The AID 3'UTR. (A) Cartoon of AID 3'UTR miR target sites (TS) and internal (False) polyA (not to scale) (DNA sequence shown). MicroRNA alignments are shown with corresponding binding affinities (kcal/mol). Vertical lines indicate complementary base pairing. Dotted vertical lines indicate G:U base pairing. PolyA, AATAAA eukaryotic polyadenylation signal. Arrows indicate RT-PCR primer sets for confirmation of expression. (B) RT-PCR to test expression of the AID 3'UTR miR-155 and miR-93 target site (TS) sequences in Ramos and MCF-7 cells.