title: RNA interference induced by siRNAs modified with 4'-thioribonucleosides in cultured mammalian cells.
abstract: Short interfering RNAs (siRNAs) variously modified with 4'-thioribonucleosides against the Photinus luciferase gene were tested for their induction of the RNA interference (RNAi) activity in cultured NIH/3T3 cells. Results indicated that modifications at the sense-strand were well tolerated for RNAi activity except for full modification with 4'-thioribonucleosides. However, the activity of siRNAs modified at the antisense-strand was dependent on the position and the number of modifications with 4'-thioribonucleosides. Since modifications of siRNAs with 4'-thioribonucleosides were well tolerated in RNAi activity compared with that of 2'-O-methyl nucleosides, 4'-thioribonucleosides might be potentially useful in the development of novel and effective chemically modified siRNAs.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-Ku, Sapporo 060-0812, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Hoshika
authors.forename: Noriaki
authors.initials: N
authors.lastname: Minakawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kamiya
authors.forename: Hideyoshi
authors.initials: H
authors.lastname: Harashima
authors.forename: Akira
authors.initials: A
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D001483:Base Sequence; D048888:Fireflies / Q000201:enzymology / Q000235:genetics; D020128:Inhibitory Concentration 50; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D015394:Molecular Structure; D041681:NIH 3T3 Cells; D009705:Nucleosides / Q000737:chemistry*; D010766:Phosphorylation; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D009705:Nucleosides; D034741:RNA, Small Interfering; D013438:Sulfhydryl Compounds; D008156:Luciferases