siRNA and miRNA: an insight into RISCs.
Two classes of short RNA molecule, small interfering RNA (siRNA) and microRNA (miRNA), have been identified as sequence-specific posttranscriptional regulators of gene expression. siRNA and miRNA are incorporated into related RNA-induced silencing complexes (RISCs), termed siRISC and miRISC, respectively. The current model argues that siRISC and miRISC are functionally interchangeable and target specific mRNAs for cleavage or translational repression, depending on the extent of sequence complementarity between the small RNA and its target. Emerging evidence indicates, however, that siRISC and miRISC are distinct complexes that regulate mRNA stability and translation. The assembly of RISCs can be traced from the biogenesis of the small RNA molecules and the recruitment of these RNAs by the RISC loading complex (RLC) to the transition of the RLC into the active RISC. Target recognition by the RISC can then take place through different interacting modes.
Tang
Guiliang
G
Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA. guiliang.tang@umassmed.edu
D000818:Animals; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D020365:RNA Helicases / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*; D034743:RNA-Induced Silencing Complex / Q000235:genetics / Q000378:metabolism*; D043244:Ribonuclease III / Q000378:metabolism
D035683:MicroRNAs; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D034743:RNA-Induced Silencing Complex; D043244:Ribonuclease III; D020365:RNA Helicases