Endoribonuclease Dicer (DICER1)

Double-stranded RNA (dsRNA) endoribonuclease playing a central role in short dsRNA-mediated post-transcriptional gene silencing. Cleaves naturally occurring long dsRNAs and short hairpin pre-microRNAs (miRNA) into fragments of twenty-one to twenty-three nucleotides with 3' overhang of 2 nucleotides, producing respectively short interfering RNAs (siRNA) and mature microRNAs.

SiRNAs and miRNAs serve as guide to direct the RNA- induced silencing complex (RISC) to complementary RNAs to degrade them or prevent their interpretation. Gene silencing mediated by siRNAs, also referred to as RNA interference, controls the removal of transcripts from mobile and repetitive DNA elements of the genome but also the degradation of exogenous RNA of viral origin for instance.