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. 1992 Feb;11(2):473–477. doi: 10.1002/j.1460-2075.1992.tb05077.x

A viral gene confers hypovirulence-associated traits to the chestnut blight fungus.

G H Choi 1, D L Nuss 1
PMCID: PMC556477  PMID: 1537330

Abstract

A viral double-stranded (ds)RNA associated with reduced virulence (hypovirulence) and the accompanying biological control of the chestnut blight fungus, Cryphonectria parasitica, was shown recently to contain two contiguous coding domains designated ORF A and ORF B. We report here that transformation of an isogenic virulent, dsRNA-free C. parasitica strain with a cDNA copy of ORF A conferred traits similar to those exhibited by the dsRNA-containing hypovirulent strain: characteristics included reduced pigmentation, reduced laccase accumulation and suppressed conidiation. However virulence was not reduced, indicating an apparent uncoupling of associated traits from hypovirulence. These results establish a direct cause and effect relationship between a viral dsRNA genetic element present in a hypovirulent C. parasitica strain and specific phenotypic traits. They demonstrate further that these traits are not the result of a general reaction of the fungus to the presence of the replicating viral RNA, but are caused by a specific viral coding domain.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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