Non-templated nucleotide addition to the 3′ end of miR-122 is suppressed in liver tissue from patients with HCV and in Huh7 cells expressing HCV core protein or infected with HCV.

<p>(A) Analysis of miR-122 isomers identified by the deep sequencing of small RNA libraries from human liver biopsies. Fold change (log2) of the proportion of each miR-122 isomer (each isomer read count divided by the total count of miR-122 isomers) in the indicated specimens compared with the corresponding value in the normal liver tissue (N-1). (B) Fold-change analysis for the 23-nt isomers as described in (A). Isomers are sorted according to their 3′-end dinucleotide sequences. Presented at the top is the pri-miR-122 sequence showing processing sites (blue arrows) for the 22-nt prototype miR-122 and an aberrant 3′-terminal processing site (black arrow) for the 23-nt isomer bearing a template-derived 3′ GU-tail. (C) Proportions (% of each isomer read count compared with the total read counts of the four major isomers shown at the top) of four major miR-122 isomers (isomers whose relative percentage to the total read counts of miR-122 isomers is >2%) in the indicated liver biopsies. (D) Proportions of four major miR-122 isomers in Huh7 cells transiently expressing HCV core protein (Core) or infected with HCV.