Large-scale expressed sequence tag analysis for the chestnut blight fungus Cryphonectria parasitica

Cryphonectria parasitica is the causal fungal agent responsible for the chestnut blight disease. We report the generation of 14,263 expressed sequence tags representing 6318 unisequences for the fungus. Functional annotation of these unisequences revealed different gene expression patterns for wild-type and hypovirus-infected cultures at the sporulation stage and allowed the reconstruction of key C. parasitica signal transduction pathways conserved in the Sorbidaryomycetes. A list of homologous genes implicated in pathogenicity, sporulation, and virus replication in other fungi were also identified. A large-scale gene comparison indicated that C. parasitica is most closely related to the plant pathogen Fusarium graminearum but more closely related to the non-pathogen Neurospora crassa than to the rice pathogen Magnaporthe grisea. This transcriptional information lays a new and solid ground for further investigation of both the biology of the fungus and interaction between a hypovirus and the host fungus.