Fig. 1.

Structure of P-PMO and schematic target locations of P-PMO in the PRRSV genome. (A) P-PMO structure. A morpholine ring and a phosphorodiamidate linkage in PMO replace the deoxyribose and phosphodiester linkage, respectively, of DNA. “B” represents the bases A, G, C, or T. The peptide R₅F₂R₄, designated P4, was covalently conjugated to the 5′-end of each PMO. (B) Positions of P-PMO target sites in PRRSV genomic RNA. The AUG translation initiation codon of ORF1a is shown after the 5′-UTR line. The arrows indicate the 5′–3′-orientation of the PMOs in relation to the PRRSV genome.