Characterization of a Fungal Virus Representing a Novel Genus in the Family Alphaflexiviridae

Ting Ye; Zhongbo Lu; Han Li; Jie Duan; Du Hai; Yang Lin; Jiatao Xie; Jiasen Cheng; Bo Li; Tao Chen; Yanping Fu; Daohong Jiang

doi:10.3390/v15020339

Characterization of a Fungal Virus Representing a Novel Genus in the Family Alphaflexiviridae

Viruses. 2023 Jan 25;15(2):339. doi: 10.3390/v15020339.

Authors

Ting Ye^{1

2}, Zhongbo Lu^{1

2}, Han Li^{1

2}, Jie Duan^{1

2}, Du Hai^{1

2}, Yang Lin², Jiatao Xie^{1

2}, Jiasen Cheng^{1

2}, Bo Li^{1

2}, Tao Chen^{1

2}, Yanping Fu², Daohong Jiang^{1

2}

Affiliations

¹ State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, China.
² Hubei Key Laboratory of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.

Abstract

Sclerotinia sclerotiorum is an ascomycetous fungus and hosts various mycoviruses. In this study, a novel fungal alphaflexivirus with a special genomic structure, named Sclerotinia sclerotiorum alphaflexivirus 1 (SsAFV1), was cloned from a hypovirulent strain, AHS31. Strain AHS31 was also co-infected with two botourmiaviruses and two mitoviruses. The complete genome of SsAFV1 comprised 6939 bases with four open reading frames (ORFs), a conserved 5'-untranslated region (UTR), and a poly(A) tail in the 3' terminal; the ORF1 and ORF3 encoded a replicase and a coat protein (CP), respectively, while the function of the proteins encoded by ORF2 and ORF4 was unknown. The virion of SsAFV1 was flexuous filamentous 480-510 nm in length and 9-10 nm in diameter. The results of the alignment and the phylogenetic analysis showed that SsAFV1 is related to allexivirus and botrexvirus, such as Garlic virus X of the genus Allexivirus and Botrytis virus X of the genus Botrevirus, both with 44% amino-acid (aa) identity of replicase. Thus, SsAFV1 is a novel virus and a new genus, Sclerotexvirus, is proposed to accommodate this novel alphaflexivirus.

Keywords: Alphaflexiviridae; Sclerotinia sclerotiorum; flexivirus; mycovirus.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acids
Flexiviridae*
Fungal Viruses* / genetics
Nucleotidyltransferases
Phylogeny
RNA, Messenger

Substances

Amino Acids
Nucleotidyltransferases
RNA, Messenger

Supplementary concepts

Sclerotinia sclerotiorum

Grants and funding

This research was supported by the Wuhan Science and Technology Project (2020020601012260), the Fundamental Research Funds for the Central Universities (2662022PY001), and the fund earmarked for CARS-12.