title: How slow RNA polymerase II elongation favors alternative exon skipping.
abstract: Splicing is functionally coupled to transcription, linking the rate of RNA polymerase II (Pol II) elongation and the ability of splicing factors to recognize splice sites (ss) of various strengths. In most cases, slow Pol II elongation allows weak splice sites to be recognized, leading to higher inclusion of alternative exons. Using CFTR alternative exon 9 (E9) as a model, we show here that slowing down elongation can also cause exon skipping by promoting the recruitment of the negative factor ETR-3 onto the UG-repeat at E9 3' splice site, which displaces the constitutive splicing factor U2AF65 from the overlapping polypyrimidine tract. Weakening of E9 5' ss increases ETR-3 binding at the 3' ss and subsequent E9 skipping, whereas strengthening of the 5' ss usage has the opposite effect. This indicates that a delay in the cotranscriptional emergence of the 5' ss promotes ETR-3 recruitment and subsequent inhibition of E9 inclusion.
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina; Inserm U1078-ECLA Team, Faculty of Medicine, 22 Avenue Camille Desmoulins, 29238 Brest Cedex 3, France.
authors.forename: Gwendal
authors.initials: G
authors.lastname: Dujardin
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina.
authors.forename: Celina
authors.initials: C
authors.lastname: Lafaille
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina.
authors.forename: Manuel
authors.initials: M
authors.lastname: de la Mata
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina.
authors.forename: Luciano E
authors.initials: LE
authors.lastname: Marasco
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina.
authors.forename: Manuel J
authors.initials: MJ
authors.lastname: Muñoz
authors.affiliation: Inserm U1078-ECLA Team, Faculty of Medicine, 22 Avenue Camille Desmoulins, 29238 Brest Cedex 3, France.
authors.forename: Catherine
authors.initials: C
authors.lastname: Le Jossic-Corcos
authors.affiliation: Inserm U1078-ECLA Team, Faculty of Medicine, 22 Avenue Camille Desmoulins, 29238 Brest Cedex 3, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Corcos
authors.affiliation: Laboratorio de Fisiología y Biología Molecular, Departamento de Fisiología, Biología Molecular y Celular, IFIBYNE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA Buenos Aires, Argentina. Electronic address: ark@fbmc.fcen.uba.ar.
authors.forename: Alberto R
authors.initials: AR
authors.lastname: Kornblihtt
mesh_terms: D017398:Alternative Splicing; D001665:Binding Sites; D000067878:CELF Proteins; D018938:Caco-2 Cells; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics* / Q000378:metabolism; D005091:Exons; D057809:HEK293 Cells; D006801:Humans; D008957:Models, Genetic; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D012319:RNA Polymerase II / Q000378:metabolism*; D022821:RNA Splice Sites / Q000502:physiology*; D016601:RNA-Binding Proteins / Q000378:metabolism; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D000072668:Splicing Factor U2AF; D014158:Transcription, Genetic
chemical_list: D000067878:CELF Proteins; C117363:CELF2 protein, human; C505032:CFTR protein, human; D009419:Nerve Tissue Proteins; D009687:Nuclear Proteins; D022821:RNA Splice Sites; D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins; D000072668:Splicing Factor U2AF; C000607494:U2AF2 protein, human; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D012319:RNA Polymerase II