A circular single-stranded DNA mycovirus infects plants and confers broad-spectrum fungal resistance  

作　　者：Xianhong Wang Ioly Kotta-Loizou Robert H.A.Coutts Huifang Deng Zhenhao Han Ni Hong Karim Shafik Liping Wang Yashuang Guo Mengmeng Yang Wenxing Xu Guoping Wang 

机构地区：[1]National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops,Wuhan 430070,China [2]Hubei Hongshan Laboratory,Wuhan 430070,China [3]College of Plant Science and Technology,Huazhong Agricultural University,Wuhan 430070,China [4]Key Lab of Plant Pathology of Hubei Province,Wuhan 430070,China [5]Department of Life Sciences,Faculty of Natural Sciences,Imperial College London,London SW72AZ,UK [6]Department of Clinical,Pharmaceutical and Biological Science,School of Life and Medical Sciences,University of Hertfordshire,Hatfield AL109AB,UK [7]Department of Plant Pathology,Faculty of Agriculture,Alexandria University,Alexandria 21526,Egypt

出　　处：《Molecular Plant》2024年第6期955-971,共17页分子植物（英文版）

基　　金：supported by Earmarked Fund for China Agricultural Research System(grant number CARS-28)to G.W.and W.X.;the National Natural Science Foundation of China(grant number 32172475)to W.X.

摘　　要：Circular single-stranded DNA(ssDNA)viruses have been rarely found in fungi,and the evolutionary and ecological relationships among ssDNA viruses infecting fungi and other organisms remain unclear.In this study,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(3185 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-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 fungal 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 DsCDV1 P3 is systematically localized in the plasmodesmata,while its expression in trans-complementation experiments could restore systematic infection of a movement-deficient plant virus,suggesting that P3 is 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.

关 键 词：circular single-stranded DNA virus MYCOVIRUS virus evolution Genomoviridae Gegemycoviridae Diaporthe sojae circular DNA virus 1 

分 类 号：Q94[生物学—植物学]