title: Double-stranded regions are essential design components of potent inhibitors of RISC function.
abstract: While microRNAs (miRNAs) are recognized as playing a critical role in regulating eukaryotic gene expression, both the mechanism by which these small, noncoding RNAs function and the genes they target remain elusive. Previous studies have shown that short, single-stranded 2'-O-methyl-modified oligonucleotides that are complementary to mature microRNA sequences can interact with the miRNA-RISC nucleoprotein complex and weakly inhibit miRNA function. Here we report the identification of secondary structural elements that enhance the potency of these molecules. Incorporation of highly structured, double-stranded flanking regions around the reverse complement core significantly increases inhibitor function and allows for multi-miRNA inhibition at subnanomolar concentrations. The improved functionality of these double-stranded miRNA inhibitors may provide insights into the miRNA mechanism by suggesting the possible importance of such structures in or near endogenous miRNA target sites.
authors.affiliation: Thermo Fisher Scientific, Dharmacon Products, Lafayette, Colorado 80026, USA. annaleen.vermeulen@thermofischer.com
authors.forename: Annaleen
authors.initials: A
authors.lastname: Vermeulen
authors.forename: Barbara
authors.initials: B
authors.lastname: Robertson
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Dalby
authors.forename: William S
authors.initials: WS
authors.lastname: Marshall
authors.forename: Jon
authors.initials: J
authors.lastname: Karpilow
authors.forename: Devin
authors.initials: D
authors.lastname: Leake
authors.forename: Anastasia
authors.initials: A
authors.lastname: Khvorova
authors.forename: Scott
authors.initials: S
authors.lastname: Baskerville
mesh_terms: D002460:Cell Line; D015195:Drug Design; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology*; D005821:Genetic Techniques; D006801:Humans; D035683:MicroRNAs / Q000037:antagonists & inhibitors*; D016372:RNA, Antisense / Q000737:chemistry / Q000235:genetics; D012330:RNA, Double-Stranded / Q000737:chemistry*; D034743:RNA-Induced Silencing Complex / Q000037:antagonists & inhibitors*; D013329:Structure-Activity Relationship
chemical_list: D004791:Enzyme Inhibitors; D035683:MicroRNAs; D016372:RNA, Antisense; D012330:RNA, Double-Stranded; D034743:RNA-Induced Silencing Complex