Figure 1.

miRNA biogenesis pathway: miRNA genes are transcribed into the nucleus by RNA pol II into primary structures—pri-miRNA. The microprocessor complex composed of DROSHA and its binding partner DGCR8 cleaves the pri-miRNA into a hairpin pre-miRNA structure. The pre-miRNAs are then exported to cytoplasm by XPO5 where DICER processes the pre-miRNA into mature miRNA. The mature form is incorporated into RISC which will guide the mature miRNA to target mRNAs, regulating gene expression post-transcriptionally by mRNA degradation or translational repression. The figure was created with BioRender.com.