Virus-associated down-regulation of the gene encoding cryparin, an abundant cell-surface protein from the chestnut blight fungus, Cryphonectria parasitica.

We report here the cloning and analysis of the gene (Crp) encoding cryparin (CRP) and the suppression of the accumulation of its mRNA by a double-stranded RNA virus. CRP belongs to a group of fungal hydrophobic cell surface proteins and has sequence similarity to cerato-ulmin, a phytotoxin produced by Ophiostoma ulmi, the Dutch elm disease pathogen. Transcripts of the Crp gene represent almost 25% of the mRNA of the fungal cell during the peak of CRP production.