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Yerlici VT, Astori A, Kejiou NS, Jordan CA, Khosraviani N, Chan JNY, Hakem R, Raught B, Palazzo AF, Mekhail K. SARS-CoV-2 targets ribosomal RNA biogenesis. Cell Rep 2024; 43:113891. [PMID: 38427561 DOI: 10.1016/j.celrep.2024.113891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 10/02/2023] [Accepted: 02/15/2024] [Indexed: 03/03/2024] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) hinders host gene expression, curbing defenses and licensing viral protein synthesis and virulence. During SARS-CoV-2 infection, the virulence factor non-structural protein 1 (Nsp1) targets the mRNA entry channel of mature cytoplasmic ribosomes, limiting translation. We show that Nsp1 also restrains translation by targeting nucleolar ribosome biogenesis. SARS-CoV-2 infection disrupts 18S and 28S ribosomal RNA (rRNA) processing. Expression of Nsp1 recapitulates the processing defects. Nsp1 abrogates rRNA production without altering the expression of critical processing factors or nucleolar organization. Instead, Nsp1 localizes to the nucleolus, interacting with precursor-rRNA and hindering its maturation separately from the viral protein's role in restricting mature ribosomes. Thus, SARS-CoV-2 Nsp1 limits translation by targeting ribosome biogenesis and mature ribosomes. These findings revise our understanding of how SARS-CoV-2 Nsp1 controls human protein synthesis, suggesting that efforts to counter Nsp1's effect on translation should consider the protein's impact from ribosome manufacturing to mature ribosomes.
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Affiliation(s)
- V Talya Yerlici
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Audrey Astori
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada
| | - Nevraj S Kejiou
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Chris A Jordan
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Negin Khosraviani
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Janet N Y Chan
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Razqallah Hakem
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada; Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Medical Biophysics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Brian Raught
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 1L7, Canada; Department of Medical Biophysics, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1L7, Canada
| | - Alexander F Palazzo
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Karim Mekhail
- Department of Laboratory Medicine and Pathobiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5G 1M1, Canada.
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Lytic Reactivation of the Kaposi’s Sarcoma-Associated Herpesvirus (KSHV) Is Accompanied by Major Nucleolar Alterations. Viruses 2022; 14:v14081720. [PMID: 36016343 PMCID: PMC9412354 DOI: 10.3390/v14081720] [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: 06/14/2022] [Revised: 07/21/2022] [Accepted: 07/28/2022] [Indexed: 02/01/2023] Open
Abstract
The nucleolus is a subnuclear compartment whose primary function is the biogenesis of ribosomal subunits. Certain viral infections affect the morphology and composition of the nucleolar compartment and influence ribosomal RNA (rRNA) transcription and maturation. However, no description of nucleolar morphology and function during infection with Kaposi’s sarcoma-associated herpesvirus (KSHV) is available to date. Using immunofluorescence microscopy, we documented extensive destruction of the nuclear and nucleolar architecture during the lytic reactivation of KSHV. This was manifested by the redistribution of key nucleolar proteins, including the rRNA transcription factor UBF. Distinct delocalization patterns were evident; certain nucleolar proteins remained together whereas others dissociated, implying that nucleolar proteins undergo nonrandom programmed dispersion. Significantly, the redistribution of UBF was dependent on viral DNA replication or late viral gene expression. No significant changes in pre-rRNA levels and no accumulation of pre-rRNA intermediates were found by RT-qPCR and Northern blot analysis. Furthermore, fluorescent in situ hybridization (FISH), combined with immunofluorescence, revealed an overlap between Fibrillarin and internal transcribed spacer 1 (ITS1), which represents the primary product of the pre-rRNA, suggesting that the processing of rRNA proceeds during lytic reactivation. Finally, small changes in the levels of pseudouridylation (Ψ) and 2′-O-methylation (Nm) were documented across the rRNA; however, none were localized to the functional domain. Taken together, our results suggest that despite dramatic changes in the nucleolar organization, rRNA transcription and processing persist during lytic reactivation of KSHV. Whether the observed nucleolar alterations favor productive infection or signify cellular anti-viral responses remains to be determined.
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Alvarado-Hernandez B, Ma Y, Sharma NR, Majerciak V, Lobanov A, Cam M, Zhu J, Zheng ZM. Protein-RNA Interactome Analysis Reveals Wide Association of Kaposi's Sarcoma-Associated Herpesvirus ORF57 with Host Noncoding RNAs and Polysomes. J Virol 2022; 96:e0178221. [PMID: 34787459 PMCID: PMC8826805 DOI: 10.1128/jvi.01782-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 11/07/2021] [Indexed: 12/15/2022] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) ORF57 is an RNA-binding posttranscriptional regulator. We recently applied an affinity-purified anti-ORF57 antibody to conduct ORF57 cross-linking immunoprecipitation (CLIP) in combination with RNA-sequencing (CLIP-seq) and analyzed the genome-wide host RNA transcripts in association with ORF57 in BCBL-1 cells with lytic KSHV infection. Mapping of the CLIP RNA reads to the human genome (GRCh37) revealed that most of the ORF57-associated RNA reads were from rRNAs. The remaining RNA reads mapped to several classes of host noncoding and protein-coding mRNAs. We found that ORF57 binds and regulates expression of a subset of host long noncoding RNAs (lncRNAs), including LINC00324, LINC00355, and LINC00839, which are involved in cell growth. ORF57 binds small nucleolar RNAs (snoRNAs) responsible for 18S and 28S rRNA modifications but does not interact with fibrillarin or NOP58. We validated ORF57 interactions with 67 snoRNAs by ORF57 RNA immunoprecipitation (RIP)-snoRNA array assays. Most of the identified ORF57 rRNA binding sites (BS) overlap the sites binding snoRNAs. We confirmed ORF57-snoRA71B RNA interaction in BCBL-1 cells by ORF57 RIP and Northern blot analyses using a 32P-labeled oligonucleotide probe from the 18S rRNA region complementary to snoRA71B. Using RNA oligonucleotides from the rRNA regions that ORF57 binds for oligonucleotide pulldown-Western blot assays, we selectively verified ORF57 interactions with 5.8S and 18S rRNAs. Polysome profiling revealed that ORF57 associates with both monosomes and polysomes and that its association with polysomes increases PABPC1 binding to polysomes but prevents Ago2 association with polysomes. Our data indicate a functional correlation with ORF57 binding and suppression of Ago2 activities for ORF57 promotion of gene expression. IMPORTANCE As an RNA-binding protein, KSHV ORF57 regulates RNA splicing, stability, and translation and inhibits host innate immunity by blocking the formation of RNA granules in virus-infected cells. In this study, ORF57 was found to interact with many host noncoding RNAs, including lncRNAs, snoRNAs, and rRNAs, to carry out additional unknown functions. ORF57 binds a group of lncRNAs via the RNA motifs identified by ORF57 CLIP-seq to regulate their expression. ORF57 associates with snoRNAs independently of fibrillarin and NOP58 proteins and with rRNA in the regions that commonly bind snoRNAs. Knockdown of fibrillarin expression decreases the expression of snoRNAs and CDK4 but does not affect viral gene expression. More importantly, we found that ORF57 binds translationally active polysomes and enhances PABPC1 but prevents Ago2 association with polysomes. Data provide compelling evidence on how ORF57 in KSHV-infected cells might regulate protein synthesis by blocking Ago2's hostile activities on translation.
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Affiliation(s)
- Beatriz Alvarado-Hernandez
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, Maryland, USA
| | - Yanping Ma
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, Maryland, USA
| | - Nishi R. Sharma
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, Maryland, USA
| | - Vladimir Majerciak
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, Maryland, USA
| | - Alexei Lobanov
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, NCI/NIH, Bethesda, Maryland, USA
| | - Maggie Cam
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, NCI/NIH, Bethesda, Maryland, USA
| | - Jun Zhu
- Genome Technology Laboratory, System Biology Center, NHLBI/NIH, Bethesda, Maryland, USA
| | - Zhi-Ming Zheng
- Tumor Virus RNA Biology Section, HIV Dynamics and Replication Program, Center for Cancer Research, NCI/NIH, Frederick, Maryland, USA
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Iarovaia OV, Ioudinkova ES, Velichko AK, Razin SV. Manipulation of Cellular Processes via Nucleolus Hijaking in the Course of Viral Infection in Mammals. Cells 2021; 10:cells10071597. [PMID: 34202380 PMCID: PMC8303250 DOI: 10.3390/cells10071597] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/16/2022] Open
Abstract
Due to their exceptional simplicity of organization, viruses rely on the resources, molecular mechanisms, macromolecular complexes, regulatory pathways, and functional compartments of the host cell for an effective infection process. The nucleolus plays an important role in the process of interaction between the virus and the infected cell. The interactions of viral proteins and nucleic acids with the nucleolus during the infection process are universal phenomena and have been described for almost all taxonomic groups. During infection, proteins of the nucleolus in association with viral components can be directly used for the processes of replication and transcription of viral nucleic acids and the assembly and transport of viral particles. In the course of a viral infection, the usurpation of the nucleolus functions occurs and the usurpation is accompanied by profound changes in ribosome biogenesis. Recent studies have demonstrated that the nucleolus is a multifunctional and dynamic compartment. In addition to the biogenesis of ribosomes, it is involved in regulating the cell cycle and apoptosis, responding to cellular stress, repairing DNA, and transcribing RNA polymerase II-dependent genes. A viral infection can be accompanied by targeted transport of viral proteins to the nucleolus, massive release of resident proteins of the nucleolus into the nucleoplasm and cytoplasm, the movement of non-nucleolar proteins into the nucleolar compartment, and the temporary localization of viral nucleic acids in the nucleolus. The interaction of viral and nucleolar proteins interferes with canonical and non-canonical functions of the nucleolus and results in a change in the physiology of the host cell: cell cycle arrest, intensification or arrest of ribosome biogenesis, induction or inhibition of apoptosis, and the modification of signaling cascades involved in the stress response. The nucleolus is, therefore, an important target during viral infection. In this review, we discuss the functional impact of viral proteins and nucleic acid interaction with the nucleolus during infection.
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Selinger M, Tykalová H, Štěrba J, Věchtová P, Vavrušková Z, Lieskovská J, Kohl A, Schnettler E, Grubhoffer L. Tick-borne encephalitis virus inhibits rRNA synthesis and host protein production in human cells of neural origin. PLoS Negl Trop Dis 2019; 13:e0007745. [PMID: 31560682 PMCID: PMC6785130 DOI: 10.1371/journal.pntd.0007745] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 10/09/2019] [Accepted: 09/03/2019] [Indexed: 12/11/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV), a member of the genus Flavivirus (Flaviviridae), is a causative agent of a severe neuroinfection. Recently, several flaviviruses have been shown to interact with host protein synthesis. In order to determine whether TBEV interacts with this host process in its natural target cells, we analysed de novo protein synthesis in a human cell line derived from cerebellar medulloblastoma (DAOY HTB-186). We observed a significant decrease in the rate of host protein synthesis, including the housekeeping genes HPRT1 and GAPDH and the known interferon-stimulated gene viperin. In addition, TBEV infection resulted in a specific decrease of RNA polymerase I (POLR1) transcripts, 18S and 28S rRNAs and their precursor, 45-47S pre-rRNA, but had no effect on the POLR3 transcribed 5S rRNA levels. To our knowledge, this is the first report of flavivirus-induced decrease of specifically POLR1 rRNA transcripts accompanied by host translational shut-off. Tick-borne encephalitis virus (TBEV) is a causative agent of a severe human neuroinfection that threatens Europe and Asia. Little is known about the interaction of this neurotropic virus with neural cells, even though this may be important to better understand why or how TBEV can cause high pathogenicity in humans, especially following neural cell infection. Here, we showed that TBEV induced host translational shut-off in cells of neural origin. In addition, TBEV interfered also with the expression of host ribosomal RNAs. Interestingly, the transcriptional shut-off was documented for rRNA species transcribed by RNA polymerase I (18S rRNA, 28S rRNA and their precursor 45-47S pre-rRNA), but not for RNA polymerase III rRNA transcripts (5S rRNA). Artificial inhibition of host translation using cycloheximide resulted in the decrease of all rRNA species. Based on these data, TBEV seems to specifically target transcription of RNA polymerase I. These new findings further increase our understanding of TBEV interactions with a key target cell type.
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Affiliation(s)
- Martin Selinger
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská, České Budějovice, Czech Republic
| | - Hana Tykalová
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská, České Budějovice, Czech Republic
| | - Ján Štěrba
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská, České Budějovice, Czech Republic
| | - Pavlína Věchtová
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská, České Budějovice, Czech Republic
| | - Zuzana Vavrušková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
| | - Jaroslava Lieskovská
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská, České Budějovice, Czech Republic
| | - Alain Kohl
- MRC-University of Glasgow Centre for Virus Research, Glasgow, Scotland, United Kingdom
| | - Esther Schnettler
- Bernhard-Nocht-Institute for Tropical Medicine, Bernhard-Nocht-Str. 74, Hamburg, Germany
- German Centre for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel-Riems, Hamburg, Germany
- * E-mail: (ES); (LG)
| | - Libor Grubhoffer
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia in České Budějovice, Branišovská, České Budějovice, Czech Republic
- * E-mail: (ES); (LG)
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Song Y, Liu Y, Wu P, Zhang F, Wang G. Genome-wide mRNA expression analysis of peripheral blood from patients with obsessive-compulsive disorder. Sci Rep 2018; 8:12583. [PMID: 30135499 PMCID: PMC6105577 DOI: 10.1038/s41598-018-30624-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 08/02/2018] [Indexed: 11/20/2022] Open
Abstract
The onset of obsessive-compulsive disorder (OCD) involves the interaction of heritability and environment. The aim of this study is to identify the global messenger RNA (mRNA) expressed in peripheral blood from 30 patients with OCD and 30 paired healthy controls. We generated whole-genome gene expression profiles of peripheral blood mononuclear cells (PBMCs) from all the subjects using microarrays. The expression of the top 10 mRNAs was verified by real-time quantitative PCR (qRT-PCR) analysis. We also performed an enrichment analysis of the gene ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) annotations of the differentially expressed mRNAs. We identified 51 mRNAs that were significantly differentially expressed between the subjects with OCD and the controls (fold change ≥1.5; false discovery rate <0.05); 45 mRNAs were down-regulated and 6 mRNAs were up-regulated. The qRT-PCR analysis of 10 selected genes showed that they were all up-regulated, which was opposite to the results obtained from the microarrays. The GO and KEGG enrichment analysis showed that ribosomal pathway was the most enriched pathway among the differentially expressed mRNAs. Our findings support the idea that altered genome expression profiles may underlie the development of OCD.
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Affiliation(s)
- Yuqing Song
- Peking University Sixth Hospital (Institute of Mental Health), Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Centre for Mental Disorders (Peking University Sixth Hospital), Beijing, 100191, China
| | - Yansong Liu
- Department of Clinical Psychology, Suzhou Psychiatric Hospital, The Affiliated Guangji Hospital of Soochow University, Suzhou, 215137, Jiangsu, China
| | - Panpan Wu
- Wuxi Mental Health Centre, Nanjing Medical University, Wuxi, 214151, Jiangsu, China
| | - Fuquan Zhang
- Wuxi Mental Health Centre, Nanjing Medical University, Wuxi, 214151, Jiangsu, China.
| | - Guoqiang Wang
- Wuxi Mental Health Centre, Nanjing Medical University, Wuxi, 214151, Jiangsu, China.
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Strand-Specific Dual RNA Sequencing of Bronchial Epithelial Cells Infected with Influenza A/H3N2 Viruses Reveals Splicing of Gene Segment 6 and Novel Host-Virus Interactions. J Virol 2018; 92:JVI.00518-18. [PMID: 29976658 DOI: 10.1128/jvi.00518-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/24/2018] [Indexed: 02/08/2023] Open
Abstract
Host-influenza virus interplay at the transcript level has been extensively characterized in epithelial cells. Yet, there are no studies that simultaneously characterize human host and influenza A virus (IAV) genomes. We infected human bronchial epithelial BEAS-2B cells with two seasonal IAV/H3N2 strains, Brisbane/10/07 and Perth/16/09 (reference strains for past vaccine seasons) and the well-characterized laboratory strain Udorn/307/72. Strand-specific RNA sequencing (RNA-seq) of the infected BEAS-2B cells allowed for simultaneous analysis of host and viral transcriptomes, in addition to pathogen genomes, to reveal changes in mRNA expression and alternative splicing (AS). In general, patterns of global and immune gene expression induced by the three IAVs were mostly shared. However, AS of host transcripts and small nuclear RNAs differed between the seasonal and laboratory strains. Analysis of viral transcriptomes showed deletions of the polymerase components (defective interfering-like RNAs) within the genome. Surprisingly, we found that the neuraminidase gene undergoes AS and that the splicing event differs between seasonal and laboratory strains. Our findings reveal novel elements of the host-virus interaction and highlight the importance of RNA-seq in identifying molecular changes at the genome level that may contribute to shaping RNA-based innate immunity.IMPORTANCE The use of massively parallel RNA sequencing (RNA-seq) has revealed insights into human and pathogen genomes and their evolution. Dual RNA-seq allows simultaneous dissection of host and pathogen genomes and strand-specific RNA-seq provides information about the polarity of the RNA. This is important in the case of negative-strand RNA viruses like influenza virus, which generate positive (complementary and mRNA) and negative-strand RNAs (genome) that differ in their potential to trigger innate immunity. Here, we characterize interactions between human bronchial epithelial cells and three influenza A/H3N2 strains using strand-specific dual RNA-seq. We focused on this subtype because of its epidemiological importance in causing significant morbidity and mortality during influenza epidemics. We report novel elements that differ between seasonal and laboratory strains highlighting the complexity of the host-virus interplay at the RNA level.
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Filippova JA, Semenov DV, Juravlev ES, Komissarov AB, Richter VA, Stepanov GA. Modern Approaches for Identification of Modified Nucleotides in RNA. BIOCHEMISTRY (MOSCOW) 2018; 82:1217-1233. [PMID: 29223150 DOI: 10.1134/s0006297917110013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This review considers approaches for detection of modified monomers in the RNA structure of living organisms. Recently, some data on dynamic alterations in the pool of modifications of the key RNA species that depend on external factors affecting the cells and physiological conditions of the whole organism have been accumulated. The recent studies have presented experimental data on relationship between the mechanisms of formation of modified/minor nucleotides of RNA in mammalian cells and the development of various pathologies. The development of novel methods for detection of chemical modifications of RNA nucleotides in the cells of living organisms and accumulation of knowledge on the contribution of modified monomers to metabolism and functioning of individual RNA species establish the basis for creation of novel diagnostic and therapeutic approaches. This review includes a short description of routine methods for determination of modified nucleotides in RNA and considers in detail modern approaches that enable not only detection but also quantitative assessment of the modification level of various nucleotides in individual RNA species.
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Affiliation(s)
- J A Filippova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, 630090, Russia.
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Waku T, Nakajima Y, Yokoyama W, Nomura N, Kako K, Kobayashi A, Shimizu T, Fukamizu A. NML-mediated rRNA base methylation links ribosomal subunit formation to cell proliferation in a p53-dependent manner. J Cell Sci 2016; 129:2382-93. [PMID: 27149924 DOI: 10.1242/jcs.183723] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 04/29/2016] [Indexed: 12/25/2022] Open
Abstract
Ribosomal RNAs (rRNAs) act as scaffolds and ribozymes in ribosomes, and these functions are modulated by post-transcriptional modifications. However, the biological role of base methylation, a well-conserved modification of rRNA, is poorly understood. Here, we demonstrate that a nucleolar factor, nucleomethylin (NML; also known as RRP8), is required for the N(1)-methyladenosine (m(1)A) modification in 28S rRNAs of human and mouse cells. NML also contributes to 60S ribosomal subunit formation. Intriguingly, NML depletion increases 60S ribosomal protein L11 (RPL11) levels in the ribosome-free fraction and protein levels of p53 through an RPL11-MDM2 complex, which activates the p53 pathway. Consequently, the growth of NML-depleted cells is suppressed in a p53-dependent manner. These observations reveal a new biological function of rRNA base methylation, which links ribosomal subunit formation to p53-dependent inhibition of cell proliferation in mammalian cells.
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Affiliation(s)
- Tsuyoshi Waku
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yuka Nakajima
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Wataru Yokoyama
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Naoto Nomura
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Koichiro Kako
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
| | - Akira Kobayashi
- Laboratory for Genetic Code, Graduate School of Life and Medical Sciences, Doshisha University, Kyotanabe, Kyoto 610-0394, Japan
| | - Toshiyuki Shimizu
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Akiyoshi Fukamizu
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
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10
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Ouellet Lavallée G, Pearson A. Upstream binding factor inhibits herpes simplex virus replication. Virology 2015; 483:108-16. [PMID: 25965800 DOI: 10.1016/j.virol.2015.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 01/09/2015] [Accepted: 04/02/2015] [Indexed: 12/16/2022]
Abstract
Herpes simplex virus 1 (HSV-1) infection induces changes to the host cell nucleus including relocalization of the cellular protein Upstream Binding Factor (UBF) from the nucleolus to viral replication compartments (VRCs). Herein, we tested the hypothesis that UBF is recruited to VRCs to promote viral DNA replication. Surprisingly, infection of UBF-depleted HeLa cells with HSV-1 or HSV-2 produced higher viral titers compared to controls. Reduced expression of UBF also led to a progressive increase in the relative amount of HSV-1 DNA versus controls, and increased levels of HSV-1 ICP27 and TK mRNA and protein, regardless of whether viral DNA replication was inhibited or not. Our results suggest that UBF can inhibit gene expression from viral DNA prior to its replication. A similar but smaller effect on viral titers was observed in human foreskin fibroblasts. This is the first report of UBF having a restrictive effect on replication of a virus.
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11
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Yan G, Yan X. Ribosomal proteomics: Strategies, approaches, and perspectives. Biochimie 2015; 113:69-77. [PMID: 25869001 DOI: 10.1016/j.biochi.2015.03.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 03/31/2015] [Indexed: 12/20/2022]
Abstract
Over the past few decades, proteomic research has seen unprecedented development due to technological advancement. However, whole-cell proteomics still has limitations with respect to sample complexity and the accuracy of determining protein locations. To deal with these limitations, several subcellular proteomic studies have been initiated. Nevertheless, compared to other subcellular proteomic fields, such as mitochondrial proteomics, ribosomal proteomics has lagged behind due to the long-held idea that the ribosome is just a translation machine. Recently, with the proposed ribosome filter hypothesis and subsequent studies of ribosome-specific regulatory capacity, ribosomal proteomics has become a promising chapter for both proteomic and ribosomal research. In this review, we discuss the current strategies and approaches in ribosomal proteomics and the efficacies as well as disadvantages of individual approaches for further improvement.
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Affiliation(s)
- Guokai Yan
- College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, Hubei, China
| | - Xianghua Yan
- College of Animal Sciences and Technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China; The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, Hubei, China.
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Kleinman CL, Doria M, Orecchini E, Giuliani E, Galardi S, De Jay N, Michienzi A. HIV-1 infection causes a down-regulation of genes involved in ribosome biogenesis. PLoS One 2014; 9:e113908. [PMID: 25462981 PMCID: PMC4252078 DOI: 10.1371/journal.pone.0113908] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/28/2014] [Indexed: 01/04/2023] Open
Abstract
HIV-1 preferentially infects CD4+ T cells, causing fundamental changes that eventually lead to the release of new viral particles and cell death. To investigate in detail alterations in the transcriptome of the CD4+ T cells upon viral infection, we sequenced polyadenylated RNA isolated from Jurkat cells infected or not with HIV-1. We found a marked global alteration of gene expression following infection, with an overall trend toward induction of genes, indicating widespread modification of the host biology. Annotation and pathway analysis of the most deregulated genes showed that viral infection produces a down-regulation of genes associated with the nucleolus, in particular those implicated in regulating the different steps of ribosome biogenesis, such as ribosomal RNA (rRNA) transcription, pre-rRNA processing, and ribosome maturation. The impact of HIV-1 infection on genes involved in ribosome biogenesis was further validated in primary CD4+ T cells. Moreover, we provided evidence by Northern Blot experiments, that host pre-rRNA processing in Jurkat cells might be perturbed during HIV-1 infection, thus strengthening the hypothesis of a crosstalk between nucleolar functions and viral pathogenesis.
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Affiliation(s)
- Claudia L. Kleinman
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital and Department of Human Genetics, McGill University, 3755 Côte Ste-Catherine Road, Montréal, Quebec, H3T 1E2, Canada
| | - Margherita Doria
- Laboratory of Immunoinfectivology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Elisa Orecchini
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Erica Giuliani
- Laboratory of Immunoinfectivology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Silvia Galardi
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
| | - Nicolas De Jay
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital and Department of Human Genetics, McGill University, 3755 Côte Ste-Catherine Road, Montréal, Quebec, H3T 1E2, Canada
| | - Alessandro Michienzi
- Department of Biomedicine and Prevention, University of Rome “Tor Vergata”, Rome, Italy
- * E-mail:
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13
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Salvetti A, Greco A. Viruses and the nucleolus: the fatal attraction. Biochim Biophys Acta Mol Basis Dis 2013; 1842:840-7. [PMID: 24378568 PMCID: PMC7135015 DOI: 10.1016/j.bbadis.2013.12.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/05/2013] [Accepted: 12/09/2013] [Indexed: 12/13/2022]
Abstract
Viruses are small obligatory parasites and as a consequence, they have developed sophisticated strategies to exploit the host cell's functions to create an environment that favors their own replication. A common feature of most – if not all – families of human and non-human viruses concerns their interaction with the nucleolus. The nucleolus is a multifunctional nuclear domain, which, in addition to its well-known role in ribosome biogenesis, plays several crucial other functions. Viral infection induces important nucleolar alterations. Indeed, during viral infection numerous viral components localize in nucleoli, while various host nucleolar proteins are redistributed in other cell compartments or are modified, and non-nucleolar cellular proteins reach the nucleolus. This review highlights the interactions reported between the nucleolus and some human or animal viral families able to establish a latent or productive infection, selected on the basis of their known interactions with the nucleolus and the nucleolar activities, and their links with virus replication and/or pathogenesis. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease. Most viruses interact with the nucleolus that plays a major role in virus life cycle. Virus/nucleolus interaction is crucial for virus replication and pathogenesis. Role of nucleoli in the infection with selected RNA viruses and herpes viruses
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Affiliation(s)
- Anna Salvetti
- Centre International de Recherche en Infectiologie (CIRI, International Center for Infectiology Research), Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 Allée d'Italie, 69365 Lyon CEDEX, France; LabEx Ecofect, Université de Lyon, 69007 Lyon, France.
| | - Anna Greco
- Centre International de Recherche en Infectiologie (CIRI, International Center for Infectiology Research), Inserm U1111, CNRS UMR5308, Ecole Normale Supérieure de Lyon, Université de Lyon, 46 Allée d'Italie, 69365 Lyon CEDEX, France; LabEx Ecofect, Université de Lyon, 69007 Lyon, France.
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14
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Marcel V, Ghayad S, Belin S, Therizols G, Morel AP, Solano-Gonzàlez E, Vendrell J, Hacot S, Mertani H, Albaret M, Bourdon JC, Jordan L, Thompson A, Tafer Y, Cong R, Bouvet P, Saurin JC, Catez F, Prats AC, Puisieux A, Diaz JJ. p53 acts as a safeguard of translational control by regulating fibrillarin and rRNA methylation in cancer. Cancer Cell 2013; 24:318-30. [PMID: 24029231 PMCID: PMC7106277 DOI: 10.1016/j.ccr.2013.08.013] [Citation(s) in RCA: 217] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/08/2013] [Accepted: 08/12/2013] [Indexed: 01/01/2023]
Abstract
Ribosomes are specialized entities that participate in regulation of gene expression through their rRNAs carrying ribozyme activity. Ribosome biogenesis is overactivated in p53-inactivated cancer cells, although involvement of p53 on ribosome quality is unknown. Here, we show that p53 represses expression of the rRNA methyl-transferase fibrillarin (FBL) by binding directly to FBL. High levels of FBL are accompanied by modifications of the rRNA methylation pattern, impairment of translational fidelity, and an increase of internal ribosome entry site (IRES)-dependent translation initiation of key cancer genes. FBL overexpression contributes to tumorigenesis and is associated with poor survival in patients with breast cancer. Thus, p53 acts as a safeguard of protein synthesis by regulating FBL and the subsequent quality and intrinsic activity of ribosomes.
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Affiliation(s)
- Virginie Marcel
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Sandra E. Ghayad
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Stéphane Belin
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Gabriel Therizols
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Anne-Pierre Morel
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Eduardo Solano-Gonzàlez
- Université de Toulouse, UPS, TRADGENE, EA4554, Institut des Maladies Métaboliques et Cardiovasculaires, 1 Avenue Jean Poulhès, BP 84225, F-31432 Toulouse, France
| | - Julie A. Vendrell
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
- ISPB, Faculté de Pharmacie, Université Lyon 1, Lyon, France
- Dundee Cancer Centre, Clinical Research Centre, University of Dundee, Dundee DD1 9SY, UK
| | - Sabine Hacot
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Hichem C. Mertani
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Marie Alexandra Albaret
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | | | - Lee Jordan
- Department of Pathology, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK
| | - Alastair Thompson
- Dundee Cancer Centre, Clinical Research Centre, University of Dundee, Dundee DD1 9SY, UK
| | - Yasmine Tafer
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Rong Cong
- Laboratoire Joliot-Curie, Ecole Normale Supérieure de Lyon, Université de Lyon, CNRS USR 3010, SFR BioSciences UMS3444, Lyon 69364, France
| | - Philippe Bouvet
- Laboratoire Joliot-Curie, Ecole Normale Supérieure de Lyon, Université de Lyon, CNRS USR 3010, SFR BioSciences UMS3444, Lyon 69364, France
| | - Jean-Christophe Saurin
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
- Gastroenterology Unit, Édouard Herriot Hospital, Hospices Civils de Lyon, 69002 Lyon, France
| | - Frédéric Catez
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Anne-Catherine Prats
- Université de Toulouse, UPS, TRADGENE, EA4554, Institut des Maladies Métaboliques et Cardiovasculaires, 1 Avenue Jean Poulhès, BP 84225, F-31432 Toulouse, France
| | - Alain Puisieux
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
| | - Jean-Jacques Diaz
- Centre de Recherche en Cancérologie de Lyon UMR Inserm 1052 CNRS 5286, Centre Léon Bérard, F-69373, Lyon, France
- Université de Lyon, Université Lyon 1, ISPB, Lyon F-69622, France
- Corresponding author
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15
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Greco A, Arata L, Soler E, Gaume X, Couté Y, Hacot S, Callé A, Monier K, Epstein AL, Sanchez JC, Bouvet P, Diaz JJ. Nucleolin interacts with US11 protein of herpes simplex virus 1 and is involved in its trafficking. J Virol 2012; 86:1449-57. [PMID: 22130536 PMCID: PMC3264372 DOI: 10.1128/jvi.06194-11] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 11/18/2011] [Indexed: 02/06/2023] Open
Abstract
Herpes simplex virus type 1 (HSV-1) infection induces profound nucleolar modifications at the functional and organizational levels, including nucleolar invasion by several viral proteins. One of these proteins is US11, which exhibits several different functions and displays both cytoplasmic localization and clear nucleolar localization very similar to that of the major multifunctional nucleolar protein nucleolin. To determine whether US11 interacts with nucleolin, we purified US11 protein partners by coimmunoprecipitations using a tagged protein, Flag-US11. From extracts of cells expressing Flag-US11 protein, we copurified a protein of about 100 kDa that was further identified as nucleolin. In vitro studies have demonstrated that nucleolin interacts with US11 and that the C-terminal domain of US11, which is required for US11 nucleolar accumulation, is sufficient for interaction with nucleolin. This association was confirmed in HSV-1-infected cells. We found an increase in the nucleolar accumulation of US11 in nucleolin-depleted cells, thereby revealing that nucleolin could play a role in US11 nucleocytoplasmic trafficking through one-way directional transport out of the nucleolus. Since nucleolin is required for HSV-1 nuclear egress, the interaction of US11 with nucleolin may participate in the outcome of infection.
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Affiliation(s)
- Anna Greco
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
| | - Loredana Arata
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
| | - Eric Soler
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
| | - Xavier Gaume
- Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS USR 3010, Laboratoire Joliot-Curie, Lyon, France
| | - Yohann Couté
- Geneva Proteomics Center, Central Clinical Chemistry Laboratory, Geneva University Hospital, Genève, Switzerland
| | - Sabine Hacot
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
- CRCL Inserm U1052, CNRS UMR 5286, Centre Léon Bérard, Lyon, France
| | - Aleth Callé
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
| | - Karine Monier
- Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS USR 3010, Laboratoire Joliot-Curie, Lyon, France
| | - Alberto L. Epstein
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
| | - Jean-Charles Sanchez
- Human Protein Sciences, Faculty of Medicine, Geneva University, Geneva, Switzerland
| | - Philippe Bouvet
- Université de Lyon, Ecole Normale Supérieure de Lyon, CNRS USR 3010, Laboratoire Joliot-Curie, Lyon, France
| | - Jean-Jacques Diaz
- Université de Lyon and Université Lyon 1, Lyon, France, and CNRS, UMR5534, Centre de Génétique et de Physiologie Moléculaire et Cellulaire, Villeurbanne, France
- CRCL Inserm U1052, CNRS UMR 5286, Centre Léon Bérard, Lyon, France
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16
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Belin S, Hacot S, Daudignon L, Therizols G, Pourpe S, Mertani HC, Rosa-Calatrava M, Diaz JJ. Purification of ribosomes from human cell lines. ACTA ACUST UNITED AC 2011; Chapter 3:Unit 3.40. [PMID: 21154551 DOI: 10.1002/0471143030.cb0340s49] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Highly conserved during evolution, the ribosome is the central effector of protein synthesis. In mammalian cells, the ribosome is a macromolecular complex composed of four different ribosomal RNAs (rRNA) and about 80 ribosomal proteins. Requiring more than 200 factors, ribosome biogenesis is a highly complex process that takes place mainly within the nucleoli of eukaryotic cells. Crystallographic data suggest that the ribosome is a ribozyme, in which the rRNA catalyses the peptide bond formation and ensures quality control of the translation. Ribosomal proteins are involved in this molecular mechanism; nonetheless, their role is still not fully characterized. Recent studies suggest that ribosomes themselves and/or the mechanisms underlying their synthesis, processing, and assembly play a key role in the establishment and progression of several human pathologies. The protocol described here is simple, efficient, and robust, and allows one to purify high-quality ribosomes from human cultured cell lines. Ribosomes purified with this protocol are adequate for most of the subsequent analyses of their RNA and protein content.
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17
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Lymberopoulos MH, Bourget A, Ben Abdeljelil N, Pearson A. Involvement of the UL24 protein in herpes simplex virus 1-induced dispersal of B23 and in nuclear egress. Virology 2011; 412:341-8. [PMID: 21316727 DOI: 10.1016/j.virol.2011.01.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Revised: 11/10/2010] [Accepted: 01/17/2011] [Indexed: 10/18/2022]
Abstract
UL24 of herpes simplex virus 1 (HSV-1) is widely conserved within the Herpesviridae family. Herein, we tested the hypothesis that UL24, which we have previously shown to induce the redistribution of nucleolin, also affects the localization of the nucleolar protein B23. We found that HSV-1-induced dispersal of B23 was dependent on UL24. The conserved N-terminal portion of UL24 was sufficient to induce the redistribution of B23 in transient transfection assays. Mutational analysis revealed that the endonuclease motif of UL24 was important for B23 dispersal in both transfected and infected cells. Nucleolar protein relocalization during HSV-1 infection was also observed in non-immortalized cells. Analysis of infected cells by electron microscopy revealed a decrease in the ratio of cytoplasmic versus nuclear viral particles in cells infected with a UL24-deficient strain compared to KOS-infected cells. Our results suggest that UL24 promotes nuclear egress of nucleocapsids during HSV-1 infection, possibly though effects on nucleoli.
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Affiliation(s)
- Maria H Lymberopoulos
- INRS-Institut Armand-Frappier, Université du Québec, 531 boul. des Prairies, Laval, Québec H7V 1B7, Canada
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18
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Boulon S, Westman BJ, Hutten S, Boisvert FM, Lamond AI. The nucleolus under stress. Mol Cell 2010; 40:216-27. [PMID: 20965417 PMCID: PMC2987465 DOI: 10.1016/j.molcel.2010.09.024] [Citation(s) in RCA: 764] [Impact Index Per Article: 54.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 08/16/2010] [Accepted: 09/22/2010] [Indexed: 12/16/2022]
Abstract
Cells typically respond quickly to stress, altering their metabolism to compensate. In mammalian cells, stress signaling usually leads to either cell-cycle arrest or apoptosis, depending on the severity of the insult and the ability of the cell to recover. Stress also often leads to reorganization of nuclear architecture, reflecting the simultaneous inhibition of major nuclear pathways (e.g., replication and transcription) and activation of specific stress responses (e.g., DNA repair). In this review, we focus on how two nuclear organelles, the nucleolus and the Cajal body, respond to stress. The nucleolus senses stress and is a central hub for coordinating the stress response. We review nucleolar function in the stress-induced regulation of p53 and the specific changes in nucleolar morphology and composition that occur upon stress. Crosstalk between nucleoli and CBs is also discussed in the context of stress responses.
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Affiliation(s)
- Séverine Boulon
- Wellcome Trust Centre for Gene Regulation and Expression, University of Dundee, Dundee DD1 5EH, UK
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