The process of RNA-interference in eukaryotic cells. Long precursor microRNA (miRNA), called pri-miRNA, is cleaved by RNase III endonuclease (Drosha) into pieces of approximately 70 nucleotides each (called pre-miRNA) in the nucleus. Following transportation into the cytoplasm by exportin 5 another RNase III endonuclease (Dicer) cleaves it into mature miRNA segments. Degradation of messenger RNA (mRNA) and translational repression occurs after miRNA binds to the RNA-induced silencing complex (RISC). Cytoplasmic long double-stranded RNA (dsRNA) is cleaved by Dicer into small interfering RNA (siRNA), which is incorporated into RISC, resulting in the cleavage and degradation of specific target mRNA. Synthetic double-stranded siRNA is not processed by Dicer and directly incorporated by the RISC.b26b3c24929628PubMedEri1: a conserved enzyme at the crossroads of multiple RNA-processing pathways.Trends Genet2014Thomas MFL'Etoile NDAnsel KM24384374PubMedLiposomal siRNA nanocarriers for cancer therapy.Adv Drug Deliv Rev2014Ozpolat BSood AKLopez-Berestein GRNA degradation pathwayPW:0001161Pathway Ontology