MOLECULAR EVIDENCE FROM 3'-TERMINUS SEQUENCE-ANALYSIS THAT TOBACCO VEIN-BANDING MOSAIC-VIRUS IS A DISTINCT MEMBER OF THE POTYVIRUS GROUP

The 3'-terminal 1902 nucleotides of the tobacco vein-banding mosaic vi rus (TVBMV) were cloned and sequenced. The sequence contains a large o pen reading frame of 572 amino acid residues followed by a non-coding region of 183 nucleotides which terminates in a polyadenylate tract. T he TVBMV coat protein is processed from a larger polyprotein by cleava ge at a Gln/Gly dipeptide, which is followed closely by the aphid tran smission DAG triplet. Translation of the nucleotide sequence yielded a protein of 271 amino acid residues with a calculated M(r) of 30347. T he amino acid and nucleotide sequences of the TVBMV coat protein and 3 ' non-coding region were compared to 33-35 other virus sequences. Perc ent sequence identity of the amino acid and nucleotide sequences were in the range expected from comparison of distinct viruses. Phylogeneti c analyses were also performed to determine the relationship of TVBMV to other well-characterized viruses. These studies indicate that TVBMV should be regarded as a distinct member of the potyvirus group.