The pathway of miRNA maturation.

MicroRNAs (miRNAs) are a novel class of 17-23 nucleotide short, nonprotein-coding RNA molecules which have emerged to be key players in posttranscriptional gene regulation. In this chapter we give an in-depth review of the classic, canonical mammalian miRNA maturation pathway and discuss new, noncanonical alternatives such as the mirtron pathway which were recently described.