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Levintov L, Vashisth H. Structural and computational studies of HIV-1 RNA. RNA Biol 2024; 21:1-32. [PMID: 38100535 PMCID: PMC10730233 DOI: 10.1080/15476286.2023.2289709] [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] [Accepted: 11/21/2023] [Indexed: 12/17/2023] Open
Abstract
Viruses remain a global threat to animals, plants, and humans. The type 1 human immunodeficiency virus (HIV-1) is a member of the retrovirus family and carries an RNA genome, which is reverse transcribed into viral DNA and further integrated into the host-cell DNA for viral replication and proliferation. The RNA structures from the HIV-1 genome provide valuable insights into the mechanisms underlying the viral replication cycle. Moreover, these structures serve as models for designing novel therapeutic approaches. Here, we review structural data on RNA from the HIV-1 genome as well as computational studies based on these structural data. The review is organized according to the type of structured RNA element which contributes to different steps in the viral replication cycle. This is followed by an overview of the HIV-1 transactivation response element (TAR) RNA as a model system for understanding dynamics and interactions in the viral RNA systems. The review concludes with a description of computational studies, highlighting the impact of biomolecular simulations in elucidating the mechanistic details of various steps in the HIV-1's replication cycle.
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Affiliation(s)
- Lev Levintov
- Department of Chemical Engineering & Bioengineering, University of New Hampshire, Durham, USA
| | - Harish Vashisth
- Department of Chemical Engineering & Bioengineering, University of New Hampshire, Durham, USA
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2
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Shirokikh NE, Jensen KB, Thakor N. Editorial: RNA machines. Front Genet 2023; 14:1290420. [PMID: 37829284 PMCID: PMC10565666 DOI: 10.3389/fgene.2023.1290420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 09/18/2023] [Indexed: 10/14/2023] Open
Affiliation(s)
- Nikolay E. Shirokikh
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Kirk Blomquist Jensen
- School of Biological Sciences, Faculty of Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Nehal Thakor
- Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, AB, Canada
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3
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Liang T, Li G, Lu Y, Hu M, Ma X. The Involvement of Ubiquitination and SUMOylation in Retroviruses Infection and Latency. Viruses 2023; 15:v15040985. [PMID: 37112965 PMCID: PMC10144533 DOI: 10.3390/v15040985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/15/2023] [Accepted: 04/16/2023] [Indexed: 04/29/2023] Open
Abstract
Retroviruses, especially the pathogenic human immunodeficiency virus type 1 (HIV-1), have severely threatened human health for decades. Retroviruses can form stable latent reservoirs via retroviral DNA integration into the host genome, and then be temporarily transcriptional silencing in infected cells, which makes retroviral infection incurable. Although many cellular restriction factors interfere with various steps of the life cycle of retroviruses and the formation of viral latency, viruses can utilize viral proteins or hijack cellular factors to evade intracellular immunity. Many post-translational modifications play key roles in the cross-talking between the cellular and viral proteins, which has greatly determined the fate of retroviral infection. Here, we reviewed recent advances in the regulation of ubiquitination and SUMOylation in the infection and latency of retroviruses, focusing on both host defense- and virus counterattack-related ubiquitination and SUMOylation system. We also summarized the development of ubiquitination- and SUMOylation-targeted anti-retroviral drugs and discussed their therapeutic potential. Manipulating ubiquitination or SUMOylation pathways by targeted drugs could be a promising strategy to achieve a "sterilizing cure" or "functional cure" of retroviral infection.
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Affiliation(s)
- Taizhen Liang
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Guojie Li
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Yunfei Lu
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Meilin Hu
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
| | - Xiancai Ma
- State Key Laboratory of Respiratory Disease, Guangzhou Medical University, Guangzhou 511400, China
- Guangzhou Laboratory, Guangzhou International Bio-Island, Guangzhou 510005, China
- Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China
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4
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Nakano K, Watanabe T. Tuning Rex rules HTLV-1 pathogenesis. Front Immunol 2022; 13:959962. [PMID: 36189216 PMCID: PMC9523361 DOI: 10.3389/fimmu.2022.959962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 08/29/2022] [Indexed: 12/02/2022] Open
Abstract
HTLV-1 is an oncovirus causing ATL and other inflammatory diseases such as HAM/TSP and HU in about 5% of infected individuals. It is also known that HTLV-1-infected cells maintain a disease-free, immortalized, latent state throughout the lifetimes of about 95% of infected individuals. We believe that the stable maintenance of disease-free infected cells in the carrier is an intrinsic characteristic of HTLV-1 that has been acquired during its evolution in the human life cycle. We speculate that the pathogenesis of the virus is ruled by the orchestrated functions of viral proteins. In particular, the regulation of Rex, the conductor of viral replication rate, is expected to be closely related to the viral program in the early active viral replication followed by the stable latency in HTLV-1 infected T cells. HTLV-1 and HIV-1 belong to the family Retroviridae and share the same tropism, e.g., human CD4+ T cells. These viruses show significant similarities in the viral genomic structure and the molecular mechanism of the replication cycle. However, HTLV-1 and HIV-1 infected T cells show different phenotypes, especially in the level of virion production. We speculate that how the activity of HTLV-1 Rex and its counterpart HIV-1 Rev are regulated may be closely related to the properties of respective infected T cells. In this review, we compare various pathological aspects of HTLV-1 and HIV-1. In particular, we investigated the presence or absence of a virally encoded “regulatory valve” for HTLV-1 Rex or HIV-1 Rev to explore its importance in the regulation of viral particle production in infected T cells. Finally, wereaffirm Rex as the key conductor for viral replication and viral pathogenesis based on our recent study on the novel functional aspects of Rex. Since the activity of Rex is closely related to the viral replication rate, we hypothesize that the “regulatory valve” on the Rex activity may have been selectively evolved to achieve the “scenario” with early viral particle production and the subsequent long, stable deep latency in HTLV-1 infected cells.
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Affiliation(s)
- Kazumi Nakano
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
- *Correspondence: Kazumi Nakano,
| | - Toshiki Watanabe
- Department of Practical Management of Medical Information, Graduate School of Medicine, St. Marianna University, Kawasaki, Japan
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5
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Viral and Host Factors Regulating HIV-1 Envelope Protein Trafficking and Particle Incorporation. Viruses 2022; 14:v14081729. [PMID: 36016351 PMCID: PMC9415270 DOI: 10.3390/v14081729] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/25/2022] [Accepted: 08/02/2022] [Indexed: 11/17/2022] Open
Abstract
The HIV-1 envelope glycoprotein (Env) is an essential structural component of the virus, serving as the receptor-binding protein and principal neutralizing determinant. Env trimers are incorporated into developing particles at the plasma membrane of infected cells. Incorporation of HIV-1 Env into particles in T cells and macrophages is regulated by the long Env cytoplasmic tail (CT) and the matrix region of Gag. The CT incorporates motifs that interact with cellular factors involved in endosomal trafficking. Env follows an unusual pathway to arrive at the site of particle assembly, first traversing the secretory pathway to the plasma membrane (PM), then undergoing endocytosis, followed by directed sorting to the site of particle assembly on the PM. Many aspects of Env trafficking remain to be defined, including the sequential events that occur following endocytosis, leading to productive recycling and particle incorporation. This review focuses on the host factors and pathways involved in Env trafficking, and discusses leading models of Env incorporation into particles.
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6
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Gallardo CM, Nguyen AVT, Routh AL, Torbett BE. Selective ablation of 3' RNA ends and processive RTs facilitate direct cDNA sequencing of full-length host cell and viral transcripts. Nucleic Acids Res 2022; 50:e98. [PMID: 35736235 PMCID: PMC9508845 DOI: 10.1093/nar/gkac516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/25/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Alternative splicing (AS) is necessary for viral proliferation in host cells and a critical regulatory component of viral gene expression. Conventional RNA-seq approaches provide incomplete coverage of AS due to their short read lengths and are susceptible to biases and artifacts introduced in prevailing library preparation methodologies. Moreover, viral splicing studies are often conducted separately from host cell transcriptome analysis, precluding an assessment of the viral manipulation of host splicing machinery. To address current limitations, we developed a quantitative full-length direct cDNA sequencing strategy to simultaneously profile viral and host cell transcripts. This nanopore-based approach couples processive reverse transcriptases with a novel one-step chemical ablation of 3' RNA ends (termed CASPR), which decreases ribosomal RNA reads and enriches polyadenylated coding sequences. We extensively validate our approach using synthetic reference transcripts and show that CASPR doubles the breadth of coverage per transcript and increases detection of long transcripts (>4 kb), while being functionally equivalent to PolyA+ selection for transcript quantification. We used our approach to interrogate host cell and HIV-1 transcript dynamics during viral reactivation and identified novel putative HIV-1 host factors containing exon skipping or novel intron retentions and delineated the HIV-1 transcriptional state associated with these differentially regulated host factors.
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Affiliation(s)
- Christian M Gallardo
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA.,Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Anh-Viet T Nguyen
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Andrew L Routh
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Bruce E Torbett
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA.,Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, WA 98101, USA.,Institute for Stem Cell & Regenerative Medicine, University of Washington, Seattle, WA 98109, USA.,Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA 98101, USA.,Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98101, USA
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7
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Crespo R, Rao S, Mahmoudi T. HibeRNAtion: HIV-1 RNA Metabolism and Viral Latency. Front Cell Infect Microbiol 2022; 12:855092. [PMID: 35774399 PMCID: PMC9237370 DOI: 10.3389/fcimb.2022.855092] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 05/10/2022] [Indexed: 01/12/2023] Open
Abstract
HIV-1 infection remains non-curative due to the latent reservoir, primarily a small pool of resting memory CD4+ T cells bearing replication-competent provirus. Pharmacological reversal of HIV-1 latency followed by intrinsic or extrinsic cell killing has been proposed as a promising strategy to target and eliminate HIV-1 viral reservoirs. Latency reversing agents have been extensively studied for their role in reactivating HIV-1 transcription in vivo, although no permanent reduction of the viral reservoir has been observed thus far. This is partly due to the complex nature of latency, which involves strict intrinsic regulation at multiple levels at transcription and RNA processing. Still, the molecular mechanisms that control HIV-1 latency establishment and maintenance have been almost exclusively studied in the context of chromatin remodeling, transcription initiation and elongation and most known LRAs target LTR-driven transcription by manipulating these. RNA metabolism is a largely understudies but critical mechanistic step in HIV-1 gene expression and latency. In this review we provide an update on current knowledge on the role of RNA processing mechanisms in viral gene expression and latency and speculate on the possible manipulation of these pathways as a therapeutic target for future cure studies.
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Affiliation(s)
- Raquel Crespo
- Department of Biochemistry, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Shringar Rao
- Department of Biochemistry, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Tokameh Mahmoudi
- Department of Biochemistry, Erasmus University Medical Center, Rotterdam, Netherlands
- Department of Pathology, Erasmus University Medical Center, Rotterdam, Netherlands
- Department of Urology, Erasmus University Medical Center, Rotterdam, Netherlands
- *Correspondence: Tokameh Mahmoudi,
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8
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Gallo GL, López N, Loureiro ME. The Virus–Host Interplay in Junín Mammarenavirus Infection. Viruses 2022; 14:v14061134. [PMID: 35746604 PMCID: PMC9228484 DOI: 10.3390/v14061134] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 02/06/2023] Open
Abstract
Junín virus (JUNV) belongs to the Arenaviridae family and is the causative agent of Argentine hemorrhagic fever (AHF), a severe human disease endemic to agricultural areas in Argentina. At this moment, there are no effective antiviral therapeutics to battle pathogenic arenaviruses. Cumulative reports from recent years have widely provided information on cellular factors playing key roles during JUNV infection. In this review, we summarize research on host molecular determinants that intervene in the different stages of the viral life cycle: viral entry, replication, assembly and budding. Alongside, we describe JUNV tight interplay with the innate immune system. We also review the development of different reverse genetics systems and their use as tools to study JUNV biology and its close teamwork with the host. Elucidating relevant interactions of the virus with the host cell machinery is highly necessary to better understand the mechanistic basis beyond virus multiplication, disease pathogenesis and viral subversion of the immune response. Altogether, this knowledge becomes essential for identifying potential targets for the rational design of novel antiviral treatments to combat JUNV as well as other pathogenic arenaviruses.
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9
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McFadden WM, Snyder AA, Kirby KA, Tedbury PR, Raj M, Wang Z, Sarafianos SG. Rotten to the core: antivirals targeting the HIV-1 capsid core. Retrovirology 2021; 18:41. [PMID: 34937567 PMCID: PMC8693499 DOI: 10.1186/s12977-021-00583-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 11/09/2021] [Indexed: 12/20/2022] Open
Abstract
The capsid core of HIV-1 is a large macromolecular assembly that surrounds the viral genome and is an essential component of the infectious virus. In addition to its multiple roles throughout the viral life cycle, the capsid interacts with multiple host factors. Owing to its indispensable nature, the HIV-1 capsid has been the target of numerous antiretrovirals, though most capsid-targeting molecules have not had clinical success until recently. Lenacapavir, a long-acting drug that targets the HIV-1 capsid, is currently undergoing phase 2/3 clinical trials, making it the most successful capsid inhibitor to-date. In this review, we detail the role of the HIV-1 capsid protein in the virus life cycle, categorize antiviral compounds based on their targeting of five sites within the HIV-1 capsid, and discuss their molecular interactions and mechanisms of action. The diverse range of inhibition mechanisms provides insight into possible new strategies for designing novel HIV-1 drugs and furthers our understanding of HIV-1 biology. ![]()
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Affiliation(s)
- William M McFadden
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Alexa A Snyder
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Karen A Kirby
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA.,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Philip R Tedbury
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA.,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA
| | - Monika Raj
- Department of Chemistry, Emory University, Atlanta, GA, 30322, USA
| | - Zhengqiang Wang
- Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Stefan G Sarafianos
- Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, 30322, USA. .,Children's Healthcare of Atlanta, Atlanta, GA, 30322, USA.
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10
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Hadpech S, Moonmuang S, Chupradit K, Yasamut U, Tayapiwatana C. Updating on Roles of HIV Intrinsic Factors: A Review of Their Antiviral Mechanisms and Emerging Functions. Intervirology 2021; 65:67-79. [PMID: 34464956 DOI: 10.1159/000519241] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 08/24/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Host restriction factors are cellular proteins that inhibit specific steps of the viral life cycle. Since the 1970s, several new factors have been identified, including human immunodeficiency virus-1 (HIV-1) replication restriction. Evidence accumulated in the last decade has substantially broadened our understanding of the molecular mechanisms utilized to abrogate the HIV-1 life cycle. SUMMARY In this review, we focus on the interaction between host restriction factors participating in the early phase of HIV-1 infection, particularly CA-targeting proteins. Host factors involved in the late phase of the replication cycle, such as viral assembly and egress factors, are also described. Additionally, current reports on well-known antiviral intrinsic factors, as well as other viral restriction factors with their emerging roles, are included. CONCLUSION A comprehensive understanding of the interactions between viruses and hosts is expected to provide insight into the design of novel HIV-1 therapeutic interventions.
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Affiliation(s)
- Sudarat Hadpech
- Division of Pharmacology and Biopharmacy, Faculty of Pharmaceutical Sciences, Burapha University, Chon Buri, Thailand
| | - Sutpirat Moonmuang
- Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Center of Biomolecular Therapy and Diagnostic, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Koollawat Chupradit
- Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Center of Biomolecular Therapy and Diagnostic, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Siriraj Center for Regenerative Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Umpa Yasamut
- Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Center of Biomolecular Therapy and Diagnostic, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Center of Innovative Immunodiagnostic Development, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Chatchai Tayapiwatana
- Division of Clinical Immunology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Center of Biomolecular Therapy and Diagnostic, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.,Center of Innovative Immunodiagnostic Development, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
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11
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Hantak MP, Einstein J, Kearns RB, Shepherd JD. Intercellular Communication in the Nervous System Goes Viral. Trends Neurosci 2021; 44:248-259. [PMID: 33485691 PMCID: PMC8041237 DOI: 10.1016/j.tins.2020.12.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/19/2020] [Accepted: 12/30/2020] [Indexed: 12/20/2022]
Abstract
Viruses and transposable elements are major drivers of evolution and make up over half the sequences in the human genome. In some cases, these elements are co-opted to perform biological functions for the host. Recent studies made the surprising observation that the neuronal gene Arc forms virus-like protein capsids that can transfer RNA between neurons to mediate a novel intercellular communication pathway. Phylogenetic analyses showed that mammalian Arc is derived from an ancient retrotransposon of the Ty3/gypsy family and contains homology to the retroviral Gag polyproteins. The Drosophila Arc homologs, which are independently derived from the same family of retrotransposons, also mediate cell-to-cell signaling of RNA at the neuromuscular junction; a striking example of convergent evolution. Here we propose an Arc 'life cycle', based on what is known about retroviral Gag, and discuss how elucidating these biological processes may lead to novel insights into brain plasticity and memory.
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Affiliation(s)
- Michael P Hantak
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA
| | - Jenifer Einstein
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA
| | - Rachel B Kearns
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA
| | - Jason D Shepherd
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT, USA.
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12
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Ramdas P, Sahu AK, Mishra T, Bhardwaj V, Chande A. From Entry to Egress: Strategic Exploitation of the Cellular Processes by HIV-1. Front Microbiol 2020; 11:559792. [PMID: 33343516 PMCID: PMC7746852 DOI: 10.3389/fmicb.2020.559792] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 11/05/2020] [Indexed: 01/23/2023] Open
Abstract
HIV-1 employs a rich arsenal of viral factors throughout its life cycle and co-opts intracellular trafficking pathways. This exquisitely coordinated process requires precise manipulation of the host microenvironment, most often within defined subcellular compartments. The virus capitalizes on the host by modulating cell-surface proteins and cleverly exploiting nuclear import pathways for post entry events, among other key processes. Successful virus–cell interactions are indeed crucial in determining the extent of infection. By evolving defenses against host restriction factors, while simultaneously exploiting host dependency factors, the life cycle of HIV-1 presents a fascinating montage of an ongoing host–virus arms race. Herein, we provide an overview of how HIV-1 exploits native functions of the host cell and discuss recent findings that fundamentally change our understanding of the post-entry replication events.
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Affiliation(s)
- Pavitra Ramdas
- Molecular Virology Laboratory, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| | - Amit Kumar Sahu
- Molecular Virology Laboratory, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| | - Tarun Mishra
- Molecular Virology Laboratory, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| | - Vipin Bhardwaj
- Molecular Virology Laboratory, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
| | - Ajit Chande
- Molecular Virology Laboratory, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India
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13
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Advances in Continuous Microfluidics-Based Technologies for the Study of HIV Infection. Viruses 2020; 12:v12090982. [PMID: 32899657 PMCID: PMC7552050 DOI: 10.3390/v12090982] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/28/2020] [Accepted: 09/02/2020] [Indexed: 12/31/2022] Open
Abstract
HIV-1 is the causative agent of acquired immunodeficiency syndrome (AIDS). It affects millions of people worldwide and the pandemic persists despite the implementation of highly active antiretroviral therapy. A wide spectrum of techniques has been implemented in order to diagnose and monitor AIDS progression over the years. Besides the conventional approaches, microfluidics has provided useful methods for monitoring HIV-1 infection. In this review, we introduce continuous microfluidics as well as the fabrication and handling of microfluidic chips. We provide a review of the different applications of continuous microfluidics in AIDS diagnosis and progression and in the basic study of the HIV-1 life cycle.
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14
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Pinto DO, DeMarino C, Vo TT, Cowen M, Kim Y, Pleet ML, Barclay RA, Noren Hooten N, Evans MK, Heredia A, Batrakova EV, Iordanskiy S, Kashanchi F. Low-Level Ionizing Radiation Induces Selective Killing of HIV-1-Infected Cells with Reversal of Cytokine Induction Using mTOR Inhibitors. Viruses 2020; 12:E885. [PMID: 32823598 PMCID: PMC7472203 DOI: 10.3390/v12080885] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/07/2020] [Accepted: 08/10/2020] [Indexed: 12/12/2022] Open
Abstract
HIV-1 infects 39.5 million people worldwide, and cART is effective in preventing viral spread by reducing HIV-1 plasma viral loads to undetectable levels. However, viral reservoirs persist by mechanisms, including the inhibition of autophagy by HIV-1 proteins (i.e., Nef and Tat). HIV-1 reservoirs can be targeted by the "shock and kill" strategy, which utilizes latency-reversing agents (LRAs) to activate latent proviruses and immunotarget the virus-producing cells. Yet, limitations include reduced LRA permeability across anatomical barriers and immune hyper-activation. Ionizing radiation (IR) induces effective viral activation across anatomical barriers. Like other LRAs, IR may cause inflammation and modulate the secretion of extracellular vesicles (EVs). We and others have shown that cells may secrete cytokines and viral proteins in EVs and, therefore, LRAs may contribute to inflammatory EVs. In the present study, we mitigated the effects of IR-induced inflammatory EVs (i.e., TNF-α), through the use of mTOR inhibitors (mTORi; Rapamycin and INK128). Further, mTORi were found to enhance the selective killing of HIV-1-infected myeloid and T-cell reservoirs at the exclusion of uninfected cells, potentially via inhibition of viral transcription/translation and induction of autophagy. Collectively, the proposed regimen using cART, IR, and mTORi presents a novel approach allowing for the targeting of viral reservoirs, prevention of immune hyper-activation, and selectively killing latently infected HIV-1 cells.
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Affiliation(s)
- Daniel O. Pinto
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Catherine DeMarino
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Thy T. Vo
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Maria Cowen
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Yuriy Kim
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Michelle L. Pleet
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Robert A. Barclay
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
| | - Nicole Noren Hooten
- Laboratory of Epidemiology and Population Science, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (N.N.H.); (M.K.E.)
| | - Michele K. Evans
- Laboratory of Epidemiology and Population Science, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA; (N.N.H.); (M.K.E.)
| | - Alonso Heredia
- Institute of Human Virology, University of Maryland School of Medicine, University of Maryland, Baltimore, MD 21201, USA;
| | - Elena V. Batrakova
- Department of Medicine, University of North Carolina HIV Cure Center; University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC 27599, USA;
| | - Sergey Iordanskiy
- Department of Pharmacology and Molecular Therapeutics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA;
| | - Fatah Kashanchi
- Laboratory of Molecular Virology, School of Systems Biology, George Mason University, Manassas, VA 20110, USA; (D.O.P.); (C.D.); (T.T.V.); (M.C.); (Y.K.); (M.L.P.); (R.A.B.)
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15
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Barrera A, Olguín V, Vera-Otarola J, López-Lastra M. Cap-independent translation initiation of the unspliced RNA of retroviruses. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194583. [PMID: 32450258 DOI: 10.1016/j.bbagrm.2020.194583] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/12/2020] [Accepted: 05/18/2020] [Indexed: 12/12/2022]
Abstract
Retroviruses are a unique family of RNA viruses that utilize a virally encoded reverse transcriptase (RT) to replicate their genomic RNA (gRNA) through a proviral DNA intermediate. The provirus is permanently integrated into the host cell chromosome and is expressed by the host cell transcription, RNA processing, and translation machinery. Retroviral messenger RNAs (mRNAs) entirely resemble a cellular mRNA as they have a 5'cap structure, 5'untranslated region (UTR), an open reading frame (ORF), 3'UTR, and a 3'poly(A) tail. The primary transcription product interacts with the cellular RNA processing machinery and is spliced, exported to the cytoplasm, and translated. However, a proportion of the pre-mRNA subverts typical RNA processing giving rise to the full-length RNA. In the cytoplasm, the full-length retroviral RNA fulfills a dual role acting as mRNA and as the gRNA. Simple retroviruses generate two pools of full-length RNA, one for each purpose. However, complex retroviruses have a single pool of full-length RNA, which is destined for translation or encapsidation. As for eukaryotic mRNAs, translational control of retroviral protein synthesis is mostly exerted at the step of initiation. Interestingly, some retroviral mRNAs, both simple and complex, use a dual mechanism to initiate protein synthesis, a cap-dependent initiation mechanism, or via internal initiation using an internal ribosome entry site (IRES). In this review, we describe and discuss data regarding the molecular mechanism driving the canonical cap-dependent and IRES-mediated translation initiation for retroviral mRNA, focusing the discussion mainly on the most studied retroviral mRNA, the HIV-1 mRNA.
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Affiliation(s)
- Aldo Barrera
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Centro de Investigaciones Médicas, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile
| | - Valeria Olguín
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Centro de Investigaciones Médicas, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile
| | - Jorge Vera-Otarola
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Centro de Investigaciones Médicas, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile
| | - Marcelo López-Lastra
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Centro de Investigaciones Médicas, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Marcoleta 391, Santiago, Chile.
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16
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Ishaq M, Marshall H, Natarajan V. GADD34 attenuates HIV-1 replication by viral 5'-UTR TAR RNA-mediated translational inhibition. Virology 2020; 540:119-131. [PMID: 31778897 PMCID: PMC6957764 DOI: 10.1016/j.virol.2019.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 11/07/2019] [Accepted: 11/08/2019] [Indexed: 10/25/2022]
Abstract
Role of GADD34, a protein that is induced following cellular stress, in HIV-1 replication was investigated. GADD34 was induced during the late phase of HIV-1 infection. siRNA-knockdown of GADD34 stimulated whereas overexpression of GADD34 inhibited HIV-1 replication. GADD34 N-terminal ER-binding-helix amino acid region 1-192 alone was found to be sufficient for the inhibition of HIV-1 replication whereas protein-phosphatase -1-binding domain and eIF-2α-phosphatase activity of GADD34 were not crucial for anti-HIV-1 activity. GADD34 did not alter the HIV-1 RNA levels but reduced the viral protein expression suggesting that GADD34 interferes in HIV protein synthesis. Studies on the effect of HIV-1-5'-UTR and its mutants on a human promoter-driven luciferase expression indicated that GADD34-inhibition was mediated by 5'-UTR/TAR RNA, probably by modulating TAR RNA structure. In summary, our data support a novel function of GADD34 as a putative anti-HIV-1 restriction factor.
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Affiliation(s)
- Mohammad Ishaq
- Laboratory of Molecular Cell Biology, Leidos Biomedical Research Inc, Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD, 21702, USA.
| | - Heather Marshall
- Laboratory of Molecular Cell Biology, Leidos Biomedical Research Inc, Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD, 21702, USA
| | - Ven Natarajan
- Laboratory of Molecular Cell Biology, Leidos Biomedical Research Inc, Frederick National Laboratory for Cancer Research, P.O. Box B, Frederick, MD, 21702, USA.
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17
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Paes W, Leonov G, Partridge T, Chikata T, Murakoshi H, Frangou A, Brackenridge S, Nicastri A, Smith AG, Learn GH, Li Y, Parker R, Oka S, Pellegrino P, Williams I, Haynes BF, McMichael AJ, Shaw GM, Hahn BH, Takiguchi M, Ternette N, Borrow P. Contribution of proteasome-catalyzed peptide cis-splicing to viral targeting by CD8 + T cells in HIV-1 infection. Proc Natl Acad Sci U S A 2019; 116:24748-24759. [PMID: 31748275 PMCID: PMC6900506 DOI: 10.1073/pnas.1911622116] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Peptides generated by proteasome-catalyzed splicing of noncontiguous amino acid sequences have been shown to constitute a source of nontemplated human leukocyte antigen class I (HLA-I) epitopes, but their role in pathogen-specific immunity remains unknown. CD8+ T cells are key mediators of HIV type 1 (HIV-1) control, and identification of novel epitopes to enhance targeting of infected cells is a priority for prophylactic and therapeutic strategies. To explore the contribution of proteasome-catalyzed peptide splicing (PCPS) to HIV-1 epitope generation, we developed a broadly applicable mass spectrometry-based discovery workflow that we employed to identify spliced HLA-I-bound peptides on HIV-infected cells. We demonstrate that HIV-1-derived spliced peptides comprise a relatively minor component of the HLA-I-bound viral immunopeptidome. Although spliced HIV-1 peptides may elicit CD8+ T cell responses relatively infrequently during infection, CD8+ T cells primed by partially overlapping contiguous epitopes in HIV-infected individuals were able to cross-recognize spliced viral peptides, suggesting a potential role for PCPS in restricting HIV-1 escape pathways. Vaccine-mediated priming of responses to spliced HIV-1 epitopes could thus provide a novel means of exploiting epitope targets typically underutilized during natural infection.
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Affiliation(s)
- Wayne Paes
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom;
| | - German Leonov
- York Cross-Disciplinary Centre for Systems Analysis, University of York, York YO10 5DD, United Kingdom
| | - Thomas Partridge
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom
| | - Takayuki Chikata
- Centre for AIDS Research, Kumamoto University, Kumamoto 860-0811, Japan
| | - Hayato Murakoshi
- Centre for AIDS Research, Kumamoto University, Kumamoto 860-0811, Japan
| | - Anna Frangou
- Big Data Institute, University of Oxford, Oxford OX3 7LF, United Kingdom
| | - Simon Brackenridge
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom
| | - Annalisa Nicastri
- Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Andrew G Smith
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Gerald H Learn
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Yingying Li
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Robert Parker
- Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Shinichi Oka
- Centre for AIDS Research, Kumamoto University, Kumamoto 860-0811, Japan
- AIDS Clinical Centre, National Centre for Global Health and Medicine, Tokyo 162-8655, Japan
| | - Pierre Pellegrino
- Centre for Sexual Health and HIV Research, University College London, London WC1E 6JB, United Kingdom
| | - Ian Williams
- Centre for Sexual Health and HIV Research, University College London, London WC1E 6JB, United Kingdom
| | - Barton F Haynes
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710
| | - Andrew J McMichael
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom
| | - George M Shaw
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Beatrice H Hahn
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | | | - Nicola Ternette
- Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, United Kingdom;
| | - Persephone Borrow
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7FZ, United Kingdom;
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18
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Differentiation into an Effector Memory Phenotype Potentiates HIV-1 Latency Reversal in CD4 + T Cells. J Virol 2019; 93:JVI.00969-19. [PMID: 31578289 PMCID: PMC6880164 DOI: 10.1128/jvi.00969-19] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 09/15/2019] [Indexed: 12/12/2022] Open
Abstract
By performing phenotypic analysis of latency reversal in CD4+ T cells from virally suppressed individuals, we identify the TEM subset as the largest contributor to the inducible HIV reservoir. Differential responses of memory CD4+ T cell subsets to latency-reversing agents (LRAs) demonstrate that HIV gene expression is associated with heightened expression of transcriptional pathways associated with differentiation, acquisition of effector function, and cell cycle entry. In vitro modeling of the latent HIV reservoir in memory CD4+ T cell subsets identify LRAs that reverse latency with ranges of efficiency and specificity. We found that therapeutic induction of latency reversal is associated with upregulation of identical sets of TEM-associated genes and cell surface markers shown to be associated with latency reversal in our ex vivo and in vitro models. Together, these data support the idea that the effector memory phenotype supports HIV latency reversal in CD4+ T cells. During antiretroviral therapy (ART), human immunodeficiency virus type 1 (HIV-1) persists as a latent reservoir in CD4+ T cell subsets in central memory (TCM), transitional memory (TTM), and effector memory (TEM) CD4+ T cells. We have identified differences in mechanisms underlying latency and responses to latency-reversing agents (LRAs) in ex vivo CD4+ memory T cells from virally suppressed HIV-infected individuals and in an in vitro primary cell model of HIV-1 latency. Our ex vivo and in vitro results demonstrate the association of transcriptional pathways of T cell differentiation, acquisition of effector function, and cell cycle entry in response to LRAs. Analyses of memory cell subsets showed that effector memory pathways and cell surface markers of activation and proliferation in the TEM subset are predictive of higher frequencies of cells carrying an inducible reservoir. Transcriptional profiling also demonstrated that the epigenetic machinery (known to control latency and reactivation) in the TEM subset is associated with frequencies of cells with HIV-integrated DNA and inducible HIV multispliced RNA. TCM cells were triggered to differentiate into TEM cells when they were exposed to LRAs, and this increase of TEM subset frequencies upon LRA stimulation was positively associated with higher numbers of p24+ cells. Together, these data highlight differences in underlying biological latency control in different memory CD4+ T cell subsets which harbor latent HIV in vivo and support a role for differentiation into a TEM phenotype in facilitating latency reversal. IMPORTANCE By performing phenotypic analysis of latency reversal in CD4+ T cells from virally suppressed individuals, we identify the TEM subset as the largest contributor to the inducible HIV reservoir. Differential responses of memory CD4+ T cell subsets to latency-reversing agents (LRAs) demonstrate that HIV gene expression is associated with heightened expression of transcriptional pathways associated with differentiation, acquisition of effector function, and cell cycle entry. In vitro modeling of the latent HIV reservoir in memory CD4+ T cell subsets identify LRAs that reverse latency with ranges of efficiency and specificity. We found that therapeutic induction of latency reversal is associated with upregulation of identical sets of TEM-associated genes and cell surface markers shown to be associated with latency reversal in our ex vivo and in vitro models. Together, these data support the idea that the effector memory phenotype supports HIV latency reversal in CD4+ T cells.
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19
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Wonderlich ER, Subramanian K, Cox B, Wiegand A, Lackman-Smith C, Bale MJ, Stone M, Hoh R, Kearney MF, Maldarelli F, Deeks SG, Busch MP, Ptak RG, Kulpa DA. Effector memory differentiation increases detection of replication-competent HIV-l in resting CD4+ T cells from virally suppressed individuals. PLoS Pathog 2019; 15:e1008074. [PMID: 31609991 PMCID: PMC6812841 DOI: 10.1371/journal.ppat.1008074] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 10/24/2019] [Accepted: 09/10/2019] [Indexed: 12/15/2022] Open
Abstract
Studies have demonstrated that intensive ART alone is not capable of eradicating HIV-1, as the virus rebounds within a few weeks upon treatment interruption. Viral rebound may be induced from several cellular subsets; however, the majority of proviral DNA has been found in antigen experienced resting CD4+ T cells. To achieve a cure for HIV-1, eradication strategies depend upon both understanding mechanisms that drive HIV-1 persistence as well as sensitive assays to measure the frequency of infected cells after therapeutic interventions. Assays such as the quantitative viral outgrowth assay (QVOA) measure HIV-1 persistence during ART by ex vivo activation of resting CD4+ T cells to induce latency reversal; however, recent studies have shown that only a fraction of replication-competent viruses are inducible by primary mitogen stimulation. Previous studies have shown a correlation between the acquisition of effector memory phenotype and HIV-1 latency reversal in quiescent CD4+ T cell subsets that harbor the reservoir. Here, we apply our mechanistic understanding that differentiation into effector memory CD4+ T cells more effectively promotes HIV-1 latency reversal to significantly improve proviral measurements in the QVOA, termed differentiation QVOA (dQVOA), which reveals a significantly higher frequency of the inducible HIV-1 replication-competent reservoir in resting CD4+ T cells.
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Affiliation(s)
| | | | - Bryan Cox
- Department of Pediatrics, Emory University, Atlanta, Georgia, United States of America
| | - Ann Wiegand
- HIV DRP, NCI at Frederick, NIH, Frederick, Maryland, United States of America
| | | | - Michael J Bale
- HIV DRP, NCI at Frederick, NIH, Frederick, Maryland, United States of America
| | - Mars Stone
- Vitalant Research Institute, San Francisco, California, United States of America.,Department of Laboratory Medicine, University of California, San Francisco, San Francisco, California, United States of America
| | - Rebecca Hoh
- University of California, San Francisco (UCSF), San Francisco, California, United States of America
| | - Mary F Kearney
- HIV DRP, NCI at Frederick, NIH, Frederick, Maryland, United States of America
| | - Frank Maldarelli
- HIV DRP, NCI at Frederick, NIH, Frederick, Maryland, United States of America
| | - Steven G Deeks
- University of California, San Francisco (UCSF), San Francisco, California, United States of America
| | - Michael P Busch
- Vitalant Research Institute, San Francisco, California, United States of America.,Department of Laboratory Medicine, University of California, San Francisco, San Francisco, California, United States of America
| | - Roger G Ptak
- Southern Research, Frederick, Maryland, United States of America
| | - Deanna A Kulpa
- Department of Pediatrics, Emory University, Atlanta, Georgia, United States of America
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20
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Saha S, Hafren A, Mäkinen K. Dynamics of Protein Accumulation from the 3' End of Viral RNA Are Different from Those in the Rest of the Genome in Potato Virus A Infection. J Virol 2019; 93:e00721-19. [PMID: 31341041 PMCID: PMC6744237 DOI: 10.1128/jvi.00721-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/14/2019] [Indexed: 01/18/2023] Open
Abstract
One large open reading frame (ORF) encodes 10 potyviral proteins. We compared the accumulation of cylindrical inclusion (CI) protein from the middle, coat protein (CP) from the 3'end, and Renilla luciferase (RLUC) from two distinct locations in potato virus A (PVA) RNA. 5' RLUC was expressed from an rluc gene inserted between the P1 and helper component proteinase (HCPro) cistrons, and 3' RLUC was expressed from the gene inserted between the RNA polymerase and CP cistrons. Viral protein and RNA accumulation were quantitated (i) when expressed from PVA RNA in the presence of ectopically expressed genome-linked viral protein (VPg) and auxiliary proteins and (ii) at different time points during natural infection. The rate and timing of 3' RLUC and CP accumulation were found to be different from those of 5' RLUC and CI. Ectopic expression of VPg boosted PVA RNA, 3' RLUC, and, together with HCPro, CP accumulation, whereas 5' RLUC and CI accumulation remained unaffected regardless of the increased viral RNA amount. In natural infection, the rate of the noteworthy minute early accumulation of 3' RLUC accelerated toward the end of infection. 5' RLUC accumulation, which was already pronounced at 2 days postinfection, increased moderately and stabilized to a constant level by day 5, whereas PVA RNA and CP levels continued to increase throughout the infection. We propose that these observations connect with the mechanisms by which potyvirus infection limits CP accumulation during early infection and specifically supports its accumulation late in infection, but follow-up studies are required to understand the mechanism of how this occurs.IMPORTANCE The results of this study suggest that the dynamics of potyviral protein accumulation are regulated differentially from the 3' end of viral RNA than from the rest of the genome, the significance of which would be to satisfy the needs of replication early and particle assembly late in infection.
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Affiliation(s)
- Shreya Saha
- Faculty of Agriculture and Forestry, Department of Microbiology, Viikki Plant Sciences Center, University of Helsinki, Helsinki, Finland
| | - Anders Hafren
- Faculty of Agriculture and Forestry, Department of Microbiology, Viikki Plant Sciences Center, University of Helsinki, Helsinki, Finland
| | - Kristiina Mäkinen
- Faculty of Agriculture and Forestry, Department of Microbiology, Viikki Plant Sciences Center, University of Helsinki, Helsinki, Finland
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21
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Lyon K, Aguilera LU, Morisaki T, Munsky B, Stasevich TJ. Live-Cell Single RNA Imaging Reveals Bursts of Translational Frameshifting. Mol Cell 2019; 75:172-183.e9. [PMID: 31178355 DOI: 10.1016/j.molcel.2019.05.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/14/2019] [Accepted: 04/30/2019] [Indexed: 11/25/2022]
Abstract
Ribosomal frameshifting during the translation of RNA is implicated in human disease and viral infection. While previous work has uncovered many details about single RNA frameshifting kinetics in vitro, little is known about how single RNA frameshift in living systems. To confront this problem, we have developed technology to quantify live-cell single RNA translation dynamics in frameshifted open reading frames. Applying this technology to RNA encoding the HIV-1 frameshift sequence reveals a small subset (∼8%) of the translating pool robustly frameshift. Frameshifting RNA are translated at similar rates as non-frameshifting RNA (∼3 aa/s) and can continuously frameshift for more than four rounds of translation. Fits to a bursty model of frameshifting constrain frameshifting kinetic rates and demonstrate how ribosomal traffic jams contribute to the persistence of the frameshifting state. These data provide insight into retroviral frameshifting and could lead to alternative strategies to perturb the process in living cells.
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Affiliation(s)
- Kenneth Lyon
- Department of Biochemistry and Molecular Biology, Institute of Genome Architecture and Function, Colorado State University, Fort Collins, CO 80523, USA
| | - Luis U Aguilera
- Department of Chemical and Biological Engineering and School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523, USA
| | - Tatsuya Morisaki
- Department of Biochemistry and Molecular Biology, Institute of Genome Architecture and Function, Colorado State University, Fort Collins, CO 80523, USA
| | - Brian Munsky
- Department of Chemical and Biological Engineering and School of Biomedical Engineering, Colorado State University, Fort Collins, CO 80523, USA.
| | - Timothy J Stasevich
- Department of Biochemistry and Molecular Biology, Institute of Genome Architecture and Function, Colorado State University, Fort Collins, CO 80523, USA; World Research Hub Initiative, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Kanagawa 226-8503, Japan.
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22
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D Urbano V, De Crignis E, Re MC. Host Restriction Factors and Human Immunodeficiency Virus (HIV-1): A Dynamic Interplay Involving All Phases of the Viral Life Cycle. Curr HIV Res 2019; 16:184-207. [PMID: 30117396 DOI: 10.2174/1570162x16666180817115830] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 07/31/2018] [Accepted: 08/09/2018] [Indexed: 02/08/2023]
Abstract
Mammalian cells have evolved several mechanisms to prevent or block lentiviral infection and spread. Among the innate immune mechanisms, the signaling cascade triggered by type I interferon (IFN) plays a pivotal role in limiting the burden of HIV-1. In the presence of IFN, human cells upregulate the expression of a number of genes, referred to as IFN-stimulated genes (ISGs), many of them acting as antiviral restriction factors (RFs). RFs are dominant proteins that target different essential steps of the viral cycle, thereby providing an early line of defense against the virus. The identification and characterization of RFs have provided unique insights into the molecular biology of HIV-1, further revealing the complex host-pathogen interplay that characterizes the infection. The presence of RFs drove viral evolution, forcing the virus to develop specific proteins to counteract their activity. The knowledge of the mechanisms that prevent viral infection and their viral counterparts may offer new insights to improve current antiviral strategies. This review provides an overview of the RFs targeting HIV-1 replication and the mechanisms that regulate their expression as well as their impact on viral replication and the clinical course of the disease.
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Affiliation(s)
- Vanessa D Urbano
- Retrovirus Laboratory, Operative Unit of Clinical Microbiology, S. Orsola-Malpighi University Hospital, Bologna, Italy
| | - Elisa De Crignis
- Retrovirus Laboratory, Operative Unit of Clinical Microbiology, S. Orsola-Malpighi University Hospital, Bologna, Italy
| | - Maria Carla Re
- Retrovirus Laboratory, Operative Unit of Clinical Microbiology, S. Orsola-Malpighi University Hospital, Bologna, Italy
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Persistent Replication of HIV, Hepatitis C Virus (HCV), and HBV Results in Distinct Gene Expression Profiles by Human NK Cells. J Virol 2019; 93:JVI.00575-18. [PMID: 30185599 DOI: 10.1128/jvi.00575-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 08/20/2018] [Indexed: 01/14/2023] Open
Abstract
Natural killer (NK) cells during chronic viral infection have been well studied in the past. We performed an unbiased next-generation RNA-sequencing approach to identify commonalities or differences of the effect of HIV, HCV, and HBV viremia on NK cell transcriptomes. Using cell sorting, we obtained CD3- CD56+ NK cells from blood of 6 HIV-, 8 HCV-, and 32 HBV-infected patients without treatment. After library preparation and sequencing, we used an in-house analytic pipeline to compare expression levels with matched healthy controls. In NK cells from HIV-, HCV-, and HBV-infected patients, transcriptome analysis identified 272, 53, and 56 differentially expressed genes, respectively (fold change, >1.5; q-value, 0.2). Interferon-stimulated genes were induced in NK cells from HIV/HCV patients, but not during HBV infection. HIV viremia downregulated ribosome assembly genes in NK cells. In HBV-infected patients, viral load and alanine aminotransferase (ALT) variation had little effect on genes related to NK effector function. In conclusion, we compare, for the first time, NK cell transcripts of viremic HIV, HCV, and HBV patients. We clearly demonstrate distinctive NK cell gene signatures in three different populations, suggestive for a different degree of functional alterations of the NK cell compartment compared to healthy individuals.IMPORTANCE Three viruses exist that can result in persistently high viral loads in immunocompetent humans: human immunodeficiency virus (HIV), hepatitis C virus, and hepatitis B virus. In the last decades, by using flow cytometry and in vitro assays on NK cells from patients with these types of infections, several impairments have been established, particularly during and possibly contributing to HIV viremia. However, the background of NK cell impairments in viremic patients is not well understood. In this study, we describe the NK cell transcriptomes of patients with high viral loads of different etiologies. We clearly demonstrate distinctive NK cell gene signatures with regard to interferon-stimulated gene induction and the expression of genes coding for activation markers or proteins involved in cytotoxic action, as well immunological genes. This study provides important details necessary to uncover the origin of functional and phenotypical differences between viremic patients and healthy subjects and provides many leads that can be confirmed using future in vitro manipulation experiments.
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24
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Beitari S, Wang Y, Liu SL, Liang C. HIV-1 Envelope Glycoprotein at the Interface of Host Restriction and Virus Evasion. Viruses 2019; 11:v11040311. [PMID: 30935048 PMCID: PMC6521621 DOI: 10.3390/v11040311] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 12/15/2022] Open
Abstract
Without viral envelope proteins, viruses cannot enter cells to start infection. As the major viral proteins present on the surface of virions, viral envelope proteins are a prominent target of the host immune system in preventing and ultimately eliminating viral infection. In addition to the well-appreciated adaptive immunity that produces envelope protein-specific antibodies and T cell responses, recent studies have begun to unveil a rich layer of host innate immune mechanisms restricting viral entry. This review focuses on the exciting progress that has been made in this new direction of research, by discussing various known examples of host restriction of viral entry, and diverse viral countering strategies, in particular, the emerging role of viral envelope proteins in evading host innate immune suppression. We will also highlight the effective cooperation between innate and adaptive immunity to achieve the synergistic control of viral infection by targeting viral envelope protein and checking viral escape. Given that many of the related findings were made with HIV-1, we will use HIV-1 as the model virus to illustrate the basic principles and molecular mechanisms on host restriction targeting HIV-1 envelope protein.
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Affiliation(s)
- Saina Beitari
- Department of Microbiology & Immunology, McGill University, Montreal, QC H3A 2B4, Canada.
- Lady Davis Institute, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
| | - Yimeng Wang
- Lady Davis Institute, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada.
| | - Shan-Lu Liu
- Center for Retrovirus Research, Department of Veterinary Biosciences, Department of Microbial Infection and Immunity, The Ohio State University, Columbus, Ohio 43210, USA.
| | - Chen Liang
- Department of Microbiology & Immunology, McGill University, Montreal, QC H3A 2B4, Canada.
- Lady Davis Institute, Jewish General Hospital, Montreal, QC H3T 1E2, Canada.
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada.
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25
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Abstract
Human immunodeficiency virus-1 (HIV-1) is known to interact with multiple host cellular proteins during its replication in the target cell. While many of these host cellular proteins facilitate viral replication, a number of them are reported to inhibit HIV-1 replication at various stages of its life cycle. These host cellular proteins, which are known as restriction factors, constitute an integral part of the host's first line of defence against the viral pathogen. Since the discovery of apolipoprotein B mRNA-editing enzyme 3G (APOBEC3G) as an HIV-1 restriction factor, several human proteins have been identified that exhibit anti-HIV-1 restriction. While each restriction factor employs a distinct mechanism of inhibition, the HIV-1 virus has equally evolved complex counter strategies to neutralize their inhibitory effect. APOBEC3G, tetherin, sterile alpha motif and histidine-aspartate domain 1 (SAMHD1), and trim-5α are some of the best known HIV-1 restriction factors that have been studied in great detail. Recently, six novel restriction factors were discovered that exhibit significant antiviral activity: endoplasmic reticulum α1,2-mannosidase I (ERManI), translocator protein (TSPO), guanylate-binding protein 5 (GBP5), serine incorporator (SERINC3/5) and zinc-finger antiviral protein (ZAP). The focus of this review is to discuss the antiviral mechanism of action of these six restriction factors and provide insights into the probable counter-evasion strategies employed by the HIV-1 virus. The recent discovery of new restriction factors substantiates the complex host-pathogen interactions occurring during HIV-1 pathogenesis and makes it imperative that further investigations are conducted to elucidate the molecular basis of HIV-1 replication.
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Affiliation(s)
- Dibya Ghimire
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi 110021, India
| | - Madhu Rai
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi 110021, India
| | - Ritu Gaur
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi 110021, India
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26
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Deforges J, de Breyne S, Ameur M, Ulryck N, Chamond N, Saaidi A, Ponty Y, Ohlmann T, Sargueil B. Two ribosome recruitment sites direct multiple translation events within HIV1 Gag open reading frame. Nucleic Acids Res 2017; 45:7382-7400. [PMID: 28449096 PMCID: PMC5499600 DOI: 10.1093/nar/gkx303] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 04/12/2017] [Indexed: 02/06/2023] Open
Abstract
In the late phase of the HIV virus cycle, the unspliced genomic RNA is exported to the cytoplasm for the necessary translation of the Gag and Gag-pol polyproteins. Three distinct translation initiation mechanisms ensuring Gag production have been described with little rationale for their multiplicity. The Gag-IRES has the singularity to be located within Gag ORF and to directly interact with ribosomal 40S. Aiming at elucidating the specificity and the relevance of this interaction, we probed HIV-1 Gag-IRES structure and developed an innovative integrative modelling strategy to take into account all the gathered information. We propose a novel Gag-IRES secondary structure strongly supported by all experimental data. We further demonstrate the presence of two regions within Gag-IRES that independently and directly interact with the ribosome. Importantly, these binding sites are functionally relevant to Gag translation both in vitro and ex vivo. This work provides insight into the Gag-IRES molecular mechanism and gives compelling evidence for its physiological importance. It allows us to propose original hypotheses about the IRES physiological role and conservation among primate lentiviruses.
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Affiliation(s)
- Jules Deforges
- CNRS UMR 8015, Laboratoire de cristallographie et RMN Biologiques, Université Paris Descartes, 4 avenue de l'Observatoire, 75270 Paris Cedex 06, France
| | - Sylvain de Breyne
- CIRI (International Center for Infectiology Research), INSERM U1111, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5308, 46 allée d'Italie, 69364 Lyon Cedex 07, France
| | - Melissa Ameur
- CNRS UMR 8015, Laboratoire de cristallographie et RMN Biologiques, Université Paris Descartes, 4 avenue de l'Observatoire, 75270 Paris Cedex 06, France
| | - Nathalie Ulryck
- CNRS UMR 8015, Laboratoire de cristallographie et RMN Biologiques, Université Paris Descartes, 4 avenue de l'Observatoire, 75270 Paris Cedex 06, France
| | - Nathalie Chamond
- CNRS UMR 8015, Laboratoire de cristallographie et RMN Biologiques, Université Paris Descartes, 4 avenue de l'Observatoire, 75270 Paris Cedex 06, France
| | - Afaf Saaidi
- CNRS UMR 7161, Laboratoire de Recherche en Informatique de l'Ecole Polytechnique (LIX), Ecole Polytechnique, 1 rue Estienne d'Orves, 91120 Palaiseau, France.,AMIB, Inria Saclay, bat Alan Turing, 1 rue Estienne d'Orves, 91120 Palaiseau, France
| | - Yann Ponty
- CNRS UMR 7161, Laboratoire de Recherche en Informatique de l'Ecole Polytechnique (LIX), Ecole Polytechnique, 1 rue Estienne d'Orves, 91120 Palaiseau, France.,AMIB, Inria Saclay, bat Alan Turing, 1 rue Estienne d'Orves, 91120 Palaiseau, France
| | - Theophile Ohlmann
- CIRI (International Center for Infectiology Research), INSERM U1111, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5308, 46 allée d'Italie, 69364 Lyon Cedex 07, France
| | - Bruno Sargueil
- CNRS UMR 8015, Laboratoire de cristallographie et RMN Biologiques, Université Paris Descartes, 4 avenue de l'Observatoire, 75270 Paris Cedex 06, France
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27
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Regulation of Tacaribe Mammarenavirus Translation: Positive 5' and Negative 3' Elements and Role of Key Cellular Factors. J Virol 2017; 91:JVI.00084-17. [PMID: 28468879 DOI: 10.1128/jvi.00084-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 04/24/2017] [Indexed: 12/17/2022] Open
Abstract
Mammarenaviruses are enveloped viruses with a bisegmented negative-stranded RNA genome that encodes the nucleocapsid protein (NP), the envelope glycoprotein precursor (GPC), the RNA polymerase (L), and a RING matrix protein (Z). Viral proteins are synthesized from subgenomic mRNAs bearing a capped 5' untranslated region (UTR) and lacking 3' poly(A) tail. We analyzed the translation strategy of Tacaribe virus (TCRV), a prototype of the New World mammarenaviruses. A virus-like transcript that carries a reporter gene in place of the NP open reading frame and transcripts bearing modified 5' and/or 3' UTR were evaluated in a cell-based translation assay. We found that the presence of the cap structure at the 5' end dramatically increases translation efficiency and that the viral 5' UTR comprises stimulatory signals while the 3' UTR,specifically the presence of a terminal C+G-rich sequence and/or a stem-loop structure, down-modulates translation. Additionally, translation was profoundly reduced in eukaryotic initiation factor (eIF) 4G-inactivated cells, whereas depletion of intracellular levels of eIF4E had less impact on virus-like mRNA translation than on a cell-like transcript. Translation efficiency was independent of NP expression or TCRV infection. Our results indicate that TCRV mRNAs are translated using a cap-dependent mechanism, whose efficiency relies on the interplay between stimulatory signals in the 5' UTR and a negative modulatory element in the 3' UTR. The low dependence on eIF4E suggests that viral mRNAs may engage yet-unknown noncanonical host factors for a cap-dependent initiation mechanism.IMPORTANCE Several members of the Arenaviridae family cause serious hemorrhagic fevers in humans. In the present report, we describe the mechanism by which Tacaribe virus, a prototypic nonpathogenic New World mammarenavirus, regulates viral mRNA translation. Our results highlight the impact of untranslated sequences and key host translation factors on this process. We propose a model that explains how viral mRNAs outcompete cellular mRNAs for the translation machinery. A better understanding of the mechanism of translation regulation of this virus can provide the bases for the rational design of new antiviral tools directed to pathogenic arenaviruses.
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Translational regulation of APOBEC3G mRNA by Vif requires its 5'UTR and contributes to restoring HIV-1 infectivity. Sci Rep 2016; 6:39507. [PMID: 27996044 PMCID: PMC5171582 DOI: 10.1038/srep39507] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 11/23/2016] [Indexed: 12/12/2022] Open
Abstract
The essential HIV-1 viral infectivity factor (Vif) allows productive infection of non-permissive cells expressing cytidine deaminases APOBEC3G (A3G) and A3F by decreasing their cellular level, and preventing their incorporation into virions. Unlike the Vif-induced degradation of A3G, the functional role of the inhibition of A3G translation by Vif remained unclear. Here, we show that two stem-loop structures within the 5′-untranslated region of A3G mRNA are crucial for translation inhibition by Vif in cells, and most Vif alleles neutralize A3G translation efficiently. Interestingly, K26R mutation in Vif abolishes degradation of A3G by the proteasome but has no effect at the translational level, indicating these two pathways are independent. These two mechanisms, proteasomal degradation and translational inhibition, similarly contribute to decrease the cellular level of A3G by Vif and to prevent its incorporation into virions. Importantly, inhibition of A3G translation is sufficient to partially restore viral infectivity in the absence of proteosomal degradation. These findings demonstrate that HIV-1 has evolved redundant mechanisms to specifically inhibit the potent antiviral activity of A3G.
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29
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Blin J, Ricci EP. [An intimate look at the viral replication cycle through ribosome profiling]. Med Sci (Paris) 2016; 32:849-860. [PMID: 27758749 DOI: 10.1051/medsci/20163210018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Next Generation Sequencing (NGS) techniques have revolutionized most biomedical research fields over the past decade by allowing a broader vision on biological processes that occur at the molecular level. Among these, ribosome profiling or footprinting is a powerful tool to study mRNA translation in a transcriptome-wide manner. Ribosome profiling has been used to study the impact of translational control of gene expression under many different cellular conditions including viral infections. Indeed, translation is a critical step during the viral replication cycle in which the infected cell is embezzled to produce viral proteins. Ribosome profiling tools can provide new insights on viral translation by monitoring ribosome binding to viral and cellular RNAs with a high definition during the time course of an infection. Here, we describe the potential uses of ribosome profiling for the understanding of viral translational control and the impact of viral infection on host gene expression. We also discuss the main limitations and biases related to the technique that need to be taken into account for its use.
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Affiliation(s)
- Juliana Blin
- CIRI, international center for infectiology research, université de Lyon, 46, allée d'Italie, Lyon, France
| | - Emiliano P Ricci
- CIRI, international center for infectiology research, université de Lyon, 46, allée d'Italie, Lyon, France - Inserm, U1111, Lyon, France - École normale supérieure de Lyon, 46, allée d'Italie, 69007 Lyon, France - Université Claude Bernard Lyon 1, centre international de recherche en infectiologie, Lyon, France - CNRS, UMR5308, Lyon, France
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30
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Qiao Q, Yan Y, Guo J, Du S, Zhang J, Jia R, Ren H, Qiao Y, Li Q. A review on architecture of the gag-pol ribosomal frameshifting RNA in human immunodeficiency virus: a variability survey of virus genotypes. J Biomol Struct Dyn 2016; 35:1629-1653. [PMID: 27485859 DOI: 10.1080/07391102.2016.1194231] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Programmed '-1' ribosomal frameshifting is necessary for expressing the pol gene overlapped from a gag of human immunodeficiency virus. A viral RNA structure that requires base pairing across the overlapping sequence region suggests a mechanism of regulating ribosome and helicase traffic during expression. To get precise roles of an element around the frameshift site, a review on architecture of the frameshifting RNA is performed in combination of reported information with augments of a representative set of 19 viral samples. In spite of a different length for the viral RNAs, a canonical comparison on the element sequence allocation is performed for viewing variability associations between virus genotypes. Additionally, recent and historical insights recognized in frameshifting regulation are looked back as for indel and single nucleotide polymorphism of RNA. As specially noted, structural changes at a frameshift site, the spacer sequence, and a three-helix junction element, as well as two Watson-Crick base pairs near a bulge and a C-G pair close a loop, are the most vital strategies for the virus frameshifting regulations. All of structural changes, which are dependent upon specific sequence variations, facilitate an elucidation about the RNA element conformation-dependent mechanism for frameshifting. These facts on disrupting base pair interactions also allow solving the problem of competition between ribosome and helicase on a same RNA template, common to single-stranded RNA viruses. In a broad perspective, each new insight of frameshifting regulation in the competition systems introduced by the RNA element construct changes will offer a compelling target for antiviral therapy.
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Affiliation(s)
- Qi Qiao
- a School of Pharmaceutical Sciences, Xiamen University , Fujian 361102 , P.R. China
| | - Yanhua Yan
- b Department of Bioscience , Luliang University , Shanxi 033001 , P.R. China
| | - Jinmei Guo
- c Department of Chemistry & Chemical Engineering , Luliang University , Shanxi 033001 , P.R. China
| | - Shuqiang Du
- c Department of Chemistry & Chemical Engineering , Luliang University , Shanxi 033001 , P.R. China
| | - Jiangtao Zhang
- b Department of Bioscience , Luliang University , Shanxi 033001 , P.R. China
| | - Ruyue Jia
- c Department of Chemistry & Chemical Engineering , Luliang University , Shanxi 033001 , P.R. China
| | - Haimin Ren
- c Department of Chemistry & Chemical Engineering , Luliang University , Shanxi 033001 , P.R. China
| | - Yuanbiao Qiao
- d Graduate Institute of Pharmaceutical Chemistry, Luliang University , Shanxi 033001 , P.R. China
| | - Qingshan Li
- e School of Pharmaceutical Sciences , Shanxi Medical University , Shanxi 030001 , P.R. China
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31
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Carvajal F, Vallejos M, Walters B, Contreras N, Hertz MI, Olivares E, Cáceres CJ, Pino K, Letelier A, Thompson SR, López-Lastra M. Structural domains within the HIV-1 mRNA and the ribosomal protein S25 influence cap-independent translation initiation. FEBS J 2016; 283:2508-27. [PMID: 27191820 DOI: 10.1111/febs.13756] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 04/28/2016] [Accepted: 05/13/2016] [Indexed: 12/14/2022]
Abstract
The 5' leader of the HIV-1 genomic RNA is a multifunctional region that folds into secondary/tertiary structures that regulate multiple processes during viral replication including translation initiation. In this work, we examine the internal ribosome entry site (IRES) located in the 5' leader that drives translation initiation of the viral Gag protein under conditions that hinder cap-dependent translation initiation. We show that activity of the HIV-1 IRES relies on ribosomal protein S25 (eS25). Additionally, a mechanistic and mutational analysis revealed that the HIV-1 IRES is modular in nature and that once the 40S ribosomal subunit is recruited to the IRES, translation initiates without the need of ribosome scanning. These findings elucidate a mechanism of initiation by the HIV-1 IRES whereby a number of highly structured sites present within the HIV-1 5' leader leads to the recruitment of the 40S subunit directly at the site of initiation of protein synthesis.
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Affiliation(s)
- Felipe Carvajal
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Maricarmen Vallejos
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Beth Walters
- Department of Microbiology, University of Alabama at Birmingham, AL, USA
| | - Nataly Contreras
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marla I Hertz
- Department of Microbiology, University of Alabama at Birmingham, AL, USA
| | - Eduardo Olivares
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos J Cáceres
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Karla Pino
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alejandro Letelier
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Sunnie R Thompson
- Department of Microbiology, University of Alabama at Birmingham, AL, USA
| | - Marcelo López-Lastra
- Laboratorio de Virología Molecular, Instituto Milenio de Inmunología e Inmunoterapia, Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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32
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Hotter D, Sauter D, Kirchhoff F. Guanylate binding protein 5: Impairing virion infectivity by targeting retroviral envelope glycoproteins. Small GTPases 2016; 8:31-37. [PMID: 27275775 PMCID: PMC5331900 DOI: 10.1080/21541248.2016.1189990] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Guanylate binding proteins (GBPs) are interferon-inducible cellular factors that belong to the superfamily of guanosine triphosphatases (GTPases) and play important roles in the cell-intrinsic defense against bacteria, protozoa and viruses. In a recent report in Cell Host & Microbe, we identify GBP5 as novel restriction factor of HIV-1 that reduces the infectivity of progeny virions by interfering with processing and incorporation of the viral envelope (Env) glycoprotein. The inhibitory activity of GBP5 requires C-terminal isoprenylation, mediating Golgi-association, but not its GTPase function. Notably, GBP5 expression levels vary considerably in human macrophages and inversely correlate with infectious virus yield. We demonstrate that GBP5 can be evaded by an unusual tradeoff mechanism: Naturally occurring mutations in the start codon of the viral accessory gene vpu attenuate GBP5 inhibition by increasing Env expression at the cost of Vpu function. Whether direct counteraction mechanisms or more subtle changes balancing Vpu and Env expression also affect HIV-1 inhibition by GBP5 remains to be clarified. Other open questions are whether GBP5 restricts HIV-1 in CD4+ T cells and if other GBP family members also decrease infectivity of HIV and/or additional enveloped viruses.
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Affiliation(s)
- Dominik Hotter
- a Institute of Molecular Virology, Ulm University Medical Center , Ulm , Germany
| | - Daniel Sauter
- a Institute of Molecular Virology, Ulm University Medical Center , Ulm , Germany
| | - Frank Kirchhoff
- a Institute of Molecular Virology, Ulm University Medical Center , Ulm , Germany
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33
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HIV-1 and M-PMV RNA Nuclear Export Elements Program Viral Genomes for Distinct Cytoplasmic Trafficking Behaviors. PLoS Pathog 2016; 12:e1005565. [PMID: 27070420 PMCID: PMC4829213 DOI: 10.1371/journal.ppat.1005565] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 03/21/2016] [Indexed: 12/15/2022] Open
Abstract
Retroviruses encode cis-acting RNA nuclear export elements that override nuclear retention of intron-containing viral mRNAs including the full-length, unspliced genomic RNAs (gRNAs) packaged into assembling virions. The HIV-1 Rev-response element (RRE) recruits the cellular nuclear export receptor CRM1 (also known as exportin-1/XPO1) using the viral protein Rev, while simple retroviruses encode constitutive transport elements (CTEs) that directly recruit components of the NXF1(Tap)/NXT1(p15) mRNA nuclear export machinery. How gRNA nuclear export is linked to trafficking machineries in the cytoplasm upstream of virus particle assembly is unknown. Here we used long-term (>24 h), multicolor live cell imaging to directly visualize HIV-1 gRNA nuclear export, translation, cytoplasmic trafficking, and virus particle production in single cells. We show that the HIV-1 RRE regulates unique, en masse, Rev- and CRM1-dependent "burst-like" transitions of mRNAs from the nucleus to flood the cytoplasm in a non-localized fashion. By contrast, the CTE derived from Mason-Pfizer monkey virus (M-PMV) links gRNAs to microtubules in the cytoplasm, driving them to cluster markedly to the centrosome that forms the pericentriolar core of the microtubule-organizing center (MTOC). Adding each export element to selected heterologous mRNAs was sufficient to confer each distinct export behavior, as was directing Rev/CRM1 or NXF1/NXT1 transport modules to mRNAs using a site-specific RNA tethering strategy. Moreover, multiple CTEs per transcript enhanced MTOC targeting, suggesting that a cooperative mechanism links NXF1/NXT1 to microtubules. Combined, these results reveal striking, unexpected features of retroviral gRNA nucleocytoplasmic transport and demonstrate roles for mRNA export elements that extend beyond nuclear pores to impact gRNA distribution in the cytoplasm.
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34
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Krapp C, Hotter D, Gawanbacht A, McLaren PJ, Kluge SF, Stürzel CM, Mack K, Reith E, Engelhart S, Ciuffi A, Hornung V, Sauter D, Telenti A, Kirchhoff F. Guanylate Binding Protein (GBP) 5 Is an Interferon-Inducible Inhibitor of HIV-1 Infectivity. Cell Host Microbe 2016; 19:504-14. [PMID: 26996307 DOI: 10.1016/j.chom.2016.02.019] [Citation(s) in RCA: 167] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 02/02/2016] [Accepted: 02/26/2016] [Indexed: 12/26/2022]
Abstract
Guanylate binding proteins (GBPs) are an interferon (IFN)-inducible subfamily of guanosine triphosphatases (GTPases) with well-established activity against intracellular bacteria and parasites. Here we show that GBP5 potently restricts HIV-1 and other retroviruses. GBP5 is expressed in the primary target cells of HIV-1, where it impairs viral infectivity by interfering with the processing and virion incorporation of the viral envelope glycoprotein (Env). GBP5 levels in macrophages determine and inversely correlate with infectious HIV-1 yield over several orders of magnitude, which may explain the high donor variability in macrophage susceptibility to HIV. Antiviral activity requires Golgi localization of GBP5, but not its GTPase activity. Start codon mutations in the accessory vpu gene from macrophage-tropic HIV-1 strains conferred partial resistance to GBP5 inhibition by increasing Env expression. Our results identify GBP5 as an antiviral effector of the IFN response and may explain the increased frequency of defective vpu genes in primary HIV-1 strains.
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Affiliation(s)
- Christian Krapp
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Dominik Hotter
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Ali Gawanbacht
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Paul J McLaren
- National HIV and Retrovirology Laboratory, Public Health Agency of Canada, Winnipeg, MB R3E 3P6, Canada
| | - Silvia F Kluge
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Christina M Stürzel
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Katharina Mack
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Elisabeth Reith
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Susanne Engelhart
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Angela Ciuffi
- Institute of Microbiology, University Hospital Center, University of Lausanne, 1015 Switzerland
| | - Veit Hornung
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-University Munich, 81377 Munich, Germany
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Amalio Telenti
- J. Craig Venter Institute, Capricorn Ln, La Jolla, CA 92037, USA
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany.
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35
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Nakano K, Watanabe T. HTLV-1 Rex Tunes the Cellular Environment Favorable for Viral Replication. Viruses 2016; 8:58. [PMID: 26927155 PMCID: PMC4810248 DOI: 10.3390/v8030058] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 02/09/2016] [Accepted: 02/09/2016] [Indexed: 12/18/2022] Open
Abstract
Human T-cell leukemia virus type-1 (HTLV-1) Rex is a viral RNA binding protein. The most important and well-known function of Rex is stabilizing and exporting viral mRNAs from the nucleus, particularly for unspliced/partially-spliced mRNAs encoding the structural proteins essential for viral replication. Without Rex, these unspliced viral mRNAs would otherwise be completely spliced. Therefore, Rex is vital for the translation of structural proteins and the stabilization of viral genomic RNA and, thus, for viral replication. Rex schedules the period of extensive viral replication and suppression to enter latency. Although the importance of Rex in the viral life-cycle is well understood, the underlying molecular mechanism of how Rex achieves its function has not been clarified. For example, how does Rex protect unspliced/partially-spliced viral mRNAs from the host cellular splicing machinery? How does Rex protect viral mRNAs, antigenic to eukaryotic cells, from cellular mRNA surveillance mechanisms? Here we will discuss these mechanisms, which explain the function of Rex as an organizer of HTLV-1 expression based on previously and recently discovered aspects of Rex. We also focus on the potential influence of Rex on the homeostasis of the infected cell and how it can exert its function.
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Affiliation(s)
- Kazumi Nakano
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 4-6-1, Shirokanedai, Minatoku, Tokyo 108-8639, Japan.
| | - Toshiki Watanabe
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, 4-6-1, Shirokanedai, Minatoku, Tokyo 108-8639, Japan.
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Mouilleron H, Delcourt V, Roucou X. Death of a dogma: eukaryotic mRNAs can code for more than one protein. Nucleic Acids Res 2016; 44:14-23. [PMID: 26578573 PMCID: PMC4705651 DOI: 10.1093/nar/gkv1218] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 10/26/2015] [Accepted: 10/28/2015] [Indexed: 12/13/2022] Open
Abstract
mRNAs carry the genetic information that is translated by ribosomes. The traditional view of a mature eukaryotic mRNA is a molecule with three main regions, the 5' UTR, the protein coding open reading frame (ORF) or coding sequence (CDS), and the 3' UTR. This concept assumes that ribosomes translate one ORF only, generally the longest one, and produce one protein. As a result, in the early days of genomics and bioinformatics, one CDS was associated with each protein-coding gene. This fundamental concept of a single CDS is being challenged by increasing experimental evidence indicating that annotated proteins are not the only proteins translated from mRNAs. In particular, mass spectrometry (MS)-based proteomics and ribosome profiling have detected productive translation of alternative open reading frames. In several cases, the alternative and annotated proteins interact. Thus, the expression of two or more proteins translated from the same mRNA may offer a mechanism to ensure the co-expression of proteins which have functional interactions. Translational mechanisms already described in eukaryotic cells indicate that the cellular machinery is able to translate different CDSs from a single viral or cellular mRNA. In addition to summarizing data showing that the protein coding potential of eukaryotic mRNAs has been underestimated, this review aims to challenge the single translated CDS dogma.
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Affiliation(s)
- Hélène Mouilleron
- Department of biochemistry, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec, Canada
| | - Vivian Delcourt
- Department of biochemistry, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec, Canada Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université de Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France
| | - Xavier Roucou
- Department of biochemistry, Université de Sherbrooke, Sherbrooke, Quebec J1E 4K8, Canada PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec, Canada
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Langer SM, Hopfensperger K, Iyer SS, Kreider EF, Learn GH, Lee LH, Hahn BH, Sauter D. A Naturally Occurring rev1-vpu Fusion Gene Does Not Confer a Fitness Advantage to HIV-1. PLoS One 2015; 10:e0142118. [PMID: 26554585 PMCID: PMC4640844 DOI: 10.1371/journal.pone.0142118] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 10/16/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Pandemic strains of HIV-1 (group M) encode a total of nine structural (gag, pol, env), regulatory (rev, tat) and accessory (vif, vpr, vpu, nef) genes. However, some subtype A and C viruses exhibit an unusual gene arrangement in which the first exon of rev (rev1) and the vpu gene are placed in the same open reading frame. Although this rev1-vpu gene fusion is present in a considerable fraction of HIV-1 strains, its functional significance is unknown. RESULTS Examining infectious molecular clones (IMCs) of HIV-1 that encode the rev1-vpu polymorphism, we show that a fusion protein is expressed in infected cells. Due to the splicing pattern of viral mRNA, however, these same IMCs also express a regular Vpu protein, which is produced at much higher levels. To investigate the function of the fusion gene, we characterized isogenic IMC pairs differing only in their ability to express a Rev1-Vpu protein. Analysis in transfected HEK293T and infected CD4+ T cells showed that all of these viruses were equally active in known Vpu functions, such as down-modulation of CD4 or counteraction of tetherin. Furthermore, the polymorphism did not affect Vpu-mediated inhibition of NF-кB activation or Rev-dependent nuclear export of incompletely spliced viral mRNAs. There was also no evidence for enhanced replication of Rev1-Vpu expressing viruses in primary PBMCs or ex vivo infected human lymphoid tissues. Finally, the frequency of HIV-1 quasispecies members that encoded a rev1-vpu fusion gene did not change in HIV-1 infected individuals over time. CONCLUSIONS Expression of a rev1-vpu fusion gene does not affect regular Rev and Vpu functions or alter HIV-1 replication in primary target cells. Since there is no evidence for increased replication fitness of rev1-vpu encoding viruses, this polymorphism likely emerged in the context of other mutations within and/or outside the rev1-vpu intergenic region, and may have a neutral phenotype.
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Affiliation(s)
- Simon M. Langer
- Institute of Molecular Virology, Ulm University Medical Center, 89081, Ulm, Germany
| | | | - Shilpa S. Iyer
- Departments of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Edward F. Kreider
- Departments of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Gerald H. Learn
- Departments of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Lan-Hui Lee
- Institute of Molecular Virology, Ulm University Medical Center, 89081, Ulm, Germany
- Department of Laboratory, Kunming Branch, Taipei City Hospital, 10844, Taipei, Taiwan
| | - Beatrice H. Hahn
- Departments of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, 19104, United States of America
| | - Daniel Sauter
- Institute of Molecular Virology, Ulm University Medical Center, 89081, Ulm, Germany
- * E-mail:
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Rojas-Araya B, Ohlmann T, Soto-Rifo R. Translational Control of the HIV Unspliced Genomic RNA. Viruses 2015; 7:4326-51. [PMID: 26247956 PMCID: PMC4576183 DOI: 10.3390/v7082822] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 05/18/2015] [Accepted: 07/17/2015] [Indexed: 01/16/2023] Open
Abstract
Post-transcriptional control in both HIV-1 and HIV-2 is a highly regulated process that commences in the nucleus of the host infected cell and finishes by the expression of viral proteins in the cytoplasm. Expression of the unspliced genomic RNA is particularly controlled at the level of RNA splicing, export, and translation. It appears increasingly obvious that all these steps are interconnected and they result in the building of a viral ribonucleoprotein complex (RNP) that must be efficiently translated in the cytosolic compartment. This review summarizes our knowledge about the genesis, localization, and expression of this viral RNP.
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Affiliation(s)
- Bárbara Rojas-Araya
- Molecular and Cellular Virology Laboratory, Program of Virology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Independencia 834100, Santiago, Chile.
| | - Théophile Ohlmann
- CIRI, International Center for Infectiology Research, Université de Lyon, Lyon 69007, France.
- Inserm, U1111, Lyon 69007, France.
- Ecole Normale Supérieure de Lyon, Lyon 69007, France.
- Université Lyon 1, Centre International de Recherche en Infectiologie, Lyon 69007, France.
- CNRS, UMR5308, Lyon 69007, France.
| | - Ricardo Soto-Rifo
- Molecular and Cellular Virology Laboratory, Program of Virology, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Independencia 834100, Santiago, Chile.
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