The full‑length genome sequence of a novel polymycovirus infecting the phytopathogenic fungus Botryosphaeria dothidea

Here, a novel dsRNA virus belonging to the family Polymycoviridae was identified in the phytopathogenic fungal strain B. dothidea ZM200473 and tentatively named "Botryosphaeria dothidea polymycovirus 2" (BdPmV2). The genome of BdPmV2 consists of five genomic dsRNA segments, ranging in size from 1224 to 2407 bp, each containing an open reading frame (ORF). ORF1 encodes a conserved RNA-dependent RNA polymerase (RdRP) consisting of 763 amino acids (aa) with a molecular mass (Mr) of 84.03 kDa, ORF3 encodes a putative methyltransferase (Met) consisting of 627 amino acids (aa) with an Mr of 68.41 kDa, ORF4 encodes a P-A-S-rich protein that serves as a coat protein (CP) consisting of 261 amino acids (aa) with an Mr of 27.60 kDa. ORF2 and ORF5 encode putative proteins with unknown functions, consisting of 697 amino acids (aa) with an Mr of 76.49 kDa and 323 amino acids (aa) with an Mr of 33.92 kDa, respectively. BLASTp analysis revealed that the RdRP protein of BdPmV2 had the highest similarity (56.52% identity) to that of a virus previously identified as "Aspergillus fumigatus polymycovirus 1". Phylogenetic analysis based on RdRP aa sequences indicated that BdPmV2 is a new member of the family Polymycoviridae.