The Nucleotide Sequence and Genome Organization of Mushroom Bacilliform Virus: A Single-Stranded RNA Virus of Agaricus bisporus (Lange) Imbach

doi:10.1006/viro.1994.1412

Virology

Volume 202, Issue 2, 1 August 1994, Pages 904-911

https://doi.org/10.1006/viro.1994.1412 Get rights and content

Abstract

Mushroom bacilliform virus (MBV) is found in association with spherical virus-like particles in cultivated mushrooms (Agaricus bisporus) afflicted with La France disease. MBV possesses a monopartite ssRNA genome of positive sense and differs from the majority of characterized mycoviruses, which contain segmented dsRNA genomes. We have cloned and sequenced the MBV genome and determined that its length is 4009 nucleotides. The MBV genome contains four major and three minor open reading frames and has 5′ and 3′ noncoding regions of 60 and 250 nucleotides, respectively. The putative RNA-dependent RNA polymerase and the coat protein display homology with corresponding proteins encoded by certain plant viruses, particularly luteoviruses and carmoviruses.

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Citation Excerpt :
The first mycoviruses known to science were the causative agents of the “La France disease” discovered in the cultivated button mushroom Agaricus bisporus (Hollings, 1962). Subsequently, viruses have been found also in other commercially cultivated macromycetes, including Lentinula edodes (shiitake), Pleurotus ostreatus (oyster mushroom), Flammulina velutipes (enokitake) and Grifola frondosa (maitake) (Magae, 2012; Magae and Sunagawa, 2010; Qiu et al., 2010; Revill et al., 1994; Ro et al., 2006, 2007; Komatsu et al., 2019; Lin et al., 2019). Viruses have also been detected in wild edible mushrooms (Sahin and Akata, 2018 and the references therein), including the commercially valuable ascomycetes of genus Tuber (true truffles) (Stielow et al., 2011a, 2011b; 2012; Stielow and Menzel, 2010) and basidiomycetes of genus Lactarius (Sutela and Vainio, 2020).
Virus communities of forest fungi remain poorly characterized. In this study, we detected two new viruses co-infecting an isolate of the polypore fungus Bondarzewia berkeleyi using high-throughput sequencing. One of them was a putative new partitivirus designated as Bondarzewia berkeleyi partitivirus 1 (BbPV1), with two linear dsRNA genome segments of 1928 and 1863 bp encoding a putative RNA-dependent RNA polymerase (RdRP) of 591 aa and a putative capsid protein of 538 aa. The other virus, designated as Bondarzewia berkeleyi negative-strand RNA virus 1 (BbNSRV1), had a non-segmented negative-sense RNA genome of 10,983 nt and was related to members of family Mymonaviridae. The BbNSRV1 genome includes six predicted open reading frames (ORFs) of 279, 425, 230, 174, 200 and 1970 aa. The longest ORF contained conserved regions corresponding to Mononegavirales RdRP and mRNA-capping enzyme region V constituting the mononegavirus Large protein. In addition, a low level of sequence identity was detected between the putative nucleocapsid protein-coding ORF2 of Lentinula edodes negative-strand RNA virus 1 and BbNSRV1. The viruses characterized in this study are the first ones described in Bondarzewia spp., and BbNSRV1 is the second mymona-like virus described in a basidiomycete host.
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Citation Excerpt :
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Regular ArticleThe Nucleotide Sequence and Genome Organization of Mushroom Bacilliform Virus: A Single-Stranded RNA Virus of Agaricus bisporus (Lange) Imbach

Abstract

Regular Article
The Nucleotide Sequence and Genome Organization of Mushroom Bacilliform Virus: A Single-Stranded RNA Virus of Agaricus bisporus (Lange) Imbach