Options
Dissecting the ß-Aminobutyric Acid–Induced Priming Phenomenon in Arabidopsis
Auteur(s)
Ton, Jurriaan
Jakab, Gabor
Toquin, Valérie
Iavicoli, Annalisa
Maeder, Muriel N.
Métraux, Jean-Pierre
Date de parution
2005
In
The Plant Cell, American Society of Plant Biologists, 2005/17/3/987-999
Résumé
Plants treated with the nonprotein amino acid ß-aminobutyric acid (BABA) develop an enhanced capacity to resist biotic and abiotic stresses. This BABA-induced resistance (BABA-IR) is associated with an augmented capacity to express basal defense responses, a phenomenon known as priming. Based on the observation that high amounts of BABA induce sterility in <i>Arabidopsis thaliana</i>, a mutagenesis screen was performed to select mutants impaired in BABA-induced sterility (<i>ibs</i>). Here, we report the isolation and subsequent characterization of three T-DNA–tagged <i>ibs</i> mutants. Mutant <i>ibs1</i> is affected in a cyclin-dependent kinase–like protein, and <i>ibs2</i> is defective in AtSAC1b encoding a polyphosphoinositide phosphatase. Mutant <i>ibs3</i> is affected in the regulation of the <i>ABA1</i> gene encoding the abscisic acid (ABA) biosynthetic enzyme zeaxanthin epoxidase. To elucidate the function of the three <i>IBS</i> genes in plant resistance, the mutants were tested for BABA-IR against the bacterium <i>Pseudomonas syringae</i> pv <i>tomato</i>, the oomycete <i>Hyaloperonospora parasitica</i>, and BABA-induced tolerance to salt. All three <i>ibs</i> mutants were compromised in BABA-IR against <i>H. parasitica</i>, although to a different extent. Whereas <i>ibs1</i> was reduced in priming for salicylate (SA)-dependent trailing necrosis, mutants <i>ibs2</i> and <i>ibs3</i> were affected in the priming for callose deposition. Only <i>ibs1</i> failed to express BABA-IR against P. syringae, which coincided with a defect in priming for SA-inducible <i>PR-1</i> gene expression. By contrast, <i>ibs2</i> and <i>ibs3</i> showed reduced BABA-induced tolerance to salt, which correlated with an affected priming for ABA-inducible gene expression. For all three <i>ibs</i> alleles, the defects in BABA-induced sterility and BABA-induced protection against <i>P. syringae</i>, <i>H. parasitica</i>, and salt could be confirmed in independent mutants. The data presented here introduce three novel regulatory genes involved in priming for different defense responses.
Identifiants
Type de publication
journal article
Dossier(s) à télécharger
