title: Altered RNA processing and export lead to retention of mRNAs near transcription sites and nuclear pore complexes or within the nucleolus.
abstract: Many protein factors are required for mRNA biogenesis and nuclear export, which are central to the eukaryotic gene expression program. It is unclear, however, whether all factors have been identified. Here we report on a screen of >1000 essential gene mutants in Saccharomyces cerevisiae for defects in mRNA processing and export, identifying 26 mutants with defects in this process. Single-molecule FISH data showed that the majority of these mutants accumulated mRNA within specific regions of the nucleus, which included 1) mRNAs within the nucleolus when nucleocytoplasmic transport, rRNA biogenesis, or RNA processing and surveillance was disrupted, 2) the buildup of mRNAs near transcription sites in 3'-end processing and chromosome segregation mutants, and 3) transcripts being enriched near nuclear pore complexes when components of the mRNA export machinery were mutated. These data show that alterations to various nuclear processes lead to the retention of mRNAs at discrete locations within the nucleus.
authors.affiliation: Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2H7, Canada.
authors.forename: Biplab
authors.initials: B
authors.lastname: Paul
authors.affiliation: Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2H7, Canada ben.montpetit@ualberta.ca.
authors.forename: Ben
authors.initials: B
authors.lastname: Montpetit
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000502:physiology; D002466:Cell Nucleolus / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D022022:Nuclear Pore / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D034443:RNA Transport / Q000502:physiology*; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D009687:Nuclear Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins