1. Molecular Characterization of Vegetative Incompatibility Genes That Restrict Hypovirus Transmission in the Chestnut Blight Fungus Cryphonectria parasitica
- Author
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Gil H. Choi, Myron L. Smith, Michael G. Milgroom, Donald L. Nuss, Angus L. Dawe, and Alexander Churbanov
- Subjects
Genotype ,Genotyping Techniques ,Molecular Sequence Data ,Locus (genetics) ,Investigations ,Models, Biological ,Fungal Proteins ,03 medical and health sciences ,Ascomycota ,Cellular Genetics ,Chestnut blight ,Genetics ,Hypovirus ,Cryphonectria ,Alleles ,030304 developmental biology ,Heterokaryon ,Comparative genomics ,0303 health sciences ,Fungal protein ,Polymorphism, Genetic ,biology ,030306 microbiology ,fungi ,Epistasis, Genetic ,biology.organism_classification ,Genetic Loci ,Mutation ,Mycovirus - Abstract
Genetic nonself recognition systems such as vegetative incompatibility operate in many filamentous fungi to regulate hyphal fusion between genetically dissimilar individuals and to restrict the spread of virulence-attenuating mycoviruses that have potential for biological control of pathogenic fungi. We report here the use of a comparative genomics approach to identify seven candidate polymorphic genes associated with four vegetative incompatibility (vic) loci of the chestnut blight fungus Cryphonectria parasitica. Disruption of candidate alleles in one of two strains that were heteroallelic at vic2, vic6, or vic7 resulted in enhanced virus transmission, but did not prevent barrage formation associated with mycelial incompatibility. Detailed characterization of the vic6 locus revealed the involvement of nonallelic interactions between two tightly linked genes in barrage formation, heterokaryon formation, and asymmetric, gene-specific influences on virus transmission. The combined results establish molecular identities of genes associated with four C. parasitica vic loci and provide insights into how these recognition factors interact to trigger incompatibility and restrict virus transmission.
- Published
- 2012