Figure 2.

Canonical pathway of miRNA biogenesis. In the nucleous pri-miRNA is produced by poly-II or III then cleaved by Drosh/DGCR8 microprocessor complex resulting in a stem loop pre-miRNA. Pre-miRNA is then expeled to the cytoplasm by Exp-5/RAN-GTP and Dicer along with the transactivating response RNA binding protein (TRBP) cleaves the stem loop structure to a double stranded mature miRNA. Where the guide strand of miRNA along Ago2 protein are loaded into the RISC guiding it to its functional destination, whereas the passenger strand is reported to be either degraded or may hold functional roles in regulating miRNAs homeostasis.