title: Mammalian introns: when the junk generates molecular diversity.
abstract: Introns represent almost half of the human genome, yet their vast majority is eliminated from eukaryotic transcripts through RNA splicing. Nevertheless, they feature key elements and functions that deserve further interest. At the level of DNA, introns are genomic segments that can shelter independent transcription units for coding and non-coding RNAs which transcription may interfere with that of the host gene, and regulatory elements that can influence gene expression and splicing itself. From the RNA perspective, some introns can be subjected to alternative splicing. Intron retention appear to provide some plasticity to the nature of the protein produced, its distribution in a given cell type and timing of its translation. Intron retention may also serve as a switch to produce coding or non-coding RNAs from the same transcription unit. Conversely, splicing of introns has been directly implicated in the production of small regulatory RNAs. Hence, splicing of introns also appears to provide plasticity to the type of RNA produced from a genetic locus (coding, non-coding, short or long). We addressed these aspects to add to our understanding of mechanisms that control the fate of introns and could be instrumental in regulating genomic output and hence cell fate.
authors.affiliation: CNRS UMR7216, Epigenetics and Cell Fate, Université Paris Diderot, Sorbonne Paris Cité, UMR7216 Epigénétique et Destin Cellulaire, Bâtiment Lamarck B, Case Courrier 7042, 35 rue Hélène Brion, 75013 Paris, France. florent.hube@univ-paris-diderot.fr.
authors.forename: Florent
authors.initials: F
authors.lastname: Hubé
authors.affiliation: CNRS UMR7216, Epigenetics and Cell Fate, Université Paris Diderot, Sorbonne Paris Cité, UMR7216 Epigénétique et Destin Cellulaire, Bâtiment Lamarck B, Case Courrier 7042, 35 rue Hélène Brion, 75013 Paris, France. claire.francastel@univ-paris-diderot.fr.
authors.forename: Claire
authors.initials: C
authors.lastname: Francastel
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D005091:Exons / Q000235:genetics; D005786:Gene Expression Regulation; D014644:Genetic Variation; D016678:Genome / Q000235:genetics*; D006801:Humans; D007438:Introns / Q000235:genetics*; D008957:Models, Genetic; D012333:RNA, Messenger / Q000235:genetics*
chemical_list: D012333:RNA, Messenger