title: Antisense inhibition of gene expression in cells by oligonucleotides incorporating locked nucleic acids: effect of mRNA target sequence and chimera design.
abstract: Use of antisense oligonucleotides is a versatile strategy for achieving control of gene expression. Unfortunately, the interpretation of antisense-induced phenotypes is sometimes difficult, and chemical modifications that improve the potency and specificity of antisense action would be useful. The introduction of locked nucleic acid (LNA) bases into oligonucleotides confers exceptional improvement in binding affinity, up to 10 degrees C per substitution, making LNAs an exciting option for the optimization of antisense efficacy. Here we examine the rules governing antisense gene inhibition within cells by oligonucleotides that contain LNA bases. LNA- containing oligomers were transfected into cells using cationic lipid and accumulated in the nucleus. We tested antisense gene inhibition by LNAs and LNA-DNA chimeras complementary to the 5'-untranslated region, the region surrounding the start codon and the coding region of mRNA, and identified effective antisense agents targeted to each of these locations. Our data suggest that LNA bases can be used to develop antisense oligonucleotides and that their use is a versatile approach for efficiently inhibiting gene expression inside cells.
authors.affiliation: Department of Pharmacology, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, TX 75390-9041, USA.
authors.forename: Dwaine A
authors.initials: DA
authors.lastname: Braasch
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Liu
authors.forename: David R
authors.initials: DR
authors.lastname: Corey
mesh_terms: D020121:5' Untranslated Regions; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D018387:Codon, Initiator; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems; D015195:Drug Design; D005786:Gene Expression Regulation; D008156:Luciferases / Q000096:biosynthesis / Q000235:genetics; D009691:Nucleic Acid Denaturation; D009693:Nucleic Acid Hybridization; D016376:Oligonucleotides, Antisense / Q000737:chemistry* / Q000494:pharmacology*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000737:chemistry* / Q000378:metabolism*; D013696:Temperature; D014162:Transfection
chemical_list: D020121:5' Untranslated Regions; D018387:Codon, Initiator; D016376:Oligonucleotides, Antisense; D012333:RNA, Messenger; D008156:Luciferases