are encoded by the same primary transcript, but on the opposite strand, as the miR-132 and miR-212 miRNAs, respectively (Remenyi et al., 2010). Moreover, each of these four miRNAs likely have their own unique set of target mRNA transcripts. Intriguingly, even though these four miRNAs are transcribed in equal measure (by virtue of all being encoded in the same primary transcript), their relative abundance varies dramatically within various cell types including neurons, with miR-132 being far more abundant than the other three transcripts (Remenyi et al., 2010). Hence, it is likely that as yet uncharacterized mechanisms are involved in preferentially stabilizing miR-132 levels, and/or destabilizing miR-132*, miR-212, and miR-212*.
