1
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Polák P, Garland W, Rathore O, Schmid M, Salerno-Kochan A, Jakobsen L, Gockert M, Gerlach P, Silla T, Andersen JS, Conti E, Jensen TH. Dual agonistic and antagonistic roles of ZC3H18 provide for co-activation of distinct nuclear RNA decay pathways. Cell Rep 2023; 42:113325. [PMID: 37889751 PMCID: PMC10720265 DOI: 10.1016/j.celrep.2023.113325] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 01/19/2023] [Accepted: 10/09/2023] [Indexed: 10/29/2023] Open
Abstract
The RNA exosome is a versatile ribonuclease. In the nucleoplasm of mammalian cells, it is assisted by its adaptors the nuclear exosome targeting (NEXT) complex and the poly(A) exosome targeting (PAXT) connection. Via its association with the ARS2 and ZC3H18 proteins, NEXT/exosome is recruited to capped and short unadenylated transcripts. Conversely, PAXT/exosome is considered to target longer and adenylated substrates via their poly(A) tails. Here, mutational analysis of the core PAXT component ZFC3H1 uncovers a separate branch of the PAXT pathway, which targets short adenylated RNAs and relies on a direct ARS2-ZFC3H1 interaction. We further demonstrate that similar acidic-rich short linear motifs of ZFC3H1 and ZC3H18 compete for a common ARS2 epitope. Consequently, while promoting NEXT function, ZC3H18 antagonizes PAXT activity. We suggest that this organization of RNA decay complexes provides co-activation of NEXT and PAXT at loci with abundant production of short exosome substrates.
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Affiliation(s)
- Patrik Polák
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark
| | - William Garland
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark
| | - Om Rathore
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark
| | - Manfred Schmid
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark
| | - Anna Salerno-Kochan
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried/Munich, Germany
| | - Lis Jakobsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M, Denmark
| | - Maria Gockert
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark
| | - Piotr Gerlach
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried/Munich, Germany
| | - Toomas Silla
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark
| | - Jens S Andersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M, Denmark
| | - Elena Conti
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried/Munich, Germany
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Universitetsbyen 81, Aarhus University, Aarhus, Denmark.
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2
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Wu G, Schmid M, Rib L, Polak P, Meola N, Sandelin A, Jensen TH. A Two-Layered Targeting Mechanism Underlies Nuclear RNA Sorting by the Human Exosome. Cell Rep 2021; 30:2387-2401.e5. [PMID: 32075771 DOI: 10.1016/j.celrep.2020.01.068] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/09/2019] [Accepted: 01/22/2020] [Indexed: 12/14/2022] Open
Abstract
Degradation of transcripts in human nuclei is primarily facilitated by the RNA exosome. To obtain substrate specificity, the exosome is aided by adaptors; in the nucleoplasm, those adaptors are the nuclear exosome-targeting (NEXT) complex and the poly(A) (pA) exosome-targeting (PAXT) connection. How these adaptors guide exosome targeting remains enigmatic. Employing high-resolution 3' end sequencing, we demonstrate that NEXT substrates arise from heterogenous and predominantly pA- 3' ends often covering kilobase-wide genomic regions. In contrast, PAXT targets harbor well-defined pA+ 3' ends defined by canonical pA site use. Irrespective of this clear division, NEXT and PAXT act redundantly in two ways: (1) regional redundancy, where the majority of exosome-targeted transcription units produce NEXT- and PAXT-sensitive RNA isoforms, and (2) isoform redundancy, where the PAXT connection ensures fail-safe decay of post-transcriptionally polyadenylated NEXT targets. In conjunction, this provides a two-layered targeting mechanism for efficient nuclear sorting of the human transcriptome.
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Affiliation(s)
- Guifen Wu
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, 8000 Aarhus C, Denmark
| | - Manfred Schmid
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, 8000 Aarhus C, Denmark
| | - Leonor Rib
- The Bioinformatics Centre, Department of Biology and Biotech Research and Innovation Centre, University of Copenhagen, Ole Maaloes Vej 5, 2200 Copenhagen, Denmark
| | - Patrik Polak
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, 8000 Aarhus C, Denmark
| | - Nicola Meola
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, 8000 Aarhus C, Denmark
| | - Albin Sandelin
- The Bioinformatics Centre, Department of Biology and Biotech Research and Innovation Centre, University of Copenhagen, Ole Maaloes Vej 5, 2200 Copenhagen, Denmark
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, 8000 Aarhus C, Denmark.
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3
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Silla T, Schmid M, Dou Y, Garland W, Milek M, Imami K, Johnsen D, Polak P, Andersen JS, Selbach M, Landthaler M, Jensen TH. The human ZC3H3 and RBM26/27 proteins are critical for PAXT-mediated nuclear RNA decay. Nucleic Acids Res 2020; 48:2518-2530. [PMID: 31950173 PMCID: PMC7049725 DOI: 10.1093/nar/gkz1238] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 12/18/2019] [Accepted: 12/30/2019] [Indexed: 12/21/2022] Open
Abstract
Recruitment of the human ribonucleolytic RNA exosome to nuclear polyadenylated (pA+) RNA is facilitated by the Poly(A) Tail eXosome Targeting (PAXT) connection. Besides its core dimer, formed by the exosome co-factor MTR4 and the ZFC3H1 protein, the PAXT connection remains poorly defined. By characterizing nuclear pA+-RNA bound proteomes as well as MTR4-ZFC3H1 containing complexes in conditions favoring PAXT assembly, we here uncover three additional proteins required for PAXT function: ZC3H3, RBM26 and RBM27 along with the known PAXT-associated protein, PABPN1. The zinc-finger protein ZC3H3 interacts directly with MTR4-ZFC3H1 and loss of any of the newly identified PAXT components results in the accumulation of PAXT substrates. Collectively, our results establish new factors involved in the turnover of nuclear pA+ RNA and suggest that these are limiting for PAXT activity.
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Affiliation(s)
- Toomas Silla
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - Manfred Schmid
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - Yuhui Dou
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - William Garland
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - Miha Milek
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13092 Berlin, Germany.,IRI Life Sciences, Institute für Biologie, Humboldt Universität zu Berlin, Philippstraße 13, 10115 Berlin, Germany
| | - Koshi Imami
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13092 Berlin, Germany.,Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Dennis Johnsen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - Patrik Polak
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - Jens S Andersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Matthias Selbach
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13092 Berlin, Germany.,Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Markus Landthaler
- Max Delbrück Center for Molecular Medicine, Robert-Rössle-Str. 10, 13092 Berlin, Germany.,IRI Life Sciences, Institute für Biologie, Humboldt Universität zu Berlin, Philippstraße 13, 10115 Berlin, Germany
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, 8000 Aarhus C, Denmark
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4
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Schmid M, Jensen TH. The Nuclear RNA Exosome and Its Cofactors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1203:113-132. [PMID: 31811632 DOI: 10.1007/978-3-030-31434-7_4] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
The RNA exosome is a highly conserved ribonuclease endowed with 3'-5' exonuclease and endonuclease activities. The multisubunit complex resides in both the nucleus and the cytoplasm, with varying compositions and activities between the two compartments. While the cytoplasmic exosome functions mostly in mRNA quality control pathways, the nuclear RNA exosome partakes in the 3'-end processing and complete decay of a wide variety of substrates, including virtually all types of noncoding (nc) RNAs. To handle these diverse tasks, the nuclear exosome engages with dedicated cofactors, some of which serve as activators by stimulating decay through oligoA addition and/or RNA helicase activities or, as adaptors, by recruiting RNA substrates through their RNA-binding capacities. Most nuclear exosome cofactors contain the essential RNA helicase Mtr4 (MTR4 in humans). However, apart from Mtr4, nuclear exosome cofactors have undergone significant evolutionary divergence. Here, we summarize biochemical and functional knowledge about the nuclear exosome and exemplify its cofactor variety by discussing the best understood model organisms-the budding yeast Saccharomyces cerevisiae, the fission yeast Schizosaccharomyces pombe, and human cells.
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Affiliation(s)
- Manfred Schmid
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark.
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5
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Lloret-Llinares M, Karadoulama E, Chen Y, Wojenski LA, Villafano GJ, Bornholdt J, Andersson R, Core L, Sandelin A, Jensen TH. The RNA exosome contributes to gene expression regulation during stem cell differentiation. Nucleic Acids Res 2018; 46:11502-11513. [PMID: 30212902 PMCID: PMC6265456 DOI: 10.1093/nar/gky817] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/29/2018] [Accepted: 09/09/2018] [Indexed: 12/27/2022] Open
Abstract
Gene expression programs change during cellular transitions. It is well established that a network of transcription factors and chromatin modifiers regulate RNA levels during embryonic stem cell (ESC) differentiation, but the full impact of post-transcriptional processes remains elusive. While cytoplasmic RNA turnover mechanisms have been implicated in differentiation, the contribution of nuclear RNA decay has not been investigated. Here, we differentiate mouse ESCs, depleted for the ribonucleolytic RNA exosome, into embryoid bodies to determine to which degree RNA abundance in the two states can be attributed to changes in transcription versus RNA decay by the exosome. As a general observation, we find that exosome depletion mainly leads to the stabilization of RNAs from lowly transcribed loci, including several protein-coding genes. Depletion of the nuclear exosome cofactor RBM7 leads to similar effects. In particular, transcripts that are differentially expressed between states tend to be more exosome sensitive in the state where expression is low. We conclude that the RNA exosome contributes to down-regulation of transcripts with disparate expression, often in conjunction with transcriptional down-regulation.
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Affiliation(s)
| | - Evdoxia Karadoulama
- Department of Molecular Biology and Genetics, Aarhus University, Denmark
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Denmark
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Denmark
| | - Yun Chen
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Denmark
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Denmark
| | - Luke A Wojenski
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
| | - Geno J Villafano
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
| | - Jette Bornholdt
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Denmark
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Denmark
| | - Robin Andersson
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Denmark
| | - Leighton Core
- Department of Molecular and Cell Biology, Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
| | - Albin Sandelin
- The Bioinformatics Centre, Department of Biology, University of Copenhagen, Denmark
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Denmark
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6
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Tudek A, Lloret-Llinares M, Jensen TH. The multitasking polyA tail: nuclear RNA maturation, degradation and export. Philos Trans R Soc Lond B Biol Sci 2018; 373:rstb.2018.0169. [PMID: 30397105 DOI: 10.1098/rstb.2018.0169] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2018] [Indexed: 12/17/2022] Open
Abstract
A polyA (pA) tail is an essential modification added to the 3' ends of a wide range of RNAs at different stages of their metabolism. Here, we describe the main sources of polyadenylation and outline their underlying biochemical interactions within the nuclei of budding yeast Saccharomyces cerevisiae, human cells and, when relevant, the fission yeast Schizosaccharomyces pombe Polyadenylation mediated by the S. cerevisiae Trf4/5 enzymes, and their human homologues PAPD5/7, typically leads to the 3'-end trimming or complete decay of non-coding RNAs. By contrast, the primary function of canonical pA polymerases (PAPs) is to produce stable and nuclear export-competent mRNAs. However, this dichotomy is becoming increasingly blurred, at least in S. pombe and human cells, where polyadenylation mediated by canonical PAPs may also result in transcript decay.This article is part of the theme issue '5' and 3' modifications controlling RNA degradation'.
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Affiliation(s)
- Agnieszka Tudek
- Department of Molecular Biology and Genetics, Aarhus University, C. F. Møllers Allé 3, building 1130, 8000 Aarhus C, Denmark
| | - Marta Lloret-Llinares
- Department of Molecular Biology and Genetics, Aarhus University, C. F. Møllers Allé 3, building 1130, 8000 Aarhus C, Denmark
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, C. F. Møllers Allé 3, building 1130, 8000 Aarhus C, Denmark
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7
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8
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Meola N, Jensen TH. Targeting the nuclear RNA exosome: Poly(A) binding proteins enter the stage. RNA Biol 2017; 14:820-826. [PMID: 28421898 DOI: 10.1080/15476286.2017.1312227] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Centrally positioned in nuclear RNA metabolism, the exosome deals with virtually all transcript types. This 3'-5' exo- and endo-nucleolytic degradation machine is guided to its RNA targets by adaptor proteins that enable substrate recognition. Recently, the discovery of the 'Poly(A) tail exosome targeting (PAXT)' connection as an exosome adaptor to human nuclear polyadenylated transcripts has relighted the interest of poly(A) binding proteins (PABPs) in both RNA productive and destructive processes.
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Affiliation(s)
- Nicola Meola
- a Department of Molecular Biology and Genetics , Aarhus University , Aarhus C , Denmark
| | - Torben Heick Jensen
- a Department of Molecular Biology and Genetics , Aarhus University , Aarhus C , Denmark
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9
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Meola N, Domanski M, Karadoulama E, Chen Y, Gentil C, Pultz D, Vitting-Seerup K, Lykke-Andersen S, Andersen JS, Sandelin A, Jensen TH. Identification of a Nuclear Exosome Decay Pathway for Processed Transcripts. Mol Cell 2016; 64:520-533. [PMID: 27871484 DOI: 10.1016/j.molcel.2016.09.025] [Citation(s) in RCA: 173] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 08/18/2016] [Accepted: 09/20/2016] [Indexed: 12/20/2022]
Abstract
The RNA exosome is fundamental for the degradation of RNA in eukaryotic nuclei. Substrate targeting is facilitated by its co-factor Mtr4p/hMTR4, which links to RNA-binding protein adaptors. One example is the trimeric human nuclear exosome targeting (NEXT) complex, which is composed of hMTR4, the Zn-finger protein ZCCHC8, and the RNA-binding factor RBM7. NEXT primarily targets early and unprocessed transcripts, which demands a rationale for how the nuclear exosome recognizes processed RNAs. Here, we describe the poly(A) tail exosome targeting (PAXT) connection, which comprises the ZFC3H1 Zn-knuckle protein as a central link between hMTR4 and the nuclear poly(A)-binding protein PABPN1. Individual depletion of ZFC3H1 and PABPN1 results in the accumulation of common transcripts that are generally both longer and more extensively polyadenylated than NEXT substrates. Importantly, ZFC3H1/PABPN1 and ZCCHC8/RBM7 contact hMTR4 in a mutually exclusive manner, revealing that the exosome targets nuclear transcripts of different maturation status by substituting its hMTR4-associating adaptors.
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Affiliation(s)
- Nicola Meola
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, DK-8000 Aarhus C, Denmark
| | - Michal Domanski
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, DK-8000 Aarhus C, Denmark
| | - Evdoxia Karadoulama
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, DK-8000 Aarhus C, Denmark; The Bioinformatics Centre, Department of Biology & Biotech Research and Innovation Centre, University of Copenhagen, Ole Maaloesvej 5, DK-2200 Copenhagen, Denmark
| | - Yun Chen
- The Bioinformatics Centre, Department of Biology & Biotech Research and Innovation Centre, University of Copenhagen, Ole Maaloesvej 5, DK-2200 Copenhagen, Denmark
| | - Coline Gentil
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, DK-8000 Aarhus C, Denmark
| | - Dennis Pultz
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark
| | - Kristoffer Vitting-Seerup
- The Bioinformatics Centre, Department of Biology & Biotech Research and Innovation Centre, University of Copenhagen, Ole Maaloesvej 5, DK-2200 Copenhagen, Denmark
| | - Søren Lykke-Andersen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, DK-8000 Aarhus C, Denmark
| | - Jens S Andersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense, Denmark
| | - Albin Sandelin
- The Bioinformatics Centre, Department of Biology & Biotech Research and Innovation Centre, University of Copenhagen, Ole Maaloesvej 5, DK-2200 Copenhagen, Denmark
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Allé 3, Building 1130, DK-8000 Aarhus C, Denmark.
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10
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Goebels C, Thonn A, Gonzalez-Hilarion S, Rolland O, Moyrand F, Beilharz TH, Janbon G. Introns regulate gene expression in Cryptococcus neoformans in a Pab2p dependent pathway. PLoS Genet 2013; 9:e1003686. [PMID: 23966870 PMCID: PMC3744415 DOI: 10.1371/journal.pgen.1003686] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 06/17/2013] [Indexed: 11/18/2022] Open
Abstract
Most Cryptococccus neoformans genes are interrupted by introns, and alternative splicing occurs very often. In this study, we examined the influence of introns on C. neoformans gene expression. For most tested genes, elimination of introns greatly reduces mRNA accumulation. Strikingly, the number and the position of introns modulate the gene expression level in a cumulative manner. A screen for mutant strains able to express functionally an intronless allele revealed that the nuclear poly(A) binding protein Pab2 modulates intron-dependent regulation of gene expression in C. neoformans. PAB2 deletion partially restored accumulation of intronless mRNA. In addition, our results demonstrated that the essential nucleases Rrp44p and Xrn2p are implicated in the degradation of mRNA transcribed from an intronless allele in C. neoformans. Double mutant constructions and over-expression experiments suggested that Pab2p and Xrn2p could act in the same pathway whereas Rrp44p appears to act independently. Finally, deletion of the RRP6 or the CID14 gene, encoding the nuclear exosome nuclease and the TRAMP complex associated poly(A) polymerase, respectively, has no effect on intronless allele expression. Cryptococcus neoformans is a major human pathogen responsible for deadly infection in immunocompromised patients. The analysis of its genome previously revealed that most of its genes are interrupted by introns. Here, we demonstrate that introns modulate gene expression in a cumulative manner. We also demonstrate that introns can play a positive or a negative role in this process. We identify a nuclear poly(A) binding protein (Pab2p) as implicated in the intron-dependent control of gene expression in C. neoformans. We also demonstrate that the essential nucleases Rrp44p and Xrn2p are implicated in two independent pathways controlling the intron-dependent regulation of gene expression in C. neoformans. Xrn2p regulation seems to depend on Pab2p whereas Rrp44p acts independently. In contrast, the other exosome nuclease Rrp6p and the TRAMP associated poly(A) polymerase Cid14p do not appear to be implicated in this regulation. Our results provide new insights into the regulation of gene expression in eukaryotes and more specifically into the biology and virulence of C. neoformans.
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Affiliation(s)
- Carolin Goebels
- Institut Pasteur, Unité des Aspergillus, Département Parasitologie et Mycologie, Paris, France
| | - Aline Thonn
- Institut Pasteur, Unité des Aspergillus, Département Parasitologie et Mycologie, Paris, France
| | - Sara Gonzalez-Hilarion
- Institut Pasteur, Unité des Aspergillus, Département Parasitologie et Mycologie, Paris, France
| | - Olga Rolland
- Institut Pasteur, Unité des Aspergillus, Département Parasitologie et Mycologie, Paris, France
| | - Frederique Moyrand
- Institut Pasteur, Unité des Aspergillus, Département Parasitologie et Mycologie, Paris, France
| | - Traude H. Beilharz
- Monash University, Department of Biochemistry and Molecular Biology, Clayton, Australia
| | - Guilhem Janbon
- Institut Pasteur, Unité des Aspergillus, Département Parasitologie et Mycologie, Paris, France
- * E-mail:
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11
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Schmid M, Poulsen MB, Olszewski P, Pelechano V, Saguez C, Gupta I, Steinmetz LM, Moore C, Jensen TH. Rrp6p controls mRNA poly(A) tail length and its decoration with poly(A) binding proteins. Mol Cell 2012; 47:267-80. [PMID: 22683267 DOI: 10.1016/j.molcel.2012.05.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Revised: 03/30/2012] [Accepted: 05/01/2012] [Indexed: 11/17/2022]
Abstract
Poly(A) (pA) tail binding proteins (PABPs) control mRNA polyadenylation, stability, and translation. In a purified system, S. cerevisiae PABPs, Pab1p and Nab2p, are individually sufficient to provide normal pA tail length. However, it is unknown how this occurs in more complex environments. Here we find that the nuclear exosome subunit Rrp6p counteracts the in vitro and in vivo extension of mature pA tails by the noncanonical pA polymerase Trf4p. Moreover, PABP loading onto nascent pA tails is controlled by Rrp6p; while Pab1p is the major PABP, Nab2p only associates in the absence of Rrp6p. This is because Rrp6p can interact with Nab2p and displace it from pA tails, potentially leading to RNA turnover, as evidenced for certain pre-mRNAs. We suggest that a nuclear mRNP surveillance step involves targeting of Rrp6p by Nab2p-bound pA-tailed RNPs and that pre-mRNA abundance is regulated at this level.
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Affiliation(s)
- Manfred Schmid
- Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology and Genetics, Aarhus University, C.F. Møllers Alle 3, Building 1130, DK-8000 Aarhus C., Denmark
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12
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Mühlemann O, Jensen TH. mRNP quality control goes regulatory. Trends Genet 2012; 28:70-7. [DOI: 10.1016/j.tig.2011.11.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 11/04/2011] [Accepted: 11/08/2011] [Indexed: 01/19/2023]
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13
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Vazquez-Pianzola P, Urlaub H, Suter B. Pabp binds to the osk 3'UTR and specifically contributes to osk mRNA stability and oocyte accumulation. Dev Biol 2011; 357:404-18. [PMID: 21782810 DOI: 10.1016/j.ydbio.2011.07.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 07/05/2011] [Accepted: 07/07/2011] [Indexed: 12/16/2022]
Abstract
RNA localization is tightly coordinated with RNA stability and translation control. Bicaudal-D (Bic-D), Egalitarian (Egl), microtubules and their motors are part of a Drosophila transport machinery that localizes mRNAs to specific cellular regions during oogenesis and embryogenesis. We identified the Poly(A)-binding protein (Pabp) as a protein that forms an RNA-dependent complex with Bic-D in embryos and ovaries. pabp also interacts genetically with Bic-D and, similar to Bic-D, pabp is essential in the germline for oocyte growth and accumulation of osk mRNA in the oocyte. In the absence of pabp, reduced stability of osk mRNA and possibly also defects in osk mRNA transport prevent normal oocyte localization of osk mRNA. pabp also interacts genetically with osk and lack of one copy of pabp(+) causes osk to become haploinsufficient. Moreover, pointing to a poly(A)-independent role, Pabp binds to A-rich sequences (ARS) in the osk 3'UTR and these turned out to be required in vivo for osk function during early oogenesis. This effect of pabp on osk mRNA is specific for this RNA and other tested mRNAs localizing to the oocyte are less and more indirectly affected by the lack of pabp.
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Importance of polyadenylation in the selective elimination of meiotic mRNAs in growing S. pombe cells. EMBO J 2010; 29:2173-81. [PMID: 20512112 PMCID: PMC2905246 DOI: 10.1038/emboj.2010.108] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Accepted: 04/30/2010] [Indexed: 11/09/2022] Open
Abstract
A number of meiosis-specific mRNAs are initially weakly transcribed, but then selectively removed during fission yeast mitotic growth. These mRNAs harbour a region termed DSR (determinant of selective removal), which is recognized by the YTH family RNA-binding protein Mmi1p. Mmi1p directs the destruction of these mRNAs in collaboration with nuclear exosomes. However, detailed molecular mechanisms underlying this process of selective mRNA elimination have remained elusive. In this study, we demonstrate the critical role of polyadenylation in this process. Two-hybrid and genetic screens revealed potential interactions between Mmi1p and proteins involved in polyadenylation. Additional investigations showed that destruction of DSR-containing mRNAs by exosomes required polyadenylation by a canonical poly(A) polymerase. The recruitment of Pab2p, a poly(A)-binding protein, to the poly(A) tail was also necessary for mRNA destruction. In cells undergoing vegetative growth, Mmi1p localized with exosomes, Pab2p, and components of the polyadenylation complex in several patchy structures in the nucleoplasm. These patches may represent the sites for degradation of meiosis-specific mRNAs with untimely expression.
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