FIG. 1.
Construction of the ORFV recombinants (A) The map locations of HindIII fragments and of the inverted terminal repeats (ITR) of the genome of ORFV strain D1701-V are depicted. (B) The PstI-HindIII fragment containing the VEGF-E and adjacent genes was cloned as plasmid pORF-PA. (C) The singular StyI restriction site in pORF-PA was used to delete the VEGF-E gene by a bidirectional Bal31 digest that resulted in plasmid pdV-550. (D) A synthetic linker covering the indicated restriction sites was inserted into the EcoRV site. The obtained plasmid, pdV-Rec1, contains the early promoter of VEGF-E (Pvegf-e) and the original early transcription stop motif T5NT. (E) The NcoI-HinfI fragment of plasmid pALM-20 containing the complete PRV gC gene was blunt-end ligated into the EcoRV site of pDV-Rec1, resulting in plasmid pdV-gC. (F) The use of the HindIII-BamHI fragment of plasmid pgDBSII allowed cloning of the complete gD gene of PRV in pdV-Rec1 to obtain plasmid pdVgD.