The BoHV-4 inner prDNA units contain conserved cleavage/packaging signals. Alignment of the prDNA-inner units from V.test strain (above) and 66-p-347 strain (below). The differences observed in the alignment are highlighted in grey. The cleavage/packaging signals pac-1 and pac-2 are represented in boxes, and their composing C-rich, G-rich, GC-rich and T-rich units are indicated. PstI, EcoRI, SstII, BamHI restriction sites are represented in coloured font.