title: Mutation of siRNA results in thermodynamically unstable duplex which influences knockdown of dmrt1 by RNA interference.
abstract: MicroRNAs (miRNAs) constitute a growing class of non-coding RNAs that are thought to regulate gene expression by translational repression and mRNA degradation. We report here that short interfering RNA (siRNA) mutation significantly changed kinetics of the folding and unfolding of secondary structures and decreased Tm value of the duplex melting. The mutant duplex was more unstable thermodynamically than the normal structure. Furthermore negative effects of the mutation on RNA interference (RNAi) was observed in both mouse dmrt1 transfected COS-7 and Sertoli cells in which endogenous dmrt1 was expressed. However, interference efficiency of mutational and normal duplex in Sertoli cells was not significant in comparison with those in dmrt1 transfected COS-7 cells, suggesting complex regulatory mechanisms in RNAi in endogenous dmrt1 expression. Abundance of intronic miRNA structures observed in the dmrt1 gene may also contribute to the precise regulation cascade in the dmrt1 expression. These findings help in further understanding RNA silence in vertebrate development and drug design for target gene.
authors.affiliation: Department of Genetics, Center for Developmental Biology, College of Life Sciences, Wuhan University, Wuhan 430072, P.R. China.
authors.forename: Kai
authors.initials: K
authors.lastname: Yao
authors.forename: Heng
authors.initials: H
authors.lastname: Lu
authors.forename: Hanhua
authors.initials: H
authors.lastname: Cheng
authors.forename: Rongjia
authors.initials: R
authors.lastname: Zhou
mesh_terms: D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D015536:Down-Regulation; D007700:Kinetics; D008297:Male; D051379:Mice; D035683:MicroRNAs; D017510:Protein Folding; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012708:Sertoli Cells; D013696:Temperature; D014157:Transcription Factors / Q000096:biosynthesis* / Q000737:chemistry*; D014162:Transfection
chemical_list: C110547:DMRT1 protein; D035683:MicroRNAs; D034741:RNA, Small Interfering; D014157:Transcription Factors