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Reis-Claro I, Silva MI, Moutinho A, Garcia BC, Pereira-Castro I, Moreira A. Application of the iPLUS non-coding sequence in improving biopharmaceuticals production. Front Bioeng Biotechnol 2024; 12:1355957. [PMID: 38380261 PMCID: PMC10876878 DOI: 10.3389/fbioe.2024.1355957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 01/25/2024] [Indexed: 02/22/2024] Open
Abstract
The biotechnological landscape has witnessed significant growth in biological therapeutics particularly in the field of recombinant protein production. Here we investigate the function of 3'UTR cis-regulatory elements in increasing mRNA and protein levels in different biological therapeutics and model systems, spanning from monoclonal antibodies to mRNA vaccines. We explore the regulatory function of iPLUS - a universal sequence capable of consistently augmenting recombinant protein levels. By incorporating iPLUS in a vector to express a monoclonal antibody used in immunotherapy, in a mammalian cell line used by the industry (ExpiCHO), trastuzumab production increases by 2-fold. As yeast Pichia pastoris is widely used in the manufacture of industrial enzymes and pharmaceuticals, we then used iPLUS in tandem (3x) and iPLUSv2 (a variant of iPLUS) to provide proof-of-concept data that it increases the production of a reporter protein more than 100-fold. As iPLUS functions by also increasing mRNA levels, we hypothesize that these sequences could be used as an asset in the mRNA vaccine industry. In fact, by including iPLUSv2 downstream of Spike we were able to double its production. Moreover, the same effect was observed when we introduced iPLUSv2 downstream of MAGEC2, a tumor-specific antigen tested for cancer mRNA vaccines. Taken together, our study provides data (TLR4) showing that iPLUS may be used as a valuable asset in a variety of systems used by the biotech and biopharmaceutical industry. Our results underscore the critical role of non-coding sequences in controlling gene expression, offering a promising avenue to accelerate, enhance, and cost-effectively optimize biopharmaceutical production processes.
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Affiliation(s)
- Inês Reis-Claro
- Gene Regulation, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Maria Inês Silva
- Gene Regulation, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Ana Moutinho
- Gene Regulation, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Beatriz C. Garcia
- Gene Regulation, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Isabel Pereira-Castro
- Gene Regulation, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Alexandra Moreira
- Gene Regulation, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
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2
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Danckwardt S, Trégouët DA, Castoldi E. Post-transcriptional control of haemostatic genes: mechanisms and emerging therapeutic concepts in thrombo-inflammatory disorders. Cardiovasc Res 2023; 119:1624-1640. [PMID: 36943786 PMCID: PMC10325701 DOI: 10.1093/cvr/cvad046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 12/20/2022] [Accepted: 01/05/2023] [Indexed: 03/23/2023] Open
Abstract
The haemostatic system is pivotal to maintaining vascular integrity. Multiple components involved in blood coagulation have central functions in inflammation and immunity. A derailed haemostasis is common in prevalent pathologies such as sepsis, cardiovascular disorders, and lately, COVID-19. Physiological mechanisms limit the deleterious consequences of a hyperactivated haemostatic system through adaptive changes in gene expression. While this is mainly regulated at the level of transcription, co- and posttranscriptional mechanisms are increasingly perceived as central hubs governing multiple facets of the haemostatic system. This layer of regulation modulates the biogenesis of haemostatic components, for example in situations of increased turnover and demand. However, they can also be 'hijacked' in disease processes, thereby perpetuating and even causally entertaining associated pathologies. This review summarizes examples and emerging concepts that illustrate the importance of posttranscriptional mechanisms in haemostatic control and crosstalk with the immune system. It also discusses how such regulatory principles can be used to usher in new therapeutic concepts to combat global medical threats such as sepsis or cardiovascular disorders.
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Affiliation(s)
- Sven Danckwardt
- Centre for Thrombosis and Hemostasis (CTH), University Medical Centre
Mainz, Langenbeckstr. 1, 55131 Mainz, Germany
- German Centre for Cardiovascular Research (DZHK),
Berlin, Germany
- Posttranscriptional Gene Regulation, University Medical Centre
Mainz, Langenbeckstr. 1, 55131 Mainz, Germany
- Institute for Clinical Chemistry and Laboratory Medicine, University
Medical Centre Mainz, Langenbeckstr. 1, 55131
Mainz, Germany
- Center for Healthy Aging (CHA), Mainz,
Germany
| | - David-Alexandre Trégouët
- INSERM, Bordeaux Population Health Research Center, UMR 1219, Department of
Molecular Epidemiology of Vascular and Brain Disorders (ELEANOR), University of
Bordeaux, Bordeaux, France
| | - Elisabetta Castoldi
- Department of Biochemistry, Cardiovascular Research Institute Maastricht
(CARIM), Maastricht University, Universiteitsingel 50, 6229
ER Maastricht, The Netherlands
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3
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Rodríguez‐Molina JB, Turtola M. Birth of a poly(A) tail: mechanisms and control of mRNA polyadenylation. FEBS Open Bio 2023; 13:1140-1153. [PMID: 36416579 PMCID: PMC10315857 DOI: 10.1002/2211-5463.13528] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 11/17/2022] [Accepted: 11/22/2022] [Indexed: 11/24/2022] Open
Abstract
During their synthesis in the cell nucleus, most eukaryotic mRNAs undergo a two-step 3'-end processing reaction in which the pre-mRNA is cleaved and released from the transcribing RNA polymerase II and a polyadenosine (poly(A)) tail is added to the newly formed 3'-end. These biochemical reactions might appear simple at first sight (endonucleolytic RNA cleavage and synthesis of a homopolymeric tail), but their catalysis requires a multi-faceted enzymatic machinery, the cleavage and polyadenylation complex (CPAC), which is composed of more than 20 individual protein subunits. The activity of CPAC is further orchestrated by Poly(A) Binding Proteins (PABPs), which decorate the poly(A) tail during its synthesis and guide the mRNA through subsequent gene expression steps. Here, we review the structure, molecular mechanism, and regulation of eukaryotic mRNA 3'-end processing machineries with a focus on the polyadenylation step. We concentrate on the CPAC and PABPs from mammals and the budding yeast, Saccharomyces cerevisiae, because these systems are the best-characterized at present. Comparison of their functions provides valuable insights into the principles of mRNA 3'-end processing.
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Affiliation(s)
| | - Matti Turtola
- Department of Life TechnologiesUniversity of TurkuFinland
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4
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Cao J, Kuyumcu-Martinez MN. Alternative polyadenylation regulation in cardiac development and cardiovascular disease. Cardiovasc Res 2023; 119:1324-1335. [PMID: 36657944 PMCID: PMC10262186 DOI: 10.1093/cvr/cvad014] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 11/01/2022] [Accepted: 11/28/2022] [Indexed: 01/21/2023] Open
Abstract
Cleavage and polyadenylation of pre-mRNAs is a necessary step for gene expression and function. Majority of human genes exhibit multiple polyadenylation sites, which can be alternatively used to generate different mRNA isoforms from a single gene. Alternative polyadenylation (APA) of pre-mRNAs is important for the proteome and transcriptome landscape. APA is tightly regulated during development and contributes to tissue-specific gene regulation. Mis-regulation of APA is linked to a wide range of pathological conditions. APA-mediated gene regulation in the heart is emerging as a new area of research. Here, we will discuss the impact of APA on gene regulation during heart development and in cardiovascular diseases. First, we will briefly review how APA impacts gene regulation and discuss molecular mechanisms that control APA. Then, we will address APA regulation during heart development and its dysregulation in cardiovascular diseases. Finally, we will discuss pre-mRNA targeting strategies to correct aberrant APA patterns of essential genes for the treatment or prevention of cardiovascular diseases. The RNA field is blooming due to advancements in RNA-based technologies. RNA-based vaccines and therapies are becoming the new line of effective and safe approaches for the treatment and prevention of human diseases. Overall, this review will be influential for understanding gene regulation at the RNA level via APA in the heart and will help design RNA-based tools for the treatment of cardiovascular diseases in the future.
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Affiliation(s)
- Jun Cao
- Faculty of Environment and Life, Beijing University of Technology, Xueyuan Road, Haidian District, Beijing 100124, PR China
| | - Muge N Kuyumcu-Martinez
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77573, USA
- Department of Neurobiology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Institute for Translational Sciences, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77573, USA
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5
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Mitschka S, Mayr C. Context-specific regulation and function of mRNA alternative polyadenylation. Nat Rev Mol Cell Biol 2022; 23:779-796. [PMID: 35798852 PMCID: PMC9261900 DOI: 10.1038/s41580-022-00507-5] [Citation(s) in RCA: 148] [Impact Index Per Article: 49.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2022] [Indexed: 02/08/2023]
Abstract
Alternative cleavage and polyadenylation (APA) is a widespread mechanism to generate mRNA isoforms with alternative 3' untranslated regions (UTRs). The expression of alternative 3' UTR isoforms is highly cell type specific and is further controlled in a gene-specific manner by environmental cues. In this Review, we discuss how the dynamic, fine-grained regulation of APA is accomplished by several mechanisms, including cis-regulatory elements in RNA and DNA and factors that control transcription, pre-mRNA cleavage and post-transcriptional processes. Furthermore, signalling pathways modulate the activity of these factors and integrate APA into gene regulatory programmes. Dysregulation of APA can reprogramme the outcome of signalling pathways and thus can control cellular responses to environmental changes. In addition to the regulation of protein abundance, APA has emerged as a major regulator of mRNA localization and the spatial organization of protein synthesis. This role enables the regulation of protein function through the addition of post-translational modifications or the formation of protein-protein interactions. We further discuss recent transformative advances in single-cell RNA sequencing and CRISPR-Cas technologies, which enable the mapping and functional characterization of alternative 3' UTRs in any biological context. Finally, we discuss new APA-based RNA therapeutics, including compounds that target APA in cancer and therapeutic genome editing of degenerative diseases.
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Affiliation(s)
- Sibylle Mitschka
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Christine Mayr
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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6
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Spada S, Luke B, Danckwardt S. The Bidirectional Link Between RNA Cleavage and Polyadenylation and Genome Stability: Recent Insights From a Systematic Screen. Front Genet 2022; 13:854907. [PMID: 35571036 PMCID: PMC9095915 DOI: 10.3389/fgene.2022.854907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
The integrity of the genome is governed by multiple processes to ensure optimal survival and to prevent the inheritance of deleterious traits. While significant progress has been made to characterize components involved in the DNA Damage Response (DDR), little is known about the interplay between RNA processing and the maintenance of genome stability. Here, we describe the emerging picture of an intricate bidirectional coupling between RNA processing and genome integrity in an integrative manner. By employing insights from a recent large-scale RNAi screening involving the depletion of more than 170 components that direct (alternative) polyadenylation, we provide evidence of bidirectional crosstalk between co-transcriptional RNA 3′end processing and the DDR in a manner that optimizes genomic integrity. We provide instructive examples illustrating the wiring between the two processes and show how perturbations at one end are either compensated by buffering mechanisms at the other end, or even propel the initial insult and thereby become disease-eliciting as evidenced by various disorders.
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Affiliation(s)
- Stefano Spada
- Posttranscriptional Gene Regulation, University Medical Centre Mainz, Mainz, Germany
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Centre Mainz, Mainz, Germany
- Centre for Thrombosis and Hemostasis (CTH), University Medical Centre Mainz, Mainz, Germany
| | - Brian Luke
- Institute of Molecular Biology (IMB), Mainz, Germany
- Institute of Developmental Biology and Neurobiology (IDN), Johannes Gutenberg University, Mainz, Germany
| | - Sven Danckwardt
- Posttranscriptional Gene Regulation, University Medical Centre Mainz, Mainz, Germany
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Centre Mainz, Mainz, Germany
- Centre for Thrombosis and Hemostasis (CTH), University Medical Centre Mainz, Mainz, Germany
- German Centre for Cardiovascular Research (DZHK), Berlin, Germany
- Centre for Healthy Aging (CHA) Mainz, Mainz, Germany
- *Correspondence: Sven Danckwardt,
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7
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Pereira-Castro I, Garcia BC, Curinha A, Neves-Costa A, Conde-Sousa E, Moita LF, Moreira A. MCL1 alternative polyadenylation is essential for cell survival and mitochondria morphology. Cell Mol Life Sci 2022; 79:164. [PMID: 35229202 PMCID: PMC11072748 DOI: 10.1007/s00018-022-04172-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 01/07/2022] [Accepted: 01/27/2022] [Indexed: 02/02/2023]
Abstract
Alternative polyadenylation in the 3' UTR (3' UTR-APA) is a mode of gene expression regulation, fundamental for mRNA stability, translation and localization. In the immune system, it was shown that upon T cell activation, there is an increase in the relative expression of mRNA isoforms with short 3' UTRs resulting from 3' UTR-APA. However, the functional significance of 3' UTR-APA remains largely unknown. Here, we studied the physiological function of 3' UTR-APA in the regulation of Myeloid Cell Leukemia 1 (MCL1), an anti-apoptotic member of the Bcl-2 family essential for T cell survival. We found that T cells produce two MCL1 mRNA isoforms (pA1 and pA2) by 3' UTR-APA. We show that upon T cell activation, there is an increase in both the shorter pA1 mRNA isoform and MCL1 protein levels. Moreover, the less efficiently translated pA2 isoform is downregulated by miR-17, which is also more expressed upon T cell activation. Therefore, by increasing the expression of the more efficiently translated pA1 mRNA isoform, which escapes regulation by miR-17, 3' UTR-APA fine tunes MCL1 protein levels, critical for activated T cells' survival. Furthermore, using CRISPR/Cas9-edited cells, we show that depletion of either pA1 or pA2 mRNA isoforms causes severe defects in mitochondria morphology, increases apoptosis and impacts cell proliferation. Collectively, our results show that MCL1 alternative polyadenylation has a key role in the regulation of MCL1 protein levels upon T cell activation and reveal an essential function for MCL1 3' UTR-APA in cell viability and mitochondria dynamics.
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Affiliation(s)
- Isabel Pereira-Castro
- Gene Regulation, i3S, Instituto de Investigação E Inovação Em Saúde, Universidade Do Porto, Porto, Portugal.
- Gene Regulation, IBMC, Instituto de Biologia Molecular E Celular, Universidade Do Porto, Porto, Portugal.
| | - Beatriz C Garcia
- Gene Regulation, i3S, Instituto de Investigação E Inovação Em Saúde, Universidade Do Porto, Porto, Portugal
- Gene Regulation, IBMC, Instituto de Biologia Molecular E Celular, Universidade Do Porto, Porto, Portugal
| | - Ana Curinha
- Gene Regulation, IBMC, Instituto de Biologia Molecular E Celular, Universidade Do Porto, Porto, Portugal
- Department of Molecular Biology and Genetics, John Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Eduardo Conde-Sousa
- i3S, Instituto de Investigação E Inovação Em Saúde, Universidade Do Porto, Porto, Portugal
- INEB, Instituto de Engenharia Biomédica, Universidade Do Porto, Porto, Portugal
| | - Luís F Moita
- Instituto Gulbenkian de Ciência (IGC), Oeiras, Portugal
| | - Alexandra Moreira
- Gene Regulation, i3S, Instituto de Investigação E Inovação Em Saúde, Universidade Do Porto, Porto, Portugal.
- Gene Regulation, IBMC, Instituto de Biologia Molecular E Celular, Universidade Do Porto, Porto, Portugal.
- ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Universidade Do Porto, Porto, Portugal.
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8
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Beauregard AP, Hannay B, Gharib E, Crapoulet N, Finn N, Guerrette R, Ouellet A, Robichaud GA. Pax-5 Protein Expression Is Regulated by Transcriptional 3'UTR Editing. Cells 2021; 11:cells11010076. [PMID: 35011638 PMCID: PMC8750734 DOI: 10.3390/cells11010076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/16/2021] [Accepted: 12/21/2021] [Indexed: 02/07/2023] Open
Abstract
The Pax-5 gene encodes a transcription factor that is essential for B-cell commitment and maturation. However, Pax-5 deregulation is associated with various cancer lesions, notably hematopoietic cancers. Mechanistically, studies have characterized genetic alterations within the Pax-5 locus that result in either dominant oncogenic function or haploinsufficiency-inducing mutations leading to oncogenesis. Apart from these mutations, some examples of aberrant Pax-5 expression cannot be associated with genetic alterations. In the present study, we set out to elucidate potential alterations in post-transcriptional regulation of Pax-5 expression and establish that Pax-5 transcript editing represents an important means to aberrant expression. Upon the profiling of Pax-5 mRNA in leukemic cells, we found that the 3′end of the Pax-5 transcript is submitted to alternative polyadenylation (APA) and alternative splicing events. Using rapid amplification of cDNA ends (3′RACE) from polysomal fractions, we found that Pax-5 3′ untranslated region (UTR) shortening correlates with increased ribosomal occupancy for translation. These observations were also validated using reporter gene assays with truncated 3′UTR regions cloned downstream of a luciferase gene. We also showed that Pax-5 3′UTR editing has direct repercussions on regulatory elements such as miRNAs, which in turn impact Pax-5 protein expression. More importantly, we found that advanced staging of various hematopoietic cancer lesions relates to shorter Pax-5 3′UTRs. Altogether, our findings identify novel molecular mechanisms that account for aberrant expression and function of the Pax-5 oncogene in cancer cells. These findings also present new avenues for strategic intervention in Pax-5-mediated cancers.
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Affiliation(s)
- Annie-Pier Beauregard
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Atlantic Cancer Research Institute, Moncton, NB E1C 8X3, Canada
| | - Brandon Hannay
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Atlantic Cancer Research Institute, Moncton, NB E1C 8X3, Canada
| | - Ehsan Gharib
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Atlantic Cancer Research Institute, Moncton, NB E1C 8X3, Canada
| | - Nicolas Crapoulet
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Dr. Georges-L-Dumont University Hospital Centre, Moncton, NB E1C 8X3, Canada;
| | - Nicholas Finn
- Dr. Georges-L-Dumont University Hospital Centre, Moncton, NB E1C 8X3, Canada;
| | - Roxann Guerrette
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Atlantic Cancer Research Institute, Moncton, NB E1C 8X3, Canada
| | - Amélie Ouellet
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Atlantic Cancer Research Institute, Moncton, NB E1C 8X3, Canada
| | - Gilles A. Robichaud
- Department of Chemistry and Biochemistry, Université de Moncton, Moncton, NB E1A 3E9, Canada; (A.-P.B.); (B.H.); (E.G.); (N.C.); (R.G.); (A.O.)
- Atlantic Cancer Research Institute, Moncton, NB E1C 8X3, Canada
- Correspondence: ; Tel.: +1-(506)-858-4320
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9
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SFPQ rescues F508del-CFTR expression and function in cystic fibrosis bronchial epithelial cells. Sci Rep 2021; 11:16645. [PMID: 34404863 PMCID: PMC8371023 DOI: 10.1038/s41598-021-96141-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 08/05/2021] [Indexed: 01/19/2023] Open
Abstract
Cystic fibrosis (CF) occurs as a result of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to misfolding, trafficking defects, and impaired function of the CFTR protein. Splicing factor proline/glutamine-rich (SFPQ) is a multifunctional nuclear RNA-binding protein (RBP) implicated in the regulation of gene expression pathways and intracellular trafficking. Here, we investigated the role of SFPQ in the regulation of the expression and function of F508del-CFTR in CF lung epithelial cells. We find that the expression of SFPQ is reduced in F508del-CFTR CF epithelial cells compared to WT-CFTR control cells. Interestingly, the overexpression of SFPQ in CF cells increases the expression as well as rescues the function of F508del-CFTR. Further, comprehensive transcriptome analyses indicate that SFPQ plays a key role in activating the mutant F508del-CFTR by modulating several cellular signaling pathways. This is the first report on the role of SFPQ in the regulation of expression and function of F508del-CFTR in CF lung disease. Our findings provide new insights into SFPQ-mediated molecular mechanisms and point to possible novel epigenetic therapeutic targets for CF and related pulmonary diseases.
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10
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Shkurin A, Hughes TR. Known sequence features can explain half of all human gene ends. NAR Genom Bioinform 2021; 3:lqab042. [PMID: 34104882 PMCID: PMC8176999 DOI: 10.1093/nargab/lqab042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/14/2021] [Accepted: 05/10/2021] [Indexed: 11/15/2022] Open
Abstract
Cleavage and polyadenylation (CPA) sites define eukaryotic gene ends. CPA sites are associated with five key sequence recognition elements: the upstream UGUA, the polyadenylation signal (PAS), and U-rich sequences; the CA/UA dinucleotide where cleavage occurs; and GU-rich downstream elements (DSEs). Currently, it is not clear whether these sequences are sufficient to delineate CPA sites. Additionally, numerous other sequences and factors have been described, often in the context of promoting alternative CPA sites and preventing cryptic CPA site usage. Here, we dissect the contributions of individual sequence features to CPA using standard discriminative models. We show that models comprised only of the five primary CPA sequence features give highest probability scores to constitutive CPA sites at the ends of coding genes, relative to the entire pre-mRNA sequence, for 41% of all human genes. U1-hybridizing sequences provide a small boost in performance. The addition of all known RBP RNA binding motifs to the model, however, increases this figure to 49%, and suggests an involvement of both known and suspected CPA regulators as well as potential new factors in delineating constitutive CPA sites. To our knowledge, this high effectiveness of established features to predict human gene ends has not previously been documented.
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Affiliation(s)
- Aleksei Shkurin
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
- Terrence Donnelly Centre for Cellular & Biomolecular Research, Toronto, ON M5S 3E1, Canada
| | - Timothy R Hughes
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
- Terrence Donnelly Centre for Cellular & Biomolecular Research, Toronto, ON M5S 3E1, Canada
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11
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Pereira-Castro I, Moreira A. On the function and relevance of alternative 3'-UTRs in gene expression regulation. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 12:e1653. [PMID: 33843145 DOI: 10.1002/wrna.1653] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 12/12/2022]
Abstract
Messanger RNA (mRNA) isoforms with alternative 3'-untranslated regions (3'-UTRs) are produced by alternative polyadenylation (APA), which occurs during transcription in most eukaryotic genes. APA fine-tunes gene expression in a cell-type- and cellular state-dependent manner. Selection of an APA site entails the binding of core cleavage and polyadenylation factors to a particular polyadenylation site localized in the pre-mRNA and is controlled by multiple regulatory determinants, including transcription, pre-mRNA cis-regulatory sequences, and protein factors. Alternative 3'-UTRs serve as platforms for specific RNA binding proteins and microRNAs, which regulate gene expression in a coordinated manner by controlling mRNA fate and function in the cell. Genome-wide studies illustrated the full extent of APA prevalence and revealed that specific 3'-UTR profiles are associated with particular cellular states and diseases. Generally, short 3'-UTRs are associated with proliferative and cancer cells, and long 3'-UTRs are mostly found in polarized and differentiated cells. Fundamental new insights on the physiological consequences of this widespread event and the molecular mechanisms involved have been revealed through single-cell studies. Publicly available comprehensive databases that cover all APA mRNA isoforms identified in many cellular states and diseases reveal specific APA signatures. Therapies tackling APA mRNA isoforms or APA regulators may be regarded as innovative and attractive tools for diagnostics or treatment of several pathologies. We highlight the function of APA and alternative 3'-UTRs in gene expression regulation, the control of these mechanisms, their physiological consequences, and their potential use as new biomarkers and therapeutic tools. This article is categorized under: RNA Processing > 3' End Processing RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Isabel Pereira-Castro
- Gene Regulation, i3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Alexandra Moreira
- Gene Regulation, i3S, Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC, Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
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12
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Long-read RNA sequencing of human and animal filarial parasites improves gene models and discovers operons. PLoS Negl Trop Dis 2020; 14:e0008869. [PMID: 33196647 PMCID: PMC7704054 DOI: 10.1371/journal.pntd.0008869] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 11/30/2020] [Accepted: 10/09/2020] [Indexed: 01/01/2023] Open
Abstract
Filarial parasitic nematodes (Filarioidea) cause substantial disease burden to humans and animals around the world. Recently there has been a coordinated global effort to generate, annotate, and curate genomic data from nematode species of medical and veterinary importance. This has resulted in two chromosome-level assemblies (Brugia malayi and Onchocerca volvulus) and 11 additional draft genomes from Filarioidea. These reference assemblies facilitate comparative genomics to explore basic helminth biology and prioritize new drug and vaccine targets. While the continual improvement of genome contiguity and completeness advances these goals, experimental functional annotation of genes is often hindered by poor gene models. Short-read RNA sequencing data and expressed sequence tags, in cooperation with ab initio prediction algorithms, are employed for gene prediction, but these can result in missing clade-specific genes, fragmented models, imperfect mapping of gene ends, and lack of isoform resolution. Long-read RNA sequencing can overcome these drawbacks and greatly improve gene model quality. Here, we present Iso-Seq data for B. malayi and Dirofilaria immitis, etiological agents of lymphatic filariasis and canine heartworm disease, respectively. These data cover approximately half of the known coding genomes and substantially improve gene models by extending untranslated regions, cataloging novel splice junctions from novel isoforms, and correcting mispredicted junctions. Furthermore, we validated computationally predicted operons, manually curated new operons, and merged fragmented gene models. We carried out analyses of poly(A) tails in both species, leading to the identification of non-canonical poly(A) signals. Finally, we prioritized and assessed known and putative anthelmintic targets, correcting or validating gene models for molecular cloning and target-based anthelmintic screening efforts. Overall, these data significantly improve the catalog of gene models for two important parasites, and they demonstrate how long-read RNA sequencing should be prioritized for ongoing improvement of parasitic nematode genome assemblies. Filarial parasitic nematodes are vector-borne parasites that infect humans and animals. Brugia malayi and Dirofilaria immitis are transmitted by mosquitoes and cause human lymphatic filariasis and canine heartworm disease, respectively. Recent years have seen a dramatic increase in genomic and transcriptomic data sets and the concomitant increase in innovative strategies for drug target identification, validation, and screening. However, while the completeness of genome assemblies of filarial parasitic nematodes has seen steady improvements, the reliability of gene models has not kept pace, hindering cloning efforts. Long-read RNA sequencing technologies are uniquely able to improve gene models, but have not been widely used for the causative agents of neglected tropical diseases. Here, we report the improvement of gene models in both B. malayi and D. immitis by long-read RNA sequencing. We identified novel operons, deprecated false positive operons, identified dozens of novel genes, and described the parameters of polyadenylation. We also focused on putative anthelmintic targets, identifying novel isoforms and correcting gene models. These data substantially increase the trustworthiness of gene models in these two species and demonstrate how long-read sequencing approaches should be prioritized in the continued improvement of genome assemblies and their gene annotations.
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13
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Warnasooriya C, Feeney CF, Laird KM, Ermolenko DN, Kielkopf CL. A splice site-sensing conformational switch in U2AF2 is modulated by U2AF1 and its recurrent myelodysplasia-associated mutation. Nucleic Acids Res 2020; 48:5695-5709. [PMID: 32343311 PMCID: PMC7261175 DOI: 10.1093/nar/gkaa293] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 04/09/2020] [Accepted: 04/17/2020] [Indexed: 02/02/2023] Open
Abstract
An essential heterodimer of the U2AF1 and U2AF2 pre-mRNA splicing factors nucleates spliceosome assembly at polypyrimidine (Py) signals preceding the major class of 3′ splice sites. U2AF1 frequently acquires an S34F-encoding mutation among patients with myelodysplastic syndromes (MDS). The influence of the U2AF1 subunit and its S34F mutation on the U2AF2 conformations remains unknown. Here, we employ single molecule Förster resonance energy transfer (FRET) to determine the influence of wild-type or S34F-substituted U2AF1 on the conformational dynamics of U2AF2 and its splice site RNA complexes. In the absence of RNA, the U2AF1 subunit stabilizes a high FRET value, which by structure-guided mutagenesis corresponds to a closed conformation of the tandem U2AF2 RNA recognition motifs (RRMs). When the U2AF heterodimer is bound to a strong, uridine-rich splice site, U2AF2 switches to a lower FRET value characteristic of an open, side-by-side arrangement of the RRMs. Remarkably, the U2AF heterodimer binds weak, uridine-poor Py tracts as a mixture of closed and open U2AF2 conformations, which are modulated by the S34F mutation. Shifts between open and closed U2AF2 may underlie U2AF1-dependent splicing of degenerate Py tracts and contribute to a subset of S34F-dysregulated splicing events in MDS patients.
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Affiliation(s)
- Chandani Warnasooriya
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Callen F Feeney
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Kholiswa M Laird
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Dmitri N Ermolenko
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Clara L Kielkopf
- Department of Biochemistry and Biophysics and Center for RNA Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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14
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Nourse J, Spada S, Danckwardt S. Emerging Roles of RNA 3'-end Cleavage and Polyadenylation in Pathogenesis, Diagnosis and Therapy of Human Disorders. Biomolecules 2020; 10:biom10060915. [PMID: 32560344 PMCID: PMC7356254 DOI: 10.3390/biom10060915] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 06/10/2020] [Accepted: 06/13/2020] [Indexed: 12/11/2022] Open
Abstract
A crucial feature of gene expression involves RNA processing to produce 3′ ends through a process termed 3′ end cleavage and polyadenylation (CPA). This ensures the nascent RNA molecule can exit the nucleus and be translated to ultimately give rise to a protein which can execute a function. Further, alternative polyadenylation (APA) can produce distinct transcript isoforms, profoundly expanding the complexity of the transcriptome. CPA is carried out by multi-component protein complexes interacting with multiple RNA motifs and is tightly coupled to transcription, other steps of RNA processing, and even epigenetic modifications. CPA and APA contribute to the maintenance of a multitude of diverse physiological processes. It is therefore not surprising that disruptions of CPA and APA can lead to devastating disorders. Here, we review potential CPA and APA mechanisms involving both loss and gain of function that can have tremendous impacts on health and disease. Ultimately we highlight the emerging diagnostic and therapeutic potential CPA and APA offer.
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Affiliation(s)
- Jamie Nourse
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany; (J.N.); (S.S.)
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
| | - Stefano Spada
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany; (J.N.); (S.S.)
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
| | - Sven Danckwardt
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany; (J.N.); (S.S.)
- Center for Thrombosis and Hemostasis (CTH), University Medical Center of the Johannes Gutenberg University, 55131 Mainz, Germany
- German Center for Cardiovascular Research (DZHK), Rhine-Main, Germany
- Correspondence:
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15
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BCL-w: apoptotic and non-apoptotic role in health and disease. Cell Death Dis 2020; 11:260. [PMID: 32317622 PMCID: PMC7174325 DOI: 10.1038/s41419-020-2417-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 03/18/2020] [Accepted: 03/19/2020] [Indexed: 12/17/2022]
Abstract
The BCL-2 family of proteins integrates signals that trigger either cell survival or apoptosis. The balance between pro-survival and pro-apoptotic proteins is important for tissue development and homeostasis, while impaired apoptosis contributes to several pathologies and can be a barrier against effective treatment. BCL-w is an anti-apoptotic protein that shares a sequence similarity with BCL-XL, and exhibits a high conformational flexibility. BCL-w level is controlled by a number of signaling pathways, and the repertoire of transcriptional regulators largely depends on the cellular and developmental context. As only a few disease-relevant genetic alterations of BCL2L2 have been identified, increased levels of BCL-w might be a consequence of abnormal activation of signaling cascades involved in the regulation of BCL-w expression. In addition, BCL-w transcript is a target of a plethora of miRNAs. Besides its originally recognized pro-survival function during spermatogenesis, BCL-w has been envisaged in different types of normal and diseased cells as an anti-apoptotic protein. BCL-w contributes to survival of senescent and drug-resistant cells. Its non-apoptotic role in the promotion of cell migration and invasion has also been elucidated. Growing evidence indicates that a high BCL-w level can be therapeutically relevant in neurodegenerative disorders, neuron dysfunctions and after small intestinal resection, whereas BCL-w inhibition can be beneficial for cancer patients. Although several drugs and natural compounds can bi-directionally affect BCL-w level, agents that selectively target BCL-w are not yet available. This review discusses current knowledge on the role of BCL-w in health, non-cancerous diseases and cancer.
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16
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Cell Cycle Kinase Polo Is Controlled by a Widespread 3' Untranslated Region Regulatory Sequence in Drosophila melanogaster. Mol Cell Biol 2019; 39:MCB.00581-18. [PMID: 31085682 DOI: 10.1128/mcb.00581-18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 05/04/2019] [Indexed: 01/06/2023] Open
Abstract
Alternative polyadenylation generates transcriptomic diversity, although the physiological impact and regulatory mechanisms involved are still poorly understood. The cell cycle kinase Polo is controlled by alternative polyadenylation in the 3' untranslated region (3'UTR), with critical physiological consequences. Here, we characterized the molecular mechanisms required for polo alternative polyadenylation. We identified a conserved upstream sequence element (USE) close to the polo proximal poly(A) signal. Transgenic flies without this sequence show incorrect selection of polo poly(A) signals with consequent downregulation of Polo expression levels and insufficient/defective activation of Polo kinetochore targets Mps1 and Aurora B. Deletion of the USE results in abnormal mitoses in neuroblasts, revealing a role for this sequence in vivo We found that Hephaestus binds to the USE RNA and that hephaestus mutants display defects in polo alternative polyadenylation concomitant with a striking reduction in Polo protein levels, leading to mitotic errors and aneuploidy. Bioinformatic analyses show that the USE is preferentially localized upstream of noncanonical polyadenylation signals in Drosophila melanogaster genes. Taken together, our results revealed the molecular mechanisms involved in polo alternative polyadenylation, with remarkable physiological functions in Polo expression and activity at the kinetochores, and disclosed a new in vivo function for USEs in Drosophila melanogaster.
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17
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Cheng JK, Morse NJ, Wagner JM, Tucker SK, Alper HS. Design and Evaluation of Synthetic Terminators for Regulating Mammalian Cell Transgene Expression. ACS Synth Biol 2019; 8:1263-1275. [PMID: 31091408 DOI: 10.1021/acssynbio.8b00285] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Tuning heterologous gene expression in mammalian production hosts has predominantly relied upon engineering the promoter elements driving the transcription of the transgene. Moreover, most regulatory elements have borrowed genetic sequences from viral elements. Here, we generate a set of 10 rational and 30 synthetic terminators derived from nonviral elements and evaluate them in the HT1080 and HEK293 cell lines to demonstrate that they are comparable in terms of tuning gene expression/protein output to the viral SV40 element and often require less sequence footprint. The mode of action of these terminators is determined to be an increase in mRNA half-life. Furthermore, we demonstrate that constructs comprising completely nonviral regulatory elements ( i.e., promoters and terminators) can outperform commonly used, strong viral based elements by nearly 2-fold. Ultimately, this novel set of terminators expanded our genetic toolkit for engineering mammalian host cells.
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Affiliation(s)
- Joseph K. Cheng
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton Street, Stop C0400, Austin, Texas 78712, United States
| | - Nicholas J. Morse
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton Street, Stop C0400, Austin, Texas 78712, United States
| | - James M. Wagner
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton Street, Stop C0400, Austin, Texas 78712, United States
| | - Scott K. Tucker
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2500 Speedway Avenue, Austin, Texas 78712, United States
| | - Hal S. Alper
- McKetta Department of Chemical Engineering, The University of Texas at Austin, 200 E Dean Keeton Street, Stop C0400, Austin, Texas 78712, United States
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, 2500 Speedway Avenue, Austin, Texas 78712, United States
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18
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Sadek J, Omer A, Hall D, Ashour K, Gallouzi IE. Alternative polyadenylation and the stress response. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 10:e1540. [DOI: 10.1002/wrna.1540] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 03/18/2019] [Accepted: 04/02/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Jason Sadek
- Department of Biochemistry McGill University, Rosalind and Morris Goodman Cancer Centre Montreal Quebec Canada
| | - Amr Omer
- Department of Biochemistry McGill University, Rosalind and Morris Goodman Cancer Centre Montreal Quebec Canada
| | - Derek Hall
- Department of Biochemistry McGill University, Rosalind and Morris Goodman Cancer Centre Montreal Quebec Canada
| | - Kholoud Ashour
- Department of Biochemistry McGill University, Rosalind and Morris Goodman Cancer Centre Montreal Quebec Canada
| | - Imed Eddine Gallouzi
- Department of Biochemistry McGill University, Rosalind and Morris Goodman Cancer Centre Montreal Quebec Canada
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19
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Yeh HS, Zhang W, Yong J. Analyses of alternative polyadenylation: from old school biochemistry to high-throughput technologies. BMB Rep 2018; 50:201-207. [PMID: 28148393 PMCID: PMC5437964 DOI: 10.5483/bmbrep.2017.50.4.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Indexed: 01/08/2023] Open
Abstract
Alternations in usage of polyadenylation sites during transcription termination yield transcript isoforms from a gene. Recent findings of transcriptome-wide alternative polyadenylation (APA) as a molecular response to changes in biology position APA not only as a molecular event of early transcriptional termination but also as a cellular regulatory step affecting various biological pathways. With the development of high-throughput profiling technologies at a single nucleotide level and their applications targeted to the 3'-end of mRNAs, dynamics in the landscape of mRNA 3'-end is measureable at a global scale. In this review, methods and technologies that have been adopted to study APA events are discussed. In addition, various bioinformatics algorithms for APA isoform analysis using publicly available RNA-seq datasets are introduced. [BMB Reports 2017; 50(4): 201-207].
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Affiliation(s)
- Hsin-Sung Yeh
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Wei Zhang
- Department of Computer Science and Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Jeongsik Yong
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, USA
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20
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Abstract
Ribonucleic acid (RNA) homeostasis is dynamically modulated in response to changing physiological conditions. Tight regulation of RNA abundance through both transcription and degradation determines the amount, timing, and location of protein translation. This balance is of particular importance in neurons, which are among the most metabolically active and morphologically complex cells in the body. As a result, any disruptions in RNA degradation can have dramatic consequences for neuronal health. In this chapter, we will first discuss mechanisms of RNA stabilization and decay. We will then explore how the disruption of these pathways can lead to neurodegenerative disease.
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21
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Neve J, Patel R, Wang Z, Louey A, Furger AM. Cleavage and polyadenylation: Ending the message expands gene regulation. RNA Biol 2017; 14:865-890. [PMID: 28453393 PMCID: PMC5546720 DOI: 10.1080/15476286.2017.1306171] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/02/2017] [Accepted: 03/09/2017] [Indexed: 12/13/2022] Open
Abstract
Cleavage and polyadenylation (pA) is a fundamental step that is required for the maturation of primary protein encoding transcripts into functional mRNAs that can be exported from the nucleus and translated in the cytoplasm. 3'end processing is dependent on the assembly of a multiprotein processing complex on the pA signals that reside in the pre-mRNAs. Most eukaryotic genes have multiple pA signals, resulting in alternative cleavage and polyadenylation (APA), a widespread phenomenon that is important to establish cell state and cell type specific transcriptomes. Here, we review how pA sites are recognized and comprehensively summarize how APA is regulated and creates mRNA isoform profiles that are characteristic for cell types, tissues, cellular states and disease.
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Affiliation(s)
- Jonathan Neve
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Radhika Patel
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Zhiqiao Wang
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Alastair Louey
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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22
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Ogorodnikov A, Kargapolova Y, Danckwardt S. Processing and transcriptome expansion at the mRNA 3' end in health and disease: finding the right end. Pflugers Arch 2016; 468:993-1012. [PMID: 27220521 PMCID: PMC4893057 DOI: 10.1007/s00424-016-1828-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 04/19/2016] [Indexed: 01/09/2023]
Abstract
The human transcriptome is highly dynamic, with each cell type, tissue, and organ system expressing an ensemble of transcript isoforms that give rise to considerable diversity. Apart from alternative splicing affecting the "body" of the transcripts, extensive transcriptome diversification occurs at the 3' end. Transcripts differing at the 3' end can have profound physiological effects by encoding proteins with distinct functions or regulatory properties or by affecting the mRNA fate via the inclusion or exclusion of regulatory elements (such as miRNA or protein binding sites). Importantly, the dynamic regulation at the 3' end is associated with various (patho)physiological processes, including the immune regulation but also tumorigenesis. Here, we recapitulate the mechanisms of constitutive mRNA 3' end processing and review the current understanding of the dynamically regulated diversity at the transcriptome 3' end. We illustrate the medical importance by presenting examples that are associated with perturbations of this process and indicate resulting implications for molecular diagnostics as well as potentially arising novel therapeutic strategies.
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Affiliation(s)
- Anton Ogorodnikov
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center Mainz, Langenbeckstr 1, 55131, Mainz, Germany
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Langenbeckstr 1, 55131, Mainz, Germany
| | - Yulia Kargapolova
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center Mainz, Langenbeckstr 1, 55131, Mainz, Germany
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Langenbeckstr 1, 55131, Mainz, Germany
| | - Sven Danckwardt
- Institute for Clinical Chemistry and Laboratory Medicine, University Medical Center Mainz, Langenbeckstr 1, 55131, Mainz, Germany.
- Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Langenbeckstr 1, 55131, Mainz, Germany.
- German Center for Cardiovascular Research (DZHK), Langenbeckstr 1, 55131, Mainz, Germany.
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23
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Cosker KE, Fenstermacher SJ, Pazyra-Murphy MF, Elliott HL, Segal RA. The RNA-binding protein SFPQ orchestrates an RNA regulon to promote axon viability. Nat Neurosci 2016; 19:690-696. [PMID: 27019013 PMCID: PMC5505173 DOI: 10.1038/nn.4280] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 03/01/2016] [Indexed: 12/20/2022]
Abstract
To achieve accurate spatiotemporal patterns of gene expression, RNA-binding proteins (RBPs) guide nuclear processing, intracellular trafficking and local translation of target mRNAs. In neurons, RBPs direct transport of target mRNAs to sites of translation in remote axons and dendrites. However, it is not known whether an individual RBP coordinately regulates multiple mRNAs within these morphologically complex cells. Here we identify SFPQ (splicing factor, poly-glutamine rich) as an RBP that binds and regulates multiple mRNAs in dorsal root ganglion sensory neurons and thereby promotes neurotrophin-dependent axonal viability. SFPQ acts in nuclei, cytoplasm and axons to regulate functionally related mRNAs essential for axon survival. Notably, SFPQ is required for coassembly of LaminB2 (Lmnb2) and Bclw (Bcl2l2) mRNAs in RNA granules and for axonal trafficking of these mRNAs. Together these data demonstrate that SFPQ orchestrates spatial gene expression of a newly identified RNA regulon essential for axonal viability.
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Affiliation(s)
- Katharina E Cosker
- Department of Neurobiology, Harvard Medical School, Department of Cancer
Biology, Dana-Farber Cancer Institute, Boston MA 02215, USA
| | - Sara J Fenstermacher
- Department of Neurobiology, Harvard Medical School, Department of Cancer
Biology, Dana-Farber Cancer Institute, Boston MA 02215, USA
| | - Maria F Pazyra-Murphy
- Department of Neurobiology, Harvard Medical School, Department of Cancer
Biology, Dana-Farber Cancer Institute, Boston MA 02215, USA
| | - Hunter L Elliott
- Image and Data Analysis Core, Harvard Medical School, Boston, MA 02115,
USA
| | - Rosalind A Segal
- Department of Neurobiology, Harvard Medical School, Department of Cancer
Biology, Dana-Farber Cancer Institute, Boston MA 02215, USA
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24
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Yeh HS, Yong J. Alternative Polyadenylation of mRNAs: 3'-Untranslated Region Matters in Gene Expression. Mol Cells 2016; 39:281-5. [PMID: 26912084 PMCID: PMC4844933 DOI: 10.14348/molcells.2016.0035] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 02/11/2016] [Indexed: 12/26/2022] Open
Abstract
Almost all of eukaryotic mRNAs are subjected to polyadenylation during mRNA processing. Recent discoveries showed that many of these mRNAs contain more than one polyadenylation sites in their 3' untranslated regions (UTR) and that alternative polyadenylation (APA) is prevalent among these genes. Many biological processes such as differentiation, proliferation, and tumorigenesis have been correlated to global APA events in the 3' UTR of mRNAs, suggesting that these APA events are tightly regulated and may play important physiological roles. In this review, recent discoveries in the physiological roles of APA events, as well as the known and proposed mechanisms are summarized. Perspective for future directions is also discussed.
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Affiliation(s)
- Hsin-Sung Yeh
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455,
USA
| | - Jeongsik Yong
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455,
USA
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25
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Duvignaud JB, Bédard M, Nagata T, Muto Y, Yokoyama S, Gagné SM, Vincent M. Structure, Dynamics, and Interaction of p54(nrb)/NonO RRM1 with 5' Splice Site RNA Sequence. Biochemistry 2016; 55:2553-66. [PMID: 27064654 DOI: 10.1021/acs.biochem.5b01240] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
p54(nrb)/NonO is a nuclear RNA-binding protein involved in many cellular events such as pre-mRNA processing, transcription, and nuclear retention of hyper-edited RNAs. In particular, it participates in the splicing process by directly binding the 5' splice site of pre-mRNAs. The protein also concentrates in a nuclear body called paraspeckle by binding a G-rich segment of the ncRNA NEAT1. The N-terminal section of p54(nrb)/NonO contains tandem RNA recognition motifs (RRMs) preceded by an HQ-rich region including a threonine residue (Thr15) whose phosphorylation inhibits its RNA binding ability, except for G-rich RNAs. In this work, our goal was to understand the rules that characterize the binding of the p54(nrb)/NonO RRMs to their RNA target. We have done in vitro RNA binding experiments which revealed that only the first RRM of p54(nrb)/NonO binds to the 5' splice site RNA. We have then determined the structure of the p54(nrb)/NonO RRM1 by liquid-state NMR which revealed the presence of a canonical fold (β1α1β2β3α2β4) and the conservation of aromatic amino acids at the protein surface. We also investigated the dynamics of this domain by NMR. The p54(nrb)/NonO RRM1 displays some motional properties that are typical of a well-folded protein with some regions exhibiting more flexibility (loops and β-strands). Furthermore, we determined the affinity of p54(nrb)/NonO RRM1 interaction to the 5' splice site RNA by NMR and fluorescence quenching and mapped its binding interface by NMR, concluding in a classical nucleic acid interaction. This study provides an improved understanding of the molecular basis (structure and dynamics) that governs the binding of the p54(nrb)/NonO RRM1 to one of its target RNAs.
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Affiliation(s)
| | | | - Takashi Nagata
- RIKEN Center for Life Science Technologies , Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yutaka Muto
- RIKEN Center for Life Science Technologies , Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.,Faculty of Pharmacy and Research Institute of Pharmaceutical Science, Musashino University , Nishitokyo-shi, Tokyo 202-8585, Japan
| | - Shigeyuki Yokoyama
- RIKEN Systems and Structural Biology Center , 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.,RIKEN Structural Biology Laboratory , 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
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26
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Domingues RG, Lago-Baldaia I, Pereira-Castro I, Fachini JM, Oliveira L, Drpic D, Lopes N, Henriques T, Neilson JR, Carmo AM, Moreira A. CD5 expression is regulated during human T-cell activation by alternative polyadenylation, PTBP1, and miR-204. Eur J Immunol 2016; 46:1490-503. [PMID: 27005442 DOI: 10.1002/eji.201545663] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 02/17/2016] [Accepted: 03/16/2016] [Indexed: 01/29/2023]
Abstract
T lymphocytes stimulated through their antigen receptor (TCR) preferentially express mRNA isoforms with shorter 3´ untranslated regions (3´-UTRs) derived from alternative pre-mRNA cleavage and polyadenylation (APA). However, the physiological relevance of APA programs remains poorly understood. CD5 is a T-cell surface glycoprotein that negatively regulates TCR signaling from the onset of T-cell activation. CD5 plays a pivotal role in mediating outcomes of cell survival or apoptosis, and may prevent both autoimmunity and cancer. In human primary T lymphocytes and Jurkat cells we found three distinct mRNA isoforms encoding CD5, each derived from distinct poly(A) signals (PASs). Upon T-cell activation, there is an overall increase in CD5 mRNAs with a specific increase in the relative expression of the shorter isoforms. 3´-UTRs derived from these shorter isoforms confer higher reporter expression in activated T cells relative to the longer isoform. We further show that polypyrimidine tract binding protein (PTB/PTBP1) directly binds to the proximal PAS and PTB siRNA depletion causes a decrease in mRNA derived from this PAS, suggesting an effect on stability or poly(A) site selection to circumvent targeting of the longer CD5 mRNA isoform by miR-204. These mechanisms fine-tune CD5 expression levels and thus ultimately T-cell responses.
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Affiliation(s)
- Rita G Domingues
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Inês Lago-Baldaia
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Isabel Pereira-Castro
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.,Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
| | - Joseph M Fachini
- Department of Molecular Physiology and Biophysics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Liliana Oliveira
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,Cell Activation and Gene Expression Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Danica Drpic
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.,Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
| | - Nair Lopes
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Telmo Henriques
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal
| | - Joel R Neilson
- Department of Molecular Physiology and Biophysics, Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Alexandre M Carmo
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,Cell Activation and Gene Expression Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.,ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Portugal
| | - Alexandra Moreira
- Gene Regulation Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Portugal.,Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.,ICBAS - Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Portugal
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27
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Huang G, Huang S, Wang R, Yan X, Li Y, Feng Y, Wang S, Yang X, Chen L, Li J, You L, Chen S, Luo G, Xu A. Dynamic Regulation of Tandem 3' Untranslated Regions in Zebrafish Spleen Cells during Immune Response. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2016; 196:715-725. [PMID: 26673144 DOI: 10.4049/jimmunol.1500847] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 11/08/2015] [Indexed: 12/24/2022]
Abstract
Alternative polyadenylation (APA) has been found to be involved in tumorigenesis, development, and cell differentiation, as well as in the activation of several subsets of immune cells in vitro. Whether APA takes place in immune responses in vivo is largely unknown. We profiled the variation in tandem 3' untranslated regions (UTRs) in pathogen-challenged zebrafish and identified hundreds of APA genes with ∼ 10% being immune response genes. The detected immune response APA genes were enriched in TLR signaling, apoptosis, and JAK-STAT signaling pathways. A greater number of microRNA target sites and AU-rich elements were found in the extended 3' UTRs than in the common 3' UTRs of these APA genes. Further analysis suggested that microRNA and AU-rich element-mediated posttranscriptional regulation plays an important role in modulating the expression of APA genes. These results indicate that APA is extensively involved in immune responses in vivo, and it may be a potential new paradigm for immune regulation.
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Affiliation(s)
- Guangrui Huang
- School of Basic Medical Sciences, Beijing University of Chinese Medicine, Beijing 100029, People's Republic of China; State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106
| | - Shengfeng Huang
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Ruihua Wang
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Xinyu Yan
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Yuxin Li
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Yuchao Feng
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Shaozhou Wang
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Xia Yang
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Liutao Chen
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Jun Li
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Leiming You
- School of Basic Medical Sciences, Beijing University of Chinese Medicine, Beijing 100029, People's Republic of China; State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Shangwu Chen
- State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
| | - Guangbin Luo
- School of Basic Medical Sciences, Beijing University of Chinese Medicine, Beijing 100029, People's Republic of China; Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH 44106
| | - Anlong Xu
- School of Basic Medical Sciences, Beijing University of Chinese Medicine, Beijing 100029, People's Republic of China; State Key Laboratory of Biocontrol, Department of Biochemistry, School of Life Sciences, Sun Yat-Sen (Zhongshan) University, Guangzhou, Guangdong 510275, People's Republic of China; and
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28
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Yarosh CA, Iacona JR, Lutz CS, Lynch KW. PSF: nuclear busy-body or nuclear facilitator? WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 6:351-67. [PMID: 25832716 PMCID: PMC4478221 DOI: 10.1002/wrna.1280] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/28/2015] [Accepted: 03/02/2015] [Indexed: 01/25/2023]
Abstract
PTB-associated splicing factor (PSF) is an abundant and essential nucleic acid-binding protein that participates in a wide range of gene regulatory processes and cellular response pathways. At the protein level, PSF consists of multiple domains, many of which remain poorly characterized. Although grouped in a family with the proteins p54nrb/NONO and PSPC1 based on sequence homology, PSF contains additional protein sequence not included in other family members. Consistently, PSF has also been implicated in functions not ascribed to p54nrb/NONO or PSPC1. Here, we provide a review of the cellular activities in which PSF has been implicated and what is known regarding the mechanisms by which PSF functions in each case. We propose that the complex domain arrangement of PSF allows for its diversity of function and integration of activities. Finally, we discuss recent evidence that individual activities of PSF can be regulated independently from one another through the activity of domain-specific co-factors.
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Affiliation(s)
- Christopher A Yarosh
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA
| | - Joseph R Iacona
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers Biomedical and Health Sciences-New Jersey Medical School, Newark, NJ, USA
| | - Carol S Lutz
- Department of Microbiology, Biochemistry and Molecular Genetics, Rutgers Biomedical and Health Sciences-New Jersey Medical School, Newark, NJ, USA
| | - Kristen W Lynch
- Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA, USA
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29
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Machinaga A, Takase-Yoden S. Polyadenylation of Friend murine leukemia virus env-mRNA is affected by its splicing. Microbiol Immunol 2015; 58:474-82. [PMID: 24935657 DOI: 10.1111/1348-0421.12170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/19/2014] [Accepted: 06/10/2014] [Indexed: 01/27/2023]
Abstract
As splicing was previously found to be important for increasing Friend murine leukemia virus env-mRNA stability and translation, we investigated whether splicing of env-mRNA affected the poly(A) tail length using env expression vectors that yielded unspliced or spliced env-mRNA. Incomplete polyadenylation was detected in a fraction of the unspliced env-mRNA products in an env gene-dependent manner, showing that splicing of Friend murine leukemia virus plays an important role in the efficiency of complete polyadenylation of env-mRNA. These results suggested that the promotion of complete polyadenylation of env-mRNA by splicing might partially explain up-regulation of Env protein expression as a result of splicing.
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Affiliation(s)
- Akihito Machinaga
- Department of Bioinformatics, Faculty of Engineering, Soka University, 1-236, Tangi-machi, Hachioji-shi, Tokyo, 192-8577, Japan
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30
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Herdy B, Karonitsch T, Vladimer GI, Tan CSH, Stukalov A, Trefzer C, Bigenzahn JW, Theil T, Holinka J, Kiener HP, Colinge J, Bennett KL, Superti-Furga G. The RNA-binding protein HuR/ELAVL1 regulates IFN-β mRNA abundance and the type I IFN response. Eur J Immunol 2015; 45:1500-11. [PMID: 25678110 DOI: 10.1002/eji.201444979] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 12/18/2014] [Accepted: 02/06/2015] [Indexed: 12/26/2022]
Abstract
Secretion of type I interferon (IFN) is the first cellular reaction to invading pathogens. Despite the protective function of these cytokines, an excessive response to their action can contribute to serious pathologies, such as autoimmune diseases. Transcripts of most cytokines contain adenylate-uridylate (A/U)-rich elements (AREs) that make them highly unstable. RNA-binding proteins (RBPs) are mediators of the regulatory mechanisms that determine the fate of mRNAs containing AREs. Here, we applied an affinity proteomic approach and identified lethal, abnormal vision, drosophila-like 1 (ELAVL1)/Hu antigen R (HuR) as the predominant RBP of the IFN-β mRNA ARE. Reduced expression or chemical inhibition of HuR severely hampered the type I IFN response in various cell lines and fibroblast-like synoviocytes isolated from joints of rheumatoid arthritis patients. These results define a role for HuR as a potent modulator of the type I IFN response. Taken together, HuR could be used as therapeutic target for diseases where type I IFN production is exaggerated.
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Affiliation(s)
- Barbara Herdy
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Thomas Karonitsch
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Division of Rheumatology, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Gregory I Vladimer
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Chris S H Tan
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Alexey Stukalov
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Claudia Trefzer
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Johannes W Bigenzahn
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Tamara Theil
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Johannes Holinka
- Department of Orthopedics, Medical University of Vienna, Vienna, Austria
| | - Hans P Kiener
- Division of Rheumatology, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Jacques Colinge
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Keiryn L Bennett
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Giulio Superti-Furga
- Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
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31
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Shao C, Yang B, Wu T, Huang J, Tang P, Zhou Y, Zhou J, Qiu J, Jiang L, Li H, Chen G, Sun H, Zhang Y, Denise A, Zhang DE, Fu XD. Mechanisms for U2AF to define 3' splice sites and regulate alternative splicing in the human genome. Nat Struct Mol Biol 2014; 21:997-1005. [PMID: 25326705 PMCID: PMC4429597 DOI: 10.1038/nsmb.2906] [Citation(s) in RCA: 132] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 09/25/2014] [Indexed: 12/24/2022]
Abstract
The U2AF heterodimer has been well studied for its role in defining functional 3' splice sites in pre-mRNA splicing, but many fundamental questions still remain unaddressed regarding the function of U2AF in mammalian genomes. Through genome-wide analysis of U2AF-RNA interactions, we report that U2AF has the capacity to directly define ~88% of functional 3' splice sites in the human genome, but numerous U2AF binding events also occur in intronic locations. Mechanistic dissection reveals that upstream intronic binding events interfere with the immediate downstream 3' splice site associated either with the alternative exon, to cause exon skipping, or with the competing constitutive exon, to induce exon inclusion. We further demonstrate partial functional impairment with leukemia-associated mutations in U2AF35, but not U2AF65, in regulated splicing. These findings reveal the genomic function and regulatory mechanism of U2AF in both normal and disease states.
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Affiliation(s)
- Changwei Shao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Bo Yang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Laboratoire de Recherche en Informatique, Institut de Génétique et Microbiologie I, Université Paris-Sud and Centre National de la Recherche Scientifique, Orsay, France
| | - Tongbin Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jie Huang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Peng Tang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yu Zhou
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Jie Zhou
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jinsong Qiu
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Li Jiang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hairi Li
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Geng Chen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hui Sun
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yi Zhang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Alain Denise
- Laboratoire de Recherche en Informatique, Institut de Génétique et Microbiologie I, Université Paris-Sud and Centre National de la Recherche Scientifique, Orsay, France
| | - Dong-Er Zhang
- UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Xiang-Dong Fu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
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32
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Shao C, Yang B, Wu T, Huang J, Tang P, Zhou Y, Zhou J, Qiu J, Jiang L, Li H, Chen G, Sun H, Zhang Y, Denise A, Zhang DE, Fu XD. Mechanisms for U2AF to define 3' splice sites and regulate alternative splicing in the human genome. Nat Struct Mol Biol 2014. [PMID: 25326705 DOI: 10.1038/nsmb2906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The U2AF heterodimer has been well studied for its role in defining functional 3' splice sites in pre-mRNA splicing, but many fundamental questions still remain unaddressed regarding the function of U2AF in mammalian genomes. Through genome-wide analysis of U2AF-RNA interactions, we report that U2AF has the capacity to directly define ~88% of functional 3' splice sites in the human genome, but numerous U2AF binding events also occur in intronic locations. Mechanistic dissection reveals that upstream intronic binding events interfere with the immediate downstream 3' splice site associated either with the alternative exon, to cause exon skipping, or with the competing constitutive exon, to induce exon inclusion. We further demonstrate partial functional impairment with leukemia-associated mutations in U2AF35, but not U2AF65, in regulated splicing. These findings reveal the genomic function and regulatory mechanism of U2AF in both normal and disease states.
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Affiliation(s)
- Changwei Shao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Bo Yang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Laboratoire de Recherche en Informatique, Institut de Génétique et Microbiologie I, Université Paris-Sud and Centre National de la Recherche Scientifique, Orsay, France
| | - Tongbin Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jie Huang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Peng Tang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yu Zhou
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Jie Zhou
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Jinsong Qiu
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Li Jiang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hairi Li
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
| | - Geng Chen
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hui Sun
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yi Zhang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Alain Denise
- Laboratoire de Recherche en Informatique, Institut de Génétique et Microbiologie I, Université Paris-Sud and Centre National de la Recherche Scientifique, Orsay, France
| | - Dong-Er Zhang
- UC San Diego Moores Cancer Center, University of California, San Diego, La Jolla, California, USA
| | - Xiang-Dong Fu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California, USA
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33
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Moreira A. Integrating transcription kinetics with alternative polyadenylation and cell cycle control. Nucleus 2014; 2:556-61. [DOI: 10.4161/nucl.2.6.18064] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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34
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Miura P, Sanfilippo P, Shenker S, Lai EC. Alternative polyadenylation in the nervous system: to what lengths will 3' UTR extensions take us? Bioessays 2014; 36:766-77. [PMID: 24903459 PMCID: PMC4503322 DOI: 10.1002/bies.201300174] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Alternative cleavage and polyadenylation (APA) can diversify coding and non-coding regions, but has particular impact on increasing 3' UTR diversity. Through the gain or loss of regulatory elements such as RNA binding protein and microRNA sites, APA can influence transcript stability, localization, and translational efficiency. Strikingly, the central nervous systems of invertebrate and vertebrate species express a broad range of transcript isoforms bearing extended 3' UTRs. The molecular mechanism that permits proximal 3' end bypass in neurons is mysterious, and only beginning to be elucidated. This landscape of neural 3' UTR extensions, many reaching unprecedented lengths, may help service the unique post-transcriptional regulatory needs of neurons. A combination of approaches, including transcriptome-wide profiling, genetic screening to identify APA factors, biochemical dissection of alternative 3' end formation, and manipulation of individual neural APA targets, will be necessary to gain fuller perspectives on the mechanism and biology of neural-specific 3' UTR lengthening.
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Affiliation(s)
- Pedro Miura
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
| | - Piero Sanfilippo
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
- Louis V. Gerstner, Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center
| | - Sol Shenker
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
- Tri-Institutional Program in Computational Biology and Medicine, Weill Cornell Medical College
| | - Eric C. Lai
- Department of Developmental Biology, Sloan-Kettering Institute, 1275 York Ave, Box 252, New York NY 10065
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35
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Hollerer I, Grund K, Hentze MW, Kulozik AE. mRNA 3'end processing: A tale of the tail reaches the clinic. EMBO Mol Med 2014; 6:16-26. [PMID: 24408965 PMCID: PMC3936486 DOI: 10.1002/emmm.201303300] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Recent advances reveal mRNA 3′end processing as a highly regulated process that fine-tunes posttranscriptional gene expression. This process can affect the site and/or the efficiency of 3′end processing, controlling the quality and the quantity of substrate mRNAs. The regulation of 3′end processing plays a central role in fundamental physiology such as blood coagulation and innate immunity. In addition, errors in mRNA 3′end processing have been associated with a broad spectrum of human diseases, including cancer. We summarize and discuss the paradigmatic shift in the understanding of 3′end processing as a mechanism of posttranscriptional gene regulation that has reached clinical medicine.
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Affiliation(s)
- Ina Hollerer
- Department of Pediatric Oncology, Hematology and Immunology, University of Heidelberg, Heidelberg, Germany
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36
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Laishram RS. Poly(A) polymerase (PAP) diversity in gene expression--star-PAP vs canonical PAP. FEBS Lett 2014; 588:2185-97. [PMID: 24873880 PMCID: PMC6309179 DOI: 10.1016/j.febslet.2014.05.029] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/02/2014] [Accepted: 05/15/2014] [Indexed: 01/09/2023]
Abstract
Almost all eukaryotic mRNAs acquire a poly(A) tail at the 3'-end by a concerted RNA processing event: cleavage and polyadenylation. The canonical PAP, PAPα, was considered the only nuclear PAP involved in general polyadenylation of mRNAs. A phosphoinositide-modulated nuclear PAP, Star-PAP, was then reported to regulate a select set of mRNAs in the cell. In addition, several non-canonical PAPs have been identified with diverse cellular functions. Further, canonical PAP itself exists in multiple isoforms thus illustrating the diversity of PAPs. In this review, we compare two nuclear PAPs, Star-PAP and PAPα with a general overview of PAP diversity in the cell. Emerging evidence suggests distinct niches of target pre-mRNAs for the two PAPs and that modulation of these PAPs regulates distinct cellular functions.
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Affiliation(s)
- Rakesh S Laishram
- Cancer Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
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37
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Pitchiaya S, Heinicke LA, Custer TC, Walter NG. Single molecule fluorescence approaches shed light on intracellular RNAs. Chem Rev 2014; 114:3224-65. [PMID: 24417544 PMCID: PMC3968247 DOI: 10.1021/cr400496q] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Sethuramasundaram Pitchiaya
- Single Molecule Analysis in Real-Time (SMART)
Center, University of Michigan, Ann Arbor, MI 48109-1055, USA
- Single Molecule Analysis Group, Department of
Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Laurie A. Heinicke
- Single Molecule Analysis Group, Department of
Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Thomas C. Custer
- Program in Chemical Biology, University of Michigan,
Ann Arbor, MI 48109-1055, USA
| | - Nils G. Walter
- Single Molecule Analysis in Real-Time (SMART)
Center, University of Michigan, Ann Arbor, MI 48109-1055, USA
- Single Molecule Analysis Group, Department of
Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
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Zheng D, Tian B. RNA-binding proteins in regulation of alternative cleavage and polyadenylation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 825:97-127. [PMID: 25201104 DOI: 10.1007/978-1-4939-1221-6_3] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Almost all eukaryotic pre-mRNAs are processed at the 3' end by the cleavage and polyadenylation (C/P) reaction, which preludes termination of transcription and gives rise to the poly(A) tail of mature mRNA. Genomic studies in recent years have indicated that most eukaryotic mRNA genes have multiple cleavage and polyadenylation sites (pAs), leading to alternative cleavage and polyadenylation (APA) products. APA isoforms generally differ in their 3' untranslated regions (3' UTRs), but can also have different coding sequences (CDSs). APA expands the repertoire of transcripts expressed from the genome, and is highly regulated under various physiological and pathological conditions. Growing lines of evidence have shown that RNA-binding proteins (RBPs) play important roles in regulation of APA. Some RBPs are part of the machinery for C/P; others influence pA choice through binding to adjacent regions. In this chapter, we review cis elements and trans factors involved in C/P, the significance of APA, and increasingly elucidated roles of RBPs in APA regulation. We also discuss analysis of APA using transcriptome-wide techniques as well as molecular biology approaches.
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Affiliation(s)
- Dinghai Zheng
- Department of Biochemistry and Molecular Biology, University of Medicine and Dentistry of New Jersey (UMDNJ)-New Jersey Medical School, 185 South Orange Ave., Newark, NJ, 07103, USA
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New insights into functional roles of the polypyrimidine tract-binding protein. Int J Mol Sci 2013; 14:22906-32. [PMID: 24264039 PMCID: PMC3856098 DOI: 10.3390/ijms141122906] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Revised: 11/13/2013] [Accepted: 11/13/2013] [Indexed: 12/20/2022] Open
Abstract
Polypyrimidine Tract Binding Protein (PTB) is an intensely studied RNA binding protein involved in several post-transcriptional regulatory events of gene expression. Initially described as a pre-mRNA splicing regulator, PTB is now widely accepted as a multifunctional protein shuttling between nucleus and cytoplasm. Accordingly, PTB can interact with selected RNA targets, structural elements and proteins. There is increasing evidence that PTB and its paralog PTBP2 play a major role as repressors of alternatively spliced exons, whose transcription is tissue-regulated. In addition to alternative splicing, PTB is involved in almost all steps of mRNA metabolism, including polyadenylation, mRNA stability and initiation of protein translation. Furthermore, it is well established that PTB recruitment in internal ribosome entry site (IRES) activates the translation of picornaviral and cellular proteins. Detailed studies of the structural properties of PTB have contributed to our understanding of the mechanism of RNA binding by RNA Recognition Motif (RRM) domains. In the present review, we will describe the structural properties of PTB, its paralogs and co-factors, the role in post-transcriptional regulation and actions in cell differentiation and pathogenesis. Defining the multifunctional roles of PTB will contribute to the understanding of key regulatory events in gene expression.
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U1 snRNP-Dependent Suppression of Polyadenylation: Physiological Role and Therapeutic Opportunities in Cancer. Int J Cell Biol 2013; 2013:846510. [PMID: 24285958 PMCID: PMC3826338 DOI: 10.1155/2013/846510] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/05/2013] [Indexed: 11/17/2022] Open
Abstract
Pre-mRNA splicing and polyadenylation are critical steps in the maturation of eukaryotic mRNA. U1 snRNP is an essential component of the splicing machinery and participates in splice-site selection and spliceosome assembly by base-pairing to the 5' splice site. U1 snRNP also plays an additional, nonsplicing global function in 3' end mRNA processing; it actively suppresses the polyadenylation machinery from using early, mostly intronic polyadenylation signals which would lead to aberrant, truncated mRNAs. Thus, U1 snRNP safeguards pre-mRNA transcripts against premature polyadenylation and contributes to the regulation of alternative polyadenylation. Here, we review the role of U1 snRNP in 3' end mRNA processing, outline the evidence that led to the recognition of its physiological, general role in inhibiting polyadenylation, and finally highlight the possibility of manipulating this U1 snRNP function for therapeutic purposes in cancer.
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Elkon R, Ugalde AP, Agami R. Alternative cleavage and polyadenylation: extent, regulation and function. Nat Rev Genet 2013; 14:496-506. [PMID: 23774734 DOI: 10.1038/nrg3482] [Citation(s) in RCA: 583] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The 3' end of most protein-coding genes and long non-coding RNAs is cleaved and polyadenylated. Recent discoveries have revealed that a large proportion of these genes contains more than one polyadenylation site. Therefore, alternative polyadenylation (APA) is a widespread phenomenon, generating mRNAs with alternative 3' ends. APA contributes to the complexity of the transcriptome by generating isoforms that differ either in their coding sequence or in their 3' untranslated regions (UTRs), thereby potentially regulating the function, stability, localization and translation efficiency of target RNAs. Here, we review our current understanding of the polyadenylation process and the latest progress in the identification of APA events, mechanisms that regulate poly(A) site selection, and biological processes and diseases resulting from APA.
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Affiliation(s)
- Ran Elkon
- Division of Gene Regulation, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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Pathologies at the nexus of blood coagulation and inflammation: thrombin in hemostasis, cancer, and beyond. J Mol Med (Berl) 2013; 91:1257-71. [PMID: 23955016 PMCID: PMC3825489 DOI: 10.1007/s00109-013-1074-5] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 07/24/2013] [Accepted: 07/29/2013] [Indexed: 02/06/2023]
Abstract
Thrombin is the protease involved in blood coagulation. Its deregulation can lead to hemostatic abnormalities, which range from subtle subclinical to serious life-threatening coagulopathies, i.e., during septicemia. Additionally, thrombin plays important roles in many (patho)physiological conditions that reach far beyond its well-established role in stemming blood loss and thrombosis, including embryonic development and angiogenesis but also extending to inflammatory processes, complement activation, and even tumor biology. In this review, we will address thrombin's broad roles in diverse (patho)physiological processes in an integrative way. We will also discuss thrombin as an emerging major target for novel therapies.
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Davidovic L, Durand N, Khalfallah O, Tabet R, Barbry P, Mari B, Sacconi S, Moine H, Bardoni B. A novel role for the RNA-binding protein FXR1P in myoblasts cell-cycle progression by modulating p21/Cdkn1a/Cip1/Waf1 mRNA stability. PLoS Genet 2013; 9:e1003367. [PMID: 23555284 PMCID: PMC3605292 DOI: 10.1371/journal.pgen.1003367] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 01/21/2013] [Indexed: 12/14/2022] Open
Abstract
The Fragile X-Related 1 gene (FXR1) is a paralog of the Fragile X Mental Retardation 1 gene (FMR1), whose absence causes the Fragile X syndrome, the most common form of inherited intellectual disability. FXR1P plays an important role in normal muscle development, and its absence causes muscular abnormalities in mice, frog, and zebrafish. Seven alternatively spliced FXR1 transcripts have been identified and two of them are skeletal muscle-specific. A reduction of these isoforms is found in myoblasts from Facio-Scapulo Humeral Dystrophy (FSHD) patients. FXR1P is an RNA–binding protein involved in translational control; however, so far, no mRNA target of FXR1P has been linked to the drastic muscular phenotypes caused by its absence. In this study, gene expression profiling of C2C12 myoblasts reveals that transcripts involved in cell cycle and muscular development pathways are modulated by Fxr1-depletion. We observed an increase of p21—a regulator of cell-cycle progression—in Fxr1-knocked-down mouse C2C12 and FSHD human myoblasts. Rescue of this molecular phenotype is possible by re-expressing human FXR1P in Fxr1-depleted C2C12 cells. FXR1P muscle-specific isoforms bind p21 mRNA via direct interaction with a conserved G-quadruplex located in its 3′ untranslated region. The FXR1P/G-quadruplex complex reduces the half-life of p21 mRNA. In the absence of FXR1P, the upregulation of p21 mRNA determines the elevated level of its protein product that affects cell-cycle progression inducing a premature cell-cycle exit and generating a pool of cells blocked at G0. Our study describes a novel role of FXR1P that has crucial implications for the understanding of its role during myogenesis and muscle development, since we show here that in its absence a reduced number of myoblasts will be available for muscle formation/regeneration, shedding new light into the pathophysiology of FSHD. Muscle development is a complex process controlled by the timely expression of genes encoding crucial regulators of the muscle cell precursors called myoblasts. We know from previous studies that inactivation of the Fragile X related 1 (FXR1) gene in various animal models (mouse, frog, and zebrafish) causes muscular and cardiac abnormalities. Also, FXR1P is reduced in a human myopathy called Fascio-Scapulo Humeral Dystrophy (FSHD), suggesting its critical role in muscle that findings presented in this study contribute to elucidating. Cell-cycle arrest is a prerequisite to differentiation of myoblasts into mature myotubes, which will form the muscle. One key regulator is the p21/Cdkn1a/Cip1/Waf1 protein, which commands myoblasts to stop proliferating, and this action is particularly important during muscle regeneration. In this study, we have identified FXR1P as a novel regulator of p21 expression. We show that FXR1P absence in mouse myoblasts and FSHD-derived myopathic myoblasts increases abnormally the levels of p21, causing a premature cell cycle exit of myoblasts. Our study predicts that FXR1P absence leads to a reduced number of myoblasts available for muscle formation and regeneration. This explains the drastic effects of FXR1 inactivation on muscle and brings a better understanding of the molecular/cellular bases of FSHD.
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Affiliation(s)
- Laetitia Davidovic
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Nelly Durand
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Olfa Khalfallah
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Ricardo Tabet
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS, UMR7104, Inserm U596, Collège de France, Strasbourg University, Illkirch-Graffenstaden, France
| | - Pascal Barbry
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Bernard Mari
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
| | - Sabrina Sacconi
- INSERM U638, Faculté de Médecine, Université de Nice Sophia-Antipolis, Centre de Référence pour les Maladies Neuromusculaires, CHU de Nice, Nice, France
| | - Hervé Moine
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire), CNRS, UMR7104, Inserm U596, Collège de France, Strasbourg University, Illkirch-Graffenstaden, France
| | - Barbara Bardoni
- Institut de Pharmacologie Moléculaire et Cellulaire, CNRS UMR 7275, Valbonne, France
- Université de Nice-Sophia Antipolis, Nice, France
- * E-mail:
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Costessi L, Porro F, Iaconcig A, Nedeljkovic M, Muro AF. Characterization of the distal polyadenylation site of the ß-adducin (Add2) pre-mRNA. PLoS One 2013; 8:e58879. [PMID: 23554949 PMCID: PMC3598803 DOI: 10.1371/journal.pone.0058879] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 02/07/2013] [Indexed: 12/05/2022] Open
Abstract
Most genes have multiple polyadenylation sites (PAS), which are often selected in a tissue-specific manner, altering protein products and affecting mRNA stability, subcellular localization and/or translability. Here we studied the polyadenylation mechanisms associated to the beta-adducin gene (Add2). We have previously shown that the Add2 gene has a very tight regulation of alternative polyadenylation, using proximal PAS in erythroid tissues, and a distal one in brain. Using chimeric minigenes and cell transfections we identified the core elements responsible for polyadenylation at the distal PAS. Deletion of either the hexanucleotide motif (Hm) or the downstream element (DSE) resulted in reduction of mature mRNA levels and activation of cryptic PAS, suggesting an important role for the DSE in polyadenylation of the distal Add2 PAS. Point mutation of the UG repeats present in the DSE, located immediately after the cleavage site, resulted in a reduction of processed mRNA and in the activation of the same cryptic site. RNA-EMSA showed that this region is active in forming RNA-protein complexes. Competition experiments showed that RNA lacking the DSE was not able to compete the RNA-protein complexes, supporting the hypothesis of an essential important role for the DSE. Next, using a RNA-pull down approach we identified some of the proteins bound to the DSE. Among these proteins we found PTB, TDP-43, FBP1 and FBP2, nucleolin, RNA helicase A and vigilin. All these proteins have a role in RNA metabolism, but only PTB has a reported function in polyadenylation. Additional experiments are needed to determine the precise functional role of these proteins in Add2 polyadenylation.
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Affiliation(s)
- Luisa Costessi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Fabiola Porro
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Alessandra Iaconcig
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Mirjana Nedeljkovic
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
| | - Andrés Fernando Muro
- International Centre for Genetic Engineering and Biotechnology (ICGEB), Trieste, Italy
- * E-mail:
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Langemeier J, Radtke M, Bohne J. U1 snRNP-mediated poly(A) site suppression: beneficial and deleterious for mRNA fate. RNA Biol 2013; 10:180-4. [PMID: 23324605 DOI: 10.4161/rna.23314] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The spliceosomal component U1snRNP commits pre-mRNAs to the splicing pathway. Recently, a nuclear RNA surveillance function has been ascribed to U1, namely the suppression of intronic polyadenylation sites. This surveillance holds regulatory potential as it alters the 3' ends of certain receptor tyrosine kinase mRNAs. However, suppression of 3' end processing by U1 snRNP is also the cause of a severe genetic disorder. We described a 3'UTR point mutation creating a 5'SS leading to U1-mediated suppression of 3' end formation. Thus, the inhibitory function of U1 is both beneficial and deleterious where misled. The exact mechanism of how U1 interferes with 3' end processing remains unclear. According to our data, U1 snRNP already interferes with cleavage or poly(A) site selection instead of directly inhibiting poly(A) polymerase as previously assumed. Here, we present alternative models for U1-mediated poly(A) site suppression and discuss the implications for RNA quality control and disease-related mutations.
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Affiliation(s)
- Jörg Langemeier
- Institute for Virology, Hannover Medical School, Hannover, Germany
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Rehfeld A, Plass M, Krogh A, Friis-Hansen L. Alterations in polyadenylation and its implications for endocrine disease. Front Endocrinol (Lausanne) 2013; 4:53. [PMID: 23658553 PMCID: PMC3647115 DOI: 10.3389/fendo.2013.00053] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 04/22/2013] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Polyadenylation is the process in which the pre-mRNA is cleaved at the poly(A) site and a poly(A) tail is added - a process necessary for normal mRNA formation. Genes with multiple poly(A) sites can undergo alternative polyadenylation (APA), producing distinct mRNA isoforms with different 3' untranslated regions (3' UTRs) and in some cases different coding regions. Two thirds of all human genes undergo APA. The efficiency of the polyadenylation process regulates gene expression and APA plays an important part in post-transcriptional regulation, as the 3' UTR contains various cis-elements associated with post-transcriptional regulation, such as target sites for micro-RNAs and RNA-binding proteins. Implications of alterations in polyadenylation for endocrine disease: Alterations in polyadenylation have been found to be causative of neonatal diabetes and IPEX (immune dysfunction, polyendocrinopathy, enteropathy, X-linked) and to be associated with type I and II diabetes, pre-eclampsia, fragile X-associated premature ovarian insufficiency, ectopic Cushing syndrome, and many cancer diseases, including several types of endocrine tumor diseases. PERSPECTIVES Recent developments in high-throughput sequencing have made it possible to characterize polyadenylation genome-wide. Antisense elements inhibiting or enhancing specific poly(A) site usage can induce desired alterations in polyadenylation, and thus hold the promise of new therapeutic approaches. SUMMARY This review gives a detailed description of alterations in polyadenylation in endocrine disease, an overview of the current literature on polyadenylation and summarizes the clinical implications of the current state of research in this field.
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Affiliation(s)
- Anders Rehfeld
- Genomic Medicine, Rigshospitalet, Copenhagen University HospitalCopenhagen, Denmark
| | - Mireya Plass
- Department of Biology, The Bioinformatics Centre, University of CopenhagenCopenhagen, Denmark
| | - Anders Krogh
- Department of Biology, The Bioinformatics Centre, University of CopenhagenCopenhagen, Denmark
| | - Lennart Friis-Hansen
- Genomic Medicine, Rigshospitalet, Copenhagen University HospitalCopenhagen, Denmark
- *Correspondence: Lennart Friis-Hansen, Genomic Medicine, Rigshospitalet, Copenhagen University Hospital, 4113, Blegdamsvej 9, DK2100 Copenhagen, Denmark. e-mail:
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Darmon SK, Lutz CS. Novel upstream and downstream sequence elements contribute to polyadenylation efficiency. RNA Biol 2012; 9:1255-65. [PMID: 23085579 DOI: 10.4161/rna.21957] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Polyadenylation is a 3' mRNA processing event that contributes to gene expression by affecting stability, export and translation of mRNA. Human polyadenylation signals (PAS) have core and auxiliary elements that bind polyadenylation factors upstream and downstream of the cleavage site. The majority of mRNAs do not have optimal upstream and downstream core elements and therefore auxiliary elements can aid in polyadenylation efficiency. Auxiliary elements have previously been identified and studied in a small number of mRNAs. We previously used a global approach to examine auxiliary elements to identify overrepresented motifs by a bioinformatic survey. This predicted information was used to direct our in vivo validation studies, all of which were accomplished using both a tandem in vivo polyadenylation assay and using reporter protein assays measured as luciferase activity. Novel auxiliary elements were placed in a test polyadenylation signal. An in vivo polyadenylation assay was used to determine the strength of the polyadenylation signal. All but one of the novel auxiliary elements enhanced the test polyadenylation signal. Effects of these novel auxiliary elements were also measured by a luciferase assay when placed in the 3' UTR of a firefly luciferase reporter. Two novel downstream auxiliary elements and all of the novel upstream auxiliary elements showed an increase in reporter protein levels. Many well known auxiliary polyadenylation elements have been found to occur in multiple sets. However, in our study, multiple copies of novel auxiliary elements brought reporter protein levels as well as polyadenylation choice back to wild type levels. Structural features of these novel auxiliary elements may also affect the role of auxiliary elements. A MS2 structure placed upstream of the polyadenylation signal can affect polyadenylation in both the positive and negative direction. A large change in RNA structure by using novel complementary auxiliary element also decreased polyadenylation choice and reporter protein levels. Therefore, we conclude that RNA structure has an important role in polyadenylation efficiency.
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Affiliation(s)
- Sarah K Darmon
- Department of Biochemistry and Molecular Biology, UMDNJ-New Jersey Medical School, and the Graduate School of Biomedical Sciences, Newark, NJ, USA
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Langemeier J, Schrom EM, Rabner A, Radtke M, Zychlinski D, Saborowski A, Bohn G, Mandel-Gutfreund Y, Bodem J, Klein C, Bohne J. A complex immunodeficiency is based on U1 snRNP-mediated poly(A) site suppression. EMBO J 2012; 31:4035-44. [PMID: 22968171 DOI: 10.1038/emboj.2012.252] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 08/10/2012] [Indexed: 01/01/2023] Open
Abstract
Biallelic mutations in the untranslated regions (UTRs) of mRNAs are rare causes for monogenetic diseases whose mechanisms remain poorly understood. We investigated a 3'UTR mutation resulting in a complex immunodeficiency syndrome caused by decreased mRNA levels of p14/robld3 by a previously unknown mechanism. Here, we show that the mutation creates a functional 5' splice site (SS) and that its recognition by the spliceosomal component U1 snRNP causes p14 mRNA suppression in the absence of splicing. Histone processing signals are able to rescue p14 expression. Therefore, the mutation interferes only with canonical poly(A)-site 3' end processing. Our data suggest that U1 snRNP inhibits cleavage or poly(A) site recognition. This is the first description of a 3'UTR mutation that creates a functional 5'SS causative of a monogenetic disease. Moreover, our data endorse the recently described role of U1 snRNP in suppression of intronic poly(A) sites, which is here deleterious for p14 mRNA biogenesis.
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Affiliation(s)
- Jörg Langemeier
- Cell and Virus Genetics Group, Institute for Virology, Hannover Medical School, Hannover, Germany
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de Klerk E, Venema A, Anvar SY, Goeman JJ, Hu O, Trollet C, Dickson G, den Dunnen JT, van der Maarel SM, Raz V, 't Hoen PAC. Poly(A) binding protein nuclear 1 levels affect alternative polyadenylation. Nucleic Acids Res 2012; 40:9089-101. [PMID: 22772983 PMCID: PMC3467053 DOI: 10.1093/nar/gks655] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The choice for a polyadenylation site determines the length of the 3′-untranslated region (3′-UTRs) of an mRNA. Inclusion or exclusion of regulatory sequences in the 3′-UTR may ultimately affect gene expression levels. Poly(A) binding protein nuclear 1 (PABPN1) is involved in polyadenylation of pre-mRNAs. An alanine repeat expansion in PABPN1 (exp-PABPN1) causes oculopharyngeal muscular dystrophy (OPMD). We hypothesized that previously observed disturbed gene expression patterns in OPMD muscles may have been the result of an effect of PABPN1 on alternative polyadenylation, influencing mRNA stability, localization and translation. A single molecule polyadenylation site sequencing method was developed to explore polyadenylation site usage on a genome-wide level in mice overexpressing exp-PABPN1. We identified 2012 transcripts with altered polyadenylation site usage. In the far majority, more proximal alternative polyadenylation sites were used, resulting in shorter 3′-UTRs. 3′-UTR shortening was generally associated with increased expression. Similar changes in polyadenylation site usage were observed after knockdown or overexpression of expanded but not wild-type PABPN1 in cultured myogenic cells. Our data indicate that PABPN1 is important for polyadenylation site selection and that reduced availability of functional PABPN1 in OPMD muscles results in use of alternative polyadenylation sites, leading to large-scale deregulation of gene expression.
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Affiliation(s)
- Eleonora de Klerk
- Center for Human and Clinical Genetics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands
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Di Giammartino DC, Nishida K, Manley JL. Mechanisms and consequences of alternative polyadenylation. Mol Cell 2011; 43:853-66. [PMID: 21925375 DOI: 10.1016/j.molcel.2011.08.017] [Citation(s) in RCA: 568] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 08/02/2011] [Accepted: 08/09/2011] [Indexed: 12/11/2022]
Abstract
Alternative polyadenylation (APA) is emerging as a widespread mechanism used to control gene expression. Like alternative splicing, usage of alternative poly(A) sites allows a single gene to encode multiple mRNA transcripts. In some cases, this changes the mRNA coding potential; in other cases, the code remains unchanged but the 3' UTR length is altered, influencing the fate of mRNAs in several ways, for example, by altering the availability of RNA binding protein sites and microRNA binding sites. The mechanisms governing both global and gene-specific APA are only starting to be deciphered. Here we review what is known about these mechanisms and the functional consequences of alternative polyadenylation.
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