title: Myotonic dystrophy, when simple repeats reveal complex pathogenic entities: new findings and future challenges.
abstract: Expanded, non-coding RNAs can exhibit a deleterious gain-of-function causing human disease through abnormal interactions with RNA-binding proteins. Myotonic dystrophy (DM), the prototypical example of an RNA-dominant disorder, is mediated by trinucleotide repeat-containing transcripts that deregulate alternative splicing. Spliceopathy has therefore been a major focus of DM research. However, changes in gene expression, protein translation and micro-RNA metabolism may also contribute to disease pathology. The exciting finding of bidirectional transcription and non-conventional RNA translation of trinucleotide repeat sequences points to a new scenario, in which DM is not mediated by one single expanded RNA transcript, but involves multiple pathogenic elements and pathways. The study of the growing number of human diseases associated with toxic repeat-containing transcripts provides important insight into the understanding of the complex pathways of RNA toxicity. This review describes some of the recent advances in the understanding of the molecular mechanisms behind DM and other RNA-dominant disorders.
authors.affiliation: INSERM U781, Université Paris Descartes, Hôpital Necker Enfants Malades, 156 rue de Vaugirard, Paris Cedex 15, France.
authors.forename: Géraldine
authors.initials: G
authors.lastname: Sicot
authors.forename: Geneviève
authors.initials: G
authors.lastname: Gourdon
authors.forename: Mário
authors.initials: M
authors.lastname: Gomes-Pereira
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D005786:Gene Expression Regulation; D006801:Humans; D009223:Myotonic Dystrophy / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D014176:Protein Biosynthesis; D019680:Trinucleotide Repeat Expansion; D018911:Trinucleotide Repeats