Botrytis cinerea virulence is drastically reduced after disruption of chitin synthase class III gene (Bcchs3a).
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.
Soulié
Marie-Christine
MC
Interactions plantes-pathogènes, UMR 217 INRA/INA-PG/UPMC, 16 rue Claude Bernard, 75005 Paris, France. soulie@ccr.jussieu.fr
Perino
Claude
C
Piffeteau
Annie
A
Choquer
Mathias
M
Malfatti
Pierrette
P
Cimerman
Agnès
A
Kunz
Caroline
C
Boccara
Martine
M
Vidal-Cros
Anne
A
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
D004271:DNA, Fungal; D005656:Fungal Proteins; D002687:Chitin Synthase