摘要：
Here, we report the molecular characterization of a novel partitivirus fromPhomopsis vexansstrain PvHZ002, a plant-pathogenic fungus infecting eggplant. The virus was designated "Phomopsis vexans partitivirus 1" (PvPV1). PvPV1 contains two dsRNA segments, dsRNA1 and dsRNA2, which are 1,662 bp and 1,628 bp long, respectively. Each segment contains a single open reading frame, putatively encoding RNA-dependent RNA polymerase (dsRNA 1) and capsid protein (dsRNA 2). A homology search and phylogenetic analysis showed that PvPV1 clustered with viruses of the genusDeltapartitivirusof the familyPartitiviridae.
摘要：
Three dsRNAs, in sizes of approximately 2.5(-)5 kbp, were detected in the plant pathogenic fungus Nigrospora oryzae strain CS-7.5-4. Genomic analysis showed that the 5.0 kb dsRNA was a victorivirus named as Nigrospora oryzae victorivirus 2 (NoRV2). The genome of NoRV2 was 5166 bp in length containing two overlapping open reading frames (ORFs), ORF1 and ORF2. ORF1 was deduced to encode a coat protein (CP) showing homology to the CPs of viruses belonging to the Totiviridae family. The stop codon of ORF1 and the start codon of ORF2 were overlapped by the tetranucleotide sequence AUGA. ORF2 was predicted to encode an RNA-dependent RNA polymerase (RdRp), which was highly similar to the RdRps of victoriviruses. Virus-like particle examination demonstrated that the genome of NoRV2 was solely encapsidated by viral particles with a diameter of approximately 35 nm. The other two dsRNAs that were less than 3.0 kb were predicted to be the genomes of two mitoviruses, named as Nigrospora oryzae mitovirus 1 (NoMV1) and Nigrospora oryzae mitovirus 2 (NoMV2). Both NoMV1 and NoMV2 were A-U rich and with lengths of 2865 and 2507 bp, respectively. Mitochondrial codon usage inferred that each of the two mitoviruses contains a major large ORF encoding a mitoviral RdRp. Horizontal transfer experiments showed that the NoMV1 and NoMV2 could be cotransmitted horizontally via hyphal contact to other virus-free N. oryzae strains and causes phenotypic change to the recipient, such as an increase in growth rate. This is the first report of mitoviruses in N. oryzae.
作者：
Guo, Jun;Zhu, Jun Zi;Zhou, Xin Yu;Zhong, Jie;Li, Cai Hong;...
期刊：
Archives of Virology,2019年164(10):2631-2635 ISSN：0304-8608
通讯作者：
Zhang, Zhi Gang;Zhu, Hong Jian
作者机构：
[Zhong, Jie; Guo, Jun; Zhou, Xin Yu; Zhu, Jun Zi] Hunan Agr Univ, Hunan Prov Key Lab Biol & Control Plant Dis & Ins, Nongda Rd 1, Changsha 410128, Hunan, Peoples R China.;[Li, Cai Hong; Zhang, Zhi Gang; Zhu, Hong Jian; Zhang, ZG] Cotton Sci Res Inst Hunan, Changde 415101, Hunan, Peoples R China.;[Li, Cai Hong; Zhang, Zhi Gang; Zhu, Hong Jian; Zhang, ZG] Natl Hybrid Cotton Res Promot Ctr, Changde 415101, Hunan, Peoples R China.
通讯机构：
[Zhang, ZG; Zhu, HJ] C;[Zhang, ZG; Zhu, HJ] N;Cotton Sci Res Inst Hunan, Changde 415101, Hunan, Peoples R China.;Natl Hybrid Cotton Res Promot Ctr, Changde 415101, Hunan, Peoples R China.
摘要：
In this study, a novel mycovirus designed Colletotrichum gloeosporioides ourmia-like virus 1 (CgOLV1) was isolated from a filamentous phytopathogenic fungus, Colletotrichum gloeosporioides. The virus has a genome of 2,516 nucleotides and contains a large open reading frame (ORF) encoding an RNA-dependent RNA polymerase (RdRp). Phylogenetic analysis indicated that CgOLV1 is located in the ourmia-like mycovirus clade, whose members are related to plant ourmiaviruses. To the best of our knowledge, this is the first report of an ourmia-like mycovirus in C. gloeosporioides.
摘要：
In this study, we report the molecular characterization of a novel mycovirus in a phytopathogenic fungus of the species Colletotrichum gloeosporioides, which we named "Colletotrichum gloeosporioides RNA virus 1" (CgRV1). The virus has a dsRNA genome of 2,975 bp and possesses two non-overlapping open reading frames (ORFs 1 and 2). The smaller ORF1 encodes a protein of unknown function, and the larger ORF2 encodes the RNA-dependent RNA polymerase (RdRp). Phylogenetic analysis based on the RdRp sequence showed that CgRV1 clustered with and is closely related to unclassified mycoviruses that are distinct from members of the family Partitiviridae.
摘要：
We report the molecular attributes of a novel bisegmented double-stranded RNA (dsRNA) virus, designated "Nigrospora oryzae partitivirus 1" (NoPV1), from a phytopathogenic fungus Nigrospora oryzae. The genome of NoPV1 contains two dsRNA segments (dsRNA1 and 2), 1875 bp and 1601 bp in length, respectively. dsRNA1 and -2 both have a single open reading frame encoding the RNA-dependent RNA polymerase and coat protein, respectively. NoPV1 has a high degree of sequence identity to members of genus Gammapartitivirus in the family Partitiviridae. This is the first report of a mycovirus in the family Partitiviridae that infects N. oryzae.
摘要：
In this study, we report the discovery and molecular characterization of a novel mycovirus, Nigrospora oryzae fusarivirus 1 (NoFV1) isolated from the rice-infecting fungus Nigrospora oryzae. Excluding a poly (A) tail, the genome of the virus is 7004 nucleotide (nt) long containing three putative nonoverlapping open reading frames (ORF1, ORF2, and ORF3). The large ORF1 encodes a polypeptide with a conserved RNA-dependent RNA polymerase (RdRp) domain and a helicase domain that functions for RNA replication. Each of the smaller ORF2 and the smallest ORF3 encodes a putative protein with an unknown function. Amino acid (aa) sequence similarities between the NoFV1-ORF1- and ORF2-encoded proteins and the homologous sequences from other mycoviruses were found. Phylogenetic analysis on the basis of the RdRp and helicase domains showed that NoFV1 is phylogenetically related to viruses in the newly proposed family Fusariviridae. Thus, we suggest that NoFV1 might be a novel member of family Fusariviridae.
作者：
Zhong, Jie;Zhou, Qian;Hu, Yue;Zhu, Hong Jian;Gao, Bi Da*
期刊：
Virus Genes,2016年52(1):156-159 ISSN：0920-8569
通讯作者：
Gao, Bi Da
作者机构：
[Gao, Bi Da; Zhong, Jie; Zhou, Qian; Zhu, Hong Jian; Hu, Yue] Hunan Agr Univ, Hunan Prov Key Lab Biol & Control Plant Dis & Ins, Nongda Rd 1, Changsha 410128, Hunan, Peoples R China.;[Zhu, Hong Jian] Hunan Agr Univ, Southern Reg Collaborat Innovat Ctr Grain & Oil C, Changsha, Hunan, Peoples R China.
通讯机构：
[Gao, Bi Da] H;Hunan Agr Univ, Hunan Prov Key Lab Biol & Control Plant Dis & Ins, Nongda Rd 1, Changsha 410128, Hunan, Peoples R China.
关键词：
Victorivirus;Nigrospora oryzae;Mycovirus
摘要：
Nigrospora oryzae is a worldwide phytopathogenic fungus that can infect many plant host species. In this study, complete sequence of a novel mycovirus from N. oryzae was reported. The viral genome is 5100 base pairs in length and possesses two overlapping open reading frames (ORFs). The two ORFs potentially encode proteins that showed significant similarity to the capsid protein and RNA-dependent RNA polymerase, in the family Totiviridae, respectively. Phylogenetic tree showed that this novel mycovirus is a new member of the genus Victorivirus in the family Totiviridae. We here designated the virus as Nigrospora oryzae victorivirus 1 (NoRV1), the first putative victorivirus identified in N. oryzae.
关键词：
Plant Virus;Rice Blast;Multiple Protein Alignment;Amino Acid Triplet;Amplify cDNA Product
摘要：
Here, we report a novel virus isolated from rice blast fungus, Magnaporthe oryzae, an important plant pathogen. This virus has an RNA genome of 3246 nucleotides. Its genome possesses two in-frame open reading frames (ORFs). The smaller ORF1 encodes a protein with significant similarity to a protein encoded by the ssRNA mycovirus Diaporthe ambigua RNA virus 1 (DaRV1). The larger ORF2 encodes a protein with similarity to RNA-dependent RNA polymerases (RdRp) of DaRV1 and other plant viruses of the family Tombusviridae. In silico analysis and comparisons with DaRV1 genome expression suggest that ORF2 is translated via a readthrough mechanism together with ORF1. Based upon results of this study, this virus, for which the provisional name Magnaporthe oryzae virus A (MoVA) is proposed, belongs to a new virus species. Furthermore, MoVA along with DaRV1 belong to a new taxon of mycoviruses that are evolutionarily related to plant viruses belonging to the family Tombusviridae.
