Complete genome sequence of a novel mitovirus detected in Paris polyphylla var. yunnanensis.

Abstract

Paris mitovirus 1 (ParMV1) is a positive-sense RNA virus that was detected in diseased Paris polyphylla var. yunnanensis plants in Wenshan, Yunnan. The complete genome sequence of ParMV1 is 2,751 nucleotides in length, and the genome structure is typical of mitoviruses. The ParMV1 genome has a single open reading frame (ORF; nt 358-2,637) that encodes an RNA-dependent RNA polymerase (RdRp) with a predicted molecular mass of 86.42 kDa. ParMV1 contains six conserved motifs (Ι-VΙ) that are unique to mitoviruses. The 5' and 3' termini of the genome are predicted to have a stable secondary structure, with the reverse complementary sequence forming a panhandle structure. Comparative genome analysis revealed that the RdRp of ParMV1 shares 23.1-40.6% amino acid (aa) and 32.3-45.7% nucleotide (nt) sequence identity with those of other mitoviruses. Phylogenetic analysis based on RdRp aa sequences showed that ParMV1 clusters with mitoviruses and hence should be considered a new member of the genus Mitovirus in the family Mitoviridae. This is the first report of a novel mitovirus infecting Paris polyphylla var. yunnanensis.