Schematic of the self-complementary bottom and top stem constructs of ZIKV SLA. (A) Schematic representation of Zika virus genome. The genome contains one open reading frame (ORF), flanked by a highly structured 5′ untranslated region (UTR) and a 3′ UTR. The stem–loop A (SLA) structure is located at the 5′ terminus of the 5′ UTR (boxed). (B) The secondary structure of ZIKV SLA based on the 3D structure (Lee et al. 2021). The SLA sequences used for the bottom stem (brown) and top stem (blue) constructs are indicated. (C) Design of bottom stem construct. The GGGCCC linker sequence (pink) connects the U13 and A62 nucleotides of the bottom stem in ZIKV SLA. The RNA construct dimerizes with two identical bottom stem sites, outlined in boxes. (D) Design of top stem construct. The GGGCCC linker sequence (pink) connects the A31 and U36 nucleotides of the top stem in ZIKV SLA. The construct dimerizes with two top stem sites, outlined in boxes.
