title: Endogenous Multiple Exon Skipping and Back-Splicing at the DMD Mutation Hotspot.
abstract: Duchenne muscular dystrophy (DMD) is a severe muscular disorder. It was reported that multiple exon skipping (MES), targeting exon 45-55 of theDMDgene, might improve patients' symptoms because patients who have a genomic deletion of all these exons showed very mild symptoms. Thus, exon 45-55 skipping treatments for DMD have been proposed as a potential clinical cure. Herein, we detected the expression of endogenous exons 44-56 connected mRNA transcript of theDMDusing total RNAs derived from human normal skeletal muscle by reverse transcription polymerase chain reaction (RT-PCR), and identified a total of eight types of MES products around the hotspot. Surprisingly, the 5' splice sites of recently reported post-transcriptional introns (remaining introns after co-transcriptional splicing) act as splicing donor sites for MESs. We also tested exon combinations to generateDMDcircular RNAs (circRNAs) and determined the preferential splice sites of back-splicing, which are involved not only in circRNA generation, but also in MESs. Our results fit the current circRNA-generation model, suggesting that upstream post-transcriptional introns trigger MES and generate circRNA because its existence is critical for the intra-intronic interaction or for extremely distal splicing.
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology, Nomi, Ishikawa 923-1292, Japan. suzuki-h@jaist.ac.jp.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo 187-8502, Japan. tsugu56@ncnp.go.jp.
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Aoki
authors.affiliation: Division of Gene Expression Mechanism, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi 470-1192, Japan. tkame@fujita-hu.ac.jp.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Kameyama
authors.affiliation: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo 187-8502, Japan. tksaito@ncnp.go.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Saito
authors.affiliation: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo 187-8502, Japan. masuda@ncnp.go.jp.
authors.forename: Satoru
authors.initials: S
authors.lastname: Masuda
authors.affiliation: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo 187-8502, Japan. tanihata@ncnp.go.jp.
authors.forename: Jun
authors.initials: J
authors.lastname: Tanihata
authors.affiliation: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo 187-8502, Japan. t-naga.nuro@tmd.ac.jp.|Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Bunkyoku, Tokyo 113-0034, Japan. t-naga.nuro@tmd.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Nagata
authors.affiliation: Division of Gene Expression Mechanism, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi 470-1192, Japan. mayeda@fujita-hu.ac.jp.
authors.forename: Akila
authors.initials: A
authors.lastname: Mayeda
authors.affiliation: Department of Molecular Therapy, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Kodaira, Tokyo 187-8502, Japan. takeda@ncnp.go.jp.
authors.forename: Shin'ichi
authors.initials: S
authors.lastname: Takeda
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology, Nomi, Ishikawa 923-1292, Japan. tukahara@jaist.ac.jp.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Tsukahara
mesh_terms: D016189:Dystrophin / Q000235:genetics*; D005091:Exons; D015870:Gene Expression; D006801:Humans; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics*; D009154:Mutation; D012322:RNA Precursors / Q000235:genetics*; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: C484258:DMD protein, human; D016189:Dystrophin; D012322:RNA Precursors; D012333:RNA, Messenger
keywords: DMD; circular RNA; multiple exon skipping; pre-mRNA splicing