Figure 2.

Novel Splicing of Pri-miR-137. The upper box contains the sequence of pri-miR-137 exon 3 with the splice sites indicated by asterisks. Canonical and alternative 5′ splicing of exon 3 is indicated by dashed lines above and below the region, respectively. Resulting canonical pri-miR-137 and del-miR-137 transcript isoforms are depicted along the bottom. Del-miR-137 transcripts do not contain the majority of pre-miR-137 sequence or the mature miR-137 sequence, which would down-regulate mature miR-137 levels. Expression of del-miR-137 transcript isoforms provides a novel regulatory mechanism for mature miR-137.