Molecular characterization of a novel victorivirus infecting Corynespora cassiicola

Abstract

One victorivirus was detected in the isolate of Corynespora cassiicola strains 20180909-03, which was named Corynespora cassiicola victorivirus 1 (CcVV1). The whole-genome sequence of the virus was sequenced and identi ed. The CcVV1 genome is 5140 nt and contains 56.87%GC with two large open reading frames (ORFs) overlapping at the tetranucleotide AUGA. The two ORFs were predicted to encode coat protein (CP) and RNA-dependent RNA polymerase (RdRp) respectively, which were conservative in dsRNA fungal viruses of the family Totiviridae. Conservative domains comparison and phylogenetic analysis of the deduced amino acid sequence of RdRp and CP showed that CcVV1 was a new virus of the Victorivirus genus. As far as we know, it is the rst report of a genomic sequence of the genus Victorivirus infecting Corynespora cassiicola.

Molecular characterization of a novel victorivirus isolated from the phytopathogenic fungus Phaeobotryon rhois

“…1c). Furthermore, the tetranucleotide AUGA is widespread in victoriviruses [11,[13][14]. Besides, an H-type pseudoknot structure (GAAggagccgCggccGCUGCAggcc cggcuccCCAACAAUGA) at the upstream of the AUGA motif.…”

“…To date, members of the genera Victorivirus only infect fungi [6], including various phytopathogenic fungi, such as Aspergillus foetidus, Fusarium asiaticum, Nigrospora oryzae, Ustilaginoidea virens [7][8][9][10]. The genome of there viruses is nearly 5 kbp in size, and generally contains two ORFs, with the 5'-proximal ORF encoding the CP and the 3'-proximal ORF encoding the RdRp [5,11]. The termination codon of the CP overlaps with the initiation codon of the RdRp with junction sequence, typically AUGA or UAAUG.…”