1
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Palazzo AF, Qiu Y, Kang YM. mRNA nuclear export: how mRNA identity features distinguish functional RNAs from junk transcripts. RNA Biol 2024; 21:1-12. [PMID: 38091265 PMCID: PMC10732640 DOI: 10.1080/15476286.2023.2293339] [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] [Accepted: 12/05/2023] [Indexed: 12/18/2023] Open
Abstract
The division of the cellular space into nucleoplasm and cytoplasm promotes quality control mechanisms that prevent misprocessed mRNAs and junk RNAs from gaining access to the translational machinery. Here, we explore how properly processed mRNAs are distinguished from both misprocessed mRNAs and junk RNAs by the presence or absence of various 'identity features'.
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Affiliation(s)
| | - Yi Qiu
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Yoon Mo Kang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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2
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Khan M, Hou S, Chen M, Lei H. Mechanisms of RNA export and nuclear retention. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1755. [PMID: 35978483 DOI: 10.1002/wrna.1755] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 06/21/2022] [Accepted: 07/06/2022] [Indexed: 05/13/2023]
Abstract
With the identification of huge amount of noncoding RNAs in recent years, the concept of RNA localization has extended from traditional mRNA export to RNA export of mRNA and ncRNA as well as nuclear retention of ncRNA. This review aims to summarize the recent findings from studies on the mechanisms of export of different RNAs and nuclear retention of some lncRNAs in higher eukaryotes, with a focus on splicing-dependent TREX recruitment for the export of spliced mRNA and the sequence-dependent mechanism of mRNA export in the absence of splicing. In addition, evidence to support the involvement of m6 A modification in RNA export with the coordination between the methylase complex and TREX complex as well as sequence-dependent nuclear retention of lncRNA is recapitulated. Finally, a model of sequence-dependent RNA localization is proposed along with the many questions that remain to be answered. This article is categorized under: RNA Export and Localization > RNA Localization RNA Export and Localization > Nuclear Export/Import.
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Affiliation(s)
- Misbah Khan
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
| | - Shuai Hou
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
| | - Mo Chen
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
| | - Haixin Lei
- Institute of Cancer Stem Cell, Dalian Medical University, Dalian, China
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3
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Esparza M, Bhat P, Fontoura BMA. Viral-host interactions during splicing and nuclear export of influenza virus mRNAs. Curr Opin Virol 2022; 55:101254. [PMID: 35908311 PMCID: PMC9945342 DOI: 10.1016/j.coviro.2022.101254] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/23/2022] [Accepted: 06/30/2022] [Indexed: 02/07/2023]
Abstract
As influenza-A viruses (IAV) replicate in the host cell nucleus, intranuclear pathways are usurped for viral gene expression. The eight genomic viral ribonucleoproteins (vRNPs) segments of IAV are transcribed and two generate viral mRNAs (M and NS) that undergo alternative splicing followed by export from the nucleus. The focus of this review is on viral RNA splicing and nuclear export. Recent mechanistic advances on M and NS splicing show differential regulation by RNA-binding proteins as well as distinct intranuclear localization. After a review of IAV splicing, we will discuss the nuclear export of viral mRNAs, which occur by interacting with specific constituents of the host mRNA export machinery that translocate viral mRNAs through the nuclear pore complex for translation in the cytoplasm.
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4
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Lee ES, Smith HW, Wolf EJ, Guvenek A, Wang YE, Emili A, Tian B, Palazzo AF. ZFC3H1 and U1-70K promote the nuclear retention of mRNAs with 5' splice site motifs within nuclear speckles. RNA (NEW YORK, N.Y.) 2022; 28:878-894. [PMID: 35351812 PMCID: PMC9074902 DOI: 10.1261/rna.079104.122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 03/12/2022] [Indexed: 05/22/2023]
Abstract
Quality control of mRNA represents an important regulatory mechanism for gene expression in eukaryotes. One component of this quality control is the nuclear retention and decay of misprocessed RNAs. Previously, we demonstrated that mature mRNAs containing a 5' splice site (5'SS) motif, which is typically found in misprocessed RNAs such as intronic polyadenylated (IPA) transcripts, are nuclear retained and degraded. Using high-throughput sequencing of cellular fractions, we now demonstrate that IPA transcripts require the zinc finger protein ZFC3H1 for their nuclear retention and degradation. Using reporter mRNAs, we demonstrate that ZFC3H1 promotes the nuclear retention of mRNAs with intact 5'SS motifs by sequestering them into nuclear speckles. Furthermore, we find that U1-70K, a component of the spliceosomal U1 snRNP, is also required for the nuclear retention of these reporter mRNAs and likely functions in the same pathway as ZFC3H1. Finally, we show that the disassembly of nuclear speckles impairs the nuclear retention of reporter mRNAs with 5'SS motifs. Our results highlight a splicing independent role of U1 snRNP and indicate that it works in conjunction with ZFC3H1 in preventing the nuclear export of misprocessed mRNAs by sequestering them into nuclear speckles.
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Affiliation(s)
- Eliza S Lee
- Department of Biochemistry, University of Toronto, Ontario M5S 1A8, Canada
| | - Harrison W Smith
- Department of Biochemistry, University of Toronto, Ontario M5S 1A8, Canada
| | - Eric J Wolf
- Department of Molecular Genetics, University of Toronto, Ontario M5S 1A8, Canada
| | - Aysegul Guvenek
- Rutgers New Jersey Medical School, Newark, New Jersey 07103, USA
| | - Yifan E Wang
- Department of Biochemistry, University of Toronto, Ontario M5S 1A8, Canada
| | - Andrew Emili
- Department of Molecular Genetics, University of Toronto, Ontario M5S 1A8, Canada
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts 02118, USA
| | - Bin Tian
- Rutgers New Jersey Medical School, Newark, New Jersey 07103, USA
- Wistar Institute, Philadelphia, Pennsylvania 19104, USA
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5
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Panichnantakul P, Patel A, Tse EYW, Wyatt HDM. An open-source platform to quantify subnuclear foci and protein colocalization in response to replication stress. DNA Repair (Amst) 2021; 105:103156. [PMID: 34139663 DOI: 10.1016/j.dnarep.2021.103156] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 06/04/2021] [Accepted: 06/05/2021] [Indexed: 11/28/2022]
Abstract
Nuclear reorganization, including the localization of proteins into discrete subnuclear foci, is a hallmark of the cellular response to DNA damage and replication stress. These foci are thought to represent transient environments or repair factories, in which the lesion is sequestered with molecules and co-factors that catalyze repair. For example, nuclear foci contain signaling proteins that recruit transducer proteins. One important class of transducers is the structure-selective endonucleases, such as SLX1-SLX4, MUS81-EME1, and XPF-ERCC1, which remove branched DNA structures that form during repair. The relocalization of structure-selective endonucleases into subnuclear foci provides a visual read-out for the presence of direct DNA damage, replication barriers, or DNA entanglements and can be monitored using fluorescence microscopy. By simultaneously probing for two or more fluorescent signals, fluorescence microscopy can also provide insights into the proximal association of proteins within a local environment. Here, we report an open-source and semi-automated method to detect and quantify subnuclear foci, as well as foci colocalization and the accompanying pixel-based colocalization metrics. We use this pipeline to show that pre-mitotic nuclei contain a basal threshold of foci marked by SLX1-SLX4, MUS81, or XPF. Some of these foci colocalize with FANCD2 and have a high degree of correlation and co-occurrence. We also show that pre-mitotic cells experiencing replication stress contain elevated levels of foci containing SLX1-SLX4 or XPF, but not MUS81. These results point towards a role for SLX1-SLX4 and XPF-ERCC1 in the early cellular response to replication stress. Nevertheless, most of the foci that form in response to replication stress contain either FANCD2 or one of the three endonucleases. Altogether, our work highlights the compositional heterogeneity of subnuclear foci that form in response to replication stress. We also describe a user-friendly pipeline that can be used to characterize these dynamic structures.
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Affiliation(s)
- Pudchalaluck Panichnantakul
- Department of Biochemistry, University of Toronto, MaRS Centre, 661 University Ave., Toronto, ON, M5G 1M1, Canada
| | - Ayushi Patel
- Department of Biochemistry, University of Toronto, MaRS Centre, 661 University Ave., Toronto, ON, M5G 1M1, Canada
| | - Elizabeth Y W Tse
- Department of Biochemistry, University of Toronto, MaRS Centre, 661 University Ave., Toronto, ON, M5G 1M1, Canada
| | - Haley D M Wyatt
- Department of Biochemistry, University of Toronto, MaRS Centre, 661 University Ave., Toronto, ON, M5G 1M1, Canada; Canada Research Chairs Program, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, ON, M5S 1A8, Canada.
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6
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Lee ES, Wolf EJ, Ihn SSJ, Smith HW, Emili A, Palazzo AF. TPR is required for the efficient nuclear export of mRNAs and lncRNAs from short and intron-poor genes. Nucleic Acids Res 2021; 48:11645-11663. [PMID: 33091126 PMCID: PMC7672458 DOI: 10.1093/nar/gkaa919] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/21/2020] [Accepted: 10/02/2020] [Indexed: 12/14/2022] Open
Abstract
While splicing has been shown to enhance nuclear export, it has remained unclear whether mRNAs generated from intronless genes use specific machinery to promote their export. Here, we investigate the role of the major nuclear pore basket protein, TPR, in regulating mRNA and lncRNA nuclear export in human cells. By sequencing mRNA from the nucleus and cytosol of control and TPR-depleted cells, we provide evidence that TPR is required for the efficient nuclear export of mRNAs and lncRNAs that are generated from short transcripts that tend to have few introns, and we validate this with reporter constructs. Moreover, in TPR-depleted cells reporter mRNAs generated from short transcripts accumulate in nuclear speckles and are bound to Nxf1. These observations suggest that TPR acts downstream of Nxf1 recruitment and may allow mRNAs to leave nuclear speckles and properly dock with the nuclear pore. In summary, our study provides one of the first examples of a factor that is specifically required for the nuclear export of intronless and intron-poor mRNAs and lncRNAs.
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Affiliation(s)
- Eliza S Lee
- University of Toronto, Department of Biochemistry, Canada
| | - Eric J Wolf
- University of Toronto, Department of Molecular Genetics, Canada
| | - Sean S J Ihn
- University of Toronto, Department of Biochemistry, Canada
| | | | - Andrew Emili
- University of Toronto, Department of Molecular Genetics, Canada.,Boston University School of Medicine, Department of Biochemistry, Boston, MA, USA
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7
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Shen Q, Wang YE, Truong M, Mahadevan K, Wu JJ, Zhang H, Li J, Smith HW, Smibert CA, Palazzo AF. RanBP2/Nup358 enhances miRNA activity by sumoylating Argonautes. PLoS Genet 2021; 17:e1009378. [PMID: 33600493 PMCID: PMC7924746 DOI: 10.1371/journal.pgen.1009378] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 03/02/2021] [Accepted: 01/25/2021] [Indexed: 02/07/2023] Open
Abstract
Mutations in RanBP2 (also known as Nup358), one of the main components of the cytoplasmic filaments of the nuclear pore complex, contribute to the overproduction of acute necrotizing encephalopathy (ANE1)-associated cytokines. Here we report that RanBP2 represses the translation of the interleukin 6 (IL6) mRNA, which encodes a cytokine that is aberrantly up-regulated in ANE1. Our data indicates that soon after its production, the IL6 messenger ribonucleoprotein (mRNP) recruits Argonautes bound to let-7 microRNA. After this mRNP is exported to the cytosol, RanBP2 sumoylates mRNP-associated Argonautes, thereby stabilizing them and enforcing mRNA silencing. Collectively, these results support a model whereby RanBP2 promotes an mRNP remodelling event that is critical for the miRNA-mediated suppression of clinically relevant mRNAs, such as IL6.
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Affiliation(s)
- Qingtang Shen
- School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, China
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Yifan E. Wang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Mathew Truong
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Kohila Mahadevan
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Jingze J. Wu
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Hui Zhang
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Jiawei Li
- School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, China
| | - Harrison W. Smith
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Craig A. Smibert
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
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8
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Out or decay: fate determination of nuclear RNAs. Essays Biochem 2020; 64:895-905. [DOI: 10.1042/ebc20200005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 08/12/2020] [Accepted: 08/24/2020] [Indexed: 02/08/2023]
Abstract
Abstract
In eukaryotes, RNAs newly synthesized by RNA polymerase II (RNAPII) undergo several processing steps prior to transport to the cytoplasm. It has long been known that RNAs with defects in processing or export are removed in the nucleus. Recent studies revealed that RNAs without apparent defects are also subjected to nuclear degradation, indicating that nuclear RNA fate is determined in a more complex and dynamic way than previously thought. Nuclear RNA sorting directly determines the quality and quantity of RNA pools for future translation and thus is of significant importance. In this essay, we will summarize recent studies on this topic, mainly focusing on findings in mammalian system, and discuss about important remaining questions and possible biological relevance for nuclear RNA fate determination.
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9
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Palazzo AF, Kang YM. GC-content biases in protein-coding genes act as an "mRNA identity" feature for nuclear export. Bioessays 2020; 43:e2000197. [PMID: 33165929 DOI: 10.1002/bies.202000197] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/30/2020] [Accepted: 10/01/2020] [Indexed: 01/11/2023]
Abstract
It has long been observed that human protein-coding genes have a particular distribution of GC-content: the 5' end of these genes has high GC-content while the 3' end has low GC-content. In 2012, it was proposed that this pattern of GC-content could act as an mRNA identity feature that would lead to it being better recognized by the cellular machinery to promote its nuclear export. In contrast, junk RNA, which largely lacks this feature, would be retained in the nucleus and targeted for decay. Now two recent papers have provided evidence that GC-content does promote the nuclear export of many mRNAs in human cells.
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Affiliation(s)
- Alexander F Palazzo
- Department of Biochemistry, University of Toronto, Toronto, ON, M5G 1M1, Canada
| | - Yoon Mo Kang
- Department of Biochemistry, University of Toronto, Toronto, ON, M5G 1M1, Canada
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10
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Gales JP, Kubina J, Geldreich A, Dimitrova M. Strength in Diversity: Nuclear Export of Viral RNAs. Viruses 2020; 12:E1014. [PMID: 32932882 PMCID: PMC7551171 DOI: 10.3390/v12091014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 12/11/2022] Open
Abstract
The nuclear export of cellular mRNAs is a complex process that requires the orchestrated participation of many proteins that are recruited during the early steps of mRNA synthesis and processing. This strategy allows the cell to guarantee the conformity of the messengers accessing the cytoplasm and the translation machinery. Most transcripts are exported by the exportin dimer Nuclear RNA export factor 1 (NXF1)-NTF2-related export protein 1 (NXT1) and the transcription-export complex 1 (TREX1). Some mRNAs that do not possess all the common messenger characteristics use either variants of the NXF1-NXT1 pathway or CRM1, a different exportin. Viruses whose mRNAs are synthesized in the nucleus (retroviruses, the vast majority of DNA viruses, and influenza viruses) exploit both these cellular export pathways. Viral mRNAs hijack the cellular export machinery via complex secondary structures recognized by cellular export factors and/or viral adapter proteins. This way, the viral transcripts succeed in escaping the host surveillance system and are efficiently exported for translation, allowing the infectious cycle to proceed. This review gives an overview of the cellular mRNA nuclear export mechanisms and presents detailed insights into the most important strategies that viruses use to export the different forms of their RNAs from the nucleus to the cytoplasm.
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Affiliation(s)
- Jón Pol Gales
- Institut de Biologie Moléculaire des Plantes, The French National Center for Scientific Research (CNRS) UPR2357, Université de Strasbourg, F-67084 Strasbourg, France; (J.P.G.); (J.K.); (A.G.)
| | - Julie Kubina
- Institut de Biologie Moléculaire des Plantes, The French National Center for Scientific Research (CNRS) UPR2357, Université de Strasbourg, F-67084 Strasbourg, France; (J.P.G.); (J.K.); (A.G.)
- SVQV UMR-A 1131, INRAE, Université de Strasbourg, F-68000 Colmar, France
| | - Angèle Geldreich
- Institut de Biologie Moléculaire des Plantes, The French National Center for Scientific Research (CNRS) UPR2357, Université de Strasbourg, F-67084 Strasbourg, France; (J.P.G.); (J.K.); (A.G.)
| | - Maria Dimitrova
- Institut de Biologie Moléculaire des Plantes, The French National Center for Scientific Research (CNRS) UPR2357, Université de Strasbourg, F-67084 Strasbourg, France; (J.P.G.); (J.K.); (A.G.)
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11
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Hasenson SE, Shav‐Tal Y. Speculating on the Roles of Nuclear Speckles: How RNA‐Protein Nuclear Assemblies Affect Gene Expression. Bioessays 2020; 42:e2000104. [DOI: 10.1002/bies.202000104] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/17/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Sarah E. Hasenson
- The Mina & Everard Goodman Faculty of Life Sciences and the Institute of Nanotechnology and Advanced Materials Bar‐Ilan University Ramat Gan 4481400 Israel
| | - Yaron Shav‐Tal
- The Mina & Everard Goodman Faculty of Life Sciences and the Institute of Nanotechnology and Advanced Materials Bar‐Ilan University Ramat Gan 4481400 Israel
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12
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Bruter AV, Kalashnikova MV, Prytyko AP, Belyavsky AV. Maintenance of Plasmid Expression in vivo Depends Primarily on the CpG Contents of the Vector and Transgene. Mol Biol 2020. [DOI: 10.1134/s0026893320030048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Esparza M, Mor A, Niederstrasser H, White K, White A, Zhang K, Gao S, Wang J, Liang J, Sho S, Sakthivel R, Sathe AA, Xing C, Muñoz-Moreno R, Shay JW, García-Sastre A, Ready J, Posner B, Fontoura BMA. Chemical intervention of influenza virus mRNA nuclear export. PLoS Pathog 2020; 16:e1008407. [PMID: 32240278 PMCID: PMC7117665 DOI: 10.1371/journal.ppat.1008407] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 02/17/2020] [Indexed: 02/05/2023] Open
Abstract
Influenza A viruses are human pathogens with limited therapeutic options. Therefore, it is crucial to devise strategies for the identification of new classes of antiviral medications. The influenza A virus genome is constituted of 8 RNA segments. Two of these viral RNAs are transcribed into mRNAs that are alternatively spliced. The M1 mRNA encodes the M1 protein but is also alternatively spliced to yield the M2 mRNA during infection. M1 to M2 mRNA splicing occurs at nuclear speckles, and M1 and M2 mRNAs are exported to the cytoplasm for translation. M1 and M2 proteins are critical for viral trafficking, assembly, and budding. Here we show that gene knockout of the cellular protein NS1-BP, a constituent of the M mRNA speckle-export pathway and a binding partner of the virulence factor NS1 protein, inhibits M mRNA nuclear export without altering bulk cellular mRNA export, providing an avenue to preferentially target influenza virus. We performed a high-content, image-based chemical screen using single-molecule RNA-FISH to label viral M mRNAs followed by multistep quantitative approaches to assess cellular mRNA and cell toxicity. We identified inhibitors of viral mRNA biogenesis and nuclear export that exhibited no significant activity towards bulk cellular mRNA at non-cytotoxic concentrations. Among the hits is a small molecule that preferentially inhibits nuclear export of a subset of viral and cellular mRNAs without altering bulk cellular mRNA export. These findings underscore specific nuclear export requirements for viral mRNAs and phenocopy down-regulation of the mRNA export factor UAP56. This RNA export inhibitor impaired replication of diverse influenza A virus strains at non-toxic concentrations. Thus, this screening strategy yielded compounds that alone or in combination may serve as leads to new ways of treating influenza virus infection and are novel tools for studying viral RNA trafficking in the nucleus.
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Affiliation(s)
- Matthew Esparza
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Amir Mor
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Hanspeter Niederstrasser
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Kris White
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Alexander White
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Ke Zhang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Shengyan Gao
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Juan Wang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Jue Liang
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Sei Sho
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Ramanavelan Sakthivel
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Adwait A. Sathe
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Chao Xing
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Population and Data Sciences, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Raquel Muñoz-Moreno
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Jerry W. Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Joseph Ready
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Bruce Posner
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Beatriz M. A. Fontoura
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
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14
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Scott DD, Aguilar LC, Kramar M, Oeffinger M. It's Not the Destination, It's the Journey: Heterogeneity in mRNA Export Mechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1203:33-81. [PMID: 31811630 DOI: 10.1007/978-3-030-31434-7_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The process of creating a translation-competent mRNA is highly complex and involves numerous steps including transcription, splicing, addition of modifications, and, finally, export to the cytoplasm. Historically, much of the research on regulation of gene expression at the level of the mRNA has been focused on either the regulation of mRNA synthesis (transcription and splicing) or metabolism (translation and degradation). However, in recent years, the advent of new experimental techniques has revealed the export of mRNA to be a major node in the regulation of gene expression, and numerous large-scale and specific mRNA export pathways have been defined. In this chapter, we will begin by outlining the mechanism by which most mRNAs are homeostatically exported ("bulk mRNA export"), involving the recruitment of the NXF1/TAP export receptor by the Aly/REF and THOC5 components of the TREX complex. We will then examine various mechanisms by which this pathway may be controlled, modified, or bypassed in order to promote the export of subset(s) of cellular mRNAs, which include the use of metazoan-specific orthologs of bulk mRNA export factors, specific cis RNA motifs which recruit mRNA export machinery via specific trans-acting-binding factors, posttranscriptional mRNA modifications that act as "inducible" export cis elements, the use of the atypical mRNA export receptor, CRM1, and the manipulation or bypass of the nuclear pore itself. Finally, we will discuss major outstanding questions in the field of mRNA export heterogeneity and outline how cutting-edge experimental techniques are providing new insights into and tools for investigating the intriguing field of mRNA export heterogeneity.
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Affiliation(s)
- Daniel D Scott
- Institut de recherches cliniques de Montréal, Montréal, QC, Canada.,Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, Canada
| | | | - Mathew Kramar
- Institut de recherches cliniques de Montréal, Montréal, QC, Canada.,Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, Canada
| | - Marlene Oeffinger
- Institut de recherches cliniques de Montréal, Montréal, QC, Canada. .,Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, Canada. .,Faculté de Médecine, Département de Biochimie, Université de Montréal, Montréal, QC, Canada.
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15
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Garland W, Jensen TH. Nuclear sorting of RNA. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1572. [PMID: 31713323 DOI: 10.1002/wrna.1572] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/30/2019] [Accepted: 10/08/2019] [Indexed: 12/27/2022]
Abstract
The majority of the mammalian genome is transcribed by RNA polymerase II, yielding a vast amount of noncoding RNA (ncRNA) in addition to the standard production of mRNA. The typical nuclear biogenesis of mRNA relies on the tightly controlled coupling of co- and post-transcriptional processing events, which ultimately results in the export of transcripts into the cytoplasm. These processes are subject to surveillance by nuclear RNA decay pathways to prevent the export of aberrant, or otherwise "non-optimal," transcripts. However, unlike mRNA, many long ncRNAs are nuclear retained and those that maintain enduring functions must employ precautions to evade decay. Proper sorting and localization of RNA is therefore an essential activity in eukaryotic cells and the formation of ribonucleoprotein complexes during early stages of RNA synthesis is central to deciding such transcript fate. This review details our current understanding of the pathways and factors that direct RNAs towards a particular destiny and how transcripts combat the adverse conditions of the nucleus. 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)
- William Garland
- 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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16
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Chen Y, Belmont AS. Genome organization around nuclear speckles. Curr Opin Genet Dev 2019; 55:91-99. [PMID: 31394307 DOI: 10.1016/j.gde.2019.06.008] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 01/08/2023]
Abstract
Higher eukaryotic cell nuclei are highly compartmentalized into bodies and structural assemblies of specialized functions. Nuclear speckles/IGCs are one of the most prominent nuclear bodies, yet their functional significance remains largely unknown. Recent advances in sequence-based mapping of nuclear genome organization now provide genome-wide analysis of chromosome organization relative to nuclear speckles. Here we review older microscopy-based studies on a small number of genes with the new genomic mapping data suggesting a significant fraction of the genome is almost deterministically positioned near nuclear speckles. Both microscopy and genomic-based approaches support the concept of the nuclear speckle periphery as a major active chromosomal compartment which may play an important role in fine-tuning gene regulation.
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Affiliation(s)
- Yu Chen
- Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, CIRM Center of Excellence, University of California, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, Berkeley, CA 94720, USA
| | - Andrew S Belmont
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, B107 CLSL, 601 S. Goodwin Avenue, Urbana, IL 61801, USA.
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17
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Fan J, Kuai B, Wang K, Wang L, Wang Y, Wu X, Chi B, Li G, Cheng H. mRNAs are sorted for export or degradation before passing through nuclear speckles. Nucleic Acids Res 2019; 46:8404-8416. [PMID: 30032211 PMCID: PMC6144872 DOI: 10.1093/nar/gky650] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 07/10/2018] [Indexed: 12/14/2022] Open
Abstract
A significant fraction of mRNAs are degraded by the nuclear exosome in normal cells. Here, we studied where and when these exosome target mRNAs are sorted away from properly exported ones in the cells. We show that upon exosome inactivation, polyA RNAs are apparently accumulated in nuclear foci that are distinct from nuclear speckles (NSs), and provide several lines of evidence supporting that these polyA RNAs mainly correspond to accumulating exosome target mRNAs. These results suggest that exosomal mRNA degradation mostly occurs outside of NSs. In support of this possibility, targeting exosome target mRNAs to NSs stabilizes them by preventing exosomal degradation. Furthermore, inhibiting mRNA release from NSs does not attenuate exosomal degradation in normal cells, and results in polyA RNA accumulation both inside and outside of NSs in exosome inactivated cells, suggesting that passage through NSs is not required for sorting mRNAs for degradation or export. Indeed, exosome target mRNAs that normally do not enter NSs are exported upon exosome inactivation. Together, our data suggest that exosome target mRNAs are mainly degraded in the nucleoplasm before entering NSs and rapid removal of these mRNAs is important for preventing their nuclear export.
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Affiliation(s)
- Jing Fan
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Bin Kuai
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ke Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Lantian Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yimin Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xudong Wu
- Laboratory of Molecular Modeling and Design, State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Binkai Chi
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Guohui Li
- Laboratory of Molecular Modeling and Design, State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Hong Cheng
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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18
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Hochberg-Laufer H, Schwed-Gross A, Neugebauer KM, Shav-Tal Y. Uncoupling of nucleo-cytoplasmic RNA export and localization during stress. Nucleic Acids Res 2019; 47:4778-4797. [PMID: 30864659 PMCID: PMC6511838 DOI: 10.1093/nar/gkz168] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 02/26/2019] [Accepted: 03/02/2019] [Indexed: 12/25/2022] Open
Abstract
Eukaryotic cells contain sub-cellular compartments that are not membrane bound. Some structures are always present, such as nuclear speckles that contain RNA-binding proteins (RBPs) and poly(A)+ RNAs. Others, like cytoplasmic stress granules (SGs) that harbor mRNAs and RBPs, are induced upon stress. When we examined the formation and composition of nuclear speckles during stress induction with tubercidin, an adenosine analogue previously shown to affect nuclear speckle composition, we unexpectedly found that it also led to the formation of SGs and to the inhibition of several crucial steps of RNA metabolism in cells, thereby serving as a potent inhibitor of the gene expression pathway. Although transcription and splicing persisted under this stress, RBPs and mRNAs were mislocalized in the nucleus and cytoplasm. Specifically, lncRNA and RBP localization to nuclear speckles was disrupted, exon junction complex (EJC) recruitment to mRNA was reduced, mRNA export was obstructed, and cytoplasmic poly(A)+ RNAs localized in SGs. Furthermore, nuclear proteins that participate in mRNA export, such as nucleoporins and mRNA export adaptors, were mislocalized to SGs. This study reveals structural aspects of granule assembly in cells, and describes how the flow of RNA from the nucleus to the cytoplasm is severed under stress.
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Affiliation(s)
- Hodaya Hochberg-Laufer
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Avital Schwed-Gross
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Karla M Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06520, USA
| | - Yaron Shav-Tal
- The Mina & Everard Goodman Faculty of Life Sciences & Institute of Nanotechnology, Bar-Ilan University, Ramat Gan 5290002, Israel
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19
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Martins RP, Malbert-Colas L, Lista MJ, Daskalogianni C, Apcher S, Pla M, Findakly S, Blondel M, Fåhraeus R. Nuclear processing of nascent transcripts determines synthesis of full-length proteins and antigenic peptides. Nucleic Acids Res 2019; 47:3086-3100. [PMID: 30624716 PMCID: PMC6451098 DOI: 10.1093/nar/gky1296] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 11/23/2018] [Accepted: 12/18/2018] [Indexed: 01/19/2023] Open
Abstract
Peptides presented on major histocompatibility (MHC) class I molecules form an essential part of the immune system's capacity to detect virus-infected or transformed cells. Earlier works have shown that pioneer translation peptides (PTPs) for the MHC class I pathway are as efficiently produced from introns as from exons, or from mRNAs targeted for the nonsense-mediated decay pathway. The production of PTPs is a target for viral immune evasion but the underlying molecular mechanisms that govern this non-canonical translation are unknown. Here, we have used different approaches to show how events taking place on the nascent transcript control the synthesis of PTPs and full-length proteins. By controlling the subcellular interaction between the G-quadruplex structure (G4) of a gly-ala encoding mRNA and nucleolin (NCL) and by interfering with mRNA maturation using multiple approaches, we demonstrate that antigenic peptides derive from a nuclear non-canonical translation event that is independently regulated from the synthesis of full-length proteins. Moreover, we show that G4 are exploited to control mRNA localization and translation by distinguishable mechanisms that are targets for viral immune evasion.
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Affiliation(s)
| | | | - María José Lista
- Université de Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France
| | - Chrysoula Daskalogianni
- Université Paris 7, Inserm, UMR 1162, Paris, France
- ICCVS, University of Gdańsk, Science, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
| | - Sebastien Apcher
- Institut Gustave Roussy, Université Paris Sud, UMR 1015, Villejuif, France
| | - Marika Pla
- Université Paris 7, IUH, Inserm, UMR-S-1131, Paris, France
| | | | - Marc Blondel
- Université de Brest, Inserm, EFS, UMR 1078, GGB, F-29200 Brest, France
| | - Robin Fåhraeus
- Université Paris 7, Inserm, UMR 1162, Paris, France
- ICCVS, University of Gdańsk, Science, ul. Wita Stwosza 63, 80-308 Gdańsk, Poland
- Department of Medical Biosciences, Umeå University, Umeå, Sweden
- RECAMO, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic
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20
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Palazzo AF, Lee ES. Sequence Determinants for Nuclear Retention and Cytoplasmic Export of mRNAs and lncRNAs. Front Genet 2018; 9:440. [PMID: 30386371 PMCID: PMC6199362 DOI: 10.3389/fgene.2018.00440] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 09/14/2018] [Indexed: 11/26/2022] Open
Abstract
Eukaryotes are divided into two major compartments: the nucleus where RNA is synthesized and processed, and the cytoplasm, where mRNA is translated into proteins. Although many different RNAs are made, only a subset is allowed access to the cytoplasm, primarily RNAs involved in protein synthesis (mRNA, tRNA, and rRNA). In contrast, nuclear retained transcripts are mostly long non-coding RNAs (lncRNAs) whose role in cell physiology has been a source of much investigation in the past few years. In addition, it is likely that many non-functional RNAs, which arise by spurious transcription and misprocessing of functional RNAs, are also retained in the nucleus and degraded. In this review, the main sequence features that dictate whether any particular mRNA or lncRNA is a substrate for retention in the nucleus, or export to the cytoplasm, are discussed. Although nuclear export is promoted by RNA-splicing due to the fact that the spliceosome can help recruit export factors to the mature RNA, nuclear export does not require splicing. Indeed, most stable unspliced transcripts are well exported and associate with these same export factors in a splicing-independent manner. In contrast, nuclear retention is promoted by specialized cis-elements found in certain RNAs. This new understanding of the determinants of nuclear retention and cytoplasmic export provides a deeper understanding of how information flow is regulated in eukaryotic cells. Ultimately these processes promote the evolution of complexity in eukaryotes by shaping the genomic content through constructive neutral evolution.
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21
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Wang K, Wang L, Wang J, Chen S, Shi M, Cheng H. Intronless mRNAs transit through nuclear speckles to gain export competence. J Cell Biol 2018; 217:3912-3929. [PMID: 30194269 PMCID: PMC6219727 DOI: 10.1083/jcb.201801184] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 07/04/2018] [Accepted: 08/09/2018] [Indexed: 01/12/2023] Open
Abstract
Nuclear speckles (NSs) store splicing factors. Wang et al. show that many naturally intronless mRNAs associate with NSs and that speckle association enhances their export by facilitating TREX recruitment, suggesting that trafficking to NSs could be an important quality control step in intronless mRNA export. Nuclear speckles (NSs) serve as splicing factor storage sites. In this study, we unexpectedly found that many endogenous intronless mRNAs, which do not undergo splicing, associate with NSs. These associations do not require transcription, polyadenylation, or the polyA tail. Rather, exonic splicing enhancers present in intronless mRNAs and their binding partners, SR proteins, promote intronless mRNA localization to NSs. Significantly, speckle targeting of mRNAs promotes the recruitment of the TREX export complex and their TREX-dependent nuclear export. Furthermore, TREX, which accumulates in NSs, is required for releasing intronless mRNAs from NSs, whereas NXF1, which is mainly detected at nuclear pores, is not. Upon NXF1 depletion, the TREX protein UAP56 loses speckle concentration but coaccumulates with intronless mRNAs and polyA RNAs in the nucleoplasm, and these RNAs are trapped in NSs upon UAP56 codepletion. We propose that the export-competent messenger RNP assembly mainly occurs in NSs for intronless mRNAs and that entering NSs serves as a quality control step in mRNA export.
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Affiliation(s)
- Ke Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lantian Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Jianshu Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Suli Chen
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Min Shi
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Hong Cheng
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
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22
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Huang C, Liang D, Tatomer DC, Wilusz JE. A length-dependent evolutionarily conserved pathway controls nuclear export of circular RNAs. Genes Dev 2018; 32:639-644. [PMID: 29773557 PMCID: PMC6004072 DOI: 10.1101/gad.314856.118] [Citation(s) in RCA: 231] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 04/24/2018] [Indexed: 11/26/2022]
Abstract
Here, Huang et al. investigated how circRNA localization or nuclear export is controlled and, using RNAi screening, found that depletion of the Drosophila DExH/D-box helicase Hel25E results in nuclear accumulation of long (>800-nt), but not short, circRNAs. Their findings suggest that the lengths of mature circRNAs are measured to dictate the mode of nuclear export. Circular RNAs (circRNAs) are generated from many protein-coding genes. Most accumulate in the cytoplasm, but how circRNA localization or nuclear export is controlled remains unclear. Using RNAi screening, we found that depletion of the Drosophila DExH/D-box helicase Hel25E results in nuclear accumulation of long (>800-nucleotide), but not short, circRNAs. The human homologs of Hel25E similarly regulate circRNA localization, as depletion of UAP56 (DDX39B) or URH49 (DDX39A) causes long and short circRNAs, respectively, to become enriched in the nucleus. These data suggest that the lengths of mature circRNAs are measured to dictate the mode of nuclear export.
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Affiliation(s)
- Chuan Huang
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Dongming Liang
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Deirdre C Tatomer
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
| | - Jeremy E Wilusz
- Department of Biochemistry and Biophysics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
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23
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Microinjection and Fluorescence In Situ Hybridization Assay for Studying mRNA Export in Mammalian Cells. Methods Mol Biol 2017. [PMID: 28766292 DOI: 10.1007/978-1-4939-7204-3_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
Microinjection and Fluorescence in situ Hybridization (FISH) assay is a useful method for mRNA export studies, which can overcome the problems of traditional transfection in cells. Here, we describe the method of microinjection and FISH assay applied in investigation of mRNA export. By this method we can estimate the mRNA export kinetics, examining mRNA export in cells with low transfection efficiencies, and observing nuclear export of aberrant RNAs.
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24
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Lee ES, Palazzo AF. Assessing mRNA nuclear export in mammalian cells by microinjection. Methods 2017; 126:76-85. [DOI: 10.1016/j.ymeth.2017.05.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 05/23/2017] [Accepted: 05/29/2017] [Indexed: 11/17/2022] Open
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25
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Verbeeren J, Verma B, Niemelä EH, Yap K, Makeyev EV, Frilander MJ. Alternative exon definition events control the choice between nuclear retention and cytoplasmic export of U11/U12-65K mRNA. PLoS Genet 2017; 13:e1006824. [PMID: 28549066 PMCID: PMC5473595 DOI: 10.1371/journal.pgen.1006824] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 06/16/2017] [Accepted: 05/16/2017] [Indexed: 12/20/2022] Open
Abstract
Cellular homeostasis of the minor spliceosome is regulated by a negative feed-back loop that targets U11-48K and U11/U12-65K mRNAs encoding essential components of the U12-type intron-specific U11/U12 di-snRNP. This involves interaction of the U11 snRNP with an evolutionarily conserved splicing enhancer giving rise to unproductive mRNA isoforms. In the case of U11/U12-65K, this mechanism controls the length of the 3′ untranslated region (3′UTR). We show that this process is dynamically regulated in developing neurons and some other cell types, and involves a binary switch between translation-competent mRNAs with a short 3′UTR to non-productive isoforms with a long 3′UTR that are retained in the nucleus or/and spliced to the downstream amylase locus. Importantly, the choice between these alternatives is determined by alternative terminal exon definition events regulated by conserved U12- and U2-type 5′ splice sites as well as sequence signals used for pre-mRNA cleavage and polyadenylation. We additionally show that U11 snRNP binding to the U11/U12-65K mRNA species with a long 3′UTR is required for their nuclear retention. Together, our studies uncover an intricate molecular circuitry regulating the abundance of a key spliceosomal protein and shed new light on the mechanisms limiting the export of non-productively spliced mRNAs from the nucleus to the cytoplasm. The cellular homeostasis of many components of the eukaryotic RNA processing machinery is regulated via negative feed-back pathways that result in the formation of both productive and non-productive mRNA species. Typically, the formation of non-productive mRNAs species results from changes in alternative splicing that disrupt the reading frame of the protein coding region and leads to destabilization of the mRNA. Here, we have investigated the homeostasis regulation of the U11/U12-65K mRNA that encodes an essential protein component of the minor (U12-dependent) spliceosome intron recognition complex. We show that homeostasis is regulated at the level of nuclear mRNA export and mRNA 3′-end formation, and that it can be further regulated during neuronal differentiation. We describe a multilayered regulatory system utilizing alternative exon definition interactions that use the input from both spliceosomes and the polyadenylation machinery to decide between productive and non-productive mRNA formation. Because the 65K protein is an essential component of the minor spliceosome, this regulatory pathway can potentially affect the expression of ~700 genes containing U12-type introns.
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Affiliation(s)
- Jens Verbeeren
- Institute of Biotechnology, FI-00014 University of Helsinki, Helsinki, Finland
| | - Bhupendra Verma
- Institute of Biotechnology, FI-00014 University of Helsinki, Helsinki, Finland
| | - Elina H. Niemelä
- Institute of Biotechnology, FI-00014 University of Helsinki, Helsinki, Finland
| | - Karen Yap
- Centre for Developmental Neurobiology, King’s College London, London, United Kingdom
| | - Eugene V. Makeyev
- Centre for Developmental Neurobiology, King’s College London, London, United Kingdom
| | - Mikko J. Frilander
- Institute of Biotechnology, FI-00014 University of Helsinki, Helsinki, Finland
- * E-mail:
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26
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Woodward LA, Mabin JW, Gangras P, Singh G. The exon junction complex: a lifelong guardian of mRNA fate. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 8. [PMID: 28008720 DOI: 10.1002/wrna.1411] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/27/2016] [Accepted: 11/09/2016] [Indexed: 12/28/2022]
Abstract
During messenger RNA (mRNA) biogenesis and processing in the nucleus, many proteins are imprinted on mRNAs assembling them into messenger ribonucleoproteins (mRNPs). Some of these proteins remain stably bound within mRNPs and have a long-lasting impact on their fate. One of the best-studied examples is the exon junction complex (EJC), a multiprotein complex deposited primarily 24 nucleotides upstream of exon-exon junctions as a consequence of pre-mRNA splicing. The EJC maintains a stable, sequence-independent, hold on the mRNA until its removal during translation in the cytoplasm. Acting as a molecular shepherd, the EJC travels with mRNA across the cellular landscape coupling pre-mRNA splicing to downstream, posttranscriptional processes such as mRNA export, mRNA localization, translation, and nonsense-mediated mRNA decay (NMD). In this review, we discuss our current understanding of the EJC's functions during these processes, and expound its newly discovered functions (e.g., pre-mRNA splicing). Another focal point is the recently unveiled in vivo EJC interactome, which has shed new light on the EJC's location on the spliced RNAs and its intimate relationship with other mRNP components. We summarize new strides being made in connecting the EJC's molecular function with phenotypes, informed by studies of human disorders and model organisms. The progress toward understanding EJC functions has revealed, in its wake, even more questions, which are discussed throughout. WIREs RNA 2017, 8:e1411. doi: 10.1002/wrna.1411 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Lauren A Woodward
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Justin W Mabin
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Pooja Gangras
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
| | - Guramrit Singh
- Department of Molecular Genetics, The Ohio State University, Columbus, OH, USA
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27
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Palazzo AF, Truong M. Single particle imaging of mRNAs crossing the nuclear pore: Surfing on the edge. Bioessays 2016; 38:744-50. [DOI: 10.1002/bies.201600038] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
| | - Mathew Truong
- Department of Biochemistry; University of Toronto; Toronto ON Canada
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28
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Mor A, White A, Zhang K, Thompson M, Esparza M, Muñoz-Moreno R, Koide K, Lynch KW, García-Sastre A, Fontoura BM. Influenza virus mRNA trafficking through host nuclear speckles. Nat Microbiol 2016; 1:16069. [PMID: 27572970 PMCID: PMC4917225 DOI: 10.1038/nmicrobiol.2016.69] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Accepted: 04/20/2016] [Indexed: 12/26/2022]
Abstract
Influenza A virus is a human pathogen with a genome composed of eight viral RNA segments that replicate in the nucleus. Two viral mRNAs are alternatively spliced. The unspliced M1 mRNA is translated into the matrix M1 protein, while the ion channel M2 protein is generated after alternative splicing. These proteins are critical mediators of viral trafficking and budding. We show that the influenza virus uses nuclear speckles to promote post-transcriptional splicing of its M1 mRNA. We assign previously unknown roles for the viral NS1 protein and cellular factors to an intranuclear trafficking pathway that targets the viral M1 mRNA to nuclear speckles, mediates splicing at these nuclear bodies and exports the spliced M2 mRNA from the nucleus. Given that nuclear speckles are storage sites for splicing factors, which leave these sites to splice cellular pre-mRNAs at transcribing genes, we reveal a functional subversion of nuclear speckles to promote viral gene expression.
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Affiliation(s)
- Amir Mor
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9039, USA
| | - Alexander White
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9039, USA
| | - Ke Zhang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9039, USA
| | - Matthew Thompson
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6059, USA
| | - Matthew Esparza
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9039, USA
| | - Raquel Muñoz-Moreno
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Kazunori Koide
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Kristen W. Lynch
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6059, USA
| | - Adolfo García-Sastre
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
- Department of Medicine, Division of Infectious Diseases, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Beatriz M.A. Fontoura
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9039, USA
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Akef A, Lee ES, Palazzo AF. Splicing promotes the nuclear export of β-globin mRNA by overcoming nuclear retention elements. RNA (NEW YORK, N.Y.) 2015; 21:1908-20. [PMID: 26362019 PMCID: PMC4604431 DOI: 10.1261/rna.051987.115] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 07/20/2015] [Indexed: 05/14/2023]
Abstract
Most current models of mRNA nuclear export in vertebrate cells assume that an mRNA must have specialized signals in order to be exported from the nucleus. Under such a scenario, mRNAs that lack these specialized signals would be shunted into a default pathway where they are retained in the nucleus and eventually degraded. These ideas were based on the selective use of model mRNA reporters. For example, it has been shown that splicing promotes the nuclear export of certain model mRNAs, such as human β-globin, and that in the absence of splicing, the cDNA-derived mRNA is retained in the nucleus and degraded. Here we provide evidence that β-globin mRNA contains an element that actively retains it in the nucleus and degrades it. Interestingly, this nuclear retention activity can be overcome by increasing the length of the mRNA or by splicing. Our results suggest that contrary to many current models, the default pathway for most intronless RNAs is to be exported from the nucleus, unless the RNA contains elements that actively promote its nuclear retention.
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Affiliation(s)
- Abdalla Akef
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Eliza S Lee
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Alexander F Palazzo
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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Lee ES, Akef A, Mahadevan K, Palazzo AF. The consensus 5' splice site motif inhibits mRNA nuclear export. PLoS One 2015; 10:e0122743. [PMID: 25826302 PMCID: PMC4380460 DOI: 10.1371/journal.pone.0122743] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2014] [Accepted: 02/12/2015] [Indexed: 11/19/2022] Open
Abstract
In eukaryotes, mRNAs are synthesized in the nucleus and then exported to the cytoplasm where they are translated into proteins. We have mapped an element, which when present in the 3’terminal exon or in an unspliced mRNA, inhibits mRNA nuclear export. This element has the same sequence as the consensus 5’splice site motif that is used to define the start of introns. Previously it was shown that when this motif is retained in the mRNA, it causes defects in 3’cleavage and polyadenylation and promotes mRNA decay. Our new data indicates that this motif also inhibits nuclear export and promotes the targeting of transcripts to nuclear speckles, foci within the nucleus which have been linked to splicing. The motif, however, does not disrupt splicing or the recruitment of UAP56 or TAP/Nxf1 to the RNA, which are normally required for nuclear export. Genome wide analysis of human mRNAs, lncRNA and eRNAs indicates that this motif is depleted from naturally intronless mRNAs and eRNAs, but less so in lncRNAs. This motif is also depleted from the beginning and ends of the 3’terminal exons of spliced mRNAs, but less so for lncRNAs. Our data suggests that the presence of the 5’splice site motif in mature RNAs promotes their nuclear retention and may help to distinguish mRNAs from misprocessed transcripts and transcriptional noise.
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Affiliation(s)
- Eliza S. Lee
- Department of Biochemistry, University of Toronto, 1 King’s College Circle, MSB Room 5336, Toronto, ON, M5S 1A8, Canada
| | - Abdalla Akef
- Department of Biochemistry, University of Toronto, 1 King’s College Circle, MSB Room 5336, Toronto, ON, M5S 1A8, Canada
| | - Kohila Mahadevan
- Department of Biochemistry, University of Toronto, 1 King’s College Circle, MSB Room 5336, Toronto, ON, M5S 1A8, Canada
| | - Alexander F. Palazzo
- Department of Biochemistry, University of Toronto, 1 King’s College Circle, MSB Room 5336, Toronto, ON, M5S 1A8, Canada
- * E-mail:
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Palazzo AF, Lee ES. Non-coding RNA: what is functional and what is junk? Front Genet 2015; 6:2. [PMID: 25674102 PMCID: PMC4306305 DOI: 10.3389/fgene.2015.00002] [Citation(s) in RCA: 501] [Impact Index Per Article: 55.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 01/06/2015] [Indexed: 12/12/2022] Open
Abstract
The genomes of large multicellular eukaryotes are mostly comprised of non-protein coding DNA. Although there has been much agreement that a small fraction of these genomes has important biological functions, there has been much debate as to whether the rest contributes to development and/or homeostasis. Much of the speculation has centered on the genomic regions that are transcribed into RNA at some low level. Unfortunately these RNAs have been arbitrarily assigned various names, such as “intergenic RNA,” “long non-coding RNAs” etc., which have led to some confusion in the field. Many researchers believe that these transcripts represent a vast, unchartered world of functional non-coding RNAs (ncRNAs), simply because they exist. However, there are reasons to question this Panglossian view because it ignores our current understanding of how evolution shapes eukaryotic genomes and how the gene expression machinery works in eukaryotic cells. Although there are undoubtedly many more functional ncRNAs yet to be discovered and characterized, it is also likely that many of these transcripts are simply junk. Here, we discuss how to determine whether any given ncRNA has a function. Importantly, we advocate that in the absence of any such data, the appropriate null hypothesis is that the RNA in question is junk.
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Affiliation(s)
| | - Eliza S Lee
- Department of Biochemistry, University of Toronto Toronto, ON, Canada
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Niedojadło J, Kubicka E, Kalich B, Smoliński DJ. Poly(A) RNAs including coding proteins RNAs occur in plant Cajal bodies. PLoS One 2014; 9:e111780. [PMID: 25369024 PMCID: PMC4219776 DOI: 10.1371/journal.pone.0111780] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 10/05/2014] [Indexed: 11/19/2022] Open
Abstract
The localisation of poly(A) RNA in plant cells containing either reticular (Allium cepa) or chromocentric (Lupinus luteus, Arabidopsis thaliana) nuclei was studied through in situ hybridisation. In both types of nuclei, the amount of poly(A) RNA was much greater in the nucleus than in the cytoplasm. In the nuclei, poly(A) RNA was present in structures resembling nuclear bodies. The molecular composition as well as the characteristic ultrastructure of the bodies containing poly(A) RNA demonstrated that they were Cajal bodies. We showed that some poly(A) RNAs in Cajal bodies code for proteins. However, examination of the localisation of active RNA polymerase II and in situ run-on transcription assays both demonstrated that CBs are not sites of transcription and that BrU-containing RNA accumulates in these structures long after synthesis. In addition, it was demonstrated that accumulation of poly(A) RNA occurs in the nuclei and CBs of hypoxia-treated cells. Our findings indicated that CBs may be involved in the later stages of poly(A) RNA metabolism, playing a role storage or retention.
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Affiliation(s)
- Janusz Niedojadło
- Department of Cell Biology, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Torun, Poland
- * E-mail:
| | - Ewa Kubicka
- Department of Cell Biology, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Torun, Poland
| | - Beata Kalich
- Department of Cell Biology, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Torun, Poland
| | - Dariusz J. Smoliński
- Department of Cell Biology, Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Torun, Poland
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Sumoylation is Required for the Cytoplasmic Accumulation of a Subset of mRNAs. Genes (Basel) 2014; 5:982-1000. [PMID: 25333844 PMCID: PMC4276922 DOI: 10.3390/genes5040982] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/26/2014] [Accepted: 10/04/2014] [Indexed: 12/17/2022] Open
Abstract
In order to discover novel proteins that promote the nuclear export of newly synthesized mRNAs in mammalian cells, we carried out a limited RNAi screen for proteins required for the proper cytoplasmic distribution of a model intronless mRNA. From this screen we obtained two hits, Ubc9 (SUMO-conjugating E2 enzyme) and GANP (germinal center-associated nuclear protein). Depletion of Ubc9 inhibited the proper cytoplasmic distribution of certain overexpressed intronless mRNAs, while depletion of GANP affected all tested mRNAs. Depletion of Sae1, which is also required for sumoylation, partially inhibited the cytoplasmic distribution of our model mRNA. Interestingly, the block in cytoplasmic accumulation in Ubc9-depleted cells could be overcome if an intron was incorporated into the mRNA. Surprisingly, Ubc9-depleted cells had normal nuclear export of newly synthesized intronless mRNAs, indicating that the observed accumulation of the model mRNA in the nuclei of transfected cells was likely due to some more general perturbation. Indeed, depletion of Ubc9, coupled with the overexpression of the intronless mRNAs, caused the redistribution of the nuclear speckle protein SC35 to cytoplasmic foci. Our results suggest that sumoylation may play a role in the proper assembly of mRNPs and/or the distribution of key RNA binding proteins, and may thus contribute to general protein expression patterns.
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Cau P, Navarro C, Harhouri K, Roll P, Sigaudy S, Kaspi E, Perrin S, De Sandre-Giovannoli A, Lévy N. WITHDRAWN: Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective. Semin Cell Dev Biol 2014:S1084-9521(14)00058-5. [PMID: 24685615 DOI: 10.1016/j.semcdb.2014.03.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 03/03/2014] [Accepted: 03/09/2014] [Indexed: 10/25/2022]
Abstract
The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.semcdb.2014.03.022. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Affiliation(s)
- Pierre Cau
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(2).
| | - Claire Navarro
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1)
| | - Karim Harhouri
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1)
| | - Patrice Roll
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(2)
| | - Sabine Sigaudy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(3)
| | - Elise Kaspi
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(2)
| | - Sophie Perrin
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1)
| | - Annachiara De Sandre-Giovannoli
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(3)
| | - Nicolas Lévy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France(1); AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France(3).
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Cau P, Navarro C, Harhouri K, Roll P, Sigaudy S, Kaspi E, Perrin S, De Sandre-Giovannoli A, Lévy N. Nuclear matrix, nuclear envelope and premature aging syndromes in a translational research perspective. Semin Cell Dev Biol 2014; 29:125-47. [PMID: 24662892 DOI: 10.1016/j.semcdb.2014.03.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Lamin A-related progeroid syndromes are genetically determined, extremely rare and severe. In the past ten years, our knowledge and perspectives for these diseases has widely progressed, through the progressive dissection of their pathophysiological mechanisms leading to precocious and accelerated aging, from the genes mutations discovery until therapeutic trials in affected children. A-type lamins are major actors in several structural and functional activities at the nuclear periphery, as they are major components of the nuclear lamina. However, while this is usually poorly considered, they also play a key role within the rest of the nucleoplasm, whose defects are related to cell senescence. Although nuclear shape and nuclear envelope deformities are obvious and visible events, nuclear matrix disorganization and abnormal composition certainly represent the most important causes of cell defects with dramatic pathological consequences. Therefore, lamin-associated diseases should be better referred as laminopathies instead of envelopathies, this later being too restrictive, considering neither the key structural and functional roles of soluble lamins in the entire nucleoplasm, nor the nuclear matrix contribution to the pathophysiology of lamin-associated disorders and in particular in defective lamin A processing-associated aging diseases. Based on both our understanding of pathophysiological mechanisms and the biological and clinical consequences of progeria and related diseases, therapeutic trials have been conducted in patients and were terminated less than 10 years after the gene discovery, a quite fast issue for a genetic disease. Pharmacological drugs have been repurposed and used to decrease the toxicity of the accumulated, unprocessed and truncated prelaminA in progeria. To date, none of them may be considered as a cure for progeria and these clinical strategies were essentially designed toward reducing a subset of the most dramatic and morbid features associated to progeria. New therapeutic strategies under study, in particular targeting the protein expression pathway at the mRNA level, have shown a remarkable efficacy both in vitro in cells and in vivo in mice models. Strategies intending to clear the toxic accumulated proteins from the nucleus are also under evaluation. However, although exceedingly rare, improving our knowledge of genetic progeroid syndromes and searching for innovative and efficient therapies in these syndromes is of paramount importance as, even before they can be used to save lives, they may significantly (i) expand the affected childrens' lifespan and preserve their quality of life; (ii) improve our understanding of aging-related disorders and other more common diseases; and (iii) expand our fundamental knowledge of physiological aging and its links with major physiological processes such as those involved in oncogenesis.
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Affiliation(s)
- Pierre Cau
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France.
| | - Claire Navarro
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Karim Harhouri
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Patrice Roll
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Sabine Sigaudy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Elise Kaspi
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Service de Biologie Cellulaire, Hôpital La Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Sophie Perrin
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France
| | - Annachiara De Sandre-Giovannoli
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France
| | - Nicolas Lévy
- Aix-Marseille Université, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; INSERM, UMR_S 910, Génétique Médicale et Génomique Fonctionnelle, Faculté de Médecine, 27 Bd Jean Moulin, 13385 Marseille Cedex 5, France; AP-HM, Département de Génétique Médicale, Hôpital d'enfants Timone, 264 Rue Saint Pierre, 13385 Marseille Cedex 5, France.
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Riedmann EM. Landes Highlights. RNA Biol 2013. [DOI: 10.4161/rna.26373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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