MicroRNA (miRNA) production and processing. The pri-miRNA transcript is transcribed by RNA polymerase II. The stem loop structure is cleaved off by the microprocessor to generate pre-miRNA. The pre-miRNA is exported to the cytoplasm by exportin5 in a ran-GTP dependent manner. Once in the cytoplasm, the pre-miRNA is processed by Dicer creating a single stranded mature miRNA. This mature miRNA is bound by the RISC complex, guiding it to the 3'UTR of target mRNAs, leading to repression of protein expression.