obtained from the green algae Ulva spp. A fraction containing most exclusively the sulfated polysaccharide known as ulvan-induced expression of a GUS gene placed under the control of a lipoxygenase gene promoter. Gene expression profiling was performed upon ulvan treatments on Medicago truncatula and compared to phytohormone effects. Ulvan induced a gene expression signature similar to that observed upon methyl jasmonate treatment (MeJA). Involvement of jasmonic acid (JA) in ulvan response was confirmed by detecting induction of protease inhibitory activity and by hormonal profiling of JA, salicylic acid (SA) and abscisic acid (ABA). Ulvan activity on the hormonal pathway was further consolidated by using Arabidopsis hormonal mutants. Altogether, our results demonstrate that green algae are a potential reservoir of ulvan elicitor which acts through the JA pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetates / immunology
  • Acetates / metabolism*
  • Analysis of Variance
  • Arabidopsis / drug effects
  • Arabidopsis / immunology*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / metabolism
  • Chromatography, Gel
  • Cyclopentanes / immunology
  • Cyclopentanes / metabolism*
  • Gene Expression / drug effects
  • Glucuronidase / metabolism
  • Medicago truncatula / drug effects
  • Medicago truncatula / immunology*
  • Medicago truncatula / metabolism
  • Nucleotidyltransferases / metabolism
  • Oligonucleotide Array Sequence Analysis
  • Oxylipins / immunology
  • Oxylipins / metabolism*
  • Plant Growth Regulators / metabolism
  • Polysaccharides / isolation & purification
  • Polysaccharides / pharmacology*
  • Signal Transduction / drug effects
  • Spectroscopy, Fourier Transform Infrared
  • Ulva / chemistry*


  • Acetates
  • Arabidopsis Proteins
  • Cyclopentanes
  • Oxylipins
  • Plant Growth Regulators
  • Polysaccharides
  • methyl jasmonate
  • JAR1 protein, Arabidopsis
  • Nucleotidyltransferases
  • Glucuronidase