title: Engineering super mycovirus donor strains of chestnut blight fungus by systematic disruption of multilocus vic genes.
abstract: Transmission of mycoviruses that attenuate virulence (hypovirulence) of pathogenic fungi is restricted by allorecognition systems operating in their fungal hosts. We report the use of systematic molecular gene disruption and classical genetics for engineering fungal hosts with superior virus transmission capabilities. Four of five diallelic virus-restricting allorecognition [vegetative incompatibility (vic)] loci were disrupted in the chestnut blight fungus Cryphonectria parasitica using an adapted Cre-loxP recombination system that allowed excision and recycling of selectable marker genes (SMGs). SMG-free, quadruple vic mutant strains representing both allelic backgrounds of the remaining vic locus were then produced through mating. In combination, these super donor strains were able to transmit hypoviruses to strains that were heteroallelic at one or all of the virus-restricting vic loci. These results demonstrate the feasibility of modulating allorecognition to engineer pathogenic fungi for more efficient transmission of virulence-attenuating mycoviruses and enhanced biological control potential.
authors: Institute for Bioscience and Biotechnology Research and Department of Cell Biology and Molecular Genetics, University of Maryland, Rockville, MD 20850.
authors: Dong-Xiu
authors: DX
authors: Zhang
authors: Institute for Bioscience and Biotechnology Research and Department of Cell Biology and Molecular Genetics, University of Maryland, Rockville, MD 20850 dnuss@umd.edu.
authors: Donald L
authors: DL
authors: Nuss
mesh_terms: D031319:Aesculus / Q000382:microbiology; D000067148:Fungal Viruses / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity; D005818:Genetic Engineering; D056426:Genetic Loci; D010935:Plant Diseases / Q000382:microbiology; D020037:Sordariales / Q000235:genetics / Q000378:metabolism / Q000821:virology
keywords: Cryphonectria parasitica; hypovirulence; mycovirus transmission; non-self recognition; vegetative incompatibility