Sequence analysis of the coat protein and 3 '-noncoding region for Korean and other strains of sweet potato feathery mottle virus

The 3'-terminal regions of the genomic RNAs of two Korean isolates of sweet potato feathery mottle potyvirus (SPFMV) were cloned and their nucleotide sequences of full-length coat protein (CP) gene and 3' noncoding region (NC R) were determined. The CP of the two Korean isolates contained 315 amino a cid residues, The CP cistron sequences of the Korean isolates exhibit 72.7% to 98.7% nucleotide sequence identity and 79.9% to 99.0% amino acid identi ty when compared,vith those of 8 other known SPFMV strains. Pairwise compar ison revealed sequence similarities of 47.4% to 62.1% at the nucleotide lev el, and 48.6% to 70.2% at the amino acid level between SPFMV and 21 other p otyviruses. SPFMV CP has extensive amino acid sequence similarity to the ot her members of the genus Potyvirus throughout its central and C-terminal re gions. The 3' NCR of the SPFMV showed 42.5% to 99.1% nucleotide sequence id entities among the strains. The 3' NCR of SPFMV revealed 19.9% to 63.6% seq uence similarities to those of 21 other potyviruses. These results support the assignment of SPFMV as a distinct member of the genus Potyvirus of the family Potyviridae.