title: Asymmetric shorter-duplex siRNA structures trigger efficient gene silencing with reduced nonspecific effects.
abstract: Small interfering RNAs (siRNAs) are short, double-stranded RNAs that mediate efficient gene silencing in a sequence-specific manner by utilizing the endogenous RNA interference (RNAi) pathway. The current standard synthetic siRNA structure harbors a 19-base-pair duplex region with 3' overhangs of 2 nucleotides (the so-called 19+2 form). However, the synthetic 19+2 siRNA structure exhibits several sequence-independent, nonspecific effects, which has posed challenges to the development of RNAi therapeutics and specific silencing of genes in research. In this study, we report on the identification of truncated siRNA backbone structures with duplex regions shorter than 19 bp (referred to as asymmetric shorter-duplex siRNAs or asiRNAs) that can efficiently trigger gene silencing in human cell lines. Importantly, this asiRNA structure significantly reduces nonspecific effects triggered by conventional 19+2 siRNA scaffold, such as sense-strand-mediated off-target gene silencing and saturation of the cellular RNAi machinery. Our results suggest that this asiRNA structure is an important alternative to conventional siRNAs for both functional genomics studies and therapeutic applications.
authors.affiliation: Department of Chemistry, Pohang University of Science and Technology, Pohang, Korea.
authors.forename: Chan Il
authors.initials: CI
authors.lastname: Chang
authors.forename: Jae Wook
authors.initials: JW
authors.lastname: Yoo
authors.forename: Sun Woo
authors.initials: SW
authors.lastname: Hong
authors.forename: Shi Eun
authors.initials: SE
authors.lastname: Lee
authors.forename: Hye Suk
authors.initials: HS
authors.lastname: Kang
authors.forename: Xiangao
authors.initials: X
authors.lastname: Sun
authors.forename: Harry A
authors.initials: HA
authors.lastname: Rogoff
authors.forename: Changill
authors.initials: C
authors.lastname: Ban
authors.forename: Soyoun
authors.initials: S
authors.lastname: Kim
authors.forename: Chiang J
authors.initials: CJ
authors.lastname: Li
authors.forename: Dong-Ki
authors.initials: DK
authors.lastname: Lee
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D005434:Flow Cytometry; D020868:Gene Silencing; D006801:Humans; D034741:RNA, Small Interfering / Q000737:chemistry*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D034741:RNA, Small Interfering