1
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Asada R, Dominguez A, Montpetit B. Single-molecule quantitation of RNA-binding protein occupancy and stoichiometry defines a role for Yra1 (Aly/REF) in nuclear mRNP organization. Cell Rep 2023; 42:113415. [PMID: 37963019 PMCID: PMC10841842 DOI: 10.1016/j.celrep.2023.113415] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 10/09/2023] [Accepted: 10/25/2023] [Indexed: 11/16/2023] Open
Abstract
RNA-binding proteins (RBPs) interact with mRNA to form supramolecular complexes called messenger ribonucleoprotein (mRNP) particles. These dynamic assemblies direct and regulate individual steps of gene expression; however, their composition and functional importance remain largely unknown. Here, we develop a total internal reflection fluorescence-based single-molecule imaging assay to investigate stoichiometry and co-occupancy of 15 RBPs within mRNPs from Saccharomyces cerevisiae. We show compositional heterogeneity of single mRNPs and plasticity across different growth conditions, with major co-occupants of mRNPs containing the nuclear cap-binding complex identified as Yra1 (1-10 copies), Nab2 (1-6 copies), and Npl3 (1-6 copies). Multicopy Yra1-bound mRNPs are specifically co-occupied by the THO complex and assembled on mRNAs biased by transcript length and RNA secondary structure. Yra1 depletion results in decreased compaction of nuclear mRNPs demonstrating a packaging function. Together, we provide a quantitative framework for gene- and condition-dependent RBP occupancy and stoichiometry in individual nuclear mRNPs.
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Affiliation(s)
- Ryuta Asada
- Department of Viticulture and Enology, University of California, Davis, Davis, CA 95616, USA
| | - Andrew Dominguez
- Department of Viticulture and Enology, University of California, Davis, Davis, CA 95616, USA; Biochemistry, Molecular, Cellular, and Developmental Biology Graduate Group, University of California, Davis, Davis, CA 95616, USA
| | - Ben Montpetit
- Department of Viticulture and Enology, University of California, Davis, Davis, CA 95616, USA; Biochemistry, Molecular, Cellular, and Developmental Biology Graduate Group, University of California, Davis, Davis, CA 95616, USA.
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2
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Bensidoun P, Zenklusen D, Oeffinger M. Differential affinity purification and mass spectrometry analysis of two nuclear pore complex isoforms in yeast S. cerevisiae. STAR Protoc 2023; 4:102359. [PMID: 37327111 PMCID: PMC10300402 DOI: 10.1016/j.xpro.2023.102359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/03/2023] [Accepted: 05/16/2023] [Indexed: 06/18/2023] Open
Abstract
Two isoforms of the nuclear pore complex (NPC) have been identified in the yeast S. cerevisiae, which coexist at the periphery of the nucleus and differ by the presence or absence of a nuclear basket. Here, we present a protocol to isolate the two types of NPCs from the same cell extract and dissect their interactomes. We describe steps for powder preparation and magnetic bead conjunction and detail differential affinity purification and outcome evaluation through SDS-PAGE, silver staining, and mass spectrometry analysis. For complete details on the use and execution of this protocol, please refer to Bensidoun et al.1.
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Affiliation(s)
- Pierre Bensidoun
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, QC H2W 1R7, Canada; Département de Biochimie et Médecine Moléculaire, Faculté de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Daniel Zenklusen
- Département de Biochimie et Médecine Moléculaire, Faculté de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada.
| | - Marlene Oeffinger
- Institut de Recherches Cliniques de Montréal, 110 Avenue des Pins Ouest, Montréal, QC H2W 1R7, Canada; Département de Biochimie et Médecine Moléculaire, Faculté de Médecine, Université de Montréal, Montréal, QC H3T 1J4, Canada; Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC H3A 1A3, Canada.
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3
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Kwiatek L, Landry-Voyer AM, Latour M, Yague-Sanz C, Bachand F. PABPN1 prevents the nuclear export of an unspliced RNA with a constitutive transport element and controls human gene expression via intron retention. RNA (NEW YORK, N.Y.) 2023; 29:644-662. [PMID: 36754576 PMCID: PMC10158996 DOI: 10.1261/rna.079294.122] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 01/12/2023] [Indexed: 05/06/2023]
Abstract
Intron retention is a type of alternative splicing where one or more introns remain unspliced in a polyadenylated transcript. Although many viral systems are known to translate proteins from mRNAs with retained introns, restriction mechanisms generally prevent export and translation of incompletely spliced mRNAs. Here, we provide evidence that the human nuclear poly(A)-binding protein, PABPN1, functions in such restrictions. Using a reporter construct in which nuclear export of an incompletely spliced mRNA is enhanced by a viral constitutive transport element (CTE), we show that PABPN1 depletion results in a significant increase in export and translation from the unspliced CTE-containing transcript. Unexpectedly, we find that inactivation of poly(A)-tail exosome targeting by depletion of PAXT components had no effect on export and translation of the unspliced reporter mRNA, suggesting a mechanism largely independent of nuclear RNA decay. Interestingly, a PABPN1 mutant selectively defective in stimulating poly(A) polymerase elongation strongly enhanced the expression of the unspliced, but not of intronless, reporter transcripts. Analysis of RNA-seq data also revealed that PABPN1 controls the expression of many human genes via intron retention. Notably, PABPN1-dependent intron retention events mostly affected 3'-terminal introns and were insensitive to PAXT and NEXT deficiencies. Our findings thus disclose a role for PABPN1 in restricting nuclear export of intron-retained transcripts and reinforce the interdependence between terminal intron splicing, 3' end processing, and polyadenylation.
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Affiliation(s)
- Lauren Kwiatek
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, Québec, Canada J1E 4K8
| | - Anne-Marie Landry-Voyer
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, Québec, Canada J1E 4K8
| | - Mélodie Latour
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, Québec, Canada J1E 4K8
| | - Carlo Yague-Sanz
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, Québec, Canada J1E 4K8
| | - Francois Bachand
- RNA Group, Department of Biochemistry and Functional Genomics, Université de Sherbrooke, Sherbrooke, Québec, Canada J1E 4K8
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4
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Hashimoto H, Ramirez DH, Lautier O, Pawlak N, Blobel G, Palancade B, Debler EW. Structure of the pre-mRNA leakage 39-kDa protein reveals a single domain of integrated zf-C3HC and Rsm1 modules. Sci Rep 2022; 12:17691. [PMID: 36271106 PMCID: PMC9586977 DOI: 10.1038/s41598-022-22183-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 10/11/2022] [Indexed: 01/18/2023] Open
Abstract
In Saccharomyces cerevisiae, the pre-mRNA leakage 39-kDa protein (ScPml39) was reported to retain unspliced pre-mRNA prior to export through nuclear pore complexes (NPCs). Pml39 homologs outside the Saccharomycetaceae family are currently unknown, and mechanistic insight into Pml39 function is lacking. Here we determined the crystal structure of ScPml39 at 2.5 Å resolution to facilitate the discovery of orthologs beyond Saccharomycetaceae, e.g. in Schizosaccharomyces pombe or human. The crystal structure revealed integrated zf-C3HC and Rsm1 modules, which are tightly associated through a hydrophobic interface to form a single domain. Both zf-C3HC and Rsm1 modules belong to the Zn-containing BIR (Baculovirus IAP repeat)-like super family, with key residues of the canonical BIR domain being conserved. Features unique to the Pml39 modules refer to the spacing between the Zn-coordinating residues, giving rise to a substantially tilted helix αC in the zf-C3HC and Rsm1 modules, and an extra helix αAB' in the Rsm1 module. Conservation of key residues responsible for its distinct features identifies S. pombe Rsm1 and Homo sapiens NIPA/ZC3HC1 as structural orthologs of ScPml39. Based on the recent functional characterization of NIPA/ZC3HC1 as a scaffold protein that stabilizes the nuclear basket of the NPC, our data suggest an analogous function of ScPml39 in S. cerevisiae.
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Affiliation(s)
- Hideharu Hashimoto
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, 19107, USA
| | - Daniel H Ramirez
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Ophélie Lautier
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France
| | - Natalie Pawlak
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Günter Blobel
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA
| | - Benoît Palancade
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France.
| | - Erik W Debler
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, 19107, USA.
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, 10065, USA.
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5
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Bensidoun P, Reiter T, Montpetit B, Zenklusen D, Oeffinger M. Nuclear mRNA metabolism drives selective basket assembly on a subset of nuclear pore complexes in budding yeast. Mol Cell 2022; 82:3856-3871.e6. [PMID: 36220102 PMCID: PMC10300651 DOI: 10.1016/j.molcel.2022.09.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 06/24/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022]
Abstract
To determine which transcripts should reach the cytoplasm for translation, eukaryotic cells have established mechanisms to regulate selective mRNA export through the nuclear pore complex (NPC). The nuclear basket, a substructure of the NPC protruding into the nucleoplasm, is thought to function as a stable platform where mRNA-protein complexes (mRNPs) are rearranged and undergo quality control prior to export, ensuring that only mature mRNAs reach the cytoplasm. Here, we use proteomic, genetic, live-cell, and single-molecule resolution microscopy approaches in budding yeast to demonstrate that basket formation is dependent on RNA polymerase II transcription and subsequent mRNP processing. We further show that while all NPCs can bind Mlp1, baskets assemble only on a subset of nucleoplasmic NPCs, and these basket-containing NPCs associate a distinct protein and RNA interactome. Taken together, our data point toward NPC heterogeneity and an RNA-dependent mechanism for functionalization of NPCs in budding yeast through nuclear basket assembly.
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Affiliation(s)
- Pierre Bensidoun
- Institut de recherches cliniques de Montréal (IRCM), Montréal, QC, Canada; Département de biochimie et médecine moléculaire, Université de Montréal, Montréal, QC, Canada
| | - Taylor Reiter
- Department of Viticulture and Enology, University of California, Davis, Davis, CA, USA
| | - Ben Montpetit
- Department of Viticulture and Enology, University of California, Davis, Davis, CA, USA
| | - Daniel Zenklusen
- Département de biochimie et médecine moléculaire, Université de Montréal, Montréal, QC, Canada.
| | - Marlene Oeffinger
- Institut de recherches cliniques de Montréal (IRCM), Montréal, QC, Canada; Département de biochimie et médecine moléculaire, Université de Montréal, Montréal, QC, Canada; Division of Experimental Medicine, McGill University, Montréal, QC, Canada.
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6
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Meinema AC, Marzelliusardottir A, Mirkovic M, Aspert T, Lee SS, Charvin G, Barral Y. DNA circles promote yeast ageing in part through stimulating the reorganization of nuclear pore complexes. eLife 2022; 11:71196. [PMID: 35373738 PMCID: PMC9020822 DOI: 10.7554/elife.71196] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 04/03/2022] [Indexed: 11/13/2022] Open
Abstract
The nuclear pore complex (NPC) mediates nearly all exchanges between nucleus and cytoplasm, and in many species it changes composition as the organism ages. However, how these changes arise and whether they contribute themselves to ageing is poorly understood. We show that SAGA-dependent attachment of DNA circles to NPCs in replicatively ageing yeast cells causes NPCs to lose their nuclear basket and cytoplasmic complexes. These NPCs were not recognized as defective by the NPC quality control machinery (SINC) and not targeted by ESCRTs. They interacted normally or more effectively with protein import and export factors but specifically lost mRNA export factors. Acetylation of Nup60 drove the displacement of basket and cytoplasmic complexes from circle-bound NPCs. Mutations preventing this remodeling extended the replicative lifespan of the cells. Thus, our data suggest that the anchorage of accumulating circles locks NPCs in a specialized state and that this process is intrinsically linked to the mechanisms by which ERCs promote ageing.
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Affiliation(s)
| | | | | | - Théo Aspert
- Department of Developmental Biology and Stem Cells, Institute of Genetics and Molecular and Cellular Biology, Illkirch, France
| | - Sung Sik Lee
- Department of Biology, ETH Zürich, Zürich, Switzerland
| | - Gilles Charvin
- Department of Developmental Biology and Stem Cells, Institute of Genetics and Molecular and Cellular Biology, Illkirch, France
| | - Yves Barral
- Department of Biology, ETH Zürich, Zürich, Switzerland
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7
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Dargemont C. Analysis of Ubiquitylation and SUMOylation of Yeast Nuclear Pore Complex Proteins. Methods Mol Biol 2022; 2502:259-269. [PMID: 35412244 DOI: 10.1007/978-1-0716-2337-4_17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Posttranslational modifications and in particular ubiquitylation and SUMOylation of the nuclear pore complex (NPC), have been shown to regulate some of its functions, particularly in response to diverse stress signals.Although proteomic approaches are extremely powerful to identify substrates and modification sites, dissecting specific mechanisms and regulation functions of ubiquitylation and SUMOylation of the diverse NPC proteins, in different genetic backgrounds or cell environmental conditions, requires specific biochemical assays based on purification and precise analysis of 6His-tagged ubiquitylated or SUMOylated protein of interest. Here we describe an approach that can be easily employed without specific equipment. It allowed to successfully analyze yeast NPC proteins but can easily be adapted to the study of the mammalian NPC.
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Affiliation(s)
- Catherine Dargemont
- Institut de Génétique Humaine, Université de Montpellier, Laboratoire de Virologie Moléculaire CNRS-UMR9002, Montpellier, France.
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8
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Bonnet A, Chaput C, Palmic N, Palancade B, Lesage P. A nuclear pore sub-complex restricts the propagation of Ty retrotransposons by limiting their transcription. PLoS Genet 2021; 17:e1009889. [PMID: 34723966 PMCID: PMC8585004 DOI: 10.1371/journal.pgen.1009889] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 11/11/2021] [Accepted: 10/18/2021] [Indexed: 11/19/2022] Open
Abstract
Beyond their canonical function in nucleocytoplasmic exchanges, nuclear pore complexes (NPCs) regulate the expression of protein-coding genes. Here, we have implemented transcriptomic and molecular methods to specifically address the impact of the NPC on retroelements, which are present in multiple copies in genomes. We report a novel function for the Nup84 complex, a core NPC building block, in specifically restricting the transcription of LTR-retrotransposons in yeast. Nup84 complex-dependent repression impacts both Copia and Gypsy Ty LTR-retrotransposons, all over the S. cerevisiae genome. Mechanistically, the Nup84 complex restricts the transcription of Ty1, the most active yeast retrotransposon, through the tethering of the SUMO-deconjugating enzyme Ulp1 to NPCs. Strikingly, the modest accumulation of Ty1 RNAs caused by Nup84 complex loss-of-function is sufficient to trigger an important increase of Ty1 cDNA levels, resulting in massive Ty1 retrotransposition. Altogether, our study expands our understanding of the complex interactions between retrotransposons and the NPC, and highlights the importance for the cells to keep retrotransposons under tight transcriptional control.
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Affiliation(s)
- Amandine Bonnet
- Université de Paris, Institut de Recherche Saint-Louis, INSERM U944, CNRS UMR 7212, Paris, France
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France
| | - Carole Chaput
- Université de Paris, Institut de Recherche Saint-Louis, INSERM U944, CNRS UMR 7212, Paris, France
| | - Noé Palmic
- Université de Paris, Institut de Recherche Saint-Louis, INSERM U944, CNRS UMR 7212, Paris, France
| | - Benoit Palancade
- Université de Paris, CNRS, Institut Jacques Monod, Paris, France
| | - Pascale Lesage
- Université de Paris, Institut de Recherche Saint-Louis, INSERM U944, CNRS UMR 7212, Paris, France
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9
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Wang R, Huang A, Wang Y, Mei P, Zhu H, Chen Q, Xu S. High-Resolution Microscopy to Learn the Nuclear Organization of the Living Yeast Cells. Stem Cells Int 2021; 2021:9951114. [PMID: 34497652 PMCID: PMC8421178 DOI: 10.1155/2021/9951114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 08/07/2021] [Indexed: 11/18/2022] Open
Abstract
The spatial organization of the nucleus is a key determinant in all genome activities. However, the accurate measurement of the nuclear organization is still technically challenging. Here, the technology NucQuant we created previously was utilized to detect the variation of the nuclear organization, including the heterogeneity of the nuclear geometry, the change of the NPC distribution along different cell cycle stages during interphase, and the organization of the nucleolus. The results confirmed that not only the growth rate and the NPC distribution are influenced by the carbon source; the nuclear shape is also impacted by the carbon source. The nuclei lost their spherical geometry gradually when the cell was cultured from the most to a less favorable carbon source. We also discovered that the nucleolus prefers to locate at the nuclear periphery, which was called the "genes poor region," especially when the cells entered quiescence. Furthermore, the distribution of the NPC along the different stages during the interphase was analyzed. We proposed that with the growth of the cell, the nucleus would grow from the surface of the NE flanking the nucleolus firstly.
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Affiliation(s)
- Renjie Wang
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
| | - Aiwen Huang
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
| | - Yan Wang
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
| | - Pengxin Mei
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
| | - He Zhu
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
| | - Qianqian Chen
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
| | - Sankui Xu
- College of Materials Science & Engineering, Henan University of Technology, Zhengzhou, China
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10
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Bensidoun P, Zenklusen D, Oeffinger M. Choosing the right exit: How functional plasticity of the nuclear pore drives selective and efficient mRNA export. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 12:e1660. [PMID: 33938148 DOI: 10.1002/wrna.1660] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/30/2021] [Accepted: 04/04/2021] [Indexed: 12/17/2022]
Abstract
The nuclear pore complex (NPC) serves as a central gate for mRNAs to transit from the nucleus to the cytoplasm. The ability for mRNAs to get exported is linked to various upstream nuclear processes including co-transcriptional RNP assembly and processing, and only export competent mRNPs are thought to get access to the NPC. While the nuclear pore is generally viewed as a monolithic structure that serves as a mediator of transport driven by transport receptors, more recent evidence suggests that the NPC might be more heterogenous than previously believed, both in its composition or in the selective treatment of cargo that seek access to the pore, providing functional plasticity to mRNA export. In this review, we consider the interconnected processes of nuclear mRNA metabolism that contribute and mediate export competence. Furthermore, we examine different aspects of NPC heterogeneity, including the role of the nuclear basket and its associated complexes in regulating selective and/or efficient binding to and transport through the pore. This article is categorized under: RNA Export and Localization > Nuclear Export/Import RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Pierre Bensidoun
- Systems Biology, Institut de Recherches Cliniques de Montréal, Montréal, Canada.,Département de Biochimie et Médecine Moléculaire, Faculté de médecine, Université de Montréal, Montréal, Canada
| | - Daniel Zenklusen
- Département de Biochimie et Médecine Moléculaire, Faculté de médecine, Université de Montréal, Montréal, Canada
| | - Marlene Oeffinger
- Systems Biology, Institut de Recherches Cliniques de Montréal, Montréal, Canada.,Département de Biochimie et Médecine Moléculaire, Faculté de médecine, Université de Montréal, Montréal, Canada.,Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, Canada
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11
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Abstract
The HIV-1 Rev protein is a nuclear export factor for unspliced and incompletely spliced HIV-1 RNAs. Without Rev, these intron-retaining RNAs are trapped in the nucleus. A genome-wide screen identified nine proteins of the spliceosome, which all enhanced expression from the HIV-1 unspliced RNA after CRISPR/Cas knockdown. Depletion of DHX38, WDR70, and four proteins of the Prp19-associated complex (ISY1, BUD31, XAB2, and CRNKL1) resulted in a more than 20-fold enhancement of unspliced HIV-1 RNA levels in the cytoplasm. Targeting of CRNKL1, DHX38, and BUD31 affected nuclear export efficiencies of the HIV-1 unspliced RNA to a much larger extent than splicing. Transcriptomic analyses further revealed that CRNKL1 also suppresses cytoplasmic levels of a subset of cellular mRNAs, including some with selectively retained introns. Thus, CRNKL1-dependent nuclear retention is a novel cellular mechanism for the regulation of cytoplasmic levels of intron-retaining HIV-1 mRNAs, which HIV-1 may have harnessed to direct its complex splicing pattern.IMPORTANCE To regulate its complex splicing pattern, HIV-1 uses the adaptor protein Rev to shuttle unspliced or partially spliced mRNA from the nucleus to the cytoplasm. In the absence of Rev, these RNAs are retained in the nucleus, but it is unclear why. Here we identify cellular proteins whose depletion enhances cytoplasmic levels of the HIV-1 unspliced RNA. Depletion of one of them, CRNKL1, also increases cytoplasmic levels of a subset of intron-retaining cellular mRNA, suggesting that CRNKL1-dependent nuclear retention may be a basic cellular mechanism exploited by HIV-1.
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12
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Saik NO, Park N, Ptak C, Adames N, Aitchison JD, Wozniak RW. Recruitment of an Activated Gene to the Yeast Nuclear Pore Complex Requires Sumoylation. Front Genet 2020; 11:174. [PMID: 32211027 PMCID: PMC7067905 DOI: 10.3389/fgene.2020.00174] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 02/13/2020] [Indexed: 01/10/2023] Open
Abstract
In addition to their role in regulating transport across the nuclear envelope, increasing evidence suggests nuclear pore complexes (NPCs) function in regulating gene expression. For example, the induction of certain genes (e.g., yeast INO1) is accompanied by their movement from the nuclear interior to NPCs. As sumoylation has been linked to the regulation of chromatin spatial organization and transcriptional activity, we investigated the role of sumoylation in the expression and NPC recruitment of the INO1 gene. We observed that induction of INO1 is accompanied by both increased and decreased sumoylation of proteins associated with specific regions along the INO1 locus. Furthermore, we show that the E3 ligase Siz2/Nfi1 is required for targeting the INO1 locus to the NPC where it interacts with the SUMO isopeptidase Ulp1. Our data suggest that this interaction is required for both the association of INO1 with the NPC and for its normal expression. These results imply that sumoylation is a key regulator of INO1 targeting to the NPC, and a cycle of sumoylation and NPC-associated desumoylation events contribute to the regulation of INO1 expression.
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Affiliation(s)
- Natasha O Saik
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| | - Nogi Park
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada.,Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Starkville, MS, United States
| | - Christopher Ptak
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
| | - Neil Adames
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada.,New Culture, San Francisco, CA, United States
| | - John D Aitchison
- Seattle Children's Research Institute, Seattle, WA, United States
| | - Richard W Wozniak
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
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13
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Soheilypour M, Mofrad MRK. Quality control of mRNAs at the entry of the nuclear pore: Cooperation in a complex molecular system. Nucleus 2019; 9:202-211. [PMID: 29431587 PMCID: PMC5973141 DOI: 10.1080/19491034.2018.1439304] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Despite extensive research on how mRNAs are quality controlled prior to export into the cytoplasm, the exact underlying mechanisms are still under debate. Specifically, it is unclear how quality control proteins at the entry of the nuclear pore complex (NPC) distinguish normal and aberrant mRNAs. While some of the involved components are suggested to act as switches and recruit different factors to normal versus aberrant mRNAs, some experimental and computational evidence suggests that the combined effect of the regulated stochastic interactions between the involved components could potentially achieve an efficient quality control of mRNAs. In this review, we present a state-of-the-art portrait of the mRNA quality control research and discuss the current hypotheses proposed for dynamics of the cooperation between the involved components and how it leads to their shared goal: mRNA quality control prior to export into the cytoplasm.
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Affiliation(s)
- Mohammad Soheilypour
- a Molecular Cell Biomechanics Laboratory , Departments of Bioengineering and Mechanical Engineering, University of California , Berkeley
| | - Mohammad R K Mofrad
- a Molecular Cell Biomechanics Laboratory , Departments of Bioengineering and Mechanical Engineering, University of California , Berkeley
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14
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Toro-Ascuy D, Rojas-Araya B, García-de-Gracia F, Rojas-Fuentes C, Pereira-Montecinos C, Gaete-Argel A, Valiente-Echeverría F, Ohlmann T, Soto-Rifo R. A Rev-CBP80-eIF4AI complex drives Gag synthesis from the HIV-1 unspliced mRNA. Nucleic Acids Res 2019; 46:11539-11552. [PMID: 30239828 PMCID: PMC6265489 DOI: 10.1093/nar/gky851] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/12/2018] [Indexed: 12/15/2022] Open
Abstract
Gag synthesis from the full-length unspliced mRNA is critical for the production of the viral progeny during human immunodeficiency virus type-1 (HIV-1) replication. While most spliced mRNAs follow the canonical gene expression pathway in which the recruitment of the nuclear cap-binding complex (CBC) and the exon junction complex (EJC) largely stimulates the rates of nuclear export and translation, the unspliced mRNA relies on the viral protein Rev to reach the cytoplasm and recruit the host translational machinery. Here, we confirm that Rev ensures high levels of Gag synthesis by driving nuclear export and translation of the unspliced mRNA. These functions of Rev are supported by the CBC subunit CBP80, which binds Rev and the unspliced mRNA in the nucleus and the cytoplasm. We also demonstrate that Rev interacts with the DEAD-box RNA helicase eIF4AI, which translocates to the nucleus and cooperates with the viral protein to promote Gag synthesis. Finally, we show that the Rev/RRE axis is important for the assembly of a CBP80-eIF4AI complex onto the unspliced mRNA. Together, our results provide further evidence towards the understanding of the molecular mechanisms by which Rev drives Gag synthesis from the unspliced mRNA during HIV-1 replication.
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Affiliation(s)
- Daniela Toro-Ascuy
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Bárbara Rojas-Araya
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Francisco García-de-Gracia
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Cecilia Rojas-Fuentes
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Camila Pereira-Montecinos
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Aracelly Gaete-Argel
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Fernando Valiente-Echeverría
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - Théophile Ohlmann
- INSERM U1111, CIRI, Lyon F-69364, France.,Ecole Normale Supérieure de Lyon, Lyon F-69364, France
| | - Ricardo Soto-Rifo
- Laboratory of Molecular and Cellular Virology, Virology Program, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
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The mRNA export adaptor Yra1 contributes to DNA double-strand break repair through its C-box domain. PLoS One 2019; 14:e0206336. [PMID: 30951522 PMCID: PMC6450643 DOI: 10.1371/journal.pone.0206336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 03/24/2019] [Indexed: 11/30/2022] Open
Abstract
Yra1 is an mRNA export adaptor involved in mRNA biogenesis and export in S. cerevisiae. Yra1 overexpression was recently shown to promote accumulation of DNA:RNA hybrids favoring DNA double strand breaks (DSB), cell senescence and telomere shortening, via an unknown mechanism. Yra1 was also identified at an HO-induced DSB and Yra1 depletion causes defects in DSB repair. Previous work from our laboratory showed that Yra1 ubiquitination by Tom1 is important for mRNA export. Here, we found that Yra1 is also ubiquitinated by the SUMO-targeted ubiquitin ligases Slx5-Slx8 implicated in the interaction of irreparable DSB with nuclear pores. We further show that Yra1 binds an HO-induced irreparable DSB in a process dependent on resection. Importantly, a Yra1 mutant lacking the evolutionarily conserved C-box is not recruited to an HO-induced irreparable DSB and becomes lethal under DSB induction in a HO-cut reparable system. Together, the data provide evidence that Yra1 plays a crucial role in DSB repair via homologous recombination. While Yra1 sumoylation and/or ubiquitination are dispensable, the Yra1 C-box region is essential in this process.
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16
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Abstract
In eukaryotes, the separation of translation from transcription by the nuclear envelope enables mRNA modifications such as capping, splicing, and polyadenylation. These modifications are mediated by a spectrum of ribonuclear proteins that associate with preRNA transcripts, coordinating the different steps and coupling them to nuclear export, ensuring that only mature transcripts reach the cytoplasmic translation machinery. Although the components of this machinery have been identified and considerable functional insight has been achieved, a number of questions remain outstanding about mRNA nuclear export and how it is integrated into the nuclear phase of the gene expression pathway. Nuclear export factors mediate mRNA transit through nuclear pores to the cytoplasm, after which these factors are removed from the mRNA, preventing transcripts from returning to the nucleus. However, as outlined in this review, several aspects of the mechanism by which transport factor binding and release are mediated remain unclear, as are the roles of accessory nuclear components in these processes. Moreover, the mechanisms by which completion of mRNA splicing and polyadenylation are recognized, together with how they are coordinated with nuclear export, also remain only partially characterized. One attractive hypothesis is that dissociating poly(A) polymerase from the cleavage and polyadenylation machinery could signal completion of mRNA maturation and thereby provide a mechanism for initiating nuclear export. The impressive array of genetic, molecular, cellular, and structural data that has been generated about these systems now provides many of the tools needed to define the precise mechanisms involved in these processes and how they are integrated.
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Affiliation(s)
- Murray Stewart
- From the MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, United Kingdom
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17
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Fasken MB, Corbett AH, Stewart M. Structure-function relationships in the Nab2 polyadenosine-RNA binding Zn finger protein family. Protein Sci 2019; 28:513-523. [PMID: 30578643 PMCID: PMC6371209 DOI: 10.1002/pro.3565] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 12/15/2018] [Accepted: 12/17/2018] [Indexed: 12/12/2022]
Abstract
The poly(A) RNA binding Zn finger ribonucleoprotein Nab2 functions to control the length of 3' poly(A) tails in Saccharomyces cerevisiae as well as contributing to the integration of the nuclear export of mature mRNA with preceding steps in the nuclear phase of the gene expression pathway. Nab2 is constructed from an N-terminal PWI-fold domain, followed by QQQP and RGG motifs and then seven CCCH Zn fingers. The nuclear pore-associated proteins Gfd1 and Mlp1 bind to opposite sides of the Nab2 N-terminal domain and function in the nuclear export of mRNA, whereas the Zn fingers, especially fingers 5-7, bind to A-rich regions of mature transcripts and function to regulate poly(A) tail length as well as mRNA compaction prior to nuclear export. Nab2 Zn fingers 5-7 have a defined spatial arrangement, with fingers 5 and 7 arranged on one side of the cluster and finger 6 on the other side. This spatial arrangement facilitates the dimerization of Nab2 when bound to adenine-rich RNAs and regulates both the termination of 3' polyadenylation and transcript compaction. Nab2 also functions to coordinate steps in the nuclear phase of the gene expression pathway, such as splicing and polyadenylation, with the generation of mature mRNA and its nuclear export. Nab2 orthologues in higher Eukaryotes have similar domain structures and play roles associated with the regulation of splicing and polyadenylation. Importantly, mutations in the gene encoding the human Nab2 orthologue ZC3H14 and cause intellectual disability.
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Affiliation(s)
- Milo B Fasken
- Department of Biology, Emory University, Atlanta, Georgia 30322
| | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, Georgia 30322
| | - Murray Stewart
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, United Kingdom
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18
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A SUMO-dependent feedback loop senses and controls the biogenesis of nuclear pore subunits. Nat Commun 2018; 9:1665. [PMID: 29695777 PMCID: PMC5916902 DOI: 10.1038/s41467-018-03673-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 03/05/2018] [Indexed: 11/29/2022] Open
Abstract
While the activity of multiprotein complexes is crucial for cellular metabolism, little is known about the mechanisms that collectively control the expression of their components. Here, we investigate the regulations targeting the biogenesis of the nuclear pore complex (NPC), the macromolecular assembly mediating nucleocytoplasmic exchanges. Systematic analysis of RNA-binding proteins interactomes, together with in vivo and in vitro assays, reveal that a subset of NPC mRNAs are specifically bound by Hek2, a yeast hnRNP K-like protein. Hek2-dependent translational repression and protein turnover are further shown to finely tune the levels of NPC subunits. Strikingly, mutations or physiological perturbations altering pore integrity decrease the levels of the NPC-associated SUMO protease Ulp1, and trigger the accumulation of sumoylated versions of Hek2 unable to bind NPC mRNAs. Our results support the existence of a quality control mechanism involving Ulp1 as a sensor of NPC integrity and Hek2 as a repressor of NPC biogenesis. The nuclear pore complex is crucial for mediating nucleocytoplasmic exchanges. Here the authors use budding yeast to reveal a mechanism responsible of maintaining nucleoporin homeostasis by sensing changes in the complex integrity and further altering the metabolism of the corresponding mRNAs.
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Robijns J, Houthaeve G, Braeckmans K, De Vos WH. Loss of Nuclear Envelope Integrity in Aging and Disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 336:205-222. [DOI: 10.1016/bs.ircmb.2017.07.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Bonnet A, Grosso AR, Elkaoutari A, Coleno E, Presle A, Sridhara SC, Janbon G, Géli V, de Almeida SF, Palancade B. Introns Protect Eukaryotic Genomes from Transcription-Associated Genetic Instability. Mol Cell 2017; 67:608-621.e6. [PMID: 28757210 DOI: 10.1016/j.molcel.2017.07.002] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 05/19/2017] [Accepted: 06/30/2017] [Indexed: 12/31/2022]
Abstract
Transcription is a source of genetic instability that can notably result from the formation of genotoxic DNA:RNA hybrids, or R-loops, between the nascent mRNA and its template. Here we report an unexpected function for introns in counteracting R-loop accumulation in eukaryotic genomes. Deletion of endogenous introns increases R-loop formation, while insertion of an intron into an intronless gene suppresses R-loop accumulation and its deleterious impact on transcription and recombination in yeast. Recruitment of the spliceosome onto the mRNA, but not splicing per se, is shown to be critical to attenuate R-loop formation and transcription-associated genetic instability. Genome-wide analyses in a number of distant species differing in their intron content, including human, further revealed that intron-containing genes and the intron-richest genomes are best protected against R-loop accumulation and subsequent genetic instability. Our results thereby provide a possible rationale for the conservation of introns throughout the eukaryotic lineage.
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Affiliation(s)
- Amandine Bonnet
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France
| | - Ana R Grosso
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1600-276 Lisboa, Portugal
| | - Abdessamad Elkaoutari
- Cancer Research Center of Marseille (CRCM), Equipe Labellisée Ligue, U1068 INSERM, UMR7258 CNRS, Institut Paoli-Calmettes, Aix Marseille University, 13284 Marseille, France
| | - Emeline Coleno
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France
| | - Adrien Presle
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France
| | - Sreerama C Sridhara
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1600-276 Lisboa, Portugal
| | - Guilhem Janbon
- Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, 75015 Paris, France
| | - Vincent Géli
- Cancer Research Center of Marseille (CRCM), Equipe Labellisée Ligue, U1068 INSERM, UMR7258 CNRS, Institut Paoli-Calmettes, Aix Marseille University, 13284 Marseille, France
| | - Sérgio F de Almeida
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1600-276 Lisboa, Portugal
| | - Benoit Palancade
- Institut Jacques Monod, CNRS, UMR 7592, Université Paris Diderot, Sorbonne Paris Cité, 75013 Paris, France.
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21
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Li Y, Bor YC, Fitzgerald MP, Lee KS, Rekosh D, Hammarskjold ML. An NXF1 mRNA with a retained intron is expressed in hippocampal and neocortical neurons and is translated into a protein that functions as an Nxf1 cofactor. Mol Biol Cell 2016; 27:3903-3912. [PMID: 27708137 PMCID: PMC5170612 DOI: 10.1091/mbc.e16-07-0515] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 09/14/2016] [Accepted: 09/26/2016] [Indexed: 12/22/2022] Open
Abstract
A small Nxf1 protein, expressed from an NXF1 mRNA with a retained intron is highly expressed in rodent hippocampal and neocortical neurons, colocalizes with Staufen2 proteins in neuronal RNA granules, is present in polysomes, and replaces Nxt1 as an Nxf1 cofactor in export and expression of mRNA with retained introns. The Nxf1 protein is a major nuclear export receptor for the transport of mRNA, and it also is essential for export of retroviral mRNAs with retained introns. In the latter case, it binds to RNA elements known as constitutive transport elements (CTEs) and functions in conjunction with a cofactor known as Nxt1. The NXF1 gene also regulates expression of its own intron-containing RNA through the use of a functional CTE within intron 10. mRNA containing this intron is exported to the cytoplasm, where it can be translated into the 356–amino acid short Nxf1(sNxf1) protein, despite the fact that it is a prime candidate for nonsense-mediated decay (NMD). Here we demonstrate that sNxf1 is highly expressed in nuclei and dendrites of hippocampal and neocortical neurons in rodent brain. Additionally, we show that sNxf1 localizes in RNA granules in neurites of differentiated N2a mouse neuroblastoma cells, where it shows partial colocalization with Staufen2 isoform SS, a protein known to play a role in dendritic mRNA trafficking. We also show that sNxf1 forms heterodimers in conjunction with the full-length Nxf1 and that sNxf1 can replace Nxt1 to enhance the expression of CTE-containing mRNA and promote its association with polyribosomes.
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Affiliation(s)
- Ying Li
- Myles H. Thaler Center for AIDS and Human Retrovirus Research and Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Yeou-Cherng Bor
- Myles H. Thaler Center for AIDS and Human Retrovirus Research and Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Mark P Fitzgerald
- Departments of Neuroscience and Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Kevin S Lee
- Departments of Neuroscience and Neurosurgery, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - David Rekosh
- Myles H. Thaler Center for AIDS and Human Retrovirus Research and Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Marie-Louise Hammarskjold
- Myles H. Thaler Center for AIDS and Human Retrovirus Research and Department of Microbiology, Immunology, and Cancer Biology, University of Virginia School of Medicine, Charlottesville, VA 22908
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22
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Gonzalez-Hilarion S, Paulet D, Lee KT, Hon CC, Lechat P, Mogensen E, Moyrand F, Proux C, Barboux R, Bussotti G, Hwang J, Coppée JY, Bahn YS, Janbon G. Intron retention-dependent gene regulation in Cryptococcus neoformans. Sci Rep 2016; 6:32252. [PMID: 27577684 PMCID: PMC5006051 DOI: 10.1038/srep32252] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/03/2016] [Indexed: 01/28/2023] Open
Abstract
The biological impact of alternative splicing is poorly understood in fungi, although recent studies have shown that these microorganisms are usually intron-rich. In this study, we re-annotated the genome of C. neoformans var. neoformans using RNA-Seq data. Comparison with C. neoformans var. grubii revealed that more than 99% of ORF-introns are in the same exact position in the two varieties whereas UTR-introns are much less evolutionary conserved. We also confirmed that alternative splicing is very common in C. neoformans, affecting nearly all expressed genes. We also observed specific regulation of alternative splicing by environmental cues in this yeast. However, alternative splicing does not appear to be an efficient method to diversify the C. neoformans proteome. Instead, our data suggest the existence of an intron retention-dependent mechanism of gene expression regulation that is not dependent on NMD. This regulatory process represents an additional layer of gene expression regulation in fungi and provides a mechanism to tune gene expression levels in response to any environmental modification.
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Affiliation(s)
- Sara Gonzalez-Hilarion
- Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, F-75015, Paris, France
| | - Damien Paulet
- Institut Pasteur, Plate-forme transcriptome et Epigénome, Département Génomes et Génétique, F-75015, Paris, France
| | - Kyung-Tae Lee
- Department of Biotechnology, College of Life and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Chung-Chau Hon
- RIKEN Center for Life Science Technologies, Yokohama Institute, Division of Genomic Technology, Yokohama, 230-0045, Japan
| | - Pierre Lechat
- Institut Pasteur, HUB Bioinformatique et Biostatistique, C3BI, USR 3756 IP CNRS, F-75015, Paris, France
| | - Estelle Mogensen
- Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, F-75015, Paris, France
| | - Frédérique Moyrand
- Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, F-75015, Paris, France
| | - Caroline Proux
- Institut Pasteur, Plate-forme transcriptome et Epigénome, Département Génomes et Génétique, F-75015, Paris, France
| | - Rony Barboux
- Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, F-75015, Paris, France
| | - Giovanni Bussotti
- Institut Pasteur, HUB Bioinformatique et Biostatistique, C3BI, USR 3756 IP CNRS, F-75015, Paris, France
| | - Jungwook Hwang
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul, Korea
| | - Jean-Yves Coppée
- Institut Pasteur, Plate-forme transcriptome et Epigénome, Département Génomes et Génétique, F-75015, Paris, France
| | - Yong-Sun Bahn
- Department of Biotechnology, College of Life and Biotechnology, Yonsei University, Seoul 03722, Korea
| | - Guilhem Janbon
- Institut Pasteur, Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, F-75015, Paris, France
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23
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Ben-Yishay R, Ashkenazy AJ, Shav-Tal Y. Dynamic Encounters of Genes and Transcripts with the Nuclear Pore. Trends Genet 2016; 32:419-431. [DOI: 10.1016/j.tig.2016.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 04/20/2016] [Indexed: 01/04/2023]
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24
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Abstract
Nuclear pore complexes (NPCs) have been shown to regulate distinct steps of the gene expression process, from transcription to mRNA export. In particular, mRNAs expressed from intron-containing genes are surveyed by a specific NPC-dependent quality control pathway ensuring that unspliced mRNAs are retained within the nucleus. In this Extra View, we summarize the different approaches that have been developed to evaluate the contribution of various NPC components to the expression of intron-containing genes. We further present the mechanistic models that could account for pre-mRNA retention at the nuclear side of NPCs. Finally, we discuss the possibility that other stages of intron-containing gene expression could be regulated by nuclear pores, in particular through the regulation of mRNA biogenesis factors by the NPC-associated SUMO protease Ulp1.
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Affiliation(s)
- Amandine Bonnet
- a Institut Jacques Monod; CNRS; UMR 7592; Univ Paris Diderot ; Sorbonne Paris Cité; Paris , France
| | - Benoit Palancade
- a Institut Jacques Monod; CNRS; UMR 7592; Univ Paris Diderot ; Sorbonne Paris Cité; Paris , France
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