Development of MicroRNAs as Potential Therapeutics against Cancer

Figure 1

MicroRNA biogenesis pathway. miRNA genes are transcribed to produce primary miRNA transcript (pri-miRNA) by RNA polymerase II and cleaved into precursor miRNA transcript (pre-miRNA) by the microprocessor complex Drosha-DGCR8 in the nucleus. The pre-miRNA is then exported into the cytoplasm by Exportin-5 where it is processed into miRNA duplex by Dicer and its interacting partner, TRBP. The miRNA duplex is then unwound into two single-stranded miRNAs. The functional strand of mature miRNA is uploaded onto the RNA-induced silencing complex (RISC) and negatively regulates gene expression resulting in either target mRNA degradation or translation repression, while the passenger strand is degraded.