title: Botrytis cinerea virulence is drastically reduced after disruption of chitin synthase class III gene (Bcchs3a).
abstract: Botrytis cinerea is an important phytopathogenic fungus requiring new methods of control. Chitin biosynthesis, which involves seven classes of chitin synthases, could be an attractive target. A fragment encoding one of the class III enzymes was used to disrupt the corresponding Bcchs3a gene in the B. cinerea genome. The resulting mutant exhibited a 39% reduction in its chitin content and an 89% reduction in its in vitro chitin synthase activity, compared with the wild-type strain. Bcchs3a mutant was not affected in its growth in liquid medium, neither in its production of sclerotia, micro- and macroconidia. In contrast, the mutant Bcchs3a was severely impaired in its growth on solid medium. Counterbalancing this defect in radial growth, Bcchs3a mutant presented a large increase in hyphal ramification, resulting in an enhanced aerial growth. Observations by different techniques of microscopy revealed a thick extracellular matrix around the hyphal tips. Moreover, Bcchs3a mutant had a largely reduced virulence on Vitis vinifera and Arabidopsis thaliana leaves.
authors.affiliation: Interactions plantes-pathogènes, UMR 217 INRA/INA-PG/UPMC, 16 rue Claude Bernard, 75005 Paris, France. soulie@ccr.jussieu.fr
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Soulié
authors.forename: Claude
authors.initials: C
authors.lastname: Perino
authors.forename: Annie
authors.initials: A
authors.lastname: Piffeteau
authors.forename: Mathias
authors.initials: M
authors.lastname: Choquer
authors.forename: Pierrette
authors.initials: P
authors.lastname: Malfatti
authors.forename: Agnès
authors.initials: A
authors.lastname: Cimerman
authors.forename: Caroline
authors.initials: C
authors.lastname: Kunz
authors.forename: Martine
authors.initials: M
authors.lastname: Boccara
authors.forename: Anne
authors.initials: A
authors.lastname: Vidal-Cros
mesh_terms: D017360:Arabidopsis / Q000382:microbiology; D001483:Base Sequence; D020171:Botrytis / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity*; D002687:Chitin Synthase / Q000235:genetics* / Q000502:physiology; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics* / Q000502:physiology; D005800:Genes, Fungal; D008854:Microscopy, Electron; D009154:Mutation; D010935:Plant Diseases / Q000382:microbiology; D018515:Plant Leaves / Q000382:microbiology; D014774:Virulence / Q000235:genetics / Q000502:physiology; D027843:Vitis / Q000382:microbiology
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D002687:Chitin Synthase