FIG. 4.

uORF mutations in the synthetic shunt-competent leader. Sequences are 3′-end aligned at the stem (represented by -@). Constructs with common 5′-proximal sequences are framed together, with dots introduced to facilitate the alignment. Restriction sites are in lowercase italics. uORF coding sequences are underlined, with the encoded peptides shown below. ∗a and ∗o indicate amber and ochre termination codons, respectively. Point mutations, insertions, and replacements are indicated in bold; Δ in A9 represents a 1-nt deletion. The uORF from AdoMetDc and GCN4 uORFs 1 and 4 (plus flanking sequences) are shown in bold in A6, A18, and A19, respectively. Sequence complementary to the 3′ end of the 18S rRNA is indicated in bold in A20.