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Henriques WS, Young JM, Nemudryi A, Nemudraia A, Wiedenheft B, Malik HS. The Diverse Evolutionary Histories of Domesticated Metaviral Capsid Genes in Mammals. Mol Biol Evol 2024; 41:msae061. [PMID: 38507667 PMCID: PMC11011659 DOI: 10.1093/molbev/msae061] [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: 01/25/2024] [Revised: 02/26/2024] [Accepted: 03/04/2024] [Indexed: 03/22/2024] Open
Abstract
Selfish genetic elements comprise significant fractions of mammalian genomes. In rare instances, host genomes domesticate segments of these elements for function. Using a complete human genome assembly and 25 additional vertebrate genomes, we re-analyzed the evolutionary trajectories and functional potential of capsid (CA) genes domesticated from Metaviridae, a lineage of retrovirus-like retrotransposons. Our study expands on previous analyses to unearth several new insights about the evolutionary histories of these ancient genes. We find that at least five independent domestication events occurred from diverse Metaviridae, giving rise to three universally retained single-copy genes evolving under purifying selection and two gene families unique to placental mammals, with multiple members showing evidence of rapid evolution. In the SIRH/RTL family, we find diverse amino-terminal domains, widespread loss of protein-coding capacity in RTL10 despite its retention in several mammalian lineages, and differential utilization of an ancient programmed ribosomal frameshift in RTL3 between the domesticated CA and protease domains. Our analyses also reveal that most members of the PNMA family in mammalian genomes encode a conserved putative amino-terminal RNA-binding domain (RBD) both adjoining and independent from domesticated CA domains. Our analyses lead to a significant correction of previous annotations of the essential CCDC8 gene. We show that this putative RBD is also present in several extant Metaviridae, revealing a novel protein domain configuration in retrotransposons. Collectively, our study reveals the divergent outcomes of multiple domestication events from diverse Metaviridae in the common ancestor of placental mammals.
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Affiliation(s)
- William S Henriques
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717, USA
| | - Janet M Young
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Artem Nemudryi
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717, USA
| | - Anna Nemudraia
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717, USA
| | - Blake Wiedenheft
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT 59717, USA
| | - Harmit S Malik
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
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2
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Shiura H, Kitazawa M, Ishino F, Kaneko-Ishino T. Roles of retrovirus-derived PEG10 and PEG11/RTL1 in mammalian development and evolution and their involvement in human disease. Front Cell Dev Biol 2023; 11:1273638. [PMID: 37842090 PMCID: PMC10570562 DOI: 10.3389/fcell.2023.1273638] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 09/14/2023] [Indexed: 10/17/2023] Open
Abstract
PEG10 and PEG11/RTL1 are paternally expressed, imprinted genes that play essential roles in the current eutherian developmental system and are therefore associated with developmental abnormalities caused by aberrant genomic imprinting. They are also presumed to be retrovirus-derived genes with homology to the sushi-ichi retrotransposon GAG and POL, further expanding our comprehension of mammalian evolution via the domestication (exaptation) of retrovirus-derived acquired genes. In this manuscript, we review the importance of PEG10 and PEG11/RTL1 in genomic imprinting research via their functional roles in development and human disease, including neurodevelopmental disorders of genomic imprinting, Angelman, Kagami-Ogata and Temple syndromes, and the impact of newly inserted DNA on the emergence of newly imprinted regions. We also discuss their possible roles as ancestors of other retrovirus-derived RTL/SIRH genes that likewise play important roles in the current mammalian developmental system, such as in the placenta, brain and innate immune system.
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Affiliation(s)
- Hirosuke Shiura
- Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi, Japan
| | - Moe Kitazawa
- School of BioSciences, Faculty of Science, The University of Melbourne, Melbourne, VIC, Australia
| | - Fumitoshi Ishino
- Institute of Research, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Tomoko Kaneko-Ishino
- Faculty of Nursing, School of Medicine, Tokai University, Isehara, Kanagawa, Japan
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3
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Henriques WS, Young JM, Nemudryi A, Nemudraia A, Wiedenheft B, Malik HS. The diverse evolutionary histories of domesticated metaviral capsid genes in mammals. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.17.558119. [PMID: 37745568 PMCID: PMC10516033 DOI: 10.1101/2023.09.17.558119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Selfish genetic elements and their remnants comprise at least half of the human genome. Active transposons duplicate by inserting copies at new sites in a host genome. Following insertion, transposons can acquire mutations that render them inactive; the accrual of additional mutations can render them unrecognizable over time. However, in rare instances, segments of transposons become useful for the host, in a process called gene domestication. Using the first complete human genome assembly and 25 additional vertebrate genomes, we analyzed the evolutionary trajectories and functional potential of genes domesticated from the capsid genes of Metaviridae, a retroviral-like retrotransposon family. Our analysis reveals four families of domesticated capsid genes in placental mammals with varied evolutionary outcomes, ranging from universal retention to lineage-specific duplications or losses and from purifying selection to lineage-specific rapid evolution. The four families of domesticated capsid genes have divergent amino-terminal domains, inherited from four distinct ancestral metaviruses. Structural predictions reveal that many domesticated genes encode a previously unrecognized RNA-binding domain retained in multiple paralogs in mammalian genomes both adjacent to and independent from the capsid domain. Collectively, our study reveals diverse outcomes of domestication of diverse metaviruses, which led to structurally and evolutionarily diverse genes that encode important, but still largely-unknown functions in placental mammals. (207).
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Affiliation(s)
- William S. Henriques
- Department of Microbiology and Cell Biology, Montana State University, Bozeman MT 59717
| | - Janet M. Young
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109
| | - Artem Nemudryi
- Department of Microbiology and Cell Biology, Montana State University, Bozeman MT 59717
| | - Anna Nemudraia
- Department of Microbiology and Cell Biology, Montana State University, Bozeman MT 59717
| | - Blake Wiedenheft
- Department of Microbiology and Cell Biology, Montana State University, Bozeman MT 59717
| | - Harmit S. Malik
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109
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4
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Gaydukova SA, Moldovan MA, Vallesi A, Heaphy SM, Atkins JF, Gelfand MS, Baranov PV. Nontriplet feature of genetic code in Euplotes ciliates is a result of neutral evolution. Proc Natl Acad Sci U S A 2023; 120:e2221683120. [PMID: 37216548 PMCID: PMC10235951 DOI: 10.1073/pnas.2221683120] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/12/2023] [Indexed: 05/24/2023] Open
Abstract
The triplet nature of the genetic code is considered a universal feature of known organisms. However, frequent stop codons at internal mRNA positions in Euplotes ciliates ultimately specify ribosomal frameshifting by one or two nucleotides depending on the context, thus posing a nontriplet feature of the genetic code of these organisms. Here, we sequenced transcriptomes of eight Euplotes species and assessed evolutionary patterns arising at frameshift sites. We show that frameshift sites are currently accumulating more rapidly by genetic drift than they are removed by weak selection. The time needed to reach the mutational equilibrium is several times longer than the age of Euplotes and is expected to occur after a several-fold increase in the frequency of frameshift sites. This suggests that Euplotes are at an early stage of the spread of frameshifting in expression of their genome. In addition, we find the net fitness burden of frameshift sites to be noncritical for the survival of Euplotes. Our results suggest that fundamental genome-wide changes such as a violation of the triplet character of genetic code can be introduced and maintained solely by neutral evolution.
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Affiliation(s)
- Sofya A. Gaydukova
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow199911, Russia
| | - Mikhail A. Moldovan
- A. A. Kharkevich Institute for Information Transmission Problems RAS, Moscow127051, Russia
| | - Adriana Vallesi
- Laboratory of Eukaryotic Microbiology and Animal Biology, School of Biosciences and Veterinary Medicine, University of Camerino, Camerino62032, Italy
| | - Stephen M. Heaphy
- School of Biochemistry and Cell Biology, University College Cork, CorkT12 XF62, Ireland
| | - John F. Atkins
- School of Biochemistry and Cell Biology, University College Cork, CorkT12 XF62, Ireland
- Department of Human Genetics, University of Utah, Salt Lake City, UT84112
| | - Mikhail S. Gelfand
- A. A. Kharkevich Institute for Information Transmission Problems RAS, Moscow127051, Russia
| | - Pavel V. Baranov
- School of Biochemistry and Cell Biology, University College Cork, CorkT12 XF62, Ireland
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5
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Romero Romero ML, Landerer C, Poehls J, Toth‐Petroczy A. Phenotypic mutations contribute to protein diversity and shape protein evolution. Protein Sci 2022; 31:e4397. [PMID: 36040266 PMCID: PMC9375231 DOI: 10.1002/pro.4397] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/14/2022] [Accepted: 07/04/2022] [Indexed: 11/16/2022]
Abstract
Errors in DNA replication generate genetic mutations, while errors in transcription and translation lead to phenotypic mutations. Phenotypic mutations are orders of magnitude more frequent than genetic ones, yet they are less understood. Here, we review the types of phenotypic mutations, their quantifications, and their role in protein evolution and disease. The diversity generated by phenotypic mutation can facilitate adaptive evolution. Indeed, phenotypic mutations, such as ribosomal frameshift and stop codon readthrough, sometimes serve to regulate protein expression and function. Phenotypic mutations have often been linked to fitness decrease and diseases. Thus, understanding the protein heterogeneity and phenotypic diversity caused by phenotypic mutations will advance our understanding of protein evolution and have implications on human health and diseases.
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Affiliation(s)
- Maria Luisa Romero Romero
- Max Planck Institute of Molecular Cell Biology and Genetics Dresden Germany
- Center for Systems Biology Dresden Dresden Germany
| | - Cedric Landerer
- Max Planck Institute of Molecular Cell Biology and Genetics Dresden Germany
- Center for Systems Biology Dresden Dresden Germany
| | - Jonas Poehls
- Max Planck Institute of Molecular Cell Biology and Genetics Dresden Germany
- Center for Systems Biology Dresden Dresden Germany
| | - Agnes Toth‐Petroczy
- Max Planck Institute of Molecular Cell Biology and Genetics Dresden Germany
- Center for Systems Biology Dresden Dresden Germany
- Cluster of Excellence Physics of Life TU Dresden Dresden Germany
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6
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Abstract
The constrained nature of viral genomes has allowed a translational sleight of hand known as −1 Programmed Ribosomal Frameshifting (−1 PRF) to flourish. Numerous studies have sought to tease apart the mechanisms and implications of −1PRF utilizing a few techniques. The dual-luciferase assay and ribosomal profiling have driven the PRF field to make great advances; however, the use of these assays means that the full impact of the genomic and cellular context on −1 PRF is often lost. Here, we discuss how the Minimal Frameshifting Element (MFE) and its constraints can hide contextual effects on −1 PRF. We review how sequence elements proximal to the traditionally defined MFE, such as the coronavirus attenuator sequence, can affect the observed rates of −1 PRF. Further, the MFE-based approach fully obscured −1 PRF in Barley yellow dwarf virus and would render the exploration of −1 PRF difficult in Porcine reproductive and respiratory syndrome virus, Encephalomyocarditis virus, Theiler’s murine encephalomyelitis virus, and Sindbis virus. Finally, we examine how the cellular context of tRNA abundance, miRNAs, and immune response elements can affect −1 PRF. The use of MFE was instrumental in establishing the basic foundations of PRF; however, it has become clear that the contextual impact on −1 PRF is no longer the exception so much as it is the rule and argues for new approaches to study −1PRF that embrace context. We therefore urge our field to expand the strategies and methods used to explore −1 PRF.
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7
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Champagne J, Pataskar A, Blommaert N, Nagel R, Wernaart D, Ramalho S, Kenski J, Bleijerveld OB, Zaal EA, Berkers CR, Altelaar M, Peeper DS, Faller WJ, Agami R. Oncogene-dependent sloppiness in mRNA translation. Mol Cell 2021; 81:4709-4721.e9. [PMID: 34562372 DOI: 10.1016/j.molcel.2021.09.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 07/13/2021] [Accepted: 08/30/2021] [Indexed: 12/15/2022]
Abstract
mRNA translation is a highly conserved and tightly controlled mechanism for protein synthesis. Despite protein quality control mechanisms, amino acid shortage in melanoma induces aberrant proteins by ribosomal frameshifting. The extent and the underlying mechanisms related to this phenomenon are yet unknown. Here, we show that tryptophan depletion-induced ribosomal frameshifting is a widespread phenomenon in cancer. We termed this event sloppiness and strikingly observed its association with MAPK pathway hyperactivation. Sloppiness is stimulated by RAS activation in primary cells, suppressed by pharmacological inhibition of the oncogenic MAPK pathway in sloppy cells, and restored in cells with acquired resistance to MAPK pathway inhibition. Interestingly, sloppiness causes aberrant peptide presentation at the cell surface, allowing recognition and specific killing of drug-resistant cancer cells by T lymphocytes. Thus, while oncogenes empower cancer progression and aggressiveness, they also expose a vulnerability by provoking the production of aberrant peptides through sloppiness.
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Affiliation(s)
- Julien Champagne
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Abhijeet Pataskar
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Naomi Blommaert
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Remco Nagel
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Demi Wernaart
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Sofia Ramalho
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Juliana Kenski
- Division of Molecular Oncology & Immunology, Oncode Institute, The Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Onno B Bleijerveld
- Proteomics Facility, The Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Esther A Zaal
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands; Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences, Utrecht University and Netherlands Proteomics Centre, Utrecht, the Netherlands
| | - Celia R Berkers
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands; Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences, Utrecht University and Netherlands Proteomics Centre, Utrecht, the Netherlands
| | - Maarten Altelaar
- Proteomics Facility, The Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands; Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research, Utrecht Institute for Pharmaceutical Sciences, Utrecht University and Netherlands Proteomics Centre, Utrecht, the Netherlands
| | - Daniel S Peeper
- Division of Molecular Oncology & Immunology, Oncode Institute, The Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - William J Faller
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands
| | - Reuven Agami
- Division of Oncogenomics, Oncode Institute, the Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, the Netherlands; Erasmus MC, Rotterdam University, Rotterdam, the Netherlands.
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8
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Shiura H, Ono R, Tachibana S, Kohda T, Kaneko-Ishino T, Ishino F. PEG10 viral aspartic protease domain is essential for the maintenance of fetal capillary structure in the mouse placenta. Development 2021; 148:272286. [PMID: 34559199 PMCID: PMC8497776 DOI: 10.1242/dev.199564] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 08/16/2021] [Indexed: 12/13/2022]
Abstract
The therian-specific gene paternally expressed 10 (Peg10) plays an essential role in placenta formation: Peg10 knockout mice exhibit early embryonic lethality as a result of severe placental defects. The PEG10 protein exhibits homology with long terminal repeat (LTR) retrotransposon GAG and POL proteins; therefore, we generated mice harboring a mutation in the highly conserved viral aspartic protease motif in the POL-like region of PEG10 because this motif is essential for the life cycle of LTR retrotransposons/retroviruses. Intriguingly, frequent perinatal lethality, not early embryonic lethality, was observed with fetal and placental growth retardation starting mid-gestation. In the mutant placentas, severe defects were observed in the fetal vasculature, where PEG10 is expressed in the three trophoblast cell layers that surround fetal capillary endothelial cells. Thus, Peg10 has essential roles, not only in early placenta formation, but also in placental vasculature maintenance from mid- to late-gestation. This implies that along the feto-maternal placenta interface an interaction occurs between two retrovirus-derived genes, Peg10 and retrotransposon Gag like 1 (Rtl1, also called Peg11), that is essential for the maintenance of fetal capillary endothelial cells. Summary: Disruption of the highly conserved viral aspartic protease domain in PEG10 causes placental abnormality leading to perinatal lethality in mice.
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Affiliation(s)
- Hirosuke Shiura
- Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi 400-8510, Japan.,Department of Epigenetics, Medical Research Institute (MRI), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Ryuichi Ono
- Division of Cellular and Molecular Toxicology, Center for Biological Safety and Research, National Institute of Health Sciences (NIHS), Kanagawa 210-9501, Japan
| | - Saori Tachibana
- Department of Epigenetics, Medical Research Institute (MRI), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Takashi Kohda
- Faculty of Life and Environmental Sciences, University of Yamanashi, Yamanashi 400-8510, Japan.,Department of Epigenetics, Medical Research Institute (MRI), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
| | - Tomoko Kaneko-Ishino
- Faculty of Nursing, School of Medicine, Tokai University, Kanagawa 259-1193, Japan
| | - Fumitoshi Ishino
- Department of Epigenetics, Medical Research Institute (MRI), Tokyo Medical and Dental University (TMDU), Tokyo 113-8510, Japan
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9
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Segel M, Lash B, Song J, Ladha A, Liu CC, Jin X, Mekhedov SL, Macrae RK, Koonin EV, Zhang F. Mammalian retrovirus-like protein PEG10 packages its own mRNA and can be pseudotyped for mRNA delivery. Science 2021; 373:882-889. [PMID: 34413232 DOI: 10.1126/science.abg6155] [Citation(s) in RCA: 185] [Impact Index Per Article: 61.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 04/26/2021] [Accepted: 07/06/2021] [Indexed: 12/11/2022]
Abstract
Eukaryotic genomes contain domesticated genes from integrating viruses and mobile genetic elements. Among these are homologs of the capsid protein (known as Gag) of long terminal repeat (LTR) retrotransposons and retroviruses. We identified several mammalian Gag homologs that form virus-like particles and one LTR retrotransposon homolog, PEG10, that preferentially binds and facilitates vesicular secretion of its own messenger RNA (mRNA). We showed that the mRNA cargo of PEG10 can be reprogrammed by flanking genes of interest with Peg10's untranslated regions. Taking advantage of this reprogrammability, we developed selective endogenous encapsidation for cellular delivery (SEND) by engineering both mouse and human PEG10 to package, secrete, and deliver specific RNAs. Together, these results demonstrate that SEND is a modular platform suited for development as an efficient therapeutic delivery modality.
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Affiliation(s)
- Michael Segel
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Blake Lash
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jingwei Song
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alim Ladha
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Catherine C Liu
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Xin Jin
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Society of Fellows, Harvard University, Cambridge, MA 02138 USA
| | - Sergei L Mekhedov
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Rhiannon K Macrae
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Feng Zhang
- Howard Hughes Medical Institute, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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10
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Napthine S, Hill CH, Nugent HCM, Brierley I. Modulation of Viral Programmed Ribosomal Frameshifting and Stop Codon Readthrough by the Host Restriction Factor Shiftless. Viruses 2021; 13:v13071230. [PMID: 34202160 PMCID: PMC8310280 DOI: 10.3390/v13071230] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/15/2021] [Accepted: 06/19/2021] [Indexed: 12/18/2022] Open
Abstract
The product of the interferon-stimulated gene C19orf66, Shiftless (SHFL), restricts human immunodeficiency virus replication through downregulation of the efficiency of the viral gag/pol frameshifting signal. In this study, we demonstrate that bacterially expressed, purified SHFL can decrease the efficiency of programmed ribosomal frameshifting in vitro at a variety of sites, including the RNA pseudoknot-dependent signals of the coronaviruses IBV, SARS-CoV and SARS-CoV-2, and the protein-dependent stimulators of the cardioviruses EMCV and TMEV. SHFL also reduced the efficiency of stop-codon readthrough at the murine leukemia virus gag/pol signal. Using size-exclusion chromatography, we confirm the binding of the purified protein to mammalian ribosomes in vitro. Finally, through electrophoretic mobility shift assays and mutational analysis, we show that expressed SHFL has strong RNA binding activity that is necessary for full activity in the inhibition of frameshifting, but shows no clear specificity for stimulatory RNA structures.
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Affiliation(s)
| | | | | | - Ian Brierley
- Correspondence: ; Tel.: +44-12-2333-6914; Fax: +44-12-2333-6926
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11
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Zhang L, Wan Y, Zhang Z, Jiang Y, Gu Z, Ma X, Nie S, Yang J, Lang J, Cheng W, Zhu L. IGF2BP1 overexpression stabilizes PEG10 mRNA in an m6A-dependent manner and promotes endometrial cancer progression. Theranostics 2021; 11:1100-1114. [PMID: 33391523 PMCID: PMC7738899 DOI: 10.7150/thno.49345] [Citation(s) in RCA: 90] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/16/2020] [Indexed: 01/18/2023] Open
Abstract
Rationale: N6-methyladenosine (m6A) mRNA methylation is the most abundant chemical posttranscriptional modification in mRNA and is involved in the regulation of a number of biological processes. Insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) has recently been reported as having the capacity to recognize m6A sites in mRNA and plays a role in regulating mRNA metabolization. However, it is unclear which genes IGF2BP1 targets to identify m6A sites and what are their respective functions in endometrial cancer (EC). Methods: Quantitative PCR, western blot and immunohistochemistry were used to measure IGF2BP1 expression in EC cell lines and tissues. Xenograft experiments were performed to examine the in vivo role of IGF2BP1 in EC cell growth. RNA-binding protein immunoprecipitation sequencing, methylated RNA-binding protein immunoprecipitation sequencing and RNA-sequencing were also conducted to identify potential IGF2BP1 targets involved in EC regulation. Co-immunoprecipitation and mass spectrometry were used to identify IGF2BP1-interacting proteins. Results: IGF2BP1 expression increased in EC, and high expression of this protein correlated with poor prognosis. IGF2BP1 overexpression/knockdown can promote (and inhibit) cell proliferation and regulate the tumor cell cycle and cancer progression, both in vivo and in vitro. Mechanistically, IGF2BP1 can recognize m6A sites in the 3' untranslated region (3'UTR) of Paternally Expressed Gene 10 (PEG10) mRNA and recruits polyadenylate-binding protein 1 (PABPC1) to enhance PEG10 mRNA stability, which consequently promotes PEG10 protein expression. Additionally, it would appear that a large number of PEG10 proteins bind p16 and p18 gene promoter sequences, thereby repressing expression and accelerating the cell cycle. Conclusion: This investigation found that IGF2BP1 has a crucial role in the m6A-dependent regulatory mechanism for endometrial cancer. This study provides new insights into our understanding of disease progression and provides another potential route for understanding biological functions.
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12
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Whiteley AM, Prado MA, de Poot SAH, Paulo JA, Ashton M, Dominguez S, Weber M, Ngu H, Szpyt J, Jedrychowski MP, Easton A, Gygi SP, Kurz T, Monteiro MJ, Brown EJ, Finley D. Global proteomics of Ubqln2-based murine models of ALS. J Biol Chem 2020; 296:100153. [PMID: 33277362 PMCID: PMC7873701 DOI: 10.1074/jbc.ra120.015960] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/21/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022] Open
Abstract
Familial neurodegenerative diseases commonly involve mutations that result in either aberrant proteins or dysfunctional components of the proteolytic machinery that act on aberrant proteins. UBQLN2 is a ubiquitin receptor of the UBL/UBA family that binds the proteasome through its ubiquitin-like domain and is thought to deliver ubiquitinated proteins to proteasomes for degradation. UBQLN2 mutations result in familial amyotrophic lateral sclerosis (ALS)/frontotemporal dementia in humans through an unknown mechanism. Quantitative multiplexed proteomics was used to provide for the first time an unbiased and global analysis of the role of Ubqln2 in controlling the composition of the proteome. We studied several murine models of Ubqln2-linked ALS and also generated Ubqln2 null mutant mice. We identified impacts of Ubqln2 on diverse physiological pathways, most notably serotonergic signaling. Interestingly, we observed an upregulation of proteasome subunits, suggesting a compensatory response to diminished proteasome output. Among the specific proteins whose abundance is linked to UBQLN2 function, the strongest hits were the ubiquitin ligase TRIM32 and two retroelement-derived proteins, PEG10 and CXX1B. Cycloheximide chase studies using induced human neurons and HEK293 cells suggested that PEG10 and TRIM32 are direct clients. Although UBQLN2 directs the degradation of multiple proteins via the proteasome, it surprisingly conferred strong protection from degradation on the Gag-like protein CXX1B, which is expressed from the same family of retroelement genes as PEG10. In summary, this study charts the proteomic landscape of ALS-related Ubqln2 mutants and identifies candidate client proteins that are altered in vivo in disease models and whose degradation is promoted by UBQLN2.
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Affiliation(s)
| | - Miguel A Prado
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | | | - Joao A Paulo
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Marissa Ashton
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Sara Dominguez
- Department of Neuroscience, Genentech Inc, South San Francisco, California, USA
| | - Martin Weber
- Department of Neuroscience, Genentech Inc, South San Francisco, California, USA
| | - Hai Ngu
- Department of Pathology, Genentech Inc, South San Francisco, California, USA
| | - John Szpyt
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Mark P Jedrychowski
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Amy Easton
- Department of Neuroscience, Genentech Inc, South San Francisco, California, USA
| | - Steven P Gygi
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA
| | - Thimo Kurz
- Henry Wellcome Lab of Cell Biology, College of Medical, Veterinary and Life Sciences, Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow, United Kingdom
| | - Mervyn J Monteiro
- Center for Biomedical Engineering and Technology, Department of Anatomy and Neurobiology, University of Maryland Medical School, Baltimore, Maryland, USA
| | - Eric J Brown
- Department of Immunology and Infectious Diseases, Genentech Inc, South San Francisco, California, USA
| | - Daniel Finley
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, USA.
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13
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Mikl M, Pilpel Y, Segal E. High-throughput interrogation of programmed ribosomal frameshifting in human cells. Nat Commun 2020; 11:3061. [PMID: 32546731 PMCID: PMC7297798 DOI: 10.1038/s41467-020-16961-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/28/2020] [Indexed: 12/30/2022] Open
Abstract
Programmed ribosomal frameshifting (PRF) is the controlled slippage of the translating ribosome to an alternative frame. This process is widely employed by human viruses such as HIV and SARS coronavirus and is critical for their replication. Here, we developed a high-throughput approach to assess the frameshifting potential of a sequence. We designed and tested >12,000 sequences based on 15 viral and human PRF events, allowing us to systematically dissect the rules governing ribosomal frameshifting and discover novel regulatory inputs based on amino acid properties and tRNA availability. We assessed the natural variation in HIV gag-pol frameshifting rates by testing >500 clinical isolates and identified subtype-specific differences and associations between viral load in patients and the optimality of PRF rates. We devised computational models that accurately predict frameshifting potential and frameshifting rates, including subtle differences between HIV isolates. This approach can contribute to the development of antiviral agents targeting PRF.
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Affiliation(s)
- Martin Mikl
- Department of Computer Science and Applied Mathematics, Rehovot, 7610001, Israel.
- Department of Molecular Cell Biology and Weizmann Institute of Science, Rehovot, 7610001, Israel.
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 7610001, Israel.
- Department of Human Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa, 31905, Israel.
| | - Yitzhak Pilpel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Eran Segal
- Department of Computer Science and Applied Mathematics, Rehovot, 7610001, Israel.
- Department of Molecular Cell Biology and Weizmann Institute of Science, Rehovot, 7610001, Israel.
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14
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Golda M, Mótyán JA, Mahdi M, Tőzsér J. Functional Study of the Retrotransposon-Derived Human PEG10 Protease. Int J Mol Sci 2020; 21:ijms21072424. [PMID: 32244497 PMCID: PMC7212762 DOI: 10.3390/ijms21072424] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 03/26/2020] [Accepted: 03/30/2020] [Indexed: 12/11/2022] Open
Abstract
Paternally expressed gene 10 (PEG10) is a human retrotransposon-derived imprinted gene. The mRNA of PEG10 encodes two protein isoforms: the Gag-like protein (RF1PEG10) is coded by reading frame 1, while the Gag-Pol-like polyprotein (RF1/RF2PEG10) is coded by reading frames 1 and 2. The proteins are translated by a typical retroviral frameshift mechanism. The protease (PR) domain of RF2PEG10 contains an -Asp-Ser-Gly- sequence, which corresponds to the consensus -Asp-Ser/Thr-Gly- active-site motif of retroviral aspartic proteases. The function of the aspartic protease domain of RF2PEG10 remains unclear. To elucidate the function of PEG10 protease (PRPEG10), we designed a frameshift mutant (fsRF1/RF2PEG10) for comparison with the RF1/RF2PEG10 form. To study the effects of PRPEG10 on cellular proliferation and viability, mammalian HEK293T and HaCaT cells were transfected with plasmids coding for either RF1/RF2PEG10, the frameshift mutant (fsRF1/RF2PEG10), or a PR active-site (D370A) mutant fsRF1/RF2PEG10. Our results indicate that fsRF1/RF2PEG10 overexpression results in increased cellular proliferation. Remarkably, transfection with fsRF1/RF2PEG10 had a detrimental effect on cell viability. We hypothesize that PRPEG10 plays an important role in the function of this retroviral remnant, mediating the proliferation of cells and possibly implicating it in the inhibition of apoptosis.
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Affiliation(s)
- Mária Golda
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (M.G.); (M.M.)
- Doctoral School of Molecular Cell and Immune Biology, University of Debrecen, 4032 Debrecen, Hungary
| | - János András Mótyán
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (M.G.); (M.M.)
- Correspondence: (J.A.M.); (J.T.)
| | - Mohamed Mahdi
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (M.G.); (M.M.)
| | - József Tőzsér
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary; (M.G.); (M.M.)
- Correspondence: (J.A.M.); (J.T.)
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15
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Immunohistochemical detection of the pro-apoptotic Bax∆2 protein in human tissues. Histochem Cell Biol 2020; 154:41-53. [PMID: 32200452 DOI: 10.1007/s00418-020-01874-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2020] [Indexed: 12/11/2022]
Abstract
The pro-apoptotic Bax isoform Bax∆2 was originally discovered in cancer patients with a microsatellite guanine deletion (G8 to G7). This deletion leads to an early stop codon; however, when combined with the alternative splicing of exon 2, the reading frame is restored allowing production of a full-length protein (Bax∆2). Unlike the parental Baxα, Bax∆2 triggers apoptosis through a non-mitochondrial pathway and the expression in human tissues was unknown. Here, we analyzed over 1000 tissue microarray samples from 13 different organs using immunohistochemistry. Bax∆2-positive cells were detected in all examined organs at low rates (1-5%) and mainly scattered throughout the connective tissues. Surprisingly, over 70% of normal colon samples scored high for BaxΔ2-positive staining. Only 7% of malignant colon samples scored high, with most high-grade tumors being negative. A similar pattern was observed in most organs examined. We also showed that both Baxα and Bax∆2 can co-exist in the same cells. Genotyping showed that the majority of Bax∆2-positive normal tissues contain no G7 mutation, but an unexpected high rate of G9 was observed. Although the underlying mechanism remains to be explored, the inverse correlation of Bax∆2 expression with tissue malignancy suggests that it may have a clinical implication in cancer development and treatment.
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16
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Lezzerini M, Penzo M, O'Donohue MF, Marques Dos Santos Vieira C, Saby M, Elfrink HL, Diets IJ, Hesse AM, Couté Y, Gastou M, Nin-Velez A, Nikkels PGJ, Olson AN, Zonneveld-Huijssoon E, Jongmans MCJ, Zhang G, van Weeghel M, Houtkooper RH, Wlodarski MW, Kuiper RP, Bierings MB, van der Werff Ten Bosch J, Leblanc T, Montanaro L, Dinman JD, Da Costa L, Gleizes PE, MacInnes AW. Ribosomal protein gene RPL9 variants can differentially impair ribosome function and cellular metabolism. Nucleic Acids Res 2020; 48:770-787. [PMID: 31799629 PMCID: PMC6954397 DOI: 10.1093/nar/gkz1042] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/17/2019] [Accepted: 11/19/2019] [Indexed: 12/20/2022] Open
Abstract
Variants in ribosomal protein (RP) genes drive Diamond-Blackfan anemia (DBA), a bone marrow failure syndrome that can also predispose individuals to cancer. Inherited and sporadic RP gene variants are also linked to a variety of phenotypes, including malignancy, in individuals with no anemia. Here we report an individual diagnosed with DBA carrying a variant in the 5′UTR of RPL9 (uL6). Additionally, we report two individuals from a family with multiple cancer incidences carrying a RPL9 missense variant. Analysis of cells from these individuals reveals that despite the variants both driving pre-rRNA processing defects and 80S monosome reduction, the downstream effects are remarkably different. Cells carrying the 5′UTR variant stabilize TP53 and impair the growth and differentiation of erythroid cells. In contrast, ribosomes incorporating the missense variant erroneously read through UAG and UGA stop codons of mRNAs. Metabolic profiles of cells carrying the 5′UTR variant reveal an increased metabolism of amino acids and a switch from glycolysis to gluconeogenesis while those of cells carrying the missense variant reveal a depletion of nucleotide pools. These findings indicate that variants in the same RP gene can drive similar ribosome biogenesis defects yet still have markedly different downstream consequences and clinical impacts.
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Affiliation(s)
- Marco Lezzerini
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Marianna Penzo
- Laboratorio di Patologia Clinica, Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale and Centro di Ricerca Biomedica Applicata (CRBA), Policlinico Universitario di S. Orsola, Università di Bologna,Via Massarenti 9, 40138 Bologna, Italy
| | - Marie-Françoise O'Donohue
- LBME, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | | | - Manon Saby
- INSERM UMR S1134, F-75015, Paris, France
| | - Hyung L Elfrink
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.,Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Core Facility Metabolomics, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Illja J Diets
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Anne-Marie Hesse
- University Grenoble Alpes, CEA, INSERM, IRIG, BGE, F-38000 Grenoble, France
| | - Yohann Couté
- University Grenoble Alpes, CEA, INSERM, IRIG, BGE, F-38000 Grenoble, France
| | - Marc Gastou
- Paris University, Paris, France.,Laboratory of Excellence for Red Cell, LABEX GR-Ex, F-75015, Paris, France.,Institute Gustave Roussy, Inserm unit U1170, F-94800 Villejuif, France
| | - Alexandra Nin-Velez
- Department of Comparative Biology and Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA
| | - Peter G J Nikkels
- Department of Pathology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands
| | - Alexandra N Olson
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Evelien Zonneveld-Huijssoon
- Department of Genetics, University Medical Center Utrecht, 3508 AB Utrecht, The Netherlands.,Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marjolijn C J Jongmans
- Department of Genetics, University Medical Center Utrecht, 3508 AB Utrecht, The Netherlands.,Princess Maxima Center for Pediatric Oncology and Utrecht University Children's Hospital, Utrecht, The Netherlands
| | - GuangJun Zhang
- Department of Comparative Biology and Center for Cancer Research, Purdue University, West Lafayette, IN 47907, USA
| | - Michel van Weeghel
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Core Facility Metabolomics, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Riekelt H Houtkooper
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Marcin W Wlodarski
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology and Oncology, Medical Center, Faculty of Medicine, University of Freiburg, D-79106 Freiburg, Germany.,St. Jude's Children Research Hospital, Memphis, TN, USA
| | - Roland P Kuiper
- Department of Genetics, University Medical Center Utrecht, 3508 AB Utrecht, The Netherlands
| | - Marc B Bierings
- Princess Maxima Center for Pediatric Oncology and Utrecht University Children's Hospital, Utrecht, The Netherlands
| | | | - Thierry Leblanc
- Pediatric Hematology/Oncology Service, Robert Debré Hospital, F-75019 Paris, France
| | - Lorenzo Montanaro
- Laboratorio di Patologia Clinica, Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale and Centro di Ricerca Biomedica Applicata (CRBA), Policlinico Universitario di S. Orsola, Università di Bologna,Via Massarenti 9, 40138 Bologna, Italy
| | - Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA
| | - Lydie Da Costa
- INSERM UMR S1134, F-75015, Paris, France.,Paris University, Paris, France.,Laboratory of Excellence for Red Cell, LABEX GR-Ex, F-75015, Paris, France.,Hematology Lab, Robert Debré Hospital, F-75019 Paris, France
| | - Pierre-Emmanuel Gleizes
- LBME, Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Alyson W MacInnes
- Amsterdam UMC, University of Amsterdam, Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology and Metabolism, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
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17
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Napthine S, Bell S, Hill CH, Brierley I, Firth AE. Characterization of the stimulators of protein-directed ribosomal frameshifting in Theiler's murine encephalomyelitis virus. Nucleic Acids Res 2019; 47:8207-8223. [PMID: 31180502 PMCID: PMC6735917 DOI: 10.1093/nar/gkz503] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/24/2019] [Accepted: 05/29/2019] [Indexed: 01/01/2023] Open
Abstract
Many viruses utilize programmed -1 ribosomal frameshifting (-1 PRF) to express additional proteins or to produce frameshift and non-frameshift protein products at a fixed stoichiometric ratio. PRF is also utilized in the expression of a small number of cellular genes. Frameshifting is typically stimulated by signals contained within the mRNA: a 'slippery' sequence and a 3'-adjacent RNA structure. Recently, we showed that -1 PRF in encephalomyocarditis virus (EMCV) is trans-activated by the viral 2A protein, leading to a temporal change in PRF efficiency from 0% to 70% during virus infection. Here we analyzed PRF in the related Theiler's murine encephalomyelitis virus (TMEV). We show that 2A is also required for PRF in TMEV and can stimulate PRF to levels as high as 58% in rabbit reticulocyte cell-free translations and 81% during virus infection. We also show that TMEV 2A trans-activates PRF on the EMCV signal but not vice versa. We present an extensive mutational analysis of the frameshift stimulators (mRNA signals and 2A protein) analysing activity in in vitro translation, electrophoretic mobility shift and in vitro ribosome pausing assays. We also investigate the PRF mRNA signal with RNA structure probing. Our results substantially extend previous characterization of protein-stimulated PRF.
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Affiliation(s)
- Sawsan Napthine
- Division of Virology, Department of Pathology, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Susanne Bell
- Division of Virology, Department of Pathology, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Chris H Hill
- Division of Virology, Department of Pathology, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Ian Brierley
- Division of Virology, Department of Pathology, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
| | - Andrew E Firth
- Division of Virology, Department of Pathology, Addenbrooke's Hospital, University of Cambridge, Cambridge, UK
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18
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Matsumoto S, Caliskan N, Rodnina MV, Murata A, Nakatani K. Small synthetic molecule-stabilized RNA pseudoknot as an activator for -1 ribosomal frameshifting. Nucleic Acids Res 2019; 46:8079-8089. [PMID: 30085309 PMCID: PMC6144811 DOI: 10.1093/nar/gky689] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 07/31/2018] [Indexed: 12/02/2022] Open
Abstract
Programmed –1 ribosomal frameshifting (−1PRF) is a recoding mechanism to make alternative proteins from a single mRNA transcript. −1PRF is stimulated by cis-acting signals in mRNA, a seven-nucleotide slippery sequence and a downstream secondary structure element, which is often a pseudoknot. In this study we engineered the frameshifting pseudoknot from the mouse mammary tumor virus to respond to a rationally designed small molecule naphthyridine carbamate tetramer (NCTn). We demonstrate that NCTn can stabilize the pseudoknot structure in mRNA and activate –1PRF both in vitro and in human cells. The results illustrate how NCTn-inducible –1PRF may serve as an important component of the synthetic biology toolbox for the precise control of gene expression using small synthetic molecules.
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Affiliation(s)
- Saki Matsumoto
- Department of Regulatory Bioorganic Chemistry, The Institute of Scientific and Industrial Research (ISIR), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - Neva Caliskan
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research, Josef-Schneider-Str.2/D15, 97080, Würzburg, Germany
| | - Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
| | - Asako Murata
- Department of Regulatory Bioorganic Chemistry, The Institute of Scientific and Industrial Research (ISIR), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
| | - Kazuhiko Nakatani
- Department of Regulatory Bioorganic Chemistry, The Institute of Scientific and Industrial Research (ISIR), Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan
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19
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Yahiro Y, Maeda S, Shinohara N, Jokoji G, Sakuma D, Setoguchi T, Ishidou Y, Nagano S, Komiya S, Taniguchi N. PEG10 counteracts signaling pathways of TGF-β and BMP to regulate growth, motility and invasion of SW1353 chondrosarcoma cells. J Bone Miner Metab 2019; 37:441-454. [PMID: 30094509 DOI: 10.1007/s00774-018-0946-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 07/25/2018] [Indexed: 01/07/2023]
Abstract
Recently, we reported highly active transforming growth factor (TGF)-β and bone morphogenetic protein (BMP) signaling in human chondrosarcoma samples and concurrent downregulation of paternally expressed gene 10 (PEG10). PEG10 expression was suppressed by TGF-β signaling, and PEG10 interfered with the TGF-β and BMP-SMAD pathways in chondrosarcoma cells. However, the roles of PEG10 in bone tumors, including chondrosarcoma, remain unknown. Here, we report that PEG10 promotes SW1353 chondrosarcoma cell growth by preventing TGF-β1-mediated suppression. In contrast, PEG10 knockdown augments the TGF-β1-induced motility of SW1353 cells. Individually, TGF-β1 and PEG10 siRNA increase AKT phosphorylation, whereas an AKT inhibitor, MK2206, mitigates the effect of PEG10 silencing on cell migration. SW1353 cell invasion was enhanced by BMP-6, which was further increased by PEG10 silencing. The effect of siPEG10 was suppressed by inhibitors of matrix metalloproteinase (MMP). BMP-6 induced expression of MMP-1, -3, and -13, and PEG10 lentivirus or PEG10 siRNA downregulated or further upregulated these MMPs, respectively. PEG10 siRNA increased BMP-6-induced phosphorylation of p38 MAPK and AKT, whereas the p38 inhibitor SB203580 and MK2206 diminished SW1353 cell invasion by PEG10 siRNA. SB203580 and MK2206 impeded the enhancing effect of PEG10 siRNA on the BMP-6-induced expression of MMP-1, -3, and -13. Our findings suggest dual functions for PEG10: accelerating cell growth by suppressing TGF-β signaling and inhibiting cell motility and invasion by interfering with TGF-β and BMP signaling via the AKT and p38 pathways, respectively. Thus, PEG10 might be a molecular target for suppressing the aggressive phenotypes of chondrosarcoma cells.
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Affiliation(s)
- Yuhei Yahiro
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Shingo Maeda
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan.
| | - Naohiro Shinohara
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Go Jokoji
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Daisuke Sakuma
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Takao Setoguchi
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Yasuhiro Ishidou
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Satoshi Nagano
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Setsuro Komiya
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
| | - Noboru Taniguchi
- Department of Medical Joint Materials, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
- Department of Orthopaedic Surgery, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, Kagoshima, 890-8544, Japan
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20
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Czech A, Konarev PV, Goebel I, Svergun DI, Wills PR, Ignatova Z. Octa-repeat domain of the mammalian prion protein mRNA forms stable A-helical hairpin structure rather than G-quadruplexes. Sci Rep 2019; 9:2465. [PMID: 30792490 PMCID: PMC6384910 DOI: 10.1038/s41598-019-39213-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 12/19/2018] [Indexed: 12/22/2022] Open
Abstract
Misfolding and aggregation of prion protein (PrP) causes neurodegenerative diseases like Creutzfeldt-Jakob disease (CJD) and scrapie. Besides the consensus that spontaneous conversion of normal cellular PrPC into misfolded and aggregating PrPSc is the central event in prion disease, an alternative hypothesis suggests the generation of pathological PrPSc by rare translational frameshifting events in the octa-repeat domain of the PrP mRNA. Ribosomal frameshifting most commonly relies on a slippery site and an adjacent stable RNA structure to stall translating ribosome. Hence, it is crucial to unravel the secondary structure of the octa-repeat domain of PrP mRNA. Each of the five octa-repeats contains a motif (GGCGGUGGUGGCUGGG) which alone in vitro forms a G-quadruplex. Since the propensity of mRNA to form secondary structure depends on the sequence context, we set to determine the structure of the complete octa-repeat region. We assessed the structure of full-length octa-repeat domain of PrP mRNA using dynamic light scattering (DLS), small angle X-ray scattering (SAXS), circular dichroism (CD) spectroscopy and selective 2'-hydroxyl acylation analysis by primer extension (SHAPE). Our data show that the PrP octa-repeat mRNA forms stable A-helical hairpins with no evidence of G-quadruplex structure even in the presence of G-quadruplex stabilizing agents.
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Affiliation(s)
- Andreas Czech
- Institute of Biochemistry and Molecular Biology University of Hamburg, Hamburg, Germany.
| | - Petr V Konarev
- A. V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Moscow, Russia
- National Research Centre "Kurchatov Institute", Moscow, Russia
| | - Ingrid Goebel
- Institute of Biochemistry and Molecular Biology University of Hamburg, Hamburg, Germany
| | - Dmitri I Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, c/o DESY, Hamburg, Germany
| | - Peter R Wills
- Department of Physics, University of Auckland, Auckland, New Zealand
| | - Zoya Ignatova
- Institute of Biochemistry and Molecular Biology University of Hamburg, Hamburg, Germany
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21
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Xie T, Pan S, Zheng H, Luo Z, Tembo KM, Jamal M, Yu Z, Yu Y, Xia J, Yin Q, Wang M, Yuan W, Zhang Q, Xiong J. PEG10 as an oncogene: expression regulatory mechanisms and role in tumor progression. Cancer Cell Int 2018; 18:112. [PMID: 30123090 PMCID: PMC6090666 DOI: 10.1186/s12935-018-0610-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Accepted: 08/04/2018] [Indexed: 02/07/2023] Open
Abstract
Cancer is a major public health problem as one of the leading causes of death worldwide. Deciphering the molecular regulation mechanisms of tumor progression can make way for tumor diagnosis and therapy. Paternally expressed gene 10 (PEG10), located on human chromosome 7q21.3, has turned out to be an oncogene implicated in the proliferation, apoptosis and metastasis of tumors. PEG10 has been found to be positively expressed in a variety of cancers with seemingly complex expression regulation mechanisms. In this review, we focus on the most vital factors influencing PEG10 expression and recapitulate some of the currently known and potential mechanisms of PEG10 affecting tumor progression, as understanding the molecular regulatory mechanisms of tumor progression can provide potential PEG10 related diagnosis and biomarker specific targeted therapies.
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Affiliation(s)
- Tian Xie
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Shan Pan
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Hang Zheng
- 2Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, 430071 China
| | - Zilv Luo
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | | | - Muhammad Jamal
- 4State Key Laboratory of Agriculture Microbiology, Huazhong Agricultural University, Wuhan, 430070 China
| | - Zhongyang Yu
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Yao Yu
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Jing Xia
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Qian Yin
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Meng Wang
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Wen Yuan
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
| | - Qiuping Zhang
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China.,5Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University, Wuhan, 430071 China
| | - Jie Xiong
- 1Department of Immunology, School of Basic Medical Science, Wuhan University, Wuhan, 430071 China
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22
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Laumont CM, Perreault C. Exploiting non-canonical translation to identify new targets for T cell-based cancer immunotherapy. Cell Mol Life Sci 2018; 75:607-621. [PMID: 28823056 PMCID: PMC11105255 DOI: 10.1007/s00018-017-2628-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 08/03/2017] [Accepted: 08/16/2017] [Indexed: 01/11/2023]
Abstract
Cryptic MHC I-associated peptides (MAPs) are produced via two mechanisms: translation of protein-coding genes in non-canonical reading frames and translation of allegedly non-coding sequences. In general, cryptic MAPs are coded by relatively short open reading frames whose translation can be regulated at the level of initiation, elongation or termination. In contrast to conventional MAPs, the processing of cryptic MAPs is frequently proteasome independent. The existence of cryptic MAPs derived from allegedly non-coding regions enlarges the scope of CD8 T cell immunosurveillance from a mere ~2% to as much as ~75% of the human genome. Considering that 99% of cancer-specific mutations are located in those allegedly non-coding regions, cryptic MAPs could furthermore represent a particularly rich source of tumor-specific antigens. However, extensive proteogenomic analyses will be required to determine the breath as well as the temporal and spatial plasticity of the cryptic MAP repertoire in normal and neoplastic cells.
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Affiliation(s)
- Céline M Laumont
- Institute for Research in Immunology and Cancer, Université de Montréal, Station Centre-Ville, PO Box 6128, Montreal, QC, H3C 3J7, Canada
- Department of Medicine, Faculty of Medicine, Université de Montréal, Station Centre-Ville, PO Box 6128, Montreal, QC, H3C 3J7, Canada
| | - Claude Perreault
- Institute for Research in Immunology and Cancer, Université de Montréal, Station Centre-Ville, PO Box 6128, Montreal, QC, H3C 3J7, Canada.
- Department of Medicine, Faculty of Medicine, Université de Montréal, Station Centre-Ville, PO Box 6128, Montreal, QC, H3C 3J7, Canada.
- Division of Hematology, Hôpital Maisonneuve-Rosemont, 5415 de l'Assomption Boulevard, Montreal, QC, H1T 2M4, Canada.
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23
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TGF-β signalling and PEG10 are mutually exclusive and inhibitory in chondrosarcoma cells. Sci Rep 2017; 7:13494. [PMID: 29044189 PMCID: PMC5647403 DOI: 10.1038/s41598-017-13994-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 10/04/2017] [Indexed: 11/24/2022] Open
Abstract
Histological distinction between enchondroma and chondrosarcoma is difficult because of a lack of definitive biomarkers. Here, we found highly active transforming growth factor-β (TGF-β) and bone morphogenetic protein (BMP) signalling in human chondrosarcomas compared with enchondromas by immunohistochemistry of phosphorylated SMAD3 and SMAD1/5. In contrast, the chondrogenic master regulator SOX9 was dramatically down-regulated in grade 1 chondrosarcoma. Paternally expressed gene 10 (PEG10) was identified by microarray analysis as a gene overexpressed in chondrosarcoma SW1353 and Hs 819.T cells compared with C28/I2 normal chondrocytes, while TGF-β1 treatment, mimicking higher grade tumour conditions, suppressed PEG10 expression. Enchondroma samples exhibited stronger expression of PEG10 compared with chondrosarcomas, suggesting a negative association of PEG10 with malignant cartilage tumours. In chondrosarcoma cell lines, application of the TGF-β signalling inhibitor, SB431542, increased the protein level of PEG10. Reporter assays revealed that PEG10 repressed TGF-β and BMP signalling, which are both SMAD pathways, whereas PEG10 knockdown increased the level of phosphorylated SMAD3 and SMAD1/5/9. Our results indicate that mutually exclusive expression of PEG10 and phosphorylated SMADs in combination with differentially expressed SOX9 is an index to distinguish between enchondroma and chondrosarcoma, while PEG10 and TGF-β signalling are mutually inhibitory in chondrosarcoma cells.
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Dinan AM, Atkins JF, Firth AE. ASXL gain-of-function truncation mutants: defective and dysregulated forms of a natural ribosomal frameshifting product? Biol Direct 2017; 12:24. [PMID: 29037253 PMCID: PMC5644247 DOI: 10.1186/s13062-017-0195-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 10/04/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Programmed ribosomal frameshifting (PRF) is a gene expression mechanism which enables the translation of two N-terminally coincident, C-terminally distinct protein products from a single mRNA. Many viruses utilize PRF to control or regulate gene expression, but very few phylogenetically conserved examples are known in vertebrate genes. Additional sex combs-like (ASXL) genes 1 and 2 encode important epigenetic and transcriptional regulatory proteins that control the expression of homeotic genes during key developmental stages. Here we describe an ~150-codon overlapping ORF (termed TF) in ASXL1 and ASXL2 that, with few exceptions, is conserved throughout vertebrates. RESULTS Conservation of the TF ORF, strong suppression of synonymous site variation in the overlap region, and the completely conserved presence of an EH[N/S]Y motif (a known binding site for Host Cell Factor-1, HCF-1, an epigenetic regulatory factor), all indicate that TF is a protein-coding sequence. A highly conserved UCC_UUU_CGU sequence (identical to the known site of +1 ribosomal frameshifting for influenza virus PA-X expression) occurs at the 5' end of the region of enhanced synonymous site conservation in ASXL1. Similarly, a highly conserved RG_GUC_UCU sequence (identical to a known site of -2 ribosomal frameshifting for arterivirus nsp2TF expression) occurs at the 5' end of the region of enhanced synonymous site conservation in ASXL2. CONCLUSIONS Due to a lack of appropriate splice forms, or initiation sites, the most plausible mechanism for translation of the ASXL1 and 2 TF regions is ribosomal frameshifting, resulting in a transframe fusion of the N-terminal half of ASXL1 or 2 to the TF product, termed ASXL-TF. Truncation or frameshift mutants of ASXL are linked to myeloid malignancies and genetic diseases, such as Bohring-Opitz syndrome, likely at least in part as a result of gain-of-function or dominant-negative effects. Our hypothesis now indicates that these disease-associated mutant forms represent overexpressed defective versions of ASXL-TF. REVIEWERS This article was reviewed by Laurence Hurst and Eugene Koonin.
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Affiliation(s)
- Adam M Dinan
- Department of Pathology, Division of Virology, University of Cambridge, Cambridge, CB2 1QP, UK
| | - John F Atkins
- School of Biochemistry and Cell Biology, University College Cork, T12 YT57, Cork, Ireland.,Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Andrew E Firth
- Department of Pathology, Division of Virology, University of Cambridge, Cambridge, CB2 1QP, UK.
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25
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Atkins JF, Loughran G, Bhatt PR, Firth AE, Baranov PV. Ribosomal frameshifting and transcriptional slippage: From genetic steganography and cryptography to adventitious use. Nucleic Acids Res 2016; 44:7007-78. [PMID: 27436286 PMCID: PMC5009743 DOI: 10.1093/nar/gkw530] [Citation(s) in RCA: 161] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 05/26/2016] [Indexed: 12/15/2022] Open
Abstract
Genetic decoding is not ‘frozen’ as was earlier thought, but dynamic. One facet of this is frameshifting that often results in synthesis of a C-terminal region encoded by a new frame. Ribosomal frameshifting is utilized for the synthesis of additional products, for regulatory purposes and for translational ‘correction’ of problem or ‘savior’ indels. Utilization for synthesis of additional products occurs prominently in the decoding of mobile chromosomal element and viral genomes. One class of regulatory frameshifting of stable chromosomal genes governs cellular polyamine levels from yeasts to humans. In many cases of productively utilized frameshifting, the proportion of ribosomes that frameshift at a shift-prone site is enhanced by specific nascent peptide or mRNA context features. Such mRNA signals, which can be 5′ or 3′ of the shift site or both, can act by pairing with ribosomal RNA or as stem loops or pseudoknots even with one component being 4 kb 3′ from the shift site. Transcriptional realignment at slippage-prone sequences also generates productively utilized products encoded trans-frame with respect to the genomic sequence. This too can be enhanced by nucleic acid structure. Together with dynamic codon redefinition, frameshifting is one of the forms of recoding that enriches gene expression.
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Affiliation(s)
- John F Atkins
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland School of Microbiology, University College Cork, Cork, Ireland Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Gary Loughran
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - Pramod R Bhatt
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - Andrew E Firth
- Division of Virology, Department of Pathology, University of Cambridge, Hills Road, Cambridge CB2 0QQ, UK
| | - Pavel V Baranov
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
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Baranov PV, Atkins JF, Yordanova MM. Augmented genetic decoding: global, local and temporal alterations of decoding processes and codon meaning. Nat Rev Genet 2015; 16:517-29. [PMID: 26260261 DOI: 10.1038/nrg3963] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The non-universality of the genetic code is now widely appreciated. Codes differ between organisms, and certain genes are known to alter the decoding rules in a site-specific manner. Recently discovered examples of decoding plasticity are particularly spectacular. These examples include organisms and organelles with disruptions of triplet continuity during the translation of many genes, viruses that alter the entire genetic code of their hosts and organisms that adjust their genetic code in response to changing environments. In this Review, we outline various modes of alternative genetic decoding and expand existing terminology to accommodate recently discovered manifestations of this seemingly sophisticated phenomenon.
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Affiliation(s)
- Pavel V Baranov
- School of Biochemistry and Cell Biology, University College Cork, Ireland
| | - John F Atkins
- 1] School of Biochemistry and Cell Biology, University College Cork, Ireland. [2] Department of Human Genetics, University of Utah, 15 N 2030 E Rm. 7410, Salt Lake City, Utah 84112-5330, USA
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27
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Caliskan N, Peske F, Rodnina MV. Changed in translation: mRNA recoding by -1 programmed ribosomal frameshifting. Trends Biochem Sci 2015; 40:265-74. [PMID: 25850333 PMCID: PMC7126180 DOI: 10.1016/j.tibs.2015.03.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 12/19/2022]
Abstract
–1PRF occurs when ribosomes move over a slippery sequence. A frameshifting pseudoknot/stem-loop element stalls ribosomes in a metastable state. –1PRF may contribute to the quality-control machinery in eukaryotes. Trans-acting factors (proteins, miRNAs, or antibiotics) can modulate –1PRF.
Programmed −1 ribosomal frameshifting (−1PRF) is an mRNA recoding event commonly utilized by viruses and bacteria to increase the information content of their genomes. Recent results have implicated −1PRF in quality control of mRNA and DNA stability in eukaryotes. Biophysical experiments demonstrated that the ribosome changes the reading frame while attempting to move over a slippery sequence of the mRNA – when a roadblock formed by a folded downstream segment in the mRNA stalls the ribosome in a metastable conformational state. The efficiency of −1PRF is modulated not only by cis-regulatory elements in the mRNA but also by trans-acting factors such as proteins, miRNAs, and antibiotics. These recent results suggest a molecular mechanism and new important cellular roles for −1PRF.
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Affiliation(s)
- Neva Caliskan
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | - Frank Peske
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | - Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany.
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28
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Henke C, Strissel PL, Schubert MT, Mitchell M, Stolt CC, Faschingbauer F, Beckmann MW, Strick R. Selective expression of sense and antisense transcripts of the sushi-ichi-related retrotransposon--derived family during mouse placentogenesis. Retrovirology 2015; 12:9. [PMID: 25888968 PMCID: PMC4340606 DOI: 10.1186/s12977-015-0138-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 01/07/2015] [Indexed: 01/12/2023] Open
Abstract
Background LTR-retrotransposons became functional neogenes through evolution by acquiring promoter sequences, regulatory elements and sequence modification. Mammalian retrotransposon transcripts (Mart1-9), also called sushi-ichi-related retrotransposon-homolog (SIRH) genes, are a class of Ty3/gypsy LTR-retroelements showing moderate homology to the sushi-ichi LTR-retrotransposon in pufferfish. Rtl1/Mart1 and Peg10/Mart2 expression in mouse placenta and demonstration of their functional roles during placental development exemplifies their importance in cellular processes. In this study, we analyzed all eleven mouse Mart genes from the blastocyst stage and throughout placentogenesis in order to gain information about their expression and regulation. Results Quantitative PCR, in situ hybridization (ISH) and immunoblotting showed various expression patterns of the 11 mouse Mart genes through different placental stages. Zcchc5/Mart3, Zcchc16/ Mart4 and Rgag1/Mart9 expression was undetectable. Rtl1/Mart1, Peg10/Mart2, Rgag4/Mart5 – Cxx1a,b,c/Mart8b,c,a gene expression was very low at the blastocyst stage. Later placental stages showed an increase of expression for Rtl1/Mart1, Rgag4/Mart5 – Cxx1a,b,c/Mart8b,c,a, the latter up to 1,489 molecules/ng cDNA at E9.5. From our recently published findings Peg10/Mart2 was the most highly expressed Mart gene. ISH demonstrated sense and antisense transcript co-localization of Rgag4/Mart5 to Cxx1a,b,c/Mart8b,c,a in trophoblast subtypes at the junctional zone, with an accumulation of antisense transcripts in the nuclei. To validate these results, we developed a TAG-aided sense/antisense transcript detection (TASA-TD) method, which verified sense and antisense transcripts for Rtl1/Mart1, Rgag4/Mart5 – Cxx1a,b,c/Mart8b,c,a. Except for Rtl1/Mart1 and Cxx1a,b/Mart8b,c all other Mart genes showed a reduced amount of antisense transcripts. Northern blot and 5′ and 3′ RACE confirmed both sense and antisense transcripts for Ldoc1/Mart7 and Cxx1a,b,c/Mart8b,c,a. Immunoblotting demonstrated a single protein throughout all placental stages for Ldoc1/Mart7, but for Cxx1a,b,c/Mart8b,c,a a switch occurred from a 57 kDa protein at E10.5 and E14.5 to a 25 kDa protein at E16.5 and E18.5. Conclusions RNA and protein detection of mouse Mart genes support neo-functionalization of retrotransposons in mammalian genomes. Undetectable expression of Zcchc5/Mart3, Zcchc16/Mart4 and Rgag1/Mart9 indicate no role during mouse placentogenesis. Rgag4/Mart5 to Cxx1a,b,c/Mart8b,c,a gene expression support a role for differentiation from the ectoplacental cone. Mart antisense transcripts and protein alterations predict unique and complex molecular regulation in a time directed manner throughout mouse placentogenesis. Electronic supplementary material The online version of this article (doi:10.1186/s12977-015-0138-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Christine Henke
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
| | - Pamela L Strissel
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
| | - Maria-Theresa Schubert
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
| | - Megan Mitchell
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
| | - Claus C Stolt
- Institute of Biochemistry, D-91054, Erlangen, Germany.
| | - Florian Faschingbauer
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
| | - Matthias W Beckmann
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
| | - Reiner Strick
- Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Friedrich-Alexander University Erlangen-Nürnberg (FAU), University-Clinic Erlangen, Erlangen, Germany.
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Advani VM, Belew AT, Dinman JD. Yeast telomere maintenance is globally controlled by programmed ribosomal frameshifting and the nonsense-mediated mRNA decay pathway. ACTA ACUST UNITED AC 2014; 1:e24418. [PMID: 24563826 PMCID: PMC3908577 DOI: 10.4161/trla.24418] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 03/21/2013] [Accepted: 03/22/2013] [Indexed: 11/26/2022]
Abstract
We have previously shown that ~10% of all eukaryotic mRNAs contain potential programmed -1 ribosomal frameshifting (-1 PRF) signals and that some function as mRNA destabilizing elements through the Nonsense-Mediated mRNA Decay (NMD) pathway by directing translating ribosomes to premature termination codons. Here, the connection between -1 PRF, NMD and telomere end maintenance are explored. Functional -1 PRF signals were identified in the mRNAs encoding two components of yeast telomerase, EST1 and EST2, and in mRNAs encoding proteins involved in recruiting telomerase to chromosome ends, STN1 and CDC13. All of these elements responded to mutants and drugs previously known to stimulate or inhibit -1 PRF, further supporting the hypothesis that they promote -1 PRF through the canonical mechanism. All affected the steady-state abundance of a reporter mRNA and the wide range of -1 PRF efficiencies promoted by these elements enabled the determination of an inverse logarithmic relationship between -1 PRF efficiency and mRNA accumulation. Steady-state abundances of the endogenous EST1, EST2, STN1 and CDC13 mRNAs were similarly inversely proportional to changes in -1 PRF efficiency promoted by mutants and drugs, supporting the hypothesis that expression of these genes is post-transcriptionally controlled by -1 PRF under native conditions. Overexpression of EST2 by ablation of -1 PRF signals or inhibition of NMD promoted formation of shorter telomeres and accumulation of large budded cells at the G2/M boundary. A model is presented describing how limitation and maintenance of correct stoichiometries of telomerase components by -1 PRF is used to maintain yeast telomere length.
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Affiliation(s)
- Vivek M Advani
- Department of Cell Biology and Molecular Genetics; University of Maryland; College Park MD, USA
| | - Ashton T Belew
- Department of Cell Biology and Molecular Genetics; University of Maryland; College Park MD, USA
| | - Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics; University of Maryland; College Park MD, USA
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30
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Henke C, Ruebner M, Faschingbauer F, Stolt CC, Schaefer N, Lang N, Beckmann MW, Strissel PL, Strick R. Regulation of murine placentogenesis by the retroviral genes Syncytin-A, Syncytin-B and Peg10. Differentiation 2013; 85:150-60. [PMID: 23807393 DOI: 10.1016/j.diff.2013.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 02/05/2013] [Accepted: 02/06/2013] [Indexed: 01/27/2023]
Abstract
The murine placenta has a trichorial structure with two multinucleated syncytiotrophoblast (SCT) layers representing a barrier between the maternal and fetal blood system. Genes of endogenous retroviruses and retrotransposon-derived paternally expressed genes (Peg), remnants of past infections and integrations in the genome, have essential functions in placentogenesis. Previous studies showed that the envelope genes Syncytin-A and Syncytin-B were essential for cell-cell fusion of the SCT. The goal of this study was to analyze the temporal localization and expression of nine genes throughout placental development from embryonic day (E)8.5 to E18.5 using in situ-hybridization and absolute RNA-quantification. These included a comparison of previously characterized genes from the labyrinth Syncytin-A, Syncytin-B, Gcm1, the junctional zone PL-1, PL-2, Plf, Tpbpa with two further characterized genes Peg10 and Tpbpb. Syncytin-A and Syncytin-B RNA localized to SCT-I and SCT-II, respectively. Peg10 RNA localized to all extraembryonic tissues, specifically to the parietal and sinusoidal TGC of the labyrinth layer, which is in contact with SCT-I and the maternal blood. All three retroviral/retrotransposon-derived genes showed the highest expression at E16.5, but Peg10 with 188,917.1 molecules/ng cDNA was 208-fold and 106.8-fold higher expressed than Syncytin-A and Syncytin-B, respectively. Tpbpb localized to the junctional zone and showed the highest expression at E16.5 along with PL-2, Plf, Tpbpa, but not PL-1, which decreased in expression at E10.5. To investigate a role of Syncytin-A, Syncytin-B and Peg10 in cell-cell fusion, we established a cell culture system with fractionated primary trophoblasts from murine placentae. Culturing trophoblasts for up to 72h partly resembled trophoblast development in vivo according to the nine marker genes. Knockdown of Syncytin-A demonstrated a functional regulation of cell-cell fusion, where knockdown of Peg10 showed no involvement in cell fusion. Due to the expression of Peg10 in TGCs, we propose an essential functional role in the fetal-maternal blood system.
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Affiliation(s)
- Christine Henke
- University-Clinic Erlangen, Department of Gynaecology and Obstetrics, Laboratory for Molecular Medicine, Universitaetsstr. 21-23, D-91054 Erlangen, Germany
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31
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Mauger DM, Siegfried NA, Weeks KM. The genetic code as expressed through relationships between mRNA structure and protein function. FEBS Lett 2013; 587:1180-1188. [PMID: 23499436 PMCID: PMC4269304 DOI: 10.1016/j.febslet.2013.03.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 02/28/2013] [Accepted: 03/01/2013] [Indexed: 02/05/2023]
Abstract
Structured RNA elements within messenger RNA often direct or modulate the cellular production of active proteins. As reviewed here, RNA structures have been discovered that govern nearly every step in protein production: mRNA production and stability; translation initiation, elongation, and termination; protein folding; and cellular localization. Regulatory RNA elements are common within RNAs from every domain of life. This growing body of RNA-mediated mechanisms continues to reveal new ways in which mRNA structure regulates translation. We integrate examples from several different classes of RNA structure-mediated regulation to present a global perspective that suggests that the secondary and tertiary structure of RNA ultimately constitutes an additional level of the genetic code that both guides and regulates protein biosynthesis.
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Affiliation(s)
- David M Mauger
- Department of Chemistry, University of North Carolina Chapel Hill, North Carolina, USA 25599-3290
| | - Nathan A Siegfried
- Department of Chemistry, University of North Carolina Chapel Hill, North Carolina, USA 25599-3290
| | - Kevin M Weeks
- Department of Chemistry, University of North Carolina Chapel Hill, North Carolina, USA 25599-3290
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32
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Hekman KE, Yu GY, Brown CD, Zhu H, Du X, Gervin K, Undlien DE, Peterson A, Stevanin G, Clark HB, Pulst SM, Bird TD, White KP, Gomez CM. A conserved eEF2 coding variant in SCA26 leads to loss of translational fidelity and increased susceptibility to proteostatic insult. Hum Mol Genet 2012; 21:5472-83. [PMID: 23001565 DOI: 10.1093/hmg/dds392] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The autosomal dominant spinocerebellar ataxias (SCAs) are a genetically heterogeneous group of disorders exhibiting cerebellar atrophy and Purkinje cell degeneration whose subtypes arise from 31 distinct genetic loci. Our group previously published the locus for SCA26 on chromosome 19p13.3. In this study, we performed targeted deep sequencing of the critical interval in order to identify candidate causative variants in individuals from the SCA26 family. We identified a single variant that co-segregates with the disease phenotype that produces a single amino acid substitution in eukaryotic elongation factor 2. This substitution, P596H, sits in a domain critical for maintaining reading frame during translation. The yeast equivalent, P580H EF2, demonstrated impaired translocation, detected as an increased rate of -1 programmed ribosomal frameshift read-through in a dual-luciferase assay for observing translational recoding. This substitution also results in a greater susceptibility to proteostatic disruption, as evidenced by a more robust activation of a reporter gene driven by unfolded protein response activation upon challenge with dithiothreitol or heat shock in our yeast model system. Our results present a compelling candidate mutation and mechanism for the pathogenesis of SCA26 and further support the role of proteostatic disruption in neurodegenerative diseases.
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Affiliation(s)
- Katherine E Hekman
- Department of Neurology, Institute for Genomics and Systems Biology, University of Chicago, Chicago, IL 60637, USA
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Lu Y, Zhang Y, Hang X, Qu W, Lubec G, Chen C, Zhang C. Genome-wide computational identification of bicistronic mRNA in humans. Amino Acids 2012; 44:597-606. [PMID: 22945903 DOI: 10.1007/s00726-012-1380-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Accepted: 07/26/2012] [Indexed: 11/30/2022]
Abstract
Mammalian bicistronic mRNA is a recently discovered mammalian gene structure. Several reported cases of mammalian bicistronic mRNA indicated that genes of this structure play roles in some important biological processes. However, a genome-wide computational identification of bicistronic mRNA in mammalian genome, such as human genome, is still lacking. Here we used a comparative genomics approach to identify the frequency of human bicistronic mRNA. We then validated the result by using a new support vector machine (SVM) model. We identified 43 human bicistronic mRNAs in 30 distinct genes. Our literature analysis shows that our method recovered 100 % (6/6) of the previously known bicistronic mRNAs which had been experimentally confirmed by other groups. Our graph theory-based analysis and GO analysis indicated that human bicistronic mRNAs are prone to produce different yet closely functionally related proteins. In addition, we also described and analyzed three different mechanisms of ORF fusion. Our method of identifying bicistronic mRNAs in human genome provides a model for the computational identification of characteristic gene structures in mammalian genomes. We anticipate that our data will facilitate further molecular characterization and functional study of human bicistronic mRNA.
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Affiliation(s)
- Yiming Lu
- Beijing Institute of Radiation Medicine, State Key Laboratory of Proteomics, Cognitive and Mental Health Research Center, Beijing 100850, China
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Kaneko-Ishino T, Ishino F. The role of genes domesticated from LTR retrotransposons and retroviruses in mammals. Front Microbiol 2012; 3:262. [PMID: 22866050 PMCID: PMC3406341 DOI: 10.3389/fmicb.2012.00262] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Accepted: 07/04/2012] [Indexed: 12/31/2022] Open
Abstract
The acquisition of multiple genes from long terminal repeat (LTR) retrotransposons occurred in mammals. Genes belonging to a sushi-ichi-related retrotransposon homologs (SIRH) family emerged around the time of the establishment of two viviparous mammalian groups, marsupials and eutherians. These genes encode proteins that are homologous to a retrotransposon Gag capsid protein and sometimes also have a Pol-like region. We previously demonstrated that PEG10 (SIRH1) and PEG11/RTL1 (SIRH2) play essential but different roles in placental development. PEG10 is conserved in both the marsupials and the eutherians, while PEG11/RTL1 is a eutherian-specific gene, suggesting that these two domesticated genes were deeply involved in the evolution of mammals via the establishment of the viviparous reproduction system. In this review, we introduce the roles of PEG10 and PEG11/RTL1 in mammalian development and evolution, and summarize the other genes domesticated from LTR retrotransposons and endogenous retroviruses (ERVs) in mammals. We also point out the importance of DNA methylation in inactivating and neutralizing the integrated retrotransposons and ERVs in the process of domestication.
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Dinman JD. Control of gene expression by translational recoding. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2012; 86:129-49. [PMID: 22243583 PMCID: PMC7149833 DOI: 10.1016/b978-0-12-386497-0.00004-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Like all rules, even the genetic code has exceptions: these are generically classified as “translational recoding.” Almost every conceivable mode of recoding has been documented, including signals that redefine translational reading frame and codon assignation. While first described in viruses, it is becoming clear that sequences that program elongating ribosomes to shift translational reading frame are widely used by organisms in all domains of life, thus expanding both the coding capacity of genomes and the modes through which gene expression can be regulated at the posttranscriptional level. Instances of programmed ribosomal frameshifting and stop codon reassignment are opening up new avenues for treatment of numerous inborn errors of metabolism. The implications of these findings on human health are only beginning to emerge.
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Affiliation(s)
- Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
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Dinman JD. Mechanisms and implications of programmed translational frameshifting. WILEY INTERDISCIPLINARY REVIEWS-RNA 2012; 3:661-73. [PMID: 22715123 PMCID: PMC3419312 DOI: 10.1002/wrna.1126] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
While ribosomes must maintain translational reading frame in order to translate primary genetic information into polypeptides, cis‐acting signals located in mRNAs represent higher order information content that can be used to fine‐tune gene expression. Classes of signals have been identified that direct a fraction of elongating ribosomes to shift reading frame by one base in the 5′ (−1) or 3′ (+1) direction. This is called programmed ribosomal frameshifting (PRF). Although mechanisms of PRF differ, a common feature is induction of ribosome pausing, which alters kinetic partitioning rates between in‐frame and out‐of‐frame codons at specific ‘slippery’ sequences. Many viruses use PRF to ensure synthesis of the correct ratios of virus‐encoded proteins required for proper viral particle assembly and maturation, thus identifying PRF as an attractive target for antiviral therapeutics. In contrast, recent studies indicate that PRF signals may primarily function as mRNA destabilizing elements in cellular mRNAs. These studies suggest that PRF may be used to fine‐tune gene expression through mRNA decay pathways. The possible regulation of PRF by noncoding RNAs is also discussed. WIREs RNA 2012 doi: 10.1002/wrna.1126 This article is categorized under:
RNA Structure and Dynamics > Influence of RNA Structure in Biological Systems RNA Evolution and Genomics > Computational Analyses of RNA Translation > Translation Regulation
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Affiliation(s)
- Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, USA.
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Michel AM, Choudhury KR, Firth AE, Ingolia NT, Atkins JF, Baranov PV. Observation of dually decoded regions of the human genome using ribosome profiling data. Genome Res 2012; 22:2219-29. [PMID: 22593554 PMCID: PMC3483551 DOI: 10.1101/gr.133249.111] [Citation(s) in RCA: 151] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The recently developed ribosome profiling technique (Ribo-Seq) allows mapping of the locations of translating ribosomes on mRNAs with subcodon precision. When ribosome protected fragments (RPFs) are aligned to mRNA, a characteristic triplet periodicity pattern is revealed. We utilized the triplet periodicity of RPFs to develop a computational method for detecting transitions between reading frames that occur during programmed ribosomal frameshifting or in dual coding regions where the same nucleotide sequence codes for multiple proteins in different reading frames. Application of this method to ribosome profiling data obtained for human cells allowed us to detect several human genes where the same genomic segment is translated in more than one reading frame (from different transcripts as well as from the same mRNA) and revealed the translation of hitherto unpredicted coding open reading frames.
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Ono R, Kuroki Y, Naruse M, Ishii M, Iwasaki S, Toyoda A, Fujiyama A, Shaw G, Renfree MB, Kaneko-Ishino T, Ishino F. Identification of tammar wallaby SIRH12, derived from a marsupial-specific retrotransposition event. DNA Res 2011; 18:211-9. [PMID: 21636603 PMCID: PMC3158469 DOI: 10.1093/dnares/dsr012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
In humans and mice, there are 11 genes derived from sushi-ichi related retrotransposons, some of which are known to play essential roles in placental development. Interestingly, this family of retrotransposons was thought to exist only in eutherian mammals, indicating their significant contributions to the eutherian evolution, but at least one, PEG10, is conserved between marsupials and eutherians. Here we report a novel sushi-ichi retrotransposon-derived gene, SIRH12, in the tammar wallaby, an Australian marsupial species of the kangaroo family. SIRH12 encodes a protein highly homologous to the sushi-ichi retrotransposon Gag protein in the tammar wallaby, while SIRH12 in the South American short-tailed grey opossum is a pseudogene degenerated by accumulation of multiple nonsense mutations. This suggests that SIRH12 retrotransposition occurred only in the marsupial lineage but acquired and retained some as yet unidentified novel function, at least in the lineage of the tammar wallaby.
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Affiliation(s)
- Ryuichi Ono
- Department of Epigenetics, Medical Research Institute, Tokyo Medical and Dental University, Yushima, Bunkyo-ku, Japan
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39
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John RM, Lefebvre L. Developmental regulation of somatic imprints. Differentiation 2011; 81:270-80. [DOI: 10.1016/j.diff.2011.01.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 12/16/2010] [Accepted: 01/11/2011] [Indexed: 12/21/2022]
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40
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Abstract
Errors occur randomly and at low frequency during the translation of mRNA. However, such errors may also be programmed by the sequence and structure of the mRNA. These programmed events are called ‘recoding’ and are found mostly in viruses, in which they are usually essential for viral replication. Translational errors at a stop codon may also be induced by drugs, raising the possibility of developing new treatment protocols for genetic diseases on the basis of nonsense mutations. Many studies have been carried out, but the molecular mechanisms governing these events remain largely unknown. Studies on the yeast Saccharomyces cerevisiae have contributed to characterization of the HIV‐1 frameshifting site and have demonstrated that frameshifting is conserved from yeast to humans. Yeast has also proved a particularly useful model organism for deciphering the mechanisms of translation termination in eukaryotes and identifying the factors required to obtain a high level of natural suppression. These findings open up new possibilities for large‐scale screening in yeast to identify new drugs for blocking HIV replication by inhibiting frameshifting or restoring production of the full‐length protein from a gene inactivated by a premature termination codon. We explore these two aspects of the contribution of yeast studies to human medicine in this review.
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Affiliation(s)
- Laure Bidou
- Université Paris-Sud, IGM CNRS UMR 8621, Orsay, France
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41
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Whiteley NM, Magnay JL, McCleary SJ, Nia SK, El Haj AJ, Rock J. Characterisation of myosin heavy chain gene variants in the fast and slow muscle fibres of gammarid amphipods. Comp Biochem Physiol A Mol Integr Physiol 2010; 157:116-22. [PMID: 20570748 DOI: 10.1016/j.cbpa.2010.05.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 05/23/2010] [Accepted: 05/24/2010] [Indexed: 10/19/2022]
Abstract
Recent molecular work has revealed a large diversity of myosin heavy chain (MyHC) gene variants in the abdominal musculature of gammarid amphipods. An unusual truncated MyHC transcript from the loop 1 region (Variant A(3)) was consistently observed in multiple species and populations. The current study aimed to determine whether this MyHC variant is specific to a particular muscle fibre type, as a change in net charge to the loop 1 region of Variant A(3) could be functionally significant. The localisation of different fibre types within the abdominal musculature of several gammarid species revealed that the deep flexor and extensor muscles are fast-twitch muscle fibres. The dorsal superficial muscles were identified as slow fibres and the muscles extrinsic to the pleopods were identified as intermediate fibres. Amplification of loop 1 region mRNA from isolated superficial extensor and deep flexor muscles, and subsequent liquid chromatography and sequence analysis revealed that Variant A(3) was the primary MyHC variant in slow muscles, and the conserved A(1) sequence was the primary variant in fast muscles. The specific role of Variant A(3) in the slow muscles remains to be investigated.
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Kobayashi Y, Zhuang J, Peltz S, Dougherty J. Identification of a cellular factor that modulates HIV-1 programmed ribosomal frameshifting. J Biol Chem 2010; 285:19776-84. [PMID: 20418372 DOI: 10.1074/jbc.m109.085621] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Programmed -1 ribosomal frameshifting (PRF) is a distinctive mode of gene expression utilized by some viruses, including human immunodeficiency virus type 1 (HIV-1), to produce multiple proteins from a single mRNA. -1 PRF induces a subset of elongating ribosomes to shift their translational reading frame by 1 base in the 5' direction. The appropriate ratio of Gag to Gag-Pol synthesis is tightly regulated by the PRF signal which promotes ribosomes to shift frame, and even small changes in PRF efficiency, either up or down, have significant inhibitory effects upon virus production, making PRF essential for HIV-1 replication. Although little has been reported about the cellular factors that modulate HIV-1 PRF, the cis-acting elements regulating PRF have been extensively investigated, and the PRF signal of HIV-1 was shown to include a slippery site and frameshift stimulatory signal. Recently, a genome-wide screen performed to identify cellular factors that affect HIV-1 replication demonstrated that down-regulation of eukaryotic release factor 1 (eRF1) inhibited HIV-1 replication. Because of the eRF1 role in translation, we hypothesized that eRF1 is important for HIV-1 PRF. Using a dual luciferase reporter system harboring a HIV-1 PRF signal, results showed that depletion or inhibition of eRF1 enhanced PRF in yeast, rabbit reticulocyte lysates, and mammalian cells. Consistent with the eRF1 role in modulating HIV PRF, depleting eRF1 increased the Gag-Pol to Gag ratio in cells infected with replication-competent virus. The increase in PRF was independent of a proximal termination codon and did not result from increased ribosomal pausing at the slippery site. This is the first time that a cellular factor has been identified which can promote HIV-1 PRF and highlights HIV-1 PRF as essential for replication and an important but under exploited antiviral drug target.
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Affiliation(s)
- Yoshifumi Kobayashi
- Department of Molecular Genetics, Microbiology and Immunology, University of Medicine and Dentistry of New Jersey Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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43
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Lux H, Flammann H, Hafner M, Lux A. Genetic and molecular analyses of PEG10 reveal new aspects of genomic organization, transcription and translation. PLoS One 2010; 5:e8686. [PMID: 20084274 PMCID: PMC2800197 DOI: 10.1371/journal.pone.0008686] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 12/22/2009] [Indexed: 11/19/2022] Open
Abstract
The paternally expressed gene PEG10 is a retrotransposon derived gene adapted through mammalian evolution located on human chromosome 7q21. PEG10 codes for at least two proteins, PEG10-RF1 and PEG10-RF1/2, by -1 frameshift translation. Overexpression or reinduced PEG10 expression was seen in malignancies, like hepatocellular carcinoma or B-cell acute and chronic lymphocytic leukemia. PEG10 was also shown to promote adipocyte differentiation. Experimental evidence suggests that the PEG10-RF1 protein is an inhibitor of apoptosis and mediates cell proliferation. Here we present new data on the genomic organization of PEG10 by identifying the major transcription start site, a new splice variant and report the cloning and analysis of 1.9 kb of the PEG10 promoter. Furthermore, we show for the first time that PEG10 translation is initiated at a non-AUG start codon upstream of the previously predicted AUG codon as well as at the AUG codon. The finding that PEG10 translation is initiated at different sides adds a new aspect to the already interesting feature of PEG10's -1 frameshift translation mechanism. It is now important to unravel the cellular functions of the PEG10 protein variants and how they are related to normal or pathological conditions. The generated promoter-reporter constructs can be used for future studies to investigate how PEG10 expression is regulated. In summary, our study provides new data on the genomic organization as well as expression and translation of PEG10, a prerequisite in order to study and understand the role of PEG10 in cancer, embryonic development and normal cell homeostasis.
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Affiliation(s)
- Heike Lux
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences, Mannheim, Germany
| | - Heiko Flammann
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences, Mannheim, Germany
| | - Mathias Hafner
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences, Mannheim, Germany
- Faculty of Medicine at Mannheim, University of Heidelberg, Mannheim, Germany
| | - Andreas Lux
- Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences, Mannheim, Germany
- Faculty of Medicine at Mannheim, University of Heidelberg, Mannheim, Germany
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Atkins JF, Gesteland RF, Pennell S. Pseudoknot-Dependent Programmed —1 Ribosomal Frameshifting: Structures, Mechanisms and Models. RECODING: EXPANSION OF DECODING RULES ENRICHES GENE EXPRESSION 2009; 24. [PMCID: PMC7119991 DOI: 10.1007/978-0-387-89382-2_7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Programmed —1 ribosomal frameshifting is a translational recoding strategy that takes place during the elongation phase of protein biosynthesis. Frameshifting occurs in response to specific signals in the mRNA; a slippery sequence, where the ribosome changes frame, and a stimulatory RNA secondary structure, usually a pseudoknot, located immediately downstream. During the frameshift the ribosome slips backwards by a single nucleotide (in the 5′-wards/—1 direction) and continues translation in the new, overlapping reading frame, generating a fusion protein composed of the products of both the original and the —1 frame coding regions. In eukaryotes, frameshifting is largely a phenomenon of virus gene expression and associated predominantly with the expression of viral replicases. Research on frameshifting impacts upon diverse topics, including the ribosomal elongation cycle, RNA structure and function, tRNA modification, virus replication, antiviral intervention, evolution and bioinformatics. This chapter focuses on the structure and function of frameshift-stimulatory RNA pseudoknots and mechanistic aspects of ribosomal frameshifting. A variety of models of the frameshifting process are discussed in the light of recent advances in our understanding of ribosome structure and the elongation cycle.
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Affiliation(s)
- John F. Atkins
- grid.223827.e0000000121930096Molecular Biology Program, University of Utah, N. 2030 E. 15, Salt Late City, 84112-5330 U.S.A.
| | - Raymond F. Gesteland
- grid.223827.e0000000121930096Dept. Bioengineering, University of Utah, Salt Lake City, 84112 U.S.A.
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Linking functional molecular variation with environmental gradients: Myosin gene diversity in a crustacean broadly distributed across variable thermal environments. Gene 2009; 437:60-70. [DOI: 10.1016/j.gene.2009.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2008] [Revised: 01/09/2009] [Accepted: 02/07/2009] [Indexed: 11/19/2022]
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46
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Abstract
Viruses are adept at evolving or co-opting genomic elements that allow them to maximize their replication potential in the infected host. This evolutionary plasticity makes viruses an invaluable system to identify new mechanisms used not only by viruses but also by vertebrate cells to modulate gene expression. Here, I discuss the identification and characterization of viral mRNA structures and noncoding RNAs that have led to important insights into the molecular mechanisms of eukaryotic cells.
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Affiliation(s)
- Bryan R Cullen
- Department of Molecular Genetics & Microbiology, Center for Virology, Duke University Medical Center, Durham, NC 27710, USA.
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Clark MB, Jänicke M, Gottesbühren U, Kleffmann T, Legge M, Poole ES, Tate WP. Mammalian Gene PEG10 Expresses Two Reading Frames by High Efficiency –1 Frameshifting in Embryonic-associated Tissues. J Biol Chem 2007; 282:37359-69. [DOI: 10.1074/jbc.m705676200] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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48
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Brierley I, Pennell S, Gilbert RJC. Viral RNA pseudoknots: versatile motifs in gene expression and replication. Nat Rev Microbiol 2007; 5:598-610. [PMID: 17632571 PMCID: PMC7096944 DOI: 10.1038/nrmicro1704] [Citation(s) in RCA: 139] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
RNA pseudoknots are structural motifs in RNA that are increasingly recognized in viral and cellular RNAs. They have been shown to have a various roles in virus and cellular gene expression. Pseudoknots are formed upon base pairing of a single-stranded region of RNA in the loop of a hairpin to a stretch of complementary nucleotides elsewhere in the RNA chain. This simple folding strategy can generate a large number of stable three-dimensional folds, which display a diverse range of highly specific functions. Pseudoknot function is frequently associated with interactions with ribosomes. The inclusion of pseudoknots in an mRNA can thus confer unusual translational properties. Many RNA viruses use pseudoknots in the control of viral RNA translation, replication and the switch between the two processes. Some satellite viruses encode ribozymes with active sites that are folded by a pseudoknot. In cellular RNAs, pseudoknots are associated with all aspects of mRNA function and also ribosome function, as ribosomal RNAs contain numerous pseudoknots. Other essential cellular pseudoknots have been described in telomerase RNA and transfer messenger RNA. Future research into pseudoknots will focus on structure–function relationships and bioinformatics identification of pseudoknots in genomes. The use of pseudoknots in antiviral applications could also become more widespread.
RNA pseudoknots have been identified in many different viral and cellular RNAs and are known to have various roles in virus and cellular gene expression. Here, Ian Brierley and colleagues review viral pseudoknots and the role of these structural motifs in virus gene expression and genome replication. RNA pseudoknots are structural elements found in almost all classes of RNA. First recognized in the genomes of plant viruses, they are now established as a widespread motif with diverse functions in various biological processes. This Review focuses on viral pseudoknots and their role in virus gene expression and genome replication. Although emphasis is placed on those well defined pseudoknots that are involved in unusual mechanisms of viral translational initiation and elongation, the broader roles of pseudoknots are also discussed, including comparisons with relevant cellular counterparts. The relationship between RNA pseudoknot structure and function is also addressed.
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Affiliation(s)
- Ian Brierley
- Division of Virology, Department of Pathology, University of Cambridge, Tennis Court Road, CB2 1QP Cambridge UK
| | - Simon Pennell
- Division of Molecular Structure, National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA UK
| | - Robert J. C. Gilbert
- Division of Structural Biology, Henry Wellcome Building for Genomic Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN UK
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49
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Volff JN. Turning junk into gold: domestication of transposable elements and the creation of new genes in eukaryotes. Bioessays 2007; 28:913-22. [PMID: 16937363 DOI: 10.1002/bies.20452] [Citation(s) in RCA: 266] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Autonomous transposable elements, generally considered as junk and selfish, encode transposition proteins that can bind, copy, break, join or degrade nucleic acids as well as process or interact with other proteins. Such a repertoire of activities might be of interest for the host cell. There is indeed substantial evidence that mobile DNA can serve as a dynamic reservoir for new cellular functions. Transposable element genes encoding transposase, integrase, reverse transcriptase as well as structural and envelope proteins have been repeatedly recruited by their host during evolution in most eukaryotic lineages. Such domesticated sequences protect us against infections, are necessary for our reproduction, allow the replication of our chromosomes and control cell proliferation and death; others are essential for plant development. Many new candidates for domesticated sequences have been revealed by sequencing projects. Their functional analysis will uncover new aspects of evolutionary alchemy, the turning of junk into gold within genomes.
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Affiliation(s)
- Jean-Nicolas Volff
- Biofuture Research Group, Physiologische Chemie I, Biozentrum, University of Würzburg, am Hubland, D-97074 Würzburg, Germany.
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50
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Ho O, Green WR. Alternative translational products and cryptic T cell epitopes: expecting the unexpected. THE JOURNAL OF IMMUNOLOGY 2007; 177:8283-9. [PMID: 17142722 DOI: 10.4049/jimmunol.177.12.8283] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Although CD8 T cell epitopes have been studied extensively, often overlooked are unconventional cryptic epitopes generated from nontraditional sources of peptides/proteins and/or mechanisms of translation. In this review, we discuss alternative reading frame epitopes, both mechanistically and also in terms of their physiologic importance in the induction of antiviral and antitumor CTL responses. Issues of the influence of cryptic translational products on foreign and self-Ag diversity, thymic selection, and the T cell repertoire; disease pathogenesis; and approaches to vaccine design are discussed in context of the potentially large impact of unconventional epitopes on T cell immunity.
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Affiliation(s)
- On Ho
- Department of Microbiology and Immunology, Dartmouth Medical School, One Medical Center Drive, Lebanon, NH 03756, USA
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