title: The RNA helicase DDX5/p68 is a key factor promoting c-fos expression at different levels from transcription to mRNA export.
abstract: It is widely accepted that pre-mRNA maturation, including splicing, is tightly coupled to both transcription and mRNA export, but factors linking the three processes are less understood. By analysing the estrogen-regulated expression of the c-fos mRNA that is processed during transcription, we show that the ddx5 RNA helicase, is required throughout the major nuclear steps of the expression of the c-fos gene, from transcription to mRNA export. Indeed, ddx5, whose recruitment on the c-fos gene was increased upon estrogen treatment, was required for the full transcriptional activation of the c-fos gene. In addition, ddx5 was required for c-fos co-transcriptional RNA splicing. When splicing occurred post-transcriptionally in the absence of ddx5, the c-fos mRNA was poorly exported into the cytosol because of inefficient recruitment of the TAP mRNA export receptor. Finally, ddx5 was present in the c-fos messenger ribonucleoprotein together with mRNA export factors, which further supports that ddx5 is a key operator in the c-fos 'mRNA factory'.
authors.affiliation: Université de Lyon, Inserm U1052, CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, Centre Léon Bérard, 28 Rue Laennec, F-69008 Lyon, France.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Zonta
authors.forename: Danielle
authors.initials: D
authors.lastname: Bittencourt
authors.forename: Samaan
authors.initials: S
authors.lastname: Samaan
authors.forename: Sophie
authors.initials: S
authors.lastname: Germann
authors.forename: Martin
authors.initials: M
authors.lastname: Dutertre
authors.forename: Didier
authors.initials: D
authors.lastname: Auboeuf
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D053487:DEAD-box RNA Helicases / Q000502:physiology*; D004958:Estradiol / Q000494:pharmacology; D006801:Humans; D061986:MCF-7 Cells; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D012326:RNA Splicing; D034443:RNA Transport; D012333:RNA, Messenger / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D012261:Ribonucleoproteins; C026452:messenger ribonucleoprotein; D004958:Estradiol; C506749:Ddx5 protein, human; D053487:DEAD-box RNA Helicases