Identification of known and orthologous miRNAs in the pig. A. Overlap of known porcine miRNAs and the orthologs of human miRNAs identified in this study. The total number of the identified miRNAs is indicated in parenthesis. Known, porcine miRNAs annotated in miRBase; Unidentified, known porcine miRNAs not identified in this study; Non-conserved, miRNAs that are not conserved between humans and pigs; Orthologous, miRNAs conserved between humans and pigs (indicated by a dot-border rectangle). B. Splinted ligation analysis (top) and quantification (bottom) of expression levels of the porcine ortholog of human miR-25-3p. A representative image from three independent experiments is shown. Orthologous but unidentified porcine miRNAs, miR-202-5p and miR-432-5p, served as negative controls, and the 5.8S rRNA was used as a loading control. Consistent with Solexa sequencing results, miR-25-3p was significantly down-regulated in ORF1- and ORF2-expressing PK15 cells but not in ORF3-expressing cells, compared with parental and empty vector-harboring cells. For quantification, the level of miR-25-3p in parental cells was set to 1. All error bars indicate mean ± standard error of the mean (SEM). ***, P < 0.001 by one-way analysis of variance (ANOVA) with Dunnett’s multiple-comparison test.