title: Nuclear retention of unspliced mRNAs in yeast is mediated by perinuclear Mlp1.
abstract: The molecular mechanism underlying the retention of intron-containing mRNAs in the nucleus is not understood. Here, we show that retention of intron-containing mRNAs in yeast is mediated by perinuclearly located Mlp1. Deletion of MLP1 impairs retention while having no effect on mRNA splicing. The Mlp1-dependent leakage of intron-containing RNAs is increased in presence of ts-prp18 delta, a splicing mutant. When overall pre-mRNA levels are increased by deletion of RRP6, a nuclear exosome component, MLP1 deletion augments leakage of only the intron-containing portion of mRNAs. Our data suggest, moreover, that Mlp1-dependent retention is mediated via the 5' splice site. Intriguingly, we found Mlp-proteins to be present only on sections of the NE adjacent to chromatin. We propose that at this confined site the perinuclear Mlp1 implements a quality control step prior to export, physically retaining faulty pre-mRNAs.
authors.affiliation: Unité de Biologie Cellulaire du Noyau, CNRS URA 2582, Institut Pasteur, 25 rue du Docteur Roux, 75724 Paris Cedex 15, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Galy
authors.forename: Olivier
authors.initials: O
authors.lastname: Gadal
authors.forename: Micheline
authors.initials: M
authors.lastname: Fromont-Racine
authors.forename: Alper
authors.initials: A
authors.lastname: Romano
authors.forename: Alain
authors.initials: A
authors.lastname: Jacquier
authors.forename: Ulf
authors.initials: U
authors.lastname: Nehrbass
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics* / Q000378:metabolism; D005095:Exoribonucleases / Q000172:deficiency / Q000235:genetics; D063326:Exosome Multienzyme Ribonuclease Complex; D007438:Introns / Q000235:genetics; D009154:Mutation / Q000235:genetics; D009685:Nuclear Envelope / Q000235:genetics / Q000378:metabolism; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D021381:Protein Transport / Q000235:genetics; D022821:RNA Splice Sites / Q000235:genetics; D012326:RNA Splicing / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins; D017415:Ribonucleoprotein, U5 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D015003:Yeasts / Q000235:genetics* / Q000378:metabolism
chemical_list: C080988:MLP1 protein, S cerevisiae; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins; C080779:PRP18 protein, S cerevisiae; D022821:RNA Splice Sites; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D017415:Ribonucleoprotein, U5 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins; D005095:Exoribonucleases; D063326:Exosome Multienzyme Ribonuclease Complex; C112610:RRP6 protein, S cerevisiae