A circular single-stranded dna mycovirus infects plants and confers broad-spectrum resistance against fungal diseases
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Published version
Author(s)
Type
Journal Article
Abstract
Circular single-stranded (ss) DNA viruses have been rarely found in fungi, and the evolutionary and ecological relationships among ssDNA viruses infecting fungi and other organisms remain unclear. Here, a novel circular ssDNA virus, tentatively named Diaporthe sojae circular DNA virus 1 (DsCDV1), was identified in the phytopathogenic fungus Diaporthe sojae isolated from pear trees. DsCDV1 has a monopartite genome (3,185 nt in size) encapsidated in isometric virions (21-26 nm in diameter). The genome comprises seven putative open reading frames encoding a discrete replicase (Rep) split by an intergenic region, a putative capsid protein (CP), several proteins of unknown function (P1 to P4), and a long intergenic region. Notably, the two split parts of DsCDV1 Rep share high identities with the Reps of Geminiviridae and Genomoviridae, respectively, indicating an evolutionary linkage with both families. Phylogenetic analysis based on Rep or CP sequences placed DsCDV1 in a unique cluster, supporting the establishment of a new family, tentatively named Gegemycoviridae, intermediate to both families. DsCDV1 significantly attenuates fungal growth and nearly erases virulence when transfected into the host fungus. Remarkably, DsCDV1 can systematically infect tobacco and pear seedlings, providing broad-spectrum resistance to fungal diseases. Subcellular localization analysis revealed that P3 systematically localizes in plasmodesmata, while and its expression in trans-complementation experiments restores the wild-type phenotype of a movement-deficient plant virus; thus P3 is identified as a movement protein. DsCDV1 exhibits unique molecular and biological traits not observed in other ssDNA viruses, serving as a link between fungal and plant ssDNA viruses and presenting an evolutionary connection between ssDNA viruses and fungi. These findings contribute to expanding our understanding of ssDNA virus diversity and evolution, offering potential biocontrol applications for managing crucial plant diseases.
Date Issued
2024-06-03
Date Acceptance
2024-05-09
ISSN
1674-2052
Publisher
Elsevier
Start Page
955
End Page
971
Journal / Book Title
Molecular Plant
Volume
17
Copyright Statement
© 2024 The Author.
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Identifier
https://www.sciencedirect.com/science/article/pii/S1674205224001515?via%3Dihub
https://www.ncbi.nlm.nih.gov/pubmed/38745413
Publication Status
Published
Coverage Spatial
England
Date Publish Online
2024-05-13