Molecular and phylogenetic characteristics of sunflower isolate of Bean ‎yellow mosaic virus ‎

Bean yellow mosaic virus</em> (BYMV) is one of the most important members of the genus Potyvirus</em> that is distributed worldwide. In the present study, the complete genome sequence and molecular characteristics of a BYMV sunflower isolate (BYSun) from Iran has been reported. The complete nucleotide sequence of BYSun was determined using degenerate and specific primers and 5`-RACE. The viral genome comprises 9547 nucleotides, excluding a 3´</sup>-terminal poly (A) sequence. The genome of BYSun has a 206 nt 5´-non coding and a 171 nt 3´-non coding region. The RNA encodes a single polyprotein of 3056 amino acid residues and has a deduced genome organization typical for the members of the genus Potyvirus</em> and nine cleavage sites of the polyprotein were predicted. The small overlapping ORF (PIPO) in the P3 gene was also deduced. When analyzed using the RDP4 program, at least one recombination breakpoint was identified in BYSun genome. BYSun along with 23 full-length sequences of BYMV isolates from Genbank were subjected to phylogenetic analysis that showed the highest nucleotide and amino acid sequence identitywith Australian isolate of BYMV-S isolated from Broad bean. Phylogenetic analysis of different BYMV isolates sequences revealed existence of six to eight phylogenetic groupings depending on parts of investigated genome. BYSun and BYMV-S grouped apart from other isolates and were placed within a distinct group, currently designated “S”. This is the first report of a full-length sequence of a BYMV isolate from Iran.