Fig. 4.

Structure of terminal UTRs. (A) Hairpin loops near the 5′ ends of genomes of small RNA phages. (B) Structure of 3′ ends of small RNA phages. Sequence is displayed only for ϕCb5; for other phages, the schematic structures of stem-loops are shown. The RP termination codon in the R1 loop is boxed, and the conserved sequence in the U1 loop is circled. RP termination codons are shown as black boxes. Names of stem-loops and the long-distance interaction region (LD IX) are adopted from reference 10.