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Mars JC, Culjkovic-Kraljacic B, Borden KL. eIF4E orchestrates mRNA processing, RNA export and translation to modify specific protein production. Nucleus 2024; 15:2360196. [PMID: 38880976 PMCID: PMC11185188 DOI: 10.1080/19491034.2024.2360196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 05/22/2024] [Indexed: 06/18/2024] Open
Abstract
The eukaryotic translation initiation factor eIF4E acts as a multifunctional factor that simultaneously influences mRNA processing, export, and translation in many organisms. Its multifactorial effects are derived from its capacity to bind to the methyl-7-guanosine cap on the 5'end of mRNAs and thus can act as a cap chaperone for transcripts in the nucleus and cytoplasm. In this review, we describe the multifactorial roles of eIF4E in major mRNA-processing events including capping, splicing, cleavage and polyadenylation, nuclear export and translation. We discuss the evidence that eIF4E acts at two levels to generate widescale changes to processing, export and ultimately the protein produced. First, eIF4E alters the production of components of the mRNA processing machinery, supporting a widescale reprogramming of multiple mRNA processing events. In this way, eIF4E can modulate mRNA processing without physically interacting with target transcripts. Second, eIF4E also physically interacts with both capped mRNAs and components of the RNA processing or translation machineries. Further, specific mRNAs are sensitive to eIF4E only in particular mRNA processing events. This selectivity is governed by the presence of cis-acting elements within mRNAs known as USER codes that recruit relevant co-factors engaging the appropriate machinery. In all, we describe the molecular bases for eIF4E's multifactorial function and relevant regulatory pathways, discuss the basis for selectivity, present a compendium of ~80 eIF4E-interacting factors which play roles in these activities and provide an overview of the relevance of its functions to its oncogenic potential. Finally, we summarize early-stage clinical studies targeting eIF4E in cancer.
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Affiliation(s)
- Jean-Clément Mars
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
| | - Biljana Culjkovic-Kraljacic
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
| | - Katherine L.B. Borden
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
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Gajjar G, Huggins HP, Kim ES, Huang W, Bonnet FX, Updike DL, Keiper BD. Two germ granule eIF4E isoforms reside in different mRNPs to hand off C elegans mRNAs from translational repression to activation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.24.595216. [PMID: 38826235 PMCID: PMC11142241 DOI: 10.1101/2024.05.24.595216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
We studied the function of translation factor eIF4E isoforms in regulating mRNAs in germ cell granules/condensates. Translational control of mRNAs plays an essential role in germ cell gene regulation. Messenger ribonucleoprotein (mRNP) complexes assemble on mRNAs as they move from the nucleus into perinuclear germ granules to exert both positive and negative post-transcriptional regulation in the cytoplasm. In C. elegans , germ granules are surprisingly dynamic mRNP condensates that remodel during development. Two eIF4E isoforms (called IFE-1 and IFE-3), eIF4E-Interacting Proteins (4EIPs), RBPs, DEAD-box helicases, polyadenylated mRNAs, Argonautes and miRNAs all occupy positions in germ granules. Affinity purification of IFE-1 and IFE-3 allowed mass spectrometry and mRNA-Seq to identify the proteins and mRNAs that populate stable eIF4E mRNPs. We find translationally controlled mRNAs (e.g. pos-1, mex-3, spn-4, etc.) enriched in IFE-3 mRNPs, but excluded from IFE-1 mRNPs. These mRNAs also require IFE-1 for efficient translation. The findings support a model in which oocytes and embryos utilize the two eIF4Es for opposite purposes on critically regulated germline mRNAs. Careful colocalization of the eIF4Es with other germ granule components suggests an architecture in which GLH-1, PGL-1 and the IFEs are stratified to facilitate sequential interactions for mRNAs. Biochemical characterization demonstrates opposing yet cooperative roles for IFE-3 and IFE-1 to hand-off of translationally controlled mRNAs from the repressed to the activated state, respectively. The model involves eIF4E mRNPs shuttling mRNAs through nuclear pore-associated granules/condensates to cytoplasmic ribosomes.
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3
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Zou W, Lv Y, Zhang S, Li L, Sun L, Jiao J. Lysosomal dynamics regulate mammalian cortical neurogenesis. Dev Cell 2024; 59:64-78.e5. [PMID: 38103552 DOI: 10.1016/j.devcel.2023.11.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/16/2023] [Accepted: 11/17/2023] [Indexed: 12/19/2023]
Abstract
Mammalian neocortex formation follows a stereotypical pattern wherein the self-renew and differentiation of neural stem cells are coordinated with diverse organelle dynamics. However, the role of lysosomes in brain development has long been overlooked. Here, we demonstrate the highly dynamic lysosomal quantities, types, and localizations in developing brain. We observed asymmetric endolysosome inheritance during radial glial cell (RGC) division and the increased autolysosomes within intermediate progenitor cells (IPs) and newborn neurons. Disruption of lysosomal function shortens the S phase of the cell cycle and promotes RGC differentiation. Mechanistically, we revealed a post-transcriptional regulation governing ribosome homeostasis and cell-cycle progression through differential lysosomal activity modulation. In the human forebrain organoid, lysosomal dynamics are conserved; specifically, during the mitosis of outer subventricular zone RGCs (oRGs), lysosomes are inherited by the progeny without basal process. Together, our results identify the critical role of lysosomal dynamics in regulating mouse and human brain development.
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Affiliation(s)
- Wenzheng Zou
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Beijing Institute for Stem Cell and Regenerative Medicine, Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Affiliated Hospital of Guangdong Medical University & Key Laboratory of Zebrafish Model for Development and Disease of Guangdong Medical University, Zhanjiang 523710, China
| | - Yuqing Lv
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Beijing Institute for Stem Cell and Regenerative Medicine, Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China
| | - Shukui Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Beijing Institute for Stem Cell and Regenerative Medicine, Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China
| | - Lin Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Beijing Institute for Stem Cell and Regenerative Medicine, Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China
| | - Ling Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; State Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jianwei Jiao
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; Beijing Institute for Stem Cell and Regenerative Medicine, Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China.
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4
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Borden KLB. The eukaryotic translation initiation factor eIF4E unexpectedly acts in splicing thereby coupling mRNA processing with translation: eIF4E induces widescale splicing reprogramming providing system-wide connectivity between splicing, nuclear mRNA export and translation. Bioessays 2024; 46:e2300145. [PMID: 37926700 PMCID: PMC11021180 DOI: 10.1002/bies.202300145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 11/07/2023]
Abstract
Recent findings position the eukaryotic translation initiation factor eIF4E as a novel modulator of mRNA splicing, a process that impacts the form and function of resultant proteins. eIF4E physically interacts with the spliceosome and with some intron-containing transcripts implying a direct role in some splicing events. Moreover, eIF4E drives the production of key components of the splicing machinery underpinning larger scale impacts on splicing. These drive eIF4E-dependent reprogramming of the splicing signature. This work completes a series of studies demonstrating eIF4E acts in all the major mRNA maturation steps whereby eIF4E drives production of the RNA processing machinery and escorts some transcripts through various maturation steps. In this way, eIF4E couples the mRNA processing-export-translation axis linking nuclear mRNA processing to cytoplasmic translation. eIF4E elevation is linked to worse outcomes in acute myeloid leukemia patients where these activities are dysregulated. Understanding these effects provides new insight into post-transcriptional control and eIF4E-driven cancers.
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Affiliation(s)
- Katherine L. B. Borden
- Institute for Research in Immunology and Cancer and Department of Pathology and Cell BiologyUniversity of MontrealMontrealQuebecCanada
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5
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Hernández G, Vazquez-Pianzola P. eIF4E as a molecular wildcard in metazoans RNA metabolism. Biol Rev Camb Philos Soc 2023; 98:2284-2306. [PMID: 37553111 DOI: 10.1111/brv.13005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 07/01/2023] [Accepted: 07/25/2023] [Indexed: 08/10/2023]
Abstract
The evolutionary origin of eukaryotes spurred the transition from prokaryotic-like translation to a more sophisticated, eukaryotic translation. During this process, successive gene duplication of a single, primordial eIF4E gene encoding the mRNA cap-binding protein eukaryotic translation initiation factor 4E (eIF4E) gave rise to a plethora of paralog genes across eukaryotes that underwent further functional diversification in RNA metabolism. The ability to take different roles is due to eIF4E promiscuity in binding many partner proteins, rendering eIF4E a highly versatile and multifunctional player that functions as a molecular wildcard. Thus, in metazoans, eIF4E paralogs are involved in various processes, including messenger RNA (mRNA) processing, export, translation, storage, and decay. Moreover, some paralogs display differential expression in tissues and developmental stages and show variable biochemical properties. In this review, we discuss recent advances shedding light on the functional diversification of eIF4E in metazoans. We emphasise humans and two phylogenetically distant species which have become paradigms for studies on development, namely the fruit fly Drosophila melanogaster and the roundworm Caenorhabditis elegans.
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Affiliation(s)
- Greco Hernández
- mRNA and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (Instituto Nacional de Cancerología, INCan), 22 San Fernando Ave., Tlalpan, Mexico City, 14080, Mexico
| | - Paula Vazquez-Pianzola
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, Berne, 3012, Switzerland
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6
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Assouline S, Gasiorek J, Bergeron J, Lambert C, Culjkovic-Kraljacic B, Cocolakis E, Zakaria C, Szlachtycz D, Yee K, Borden KLB. Molecular targeting of the UDP-glucuronosyltransferase enzymes in high-eukaryotic translation initiation factor 4E refractory/relapsed acute myeloid leukemia patients: a randomized phase II trial of vismodegib, ribavirin with or without decitabine. Haematologica 2023; 108:2946-2958. [PMID: 36951168 PMCID: PMC10620574 DOI: 10.3324/haematol.2023.282791] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/16/2023] [Indexed: 03/24/2023] Open
Abstract
Drug resistance underpins poor outcomes in many malignancies including refractory and relapsed acute myeloid leukemia (R/R AML). Glucuronidation is a common mechanism of drug inactivation impacting many AML therapies, e.g., cytarabine, decitabine, azacytidine and venetoclax. In AML cells, the capacity for glucuronidation arises from increased production of the UDP-glucuronosyltransferase 1A (UGT1A) enzymes. UGT1A elevation was first observed in AML patients who relapsed after response to ribavirin, a drug used to target the eukaryotic translation initiation factor eIF4E, and subsequently in patients who relapsed on cytarabine. UGT1A elevation resulted from increased expression of the sonic-hedgehog transcription factor GLI1. Vismodegib inhibited GLI1, decreased UGT1A levels, reduced glucuronidation of ribavirin and cytarabine, and re-sensitized cells to these drugs. Here, we examined if UGT1A protein levels, and thus glucuronidation activity, were targetable in humans and if this corresponded to clinical response. We conducted a phase II trial using vismodegib with ribavirin, with or without decitabine, in largely heavily pre-treated patients with high-eIF4E AML. Pre-therapy molecular assessment of patients' blasts indicated highly elevated UGT1A levels relative to healthy volunteers. Among patients with partial response, blast response or prolonged stable disease, vismodegib reduced UGT1A levels, which corresponded to effective targeting of eIF4E by ribavirin. In all, our studies are the first to demonstrate that UGT1A protein, and thus glucuronidation, are targetable in humans. These studies pave the way for the development of therapies that impair glucuronidation, one of the most common drug deactivation modalities. Clinicaltrials.gov: NCT02073838.
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Affiliation(s)
- Sarit Assouline
- Jewish General Hospital and McGill University 3755 Cote Ste Catherine, Montreal, Quebec H3T1E2.
| | - Jadwiga Gasiorek
- Institute for Research in Immunology and Cancer and Department of Pathology and Cell Biology, University of Montreal, Montreal, Quebec
| | - Julie Bergeron
- CEMTL installation Maisonneuve Rosemont, 5415 boul. de l'Assomption, Montreal H1T 2M4
| | - Caroline Lambert
- Institute for Research in Immunology and Cancer and Department of Pathology and Cell Biology, University of Montreal, Montreal, Quebec
| | - Biljana Culjkovic-Kraljacic
- Institute for Research in Immunology and Cancer and Department of Pathology and Cell Biology, University of Montreal, Montreal, Quebec
| | - Eftihia Cocolakis
- Jewish General Hospital and McGill University 3755 Cote Ste Catherine, Montreal, Quebec H3T1E2
| | - Chadi Zakaria
- Jewish General Hospital and McGill University 3755 Cote Ste Catherine, Montreal, Quebec H3T1E2
| | - David Szlachtycz
- Jewish General Hospital and McGill University 3755 Cote Ste Catherine, Montreal, Quebec H3T1E2
| | - Karen Yee
- Princess Margaret Cancer Centre, Division of Medical Oncology and Hematology, Toronto, Ontario
| | - Katherine L B Borden
- Institute for Research in Immunology and Cancer and Department of Pathology and Cell Biology, University of Montreal, Montreal, Quebec.
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7
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Rao A, Lyu B, Jahan I, Lubertozzi A, Zhou G, Tedeschi F, Jankowsky E, Kang J, Carstens B, Poss KD, Baskin K, Goldman JA. The translation initiation factor homolog eif4e1c regulates cardiomyocyte metabolism and proliferation during heart regeneration. Development 2023; 150:dev201376. [PMID: 37306388 PMCID: PMC10281269 DOI: 10.1242/dev.201376] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 04/28/2023] [Indexed: 05/25/2023]
Abstract
The eIF4E family of translation initiation factors bind 5' methylated caps and act as the limiting step for mRNA translation. The canonical eIF4E1A is required for cell viability, yet other related eIF4E families exist and are utilized in specific contexts or tissues. Here, we describe a family called Eif4e1c, for which we find roles during heart development and regeneration in zebrafish. The Eif4e1c family is present in all aquatic vertebrates but is lost in all terrestrial species. A core group of amino acids shared over 500 million years of evolution forms an interface along the protein surface, suggesting that Eif4e1c functions in a novel pathway. Deletion of eif4e1c in zebrafish caused growth deficits and impaired survival in juveniles. Mutants surviving to adulthood had fewer cardiomyocytes and reduced proliferative responses to cardiac injury. Ribosome profiling of mutant hearts demonstrated changes in translation efficiency of mRNA for genes known to regulate cardiomyocyte proliferation. Although eif4e1c is broadly expressed, its disruption had most notable impact on the heart and at juvenile stages. Our findings reveal context-dependent requirements for translation initiation regulators during heart regeneration.
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Affiliation(s)
- Anupama Rao
- Department of Biological Chemistry and Pharmacology, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Baken Lyu
- Department of Biological Chemistry and Pharmacology, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Ishrat Jahan
- Department of Biological Chemistry and Pharmacology, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Anna Lubertozzi
- Department of Molecular Genetics, The Ohio State University, Columbus, OH 43210, USA
| | - Gao Zhou
- Center for RNA Molecular Biology, Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106USA
| | - Frank Tedeschi
- Center for RNA Molecular Biology, Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106USA
| | - Eckhard Jankowsky
- Center for RNA Molecular Biology, Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106USA
| | - Junsu Kang
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Bryan Carstens
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Kenneth D. Poss
- Department of Cell Biology, Duke Regeneration Center, Duke University School of Medicine, Durham, NC 27710, USA
| | - Kedryn Baskin
- Department of Cell Biology and Physiology, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Joseph Aaron Goldman
- Department of Biological Chemistry and Pharmacology, The Ohio State University Medical Center, Columbus, OH 43210, USA
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8
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Osma-Garcia IC, Mouysset M, Capitan-Sobrino D, Aubert Y, Turner M, Diaz-Muñoz MD. The RNA binding proteins TIA1 and TIAL1 promote Mcl1 mRNA translation to protect germinal center responses from apoptosis. Cell Mol Immunol 2023; 20:1063-1076. [PMID: 37474714 PMCID: PMC10469172 DOI: 10.1038/s41423-023-01063-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 06/24/2023] [Indexed: 07/22/2023] Open
Abstract
Germinal centers (GCs) are essential for the establishment of long-lasting antibody responses. GC B cells rely on post-transcriptional RNA mechanisms to translate activation-associated transcriptional programs into functional changes in the cell proteome. However, the critical proteins driving these key mechanisms are still unknown. Here, we show that the RNA binding proteins TIA1 and TIAL1 are required for the generation of long-lasting GC responses. TIA1- and TIAL1-deficient GC B cells fail to undergo antigen-mediated positive selection, expansion and differentiation into B-cell clones producing high-affinity antibodies. Mechanistically, TIA1 and TIAL1 control the transcriptional identity of dark- and light-zone GC B cells and enable timely expression of the prosurvival molecule MCL1. Thus, we demonstrate here that TIA1 and TIAL1 are key players in the post-transcriptional program that selects high-affinity antigen-specific GC B cells.
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Affiliation(s)
- Ines C Osma-Garcia
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), Inserm UMR1291, CNRS UMR5051, University Paul Sabatier, CHU Purpan, Toulouse, 31024, France
| | - Mailys Mouysset
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), Inserm UMR1291, CNRS UMR5051, University Paul Sabatier, CHU Purpan, Toulouse, 31024, France
| | - Dunja Capitan-Sobrino
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), Inserm UMR1291, CNRS UMR5051, University Paul Sabatier, CHU Purpan, Toulouse, 31024, France
| | - Yann Aubert
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), Inserm UMR1291, CNRS UMR5051, University Paul Sabatier, CHU Purpan, Toulouse, 31024, France
| | - Martin Turner
- Immunology Program, The Babraham Institute, Cambridge, UK
| | - Manuel D Diaz-Muñoz
- Toulouse Institute for Infectious and Inflammatory Diseases (INFINITy), Inserm UMR1291, CNRS UMR5051, University Paul Sabatier, CHU Purpan, Toulouse, 31024, France.
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9
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Meurant S, Mauclet L, Dieu M, Arnould T, Eyckerman S, Renard P. Endogenous TOM20 Proximity Labeling: A Swiss-Knife for the Study of Mitochondrial Proteins in Human Cells. Int J Mol Sci 2023; 24:ijms24119604. [PMID: 37298552 DOI: 10.3390/ijms24119604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/24/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
Biotin-based proximity labeling approaches, such as BioID, have demonstrated their use for the study of mitochondria proteomes in living cells. The use of genetically engineered BioID cell lines enables the detailed characterization of poorly characterized processes such as mitochondrial co-translational import. In this process, translation is coupled to the translocation of the mitochondrial proteins, alleviating the energy cost typically associated with the post-translational import relying on chaperone systems. However, the mechanisms are still unclear with only few actors identified but none that have been described in mammals yet. We thus profiled the TOM20 proxisome using BioID, assuming that some of the identified proteins could be molecular actors of the co-translational import in human cells. The obtained results showed a high enrichment of RNA binding proteins close to the TOM complex. However, for the few selected candidates, we could not demonstrate a role in the mitochondrial co-translational import process. Nonetheless, we were able to demonstrate additional uses of our BioID cell line. Indeed, the experimental approach used in this study is thus proposed for the identification of mitochondrial co-translational import effectors and for the monitoring of protein entry inside mitochondria with a potential application in the prediction of mitochondrial protein half-life.
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Affiliation(s)
- Sébastien Meurant
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Lorris Mauclet
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Marc Dieu
- Mass Spectrometry Platform (MaSUN), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Thierry Arnould
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
| | - Sven Eyckerman
- VIB-UGent Center for Medical Biotechnology, VIB, 9000 Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
| | - Patricia Renard
- URBC, Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
- Mass Spectrometry Platform (MaSUN), Namur Research Institute for Life Sciences (Narilis), University of Namur (UNamur), 5000 Namur, Belgium
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10
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Xu R, Li X, Huang X, Lin Z, Xiong Y, Chen X, Chu C, Han J, Wang F. Translation-Dependent Skin Hyperplasia Is Promoted by Type 1/17 Inflammation in Psoriasis. J Dermatol Sci 2023; 110:10-18. [PMID: 37024314 DOI: 10.1016/j.jdermsci.2023.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 02/21/2023] [Accepted: 03/29/2023] [Indexed: 04/03/2023]
Abstract
BACKGROUND Psoriasis vulgaris (PV) is a chronic skin inflammatory disease and characterized by aberrant epidermal hyperplasia. The molecule eukaryotic initiation factor (eIF) 4E controls translation initiation of certain protein synthesis and determines cell cycle or differentiation fate. OBJECTIVE To determine the role of eIF4E in keratinocytes abnormal differentiation in the context of psoriasis. METHODS The expression of eIF4E in psoriatic skin lesions and normal skin from human subjects was examined by western blot and immunohistochemistry. In a murine model of psoriasis-like dermatitis that is induced by topical imiquimod, 4EGI-1 was used to inhibit eIF4E activities. To measure murine skin eIF4E and keratinocytes differentiation, immunofluorescence and western blot assays were conducted. Normal human epidermal keratinocytes (NHEK) were isolated, cultured, and stimulated with cytokines including TNF-α, IFN-γ, and IL-17A, respectively. Immunofluorescence and western blot were performed to test eIF4E and effect of 4EGI-1 in a co-culture system. RESULTS Compared with healthy controls, skin lesions from patients with PV exhibited a higher expression of eIF4E, which was positively correlated with the epidermal thickness. This expression pattern of eIF4E was replicated by the imiquimod-induced murine model. Skin hyperplasia and eIF4E activities in the murine model were attenuated by the administration of 4EGI-1. Both IFN-γ and IL-17A, rather than TNF-α, are sufficient to induce NHEK abnormal differentiation. This effect can be disrupted by 4EGI-1. CONCLUSION eIF4E plays a crucial role in keratinocytes abnormal differentiation driven by type 1/17 inflammation in the context of psoriasis. The initiation of abnormal translation provides an alternative treatment target for psoriasis.
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11
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Ghram M, Morris G, Culjkovic-Kraljacic B, Mars JC, Gendron P, Skrabanek L, Revuelta MV, Cerchietti L, Guzman ML, Borden KLB. The eukaryotic translation initiation factor eIF4E reprograms alternative splicing. EMBO J 2023; 42:e110496. [PMID: 36843541 PMCID: PMC10068332 DOI: 10.15252/embj.2021110496] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/28/2023] Open
Abstract
Aberrant splicing is typically attributed to splice-factor (SF) mutation and contributes to malignancies including acute myeloid leukemia (AML). Here, we discovered a mutation-independent means to extensively reprogram alternative splicing (AS). We showed that the dysregulated expression of eukaryotic translation initiation factor eIF4E elevated selective splice-factor production, thereby impacting multiple spliceosome complexes, including factors mutated in AML such as SF3B1 and U2AF1. These changes generated a splicing landscape that predominantly supported altered splice-site selection for ~800 transcripts in cell lines and ~4,600 transcripts in specimens from high-eIF4E AML patients otherwise harboring no known SF mutations. Nuclear RNA immunoprecipitations, export assays, polysome analyses, and mutational studies together revealed that eIF4E primarily increased SF production via its nuclear RNA export activity. By contrast, eIF4E dysregulation did not induce known SF mutations or alter spliceosome number. eIF4E interacted with the spliceosome and some pre-mRNAs, suggesting its direct involvement in specific splicing events. eIF4E induced simultaneous effects on numerous SF proteins, resulting in a much larger range of splicing alterations than in the case of mutation or dysregulation of individual SFs and providing a novel paradigm for splicing control and dysregulation.
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Affiliation(s)
- Mehdi Ghram
- Department of Pathology and Cell Biology, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, Canada.,Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montreal, QC, Canada
| | - Gavin Morris
- Department of Pathology and Cell Biology, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, Canada.,Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montreal, QC, Canada
| | - Biljana Culjkovic-Kraljacic
- Department of Pathology and Cell Biology, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, Canada.,Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montreal, QC, Canada
| | - Jean-Clement Mars
- Department of Pathology and Cell Biology, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, Canada.,Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montreal, QC, Canada
| | - Patrick Gendron
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montreal, QC, Canada
| | - Lucy Skrabanek
- Department of Physiology and Biophysics, Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY, USA.,Applied Bioinformatics Core, Weill Cornell Medicine, New York, NY, USA
| | - Maria Victoria Revuelta
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Leandro Cerchietti
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Monica L Guzman
- Division of Hematology/Oncology, Department of Medicine, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Katherine L B Borden
- Department of Pathology and Cell Biology, Institute for Research in Immunology and Cancer, University of Montreal, Montreal, QC, Canada.,Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Montreal, QC, Canada
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12
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Li J, Liu D, Ren J, Li G, Zhao Z, Zhao H, Yan Q, Duan J, Liu Z. Integrated analysis of RNA methylation regulators crosstalk and immune infiltration for predictive and personalized therapy of diabetic nephropathy. Hum Genomics 2023; 17:6. [PMID: 36765416 PMCID: PMC9912588 DOI: 10.1186/s40246-023-00457-9] [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: 11/28/2022] [Accepted: 02/04/2023] [Indexed: 02/12/2023] Open
Abstract
BACKGROUND RNA methylation is a widely known post-transcriptional regulation which exists in many cancer and immune system diseases. However, the potential role and crosstalk of five types RNA methylation regulators in diabetic nephropathy (DN) and immune microenvironment remain unclear. METHODS The mRNA expression of 37 RNA modification regulators and RNA modification regulators related genes were identified in 112 samples from 5 Gene Expression Omnibus datasets. Nonnegative Matrix Factorization clustering method was performed to determine RNA modification patterns. The ssGSEA algorithms and the expression of human leukocyte antigen were employed to assess the immune microenvironment characteristics. Risk model based on differentially expression genes responsible for the modification regulators was constructed to evaluate its predictive capability in DN patients. Furthermore, the results were validated by using immunofluorescence co-localizations and protein experiments in vitro. RESULTS We found 24 RNA methylation regulators were significant differently expressed in glomeruli in DN group compared with control group. Four methylation-related genes and six RNA regulators were introduced into riskScore model using univariate Logistic regression and integrated LASSO regression, which could precisely distinguish the DN and healthy individuals. Group with high-risk score was associated with high immune infiltration. Three distinct RNA modification patterns were identified, which has significant differences in immune microenvironment, biological pathway and eGFR. Validation analyses showed the METTL3, ADAR1, DNMT1 were upregulated whereas YTHDC1 was downregulated in DN podocyte cell lines comparing with cells cultured by the normal glucose. CONCLUSION Our study reveals that RNA methylation regulators and immune infiltration regulation play critical roles in the pathogenesis of DN. The bioinformatic analyses combine with verification in vitro could provide robust evidence for identification of predictive RNA methylation regulators in DN.
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Affiliation(s)
- Jia Li
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Dongwei Liu
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Jingjing Ren
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Guangpu Li
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Zihao Zhao
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Huanhuan Zhao
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Qianqian Yan
- grid.207374.50000 0001 2189 3846Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,grid.412633.10000 0004 1799 0733Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052 People’s Republic of China ,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052 People’s Republic of China ,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052 People’s Republic of China
| | - Jiayu Duan
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052, People's Republic of China. .,Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, People's Republic of China. .,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052, People's Republic of China. .,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052, People's Republic of China.
| | - Zhangsuo Liu
- Research Institute of Nephrology, Zhengzhou University, Zhengzhou, 450052, People's Republic of China. .,Traditional Chinese Medicine Integrated Department of Nephrology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, People's Republic of China. .,Henan Province Research Center for Kidney Disease, Zhengzhou, 450052, People's Republic of China. .,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, 450052, People's Republic of China.
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13
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Gandin V, English BP, Freeman M, Leroux LP, Preibisch S, Walpita D, Jaramillo M, Singer RH. Cap-dependent translation initiation monitored in living cells. Nat Commun 2022; 13:6558. [PMID: 36323665 PMCID: PMC9630388 DOI: 10.1038/s41467-022-34052-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 10/06/2022] [Indexed: 11/19/2022] Open
Abstract
mRNA translation is tightly regulated to preserve cellular homeostasis. Despite extensive biochemical, genetic, and structural studies, a detailed understanding of mRNA translation regulation is lacking. Imaging methodologies able to resolve the binding dynamics of translation factors at single-cell and single-mRNA resolution were necessary to fully elucidate regulation of this paramount process. Here live-cell spectroscopy and single-particle tracking were combined to interrogate the binding dynamics of endogenous initiation factors to the 5'cap. The diffusion of initiation factors (IFs) changed markedly upon their association with mRNA. Quantifying their diffusion characteristics revealed the sequence of IFs assembly and disassembly in cell lines and the clustering of translation in neurons. This approach revealed translation regulation at high spatial and temporal resolution that can be applied to the formation of any endogenous complex that results in a measurable shift in diffusion.
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Affiliation(s)
- Valentina Gandin
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA
| | - Brian P. English
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA
| | - Melanie Freeman
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA
| | - Louis-Philippe Leroux
- grid.418084.10000 0000 9582 2314Institut National de la Recherche Scientifique (INRS)-Centre Armand-Frappier Santé Biotechnologie (CAFSB), Laval, QC Canada
| | - Stephan Preibisch
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA
| | - Deepika Walpita
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA
| | - Maritza Jaramillo
- grid.418084.10000 0000 9582 2314Institut National de la Recherche Scientifique (INRS)-Centre Armand-Frappier Santé Biotechnologie (CAFSB), Laval, QC Canada
| | - Robert H. Singer
- grid.443970.dJanelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA USA
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14
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Cancer cells hijack RNA processing to rewrite the message. Biochem Soc Trans 2022; 50:1447-1456. [PMID: 36282006 PMCID: PMC9704515 DOI: 10.1042/bst20220621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 10/01/2022] [Accepted: 10/04/2022] [Indexed: 11/17/2022]
Abstract
Typically, cancer is thought to arise due to DNA mutations, dysregulated transcription and/or aberrant signalling. Recently, it has become clear that dysregulated mRNA processing, mRNA export and translation also contribute to malignancy. RNA processing events result in major modifications to the physical nature of mRNAs such as the addition of the methyl-7-guanosine cap, the removal of introns and the addition of polyA tails. mRNA processing is a critical determinant for the protein-coding capacity of mRNAs since these physical changes impact the efficiency by which a given transcript can be exported to the cytoplasm and translated into protein. While many of these mRNA metabolism steps were considered constitutive housekeeping activities, they are now known to be highly regulated with combinatorial and multiplicative impacts i.e. one event will influence the capacity to undergo others. Furthermore, alternative splicing and/or cleavage and polyadenylation can produce transcripts with alternative messages and new functionalities. The coordinated processing of groups of functionally related RNAs can potently re-wire signalling pathways, modulate survival pathways and even re-structure the cell. As postulated by the RNA regulon model, combinatorial regulation of these groups is achieved by the presence of shared cis-acting elements (known as USER codes) which recruit machinery for processing, export or translation. In all, dysregulated RNA metabolism in cancer gives rise to an altered proteome that in turn elicits biological responses related to malignancy. Studies of these events in cancer revealed new mechanisms underpinning malignancies and unearthed novel therapeutic opportunities. In all, cancer cells coopt RNA processing, export and translation to support their oncogenic activity.
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15
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Kang W, Yang Y, Chen C, Yu C. CPSF1 positively regulates NSDHL by alternative polyadenylation and promotes gastric cancer progression. Am J Cancer Res 2022; 12:4566-4583. [PMID: 36381317 PMCID: PMC9641403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023] Open
Abstract
Gastric cancer (GC) is a common malignancies with unfavourable prognosis. As one of the most common RNA modifications in nature, alternative polyadenylation (APA) plays a critical role in the progression of carcinomas. CPSF1 is a critical APA-related factor and is involved in many cancers. Nevertheless, the roles and underlying mechanisms of CPSF1 remain unclear in GC. In this work, we identified that CPSF1 is significantly upregulated in GC and that high CPSF1 expression indicates an unfavourable prognosis in GC patients. Moreover, CPSF1 expression levels were closely associated with tumour size, TNM stage and lymph node metastasis. CPSF1 depletion dramatically weakened GC cell proliferation and metastasis. We then performed RNA sequencing and found numerous downstream genes involved the regulation of CPSF1 with remarkable changes in 3'UTR length, among which NSDHL was positively regulated by CPSF1 and promoted GC progression. In addition, rescue assays demonstrated that NSDHL mediated the carcinogenic effect of CPSF1, and this process potentially involved APA. Therefore, this study showed that CPSF1 promotes GC progression, at least in part, by enhancing NSDHL and offered new insights into therapeutic targets for GC.
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16
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Liu H, Heller-Trulli D, Moore CL. Targeting the mRNA endonuclease CPSF73 inhibits breast cancer cell migration, invasion, and self-renewal. iScience 2022; 25:104804. [PMID: 35992060 PMCID: PMC9385686 DOI: 10.1016/j.isci.2022.104804] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 05/26/2022] [Accepted: 07/15/2022] [Indexed: 12/02/2022] Open
Abstract
Cleavage by the endonuclease CPSF73 and polyadenylation of nascent RNA is an essential step in co-transcriptional mRNA maturation. Recent work has surprisingly identified CPSF73 as a promising drug target for inhibiting the growth of specific cancers, triggering further studies on understanding CPSF73 regulation and functions in cells. Here, we report that a HECT-like E3 ligase, UBE3D, participates in stabilizing CPFS73 protein by preventing its ubiquitin-mediated degradation by the proteasome. Depletion of UBE3D leads to CPSF73 downregulation, a pre-mRNA cleavage defect, and dysregulated gene expression in cells. UBE3D dysfunction or chemical inactivation of CPSF73 inhibited migration and invasion as well as stem cell renewal phenotypes in vitro in triple-negative breast cancer cells. In addition, genetic overexpression of CPSF73 promoted breast cancer stemness and knocking down CPSF73 inhibited stem cell renewal properties. Together, our findings indicate that targeting the pre-mRNA processing nuclease CPSF73 has potential for breast cancer therapy.
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Affiliation(s)
- Huiyun Liu
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Daniel Heller-Trulli
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Claire L. Moore
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA
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17
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Borden K. The search for genetic dark matter and lessons learned from the journey. Biochem Cell Biol 2022; 100:276-281. [DOI: 10.1139/bcb-2022-0138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this review, I describe our scientific journey to unearth the impact of RNA metabolism in cancer using the eukaryotic translation initiation factor eIF4E as an exemplar. This model allowed us to discover new structural, biochemical, and molecular features of RNA processing, and to reveal their substantial impact on cell physiology. This led us to develop proof-of-principle strategies to target these pathways in cancer patients leading to clinical benefit. I discuss the important role that the unexpected plays in research and the necessity of embracing the data even when it clashes with dogma. I also touch on the importance of equity, diversity and inclusion to the success of the scientific enterprise.
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Affiliation(s)
- Katherine Borden
- University of Montreal, 5622, Institute for Research in Immunology and Cancer, Montreal, Quebec, Canada
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18
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Hernández G. The versatile relationships between eIF4E and eIF4E-interacting proteins. Trends Genet 2022; 38:801-804. [PMID: 35568601 DOI: 10.1016/j.tig.2022.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/10/2022] [Accepted: 04/11/2022] [Indexed: 11/18/2022]
Abstract
RNA metabolism and gene expression lie at the core of cellular life. eIF4E has emerged as a central interface in both processes as it plays critical roles in mRNA processing, transport, translation, and storage. Crucially, eIF4E depends on its association with a universe of proteins to form biologically meaningful complexes.
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Affiliation(s)
- Greco Hernández
- Translation and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (Instituto Nacional de Cancerología, INCan). 22 San Fernando Avenue, Tlalpan, 14080-Mexico City, Mexico.
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19
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Teng Z, Hao L, Yang R, Song J, Wang Z, Jiao Y, Fang J, Zheng S, Ma Z, Chen X, Liu S, Cheng Y. Key pituitary miRNAs mediate the expression of pig GHRHR splice variants by regulating splice factors. Int J Biol Macromol 2022; 208:208-218. [PMID: 35306020 DOI: 10.1016/j.ijbiomac.2022.03.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/11/2022] [Accepted: 03/11/2022] [Indexed: 11/28/2022]
Abstract
The growth hormone releasing hormone receptor (GHRHR) is well documented in organism growth and its alternative splicing may generate multiple functional GHRHR splice variants (SVs). Our previous study has demonstrated the key pituitary miRNAs (let-7e and miR-328-5p) in pig regulated the expression of GHRHR SVs by directly targeting to them. And according to recent reports, the interplay between miRNA-based silencing of mRNAs and alternative splicing of pre-mRNAs is a crucial post-transcriptional mechanism. In this study, SF3B3 and CPSF4 were firstly excavated as the splice factors that involved in the formation of GHRHR SVs mediated by let-7e and miR-328-5p through the comparation of the expression relations of GHRHR SVs, let-7e/miR-328-5p and SF3B3/CPSF4 in pituitary tissues between Landrace pigs and BaMa pigs, as well as the prediction of the target relations of let-7e/miR-328-5p with SF3B3 and/or CPSF4. SF3B3 and CPSF4 targeted by let-7e and miR-328-5p were further verified by performing dual-luciferase reporter assays and detecting the expression of target transcripts. Then the RT-PCR, RT-qPCR and Western blot assays were used to confirm SF3B3 and CPSF4 were involved in the formation of the GHRHR SVs, and in this process, let-7e and miR-328-5p mediated GHRHR SVs by regulating SF3B3 and CPSF4. Finally, the target site of SF3B3 on pre-GHRHR was on the Exon 12 to Exon14, while CPSF4 acted on the other fragments of the pre-GHRHR, which were explored by dual-luciferase reporter system preliminarily. To the best of our knowledge, this paper is the first to report the miRNAs regulate GHRHR SVs indirectly by splice factors.
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Affiliation(s)
- Zhaohui Teng
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Linlin Hao
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Rui Yang
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Jie Song
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Zhaoguo Wang
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Yingying Jiao
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Jiayuan Fang
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Shuo Zheng
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Ze Ma
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Xi Chen
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Songcai Liu
- College of Animal Science, Jilin University, Changchun, Jilin 130062, China
| | - Yunyun Cheng
- NHC Key Laboratory of Radiobiology, College of Public Health, Jilin University, Changchun 130021, China.
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20
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Culjkovic-Kraljacic B, Borden KLB. Subcellular Fractionation Suitable for Studies of RNA and Protein Trafficking. Methods Mol Biol 2022; 2502:91-104. [PMID: 35412233 DOI: 10.1007/978-1-0716-2337-4_6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The nuclear pore complex is the major conduit for trafficking between the nucleus and cytoplasm. Nuclear import and export of both proteins and RNAs represent important functional steps for many biological processes. One of the major means to study NPC activity and the nuclear and cytoplasmic distribution of proteins and RNAs is through biochemical fractionation. Here, we describe detailed methods to generate high quality nuclear and cytoplasmic fractions simultaneously capturing RNA and proteins which can be used subsequently for a wide array of biochemical characterizations including proteomics and next generation sequencings.
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Affiliation(s)
- Biljana Culjkovic-Kraljacic
- Department of Pathology and Cell Biology, Institute of Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada.
| | - Katherine L B Borden
- Department of Pathology and Cell Biology, Institute of Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada.
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21
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Mars JC, Ghram M, Culjkovic-Kraljacic B, Borden KLB. The Cap-Binding Complex CBC and the Eukaryotic Translation Factor eIF4E: Co-Conspirators in Cap-Dependent RNA Maturation and Translation. Cancers (Basel) 2021; 13:6185. [PMID: 34944805 PMCID: PMC8699206 DOI: 10.3390/cancers13246185] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 12/26/2022] Open
Abstract
The translation of RNA into protein is a dynamic process which is heavily regulated during normal cell physiology and can be dysregulated in human malignancies. Its dysregulation can impact selected groups of RNAs, modifying protein levels independently of transcription. Integral to their suitability for translation, RNAs undergo a series of maturation steps including the addition of the m7G cap on the 5' end of RNAs, splicing, as well as cleavage and polyadenylation (CPA). Importantly, each of these steps can be coopted to modify the transcript signal. Factors that bind the m7G cap escort these RNAs through different steps of maturation and thus govern the physical nature of the final transcript product presented to the translation machinery. Here, we describe these steps and how the major m7G cap-binding factors in mammalian cells, the cap binding complex (CBC) and the eukaryotic translation initiation factor eIF4E, are positioned to chaperone transcripts through RNA maturation, nuclear export, and translation in a transcript-specific manner. To conceptualize a framework for the flow and integration of this genetic information, we discuss RNA maturation models and how these integrate with translation. Finally, we discuss how these processes can be coopted by cancer cells and means to target these in malignancy.
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Affiliation(s)
- Jean-Clement Mars
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
| | - Mehdi Ghram
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
| | - Biljana Culjkovic-Kraljacic
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
| | - Katherine L B Borden
- Institute for Research in Immunology and Cancer (IRIC), Université de Montréal, Pavillion Marcelle-Coutu, Chemin Polytechnique, Montreal, QC H3T 1J4, Canada
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22
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Kachaev ZM, Ivashchenko SD, Kozlov EN, Lebedeva LA, Shidlovskii YV. Localization and Functional Roles of Components of the Translation Apparatus in the Eukaryotic Cell Nucleus. Cells 2021; 10:3239. [PMID: 34831461 PMCID: PMC8623629 DOI: 10.3390/cells10113239] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 12/15/2022] Open
Abstract
Components of the translation apparatus, including ribosomal proteins, have been found in cell nuclei in various organisms. Components of the translation apparatus are involved in various nuclear processes, particularly those associated with genome integrity control and the nuclear stages of gene expression, such as transcription, mRNA processing, and mRNA export. Components of the translation apparatus control intranuclear trafficking; the nuclear import and export of RNA and proteins; and regulate the activity, stability, and functional recruitment of nuclear proteins. The nuclear translocation of these components is often involved in the cell response to stimulation and stress, in addition to playing critical roles in oncogenesis and viral infection. Many components of the translation apparatus are moonlighting proteins, involved in integral cell stress response and coupling of gene expression subprocesses. Thus, this phenomenon represents a significant interest for both basic and applied molecular biology. Here, we provide an overview of the current data regarding the molecular functions of translation factors and ribosomal proteins in the cell nucleus.
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Affiliation(s)
- Zaur M. Kachaev
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
- Center for Genetics and Life Science, Sirius University of Science and Technology, 354340 Sochi, Russia
| | - Sergey D. Ivashchenko
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
| | - Eugene N. Kozlov
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
| | - Lyubov A. Lebedeva
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
| | - Yulii V. Shidlovskii
- Department of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Z.M.K.); (S.D.I.); (E.N.K.); (L.A.L.)
- Center for Genetics and Life Science, Sirius University of Science and Technology, 354340 Sochi, Russia
- Department of Biology and General Genetics, Sechenov First Moscow State Medical University (Sechenov University), 119992 Moscow, Russia
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Liu H, Moore CL. On the Cutting Edge: Regulation and Therapeutic Potential of the mRNA 3' End Nuclease. Trends Biochem Sci 2021; 46:772-784. [PMID: 33941430 PMCID: PMC8364479 DOI: 10.1016/j.tibs.2021.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 03/18/2021] [Accepted: 04/02/2021] [Indexed: 12/24/2022]
Abstract
Cleavage of nascent transcripts is a fundamental process for eukaryotic mRNA maturation and for the production of different mRNA isoforms. In eukaryotes, cleavage of mRNA precursors by the highly conserved endonuclease CPSF73 is critical for mRNA stability, export from the nucleus, and translation. As an essential enzyme in the cell, CPSF73 surprisingly shows promise as a drug target for specific cancers and for protozoan parasites. In this review, we cover our current understanding of CPSF73 in cleavage and polyadenylation, histone pre-mRNA processing, and transcription termination. We discuss the potential of CPSF73 as a target for novel therapeutics and highlight further research into the regulation of CPSF73 that will be critical to understanding its role in cancer and other diseases.
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Affiliation(s)
- Huiyun Liu
- Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA
| | - Claire L Moore
- Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, Boston, MA 02111, USA.
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Borden K, Culjkovic-Kraljacic B, Cowling VH. To cap it all off, again: dynamic capping and recapping of coding and non-coding RNAs to control transcript fate and biological activity. Cell Cycle 2021; 20:1347-1360. [PMID: 34241559 PMCID: PMC8344758 DOI: 10.1080/15384101.2021.1930929] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The addition of the methyl-7-guanosine (m7G) “cap” on the 5' ends of coding and some non-coding RNAs is essential for their protein coding capacity and biochemical activity, respectively. It was previously considered that capping was a constitutive process that generates a complete cap on all transcripts at steady-state. However, development of new methodologies demonstrated that steady-state capping is a dynamic and regulatable feature of many coding and non-coding RNAs. Indeed, capping status of specific RNAs can flux during differentiation and development, thereby impacting on their protein-coding capacity and activity. Moreover, in some primary cancer specimens, capping can be elevated for transcripts encoding proteins involved in proliferation and survival corresponding to their increased protein levels. Overexpression of one of the capping enzymes (RNMT), the transcription factor MYC or the eukaryotic translation initiation factor eIF4E all led to increased levels of steady-state capping of selected transcripts. Additionally, transcripts can be decapped and recapped, allowing these to be sequestered until needed. This review provides a summary of the major advances in enzymatic and affinity-based approaches to quantify m7G capping. Further, we summarize the evidence for regulation of capping. Capping has emerged as a significant regulatory step in RNA metabolism which is poised to impact a myriad of biological processes.
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Affiliation(s)
- Klb Borden
- Department of Pathology and Cell Biology, Institute of Research in Immunology and Cancer, University of Montreal, Montreal, Canada
| | - B Culjkovic-Kraljacic
- Department of Pathology and Cell Biology, Institute of Research in Immunology and Cancer, University of Montreal, Montreal, Canada
| | - V H Cowling
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, UK, UK
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25
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Delaleau M. Monitoring eIF4E-Dependent Nuclear 3' End mRNA Cleavage. Methods Mol Biol 2021; 2209:347-361. [PMID: 33201480 DOI: 10.1007/978-1-0716-0935-4_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
In eukaryotes, the maturation of the 3' ends of most transcripts involves cleavage and polyadenylation steps in the nucleus. While I was working in the group of Katherine Borden at the University of Montréal, we reported that the eukaryotic translation initiation factor 4E (eIF4E) promotes the 3' end cleavage of specific RNAs. Here, I describe how we monitored this specific maturation pathway using subcellular fractionation, quantitative RT-PCR, and an in vitro cleavage assay with the nuclear fraction.
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Affiliation(s)
- Mildred Delaleau
- Centre de Biophysique Moléculaire (UPR4301), CNRS, Orléans, France.
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26
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The Nuclear Pore Complex and mRNA Export in Cancer. Cancers (Basel) 2020; 13:cancers13010042. [PMID: 33375634 PMCID: PMC7796397 DOI: 10.3390/cancers13010042] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/11/2020] [Accepted: 12/22/2020] [Indexed: 02/07/2023] Open
Abstract
Export of mRNAs from the nucleus to the cytoplasm is a key regulatory step in the expression of proteins. mRNAs are transported through the nuclear pore complex (NPC). Export of mRNAs responds to a variety of cellular stimuli and stresses. Revelations of the specific effects elicited by NPC components and associated co-factors provides a molecular basis for the export of selected RNAs, independent of bulk mRNA export. Aberrant RNA export has been observed in primary human cancer specimens. These cargo RNAs encode factors involved in nearly all facets of malignancy. Indeed, the NPC components involved in RNA export as well as the RNA export machinery can be found to be dysregulated, mutated, or impacted by chromosomal translocations in cancer. The basic mechanisms associated with RNA export with relation to export machinery and relevant NPC components are described. Therapeutic strategies targeting this machinery in clinical trials is also discussed. These findings firmly position RNA export as a targetable feature of cancer along with transcription and translation.
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27
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Culjkovic-Kraljacic B, Skrabanek L, Revuelta MV, Gasiorek J, Cowling VH, Cerchietti L, Borden KLB. The eukaryotic translation initiation factor eIF4E elevates steady-state m 7G capping of coding and noncoding transcripts. Proc Natl Acad Sci U S A 2020; 117:26773-26783. [PMID: 33055213 PMCID: PMC7604501 DOI: 10.1073/pnas.2002360117] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Methyl-7-guanosine (m7G) "capping" of coding and some noncoding RNAs is critical for their maturation and subsequent activity. Here, we discovered that eukaryotic translation initiation factor 4E (eIF4E), itself a cap-binding protein, drives the expression of the capping machinery and increased capping efficiency of ∼100 coding and noncoding RNAs. To quantify this, we developed enzymatic (cap quantification; CapQ) and quantitative cap immunoprecipitation (CapIP) methods. The CapQ method has the further advantage that it captures information about capping status independent of the type of 5' cap, i.e., it is not restricted to informing on m7G caps. These methodological advances led to unanticipated revelations: 1) Many RNA populations are inefficiently capped at steady state (∼30 to 50%), and eIF4E overexpression increased this to ∼60 to 100%, depending on the RNA; 2) eIF4E physically associates with noncoding RNAs in the nucleus; and 3) approximately half of eIF4E-capping targets identified are noncoding RNAs. eIF4E's association with noncoding RNAs strongly positions it to act beyond translation. Coding and noncoding capping targets have activities that influence survival, cell morphology, and cell-to-cell interaction. Given that RNA export and translation machineries typically utilize capped RNA substrates, capping regulation provides means to titrate the protein-coding capacity of the transcriptome and, for noncoding RNAs, to regulate their activities. We also discovered a cap sensitivity element (CapSE) which conferred eIF4E-dependent capping sensitivity. Finally, we observed elevated capping for specific RNAs in high-eIF4E leukemia specimens, supporting a role for cap dysregulation in malignancy. In all, levels of capping RNAs can be regulated by eIF4E.
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Affiliation(s)
- Biljana Culjkovic-Kraljacic
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Lucy Skrabanek
- Applied Bioinformatics Core, Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065
| | - Maria V Revuelta
- Division of Hematology & Medical Oncology, Department of Medicine, Weill Cornell Medicine, New York, NY 10065
| | - Jadwiga Gasiorek
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Victoria H Cowling
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Leandro Cerchietti
- Division of Hematology & Medical Oncology, Department of Medicine, Weill Cornell Medicine, New York, NY 10065
| | - Katherine L B Borden
- Institute of Research in Immunology and Cancer, Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC H3T 1J4, Canada;
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28
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Borden KLB, Volpon L. The diversity, plasticity, and adaptability of cap-dependent translation initiation and the associated machinery. RNA Biol 2020; 17:1239-1251. [PMID: 32496897 PMCID: PMC7549709 DOI: 10.1080/15476286.2020.1766179] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Translation initiation is a critical facet of gene expression with important impacts that underlie cellular responses to stresses and environmental cues. Its dysregulation in many diseases position this process as an important area for the development of new therapeutics. The gateway translation factor eIF4E is typically considered responsible for ‘global’ or ‘canonical’ m7G cap-dependent translation. However, eIF4E impacts translation of specific transcripts rather than the entire translatome. There are many alternative cap-dependent translation mechanisms that also contribute to the translation capacity of the cell. We review the diversity of these, juxtaposing more recently identified mechanisms with eIF4E-dependent modalities. We also explore the multiplicity of functions played by translation factors, both within and outside protein synthesis, and discuss how these differentially contribute to their ultimate physiological impacts. For comparison, we discuss some modalities for cap-independent translation. In all, this review highlights the diverse mechanisms that engage and control translation in eukaryotes.
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Affiliation(s)
- Katherine L B Borden
- Institute of Research in Immunology and Cancer (IRIC), Department of Pathology and Cell Biology, Université de Montréal , Montreal, Québec, Canada
| | - Laurent Volpon
- Institute of Research in Immunology and Cancer (IRIC), Department of Pathology and Cell Biology, Université de Montréal , Montreal, Québec, Canada
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