title: Silencing of microRNA families by seed-targeting tiny LNAs.
abstract: The challenge of understanding the widespread biological roles of animal microRNAs (miRNAs) has prompted the development of genetic and functional genomics technologies for miRNA loss-of-function studies. However, tools for exploring the functions of entire miRNA families are still limited. We developed a method that enables antagonism of miRNA function using seed-targeting 8-mer locked nucleic acid (LNA) oligonucleotides, termed tiny LNAs. Transfection of tiny LNAs into cells resulted in simultaneous inhibition of miRNAs within families sharing the same seed with concomitant upregulation of direct targets. In addition, systemically delivered, unconjugated tiny LNAs showed uptake in many normal tissues and in breast tumors in mice, coinciding with long-term miRNA silencing. Transcriptional and proteomic profiling suggested that tiny LNAs have negligible off-target effects, not significantly altering the output from mRNAs with perfect tiny LNA complementary sites. Considered together, these data support the utility of tiny LNAs in elucidating the functions of miRNA families in vivo.
authors.affiliation: Santaris Pharma, Hørsholm, Denmark.
authors.forename: Susanna
authors.initials: S
authors.lastname: Obad
authors.forename: Camila O
authors.initials: CO
authors.lastname: dos Santos
authors.forename: Andreas
authors.initials: A
authors.lastname: Petri
authors.forename: Markus
authors.initials: M
authors.lastname: Heidenblad
authors.forename: Oliver
authors.initials: O
authors.lastname: Broom
authors.forename: Cristian
authors.initials: C
authors.lastname: Ruse
authors.forename: Cexiong
authors.initials: C
authors.lastname: Fu
authors.forename: Morten
authors.initials: M
authors.lastname: Lindow
authors.forename: Jan
authors.initials: J
authors.lastname: Stenvang
authors.forename: Ellen Marie
authors.initials: EM
authors.lastname: Straarup
authors.forename: Henrik Frydenlund
authors.initials: HF
authors.lastname: Hansen
authors.forename: Troels
authors.initials: T
authors.lastname: Koch
authors.forename: Darryl
authors.initials: D
authors.lastname: Pappin
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Hannon
authors.forename: Sakari
authors.initials: S
authors.lastname: Kauppinen
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D005260:Female; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D017930:Genes, Reporter; D005821:Genetic Techniques; D006367:HeLa Cells; D006801:Humans; D008099:Liver / Q000378:metabolism; D049410:Luciferases, Renilla / Q000235:genetics; D008325:Mammary Neoplasms, Experimental / Q000235:genetics / Q000473:pathology / Q000628:therapy; D051379:Mice; D008807:Mice, Inbred BALB C; D035683:MicroRNAs / Q000037:antagonists & inhibitors* / Q000235:genetics; D009841:Oligonucleotides / Q000008:administration & dosage / Q000235:genetics* / Q000493:pharmacokinetics
chemical_list: D020413:3' Untranslated Regions; D035683:MicroRNAs; D009841:Oligonucleotides; C477371:locked nucleic acid; D049410:Luciferases, Renilla