CLONING AND CHARACTERIZATION OF MYCOVIRUS DOUBLE-STRANDED-RNA FROM THE PLANT-PATHOGENIC FUNGUS, FUSARIUM-SOLANI F-SP ROBINIAE

A mycovirus (named FusoV) from the phytopathogenic fungus, Fusarium so lani f. sp. robiniae SUF704, has two kinds of double-stranded (ds) RNA genomes, designated M1 and M2. The cDNAs were constructed from FusoV genomic dsRNAs, The sequences of M1 and M2 cDNAs comprised 1645 and 14 45bp, respectively, Sequence analysis showed that each dsRNA had a sin gle long open reading frame (ORF) on only one of the strands, M1 ORF e ncodes a 519-amino acid residue polypeptide with a predicted molecular mass of 60 kDa, RNA-dependent RNA polymerase-conserved motifs were id entified in the predicted amino acid sequence, and the polymerase synt hesized dsRNA in vitro, The M2 ORF encodes a polypeptide of 413 amino acid residues with a predicted molecular mass of 44 kDa, The predicted amino acid sequence contained the sequence corresponding to those fou nd in the purified 44-kDa capsid protein of FusoV.