FIG. 3.
Demonstration of the NotI tag in the genome RNA of recombinant BRSVs. RT-PCR was performed on total RNA of BSR T7/5 cells infected with standard BRSV ATue51908 or with recombinant virus by using positive-sense primers annealing to the genome 3′ ends and a negative-sense primer binding in the NS1 gene. No PCR product was detected when the RT step was omitted. Digestion with NotI of the 324-bp (calculated size) RT-PCR product originating from recombinant viruses yielded two bands of calculated sizes of 82 and 242 bp, whereas the RT-PCR product from standard BRSV strain ATue51908 was not cleaved.