RNA Interference in the Nucleus

摘要

RNA-guided gene silencing pathways use double-stranded RNA (dsRNA) to inhibit gene expression in a sequence-specific manner. In RNA interference (RNAi), dsRNA is processed to small interfering RNAs (siRNAs), which guide the cleavage of complementary RNA molecules by the RNA-induced silencing complex (RISC) (1). Members of the Argonaute protein family are the direct binding partners of siRNAs and form the core of RISC (2,3). Although RNAi predominantly occurs in the cell's cytoplasm, nuclear RNAs can be targeted by siRNAs as well. A study by Guang et al. on page 537 of this issue now reports the identification of an Argonaute protein in the worm Caenorhabditis elegans that is required for nuclear siRNA import and is therefore essential for nuclear RNAi (4).