Alignment of amino acid sequences of accessory proteins R3 and G4 of BLV isolates. In (A) alignment of G4 sequences is shown. The leader peptide is shown in green, and the two putative cellular protease cleavage sites are indicated by inverted triangles on top of the alignment. The myb-like motif (MYB) and the arginine-rich nucleus targeting RNA-binding region (ARR) are shown in red. In (B) alignment of R3 sequences are shown. Termination codons are shown by an asterisk and indicated by an arrow.