title: Passenger strand loading in overexpression experiments using microRNA mimics.
abstract: MicroRNAs (miRNAs) are important regulators of gene function and manipulation of miRNAs is a central component of basic research. Modulation of gene expression by miRNA gain-of-function can be based on different approaches including transfection with miRNA mimics; artificial, chemically modified miRNA-like small RNAs. These molecules are intended to mimic the function of a miRNA guide strand while bypassing the maturation steps of endogenous miRNAs. Due to easy accessibility through commercial providers this approach has gained popularity, and accuracy is often assumed without prior independent testing. Our in silico analysis of over-represented sequence motifs in microarray expression data and sequencing of AGO-associated small RNAs indicate, however, that miRNA mimics may be associated with considerable side-effects due to the unwanted activity of the miRNA mimic complementary strand.
authors.affiliation: a Department of Clinical Sciences, Lund ; Division of Oncology and Pathology ; Lund University Cancer Center at Medicon Village ; Lund , Sweden.
authors.forename: Rolf
authors.initials: R
authors.lastname: Søkilde
authors.forename: Inga
authors.initials: I
authors.lastname: Newie
authors.forename: Helena
authors.initials: H
authors.lastname: Persson
authors.forename: Åke
authors.initials: Å
authors.lastname: Borg
authors.forename: Carlos
authors.initials: C
authors.lastname: Rovira
mesh_terms: D060565:Argonaute Proteins / Q000378:metabolism; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002460:Cell Line; D045744:Cell Line, Tumor; D003198:Computer Simulation; D020869:Gene Expression Profiling / Q000379:methods*; D005786:Gene Expression Regulation; D006801:Humans; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D059372:Nucleotide Motifs / Q000235:genetics*; D012313:RNA / Q000235:genetics / Q000378:metabolism
chemical_list: D060565:Argonaute Proteins; C000605129:MIRN4728 microRNA, human; C560945:MIRN486 microRNA, human; D035683:MicroRNAs; D012313:RNA
keywords: AGO, Argonaute; Argonaute protein; GEO, Gene Expression Omnibus; HITS-CLIP, high-throughput sequencing of RNA isolated by crosslinking immunoprecipitation; OAS, oligoadenylate synthetase; PKR, protein kinase R; RISC, RNA-induced silencing complex; RNA interference; TLR3, Toll-like receptor 3; mRNA, mRNA; miRNA, microRNA; microRNA; mimic; nt, nucleotide; off-target effect; passenger strand; siRNA