Figure 1.

Structural organization of the HCV IRES (7), the initiation AUG codon is underlined. RNA sequences complementary to deoxy-oligomers used for site-specific modification of the HCV IRES are marked with thick lines with arrows indicating the 5′-phosphates derivatized with alkylating groups. RNA sequences complementary to helper oligomers used together with the alkylating derivatives are marked with dotted lines. Nucleotides of the HCV IRES cross-linked to the oligonucleotide derivatives are shaded.