Open AccessDisruption of the Bcchs3a Chitin Synthase Gene in Botrytis cinerea Is Responsible for Altered Adhesion and Overstimulation of Host Plant Immunity
Author(s) -
Delphine Arbelet,
Pierrette Malfatti,
Elizabeth SimondCôte,
Thierry Fontaine,
Loïc Desquilbet,
Dominique Expert,
Caroline Kunz,
Marie-Christine Soulié
Publication year - 2010
Publication title -
molecular plant-microbe interactions
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.565
H-Index - 153
eISSN - 1943-7706
pISSN - 0894-0282
DOI - 10.1094/mpmi-02-10-0046
Subject(s) - virulence , biology , mutant , botrytis cinerea , phytoalexin , microbiology and biotechnology , arabidopsis thaliana , cell wall , botrytis , chitin , mycelium , chitin synthase , gene , botany , biochemistry , chitosan , resveratrol
The fungal cell wall is a dynamic structure that protects the cell from different environmental stresses suggesting that wall synthesizing enzymes are of great importance for fungal virulence. Previously, we reported the isolation and characterization of a mutant in class III chitin synthase, Bcchs3a, in the phytopathogenic fungus Botrytis cinerea. We demonstrated that virulence of this mutant is severely impaired. Here, we describe the virulence phenotype of the cell-wall mutant Bcchs3a on the model plant Arabidopsis thaliana and analyze its virulence properties, using a variety of A. thaliana mutants. We found that mutant Bcchs3a is virulent on pad2 and pad3 mutant leaves defective in camalexin. Mutant Bcchs3a was not more susceptible towards camalexin than the wild-type strain but induced phytoalexin accumulation at the infection site on Col-0 plants. Moreover, this increase in camalexin was correlated with overexpression of the PAD3 gene observed as early as 18 h postinoculation. The infection process of the mutant mycelium was always delayed by 48 h, even on pad3 plants, probably because of lack of mycelium adhesion. No loss in virulence was found when Bcchs3a conidia were used as the inoculum source. Collectively, these data led us to assign a critical role to the BcCHS3a chitin synthase isoform, both in fungal virulence and plant defense response.