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Benoni B, Potužník J, Škríba A, Benoni R, Trylcova J, Tulpa M, Spustová K, Grab K, Mititelu MB, Pačes J, Weber J, Stanek D, Kowalska J, Bednarova L, Keckesova Z, Vopalensky P, Gahurova L, Cahova H. HIV-1 Infection Reduces NAD Capping of Host Cell snRNA and snoRNA. ACS Chem Biol 2024; 19:1243-1249. [PMID: 38747804 PMCID: PMC11197007 DOI: 10.1021/acschembio.4c00151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 05/09/2024] [Accepted: 05/10/2024] [Indexed: 06/22/2024]
Abstract
Nicotinamide adenine dinucleotide (NAD) is a critical component of the cellular metabolism and also serves as an alternative 5' cap on various RNAs. However, the function of the NAD RNA cap is still under investigation. We studied NAD capping of RNAs in HIV-1-infected cells because HIV-1 is responsible for the depletion of the NAD/NADH cellular pool and causing intracellular pellagra. By applying the NAD captureSeq protocol to HIV-1-infected and uninfected cells, we revealed that four snRNAs (e.g., U1) and four snoRNAs lost their NAD cap when infected with HIV-1. Here, we provide evidence that the presence of the NAD cap decreases the stability of the U1/HIV-1 pre-mRNA duplex. Additionally, we demonstrate that reducing the quantity of NAD-capped RNA by overexpressing the NAD RNA decapping enzyme DXO results in an increase in HIV-1 infectivity. This suggests that NAD capping is unfavorable for HIV-1 and plays a role in its infectivity.
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Affiliation(s)
- Barbora Benoni
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
- First
Faculty of Medicine, Charles University, Kateřinská 32, 121 08 Prague, Czechia
| | - Jiří
František Potužník
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
- Faculty
of Science, Department of Cell Biology, Charles University, Viničná 7, 121 08 Prague 2, Czechia
| | - Anton Škríba
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Roberto Benoni
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Jana Trylcova
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Matouš Tulpa
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
- Faculty
of Science, Department of Physical and Macromolecular Chemistry, Charles University, Hlavova 8, 121 08 Prague 2, Czechia
| | - Kristína Spustová
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Katarzyna Grab
- Division
of Biophysics, Faculty of Physics, University
of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Maria-Bianca Mititelu
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
- Faculty
of Science, Department of Cell Biology, Charles University, Viničná 7, 121 08 Prague 2, Czechia
| | - Jan Pačes
- Institute
of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czechia
| | - Jan Weber
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - David Stanek
- Institute
of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czechia
| | - Joanna Kowalska
- Division
of Biophysics, Faculty of Physics, University
of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Lucie Bednarova
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Zuzana Keckesova
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Pavel Vopalensky
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
| | - Lenka Gahurova
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
- Department
of Molecular Biology and Genetics, Faculty of Science, University of South Bohemia, Branišovská 1760, 37005 České Budějovice, Czechia
| | - Hana Cahova
- Institute
of Organic Chemistry and Biochemistry of the CAS, Flemingovo náměstí
2, 160 00 Prague
6, Czechia
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2
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Alpuche-Lazcano SP, Scarborough RJ, Gatignol A. MicroRNAs and long non-coding RNAs during transcriptional regulation and latency of HIV and HTLV. Retrovirology 2024; 21:5. [PMID: 38424561 PMCID: PMC10905857 DOI: 10.1186/s12977-024-00637-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 02/21/2024] [Indexed: 03/02/2024] Open
Abstract
Human immunodeficiency virus (HIV) and human T cell leukemia virus (HTLV) have replicative and latent stages of infection. The status of the viruses is dependent on the cells that harbour them and on different events that change the transcriptional and post-transcriptional events. Non-coding (nc)RNAs are key factors in the regulation of retrovirus replication cycles. Notably, micro (mi)RNAs and long non-coding (lnc)RNAs are important regulators that can induce switches between active transcription-replication and latency of retroviruses and have important impacts on their pathogenesis. Here, we review the functions of miRNAs and lncRNAs in the context of HIV and HTLV. We describe how specific miRNAs and lncRNAs are involved in the regulation of the viruses' transcription, post-transcriptional regulation and latency. We further discuss treatment strategies using ncRNAs for HIV and HTLV long remission, reactivation or possible cure.
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Affiliation(s)
- Sergio P Alpuche-Lazcano
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, 3999, Côte Ste Catherine St., Montréal, QC, H3T 1E2, Canada
- Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, H4A 3J1, Canada
- National Research Council Canada, Montréal, QC, H4P 2R2, Canada
| | - Robert J Scarborough
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, 3999, Côte Ste Catherine St., Montréal, QC, H3T 1E2, Canada
- Department of Microbiology and Immunology, McGill University, Montréal, QC, H3A 2B4, Canada
| | - Anne Gatignol
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, 3999, Côte Ste Catherine St., Montréal, QC, H3T 1E2, Canada.
- Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC, H4A 3J1, Canada.
- Department of Medicine, Division of Infectious Diseases, McGill University, Montréal, QC, H4A 3J1, Canada.
- Department of Microbiology and Immunology, McGill University, Montréal, QC, H3A 2B4, Canada.
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3
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Chen MJ, Gatignol A, Scarborough RJ. The discovery and development of RNA-based therapies for treatment of HIV-1 infection. Expert Opin Drug Discov 2023; 18:163-179. [PMID: 36004505 DOI: 10.1080/17460441.2022.2117296] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Long-term control of HIV-1 infection can potentially be achieved using autologous stem cell transplants with gene-modified cells. Non-coding RNAs represent a diverse class of therapeutic agents including ribozymes, RNA aptamers and decoys, small interfering RNAs, short hairpin RNAs, and U1 interference RNAs that can be designed to inhibit HIV-1 replication. They have been engineered for delivery as drugs to complement current HIV-1 therapies and as gene therapies for a potential HIV-1 functional cure. AREAS COVERED This review surveys the past three decades of development of these RNA technologies with a focus on their efficacy and safety for treating HIV-1 infections. We describe the mechanisms of each RNA-based agent, targets they have been developed against, efforts to enhance their stability and efficacy, and we evaluate their performance in past and ongoing preclinical and clinical trials. EXPERT OPINION RNA-based technologies are among the top candidates for gene therapies where they can be stably expressed for long-term suppression of HIV-1. Advances in both gene and drug delivery strategies and improvements to non-coding RNA stability and antiviral properties will cooperatively drive forward progress in improving drug therapy and engineering HIV-1 resistant cells.
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Affiliation(s)
- Michelle J Chen
- Lady Davis Institute for Medical Research, Montréal, Québec, Canada.,Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, Québec, Canada
| | - Anne Gatignol
- Lady Davis Institute for Medical Research, Montréal, Québec, Canada.,Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, Québec, Canada.,Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada
| | - Robert J Scarborough
- Lady Davis Institute for Medical Research, Montréal, Québec, Canada.,Department of Microbiology and Immunology, McGill University, Montréal, Québec, Canada
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4
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Fan T, Zhao YZ, Yang JF, Liu QL, Tian Y, Debatosh D, Liu YG, Zhang J, Chen C, Chen MX, Zhou SM. Phylogenetic comparison and splice site conservation of eukaryotic U1 snRNP-specific U1-70K gene family. Sci Rep 2021; 11:12760. [PMID: 34140531 PMCID: PMC8211703 DOI: 10.1038/s41598-021-91693-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 05/05/2021] [Indexed: 02/05/2023] Open
Abstract
Eukaryotic cells can expand their coding ability by using their splicing machinery, spliceosome, to process precursor mRNA (pre-mRNA) into mature messenger RNA. The mega-macromolecular spliceosome contains multiple subcomplexes, referred to as small nuclear ribonucleoproteins (snRNPs). Among these, U1 snRNP and its central component, U1-70K, are crucial for splice site recognition during early spliceosome assembly. The human U1-70K has been linked to several types of human autoimmune and neurodegenerative diseases. However, its phylogenetic relationship has been seldom reported. To this end, we carried out a systemic analysis of 95 animal U1-70K genes and compare these proteins to their yeast and plant counterparts. Analysis of their gene and protein structures, expression patterns and splicing conservation suggest that animal U1-70Ks are conserved in their molecular function, and may play essential role in cancers and juvenile development. In particular, animal U1-70Ks display unique characteristics of single copy number and a splicing isoform with truncated C-terminal, suggesting the specific role of these U1-70Ks in animal kingdom. In summary, our results provide phylogenetic overview of U1-70K gene family in vertebrates. In silico analyses conducted in this work will act as a reference for future functional studies of this crucial U1 splicing factor in animal kingdom.
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Affiliation(s)
- Tao Fan
- grid.452787.b0000 0004 1806 5224Division of Gastroenterology, Shenzhen Children’s Hospital, Shenzhen, 518038 People’s Republic of China ,grid.440622.60000 0000 9482 4676State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Taian, Shandong People’s Republic of China ,grid.10784.3a0000 0004 1937 0482Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People’s Republic of China
| | - Yu-Zhen Zhao
- grid.452787.b0000 0004 1806 5224Division of Gastroenterology, Shenzhen Children’s Hospital, Shenzhen, 518038 People’s Republic of China
| | - Jing-Fang Yang
- grid.411407.70000 0004 1760 2614Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan, 430079 People’s Republic of China
| | - Qin-Lai Liu
- School of Basic Medicine, Shandong First Medical University and Shandong Academy of Medical Sciences, Qingdao, People’s Republic of China
| | - Yuan Tian
- grid.440622.60000 0000 9482 4676State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Taian, Shandong People’s Republic of China ,grid.10784.3a0000 0004 1937 0482Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People’s Republic of China
| | - Das Debatosh
- grid.10784.3a0000 0004 1937 0482Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People’s Republic of China
| | - Ying-Gao Liu
- grid.440622.60000 0000 9482 4676State Key Laboratory of Crop Biology, College of Life Science, Shandong Agricultural University, Taian, Shandong People’s Republic of China
| | - Jianhua Zhang
- grid.10784.3a0000 0004 1937 0482Department of Biology, Hong Kong Baptist University, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Chen Chen
- grid.410745.30000 0004 1765 1045Department of Infectious Disease, Nanjing Infectious Disease Center, The Second Hospital of Nanjing, Nanjing University of Chinese Medicine, Nanjing, 210003 People’s Republic of China
| | - Mo-Xian Chen
- grid.452787.b0000 0004 1806 5224Division of Gastroenterology, Shenzhen Children’s Hospital, Shenzhen, 518038 People’s Republic of China
| | - Shao-Ming Zhou
- grid.452787.b0000 0004 1806 5224Division of Gastroenterology, Shenzhen Children’s Hospital, Shenzhen, 518038 People’s Republic of China
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5
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Del Corpo O, Goguen RP, Malard CMG, Daher A, Colby-Germinario S, Scarborough RJ, Gatignol A. A U1i RNA that Enhances HIV-1 RNA Splicing with an Elongated Recognition Domain Is an Optimal Candidate for Combination HIV-1 Gene Therapy. MOLECULAR THERAPY. NUCLEIC ACIDS 2019; 18:815-830. [PMID: 31734561 PMCID: PMC6861678 DOI: 10.1016/j.omtn.2019.10.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/27/2019] [Accepted: 10/12/2019] [Indexed: 11/30/2022]
Abstract
U1 interference (U1i) RNAs can be designed to correct splicing defects and target pathogenic RNA, such as HIV-1 RNA. In this study, we show that U1i RNAs that enhance HIV-1 RNA splicing are more effective at inhibiting HIV-1 production compared to top U1i RNAs that inhibit polyadenylation of HIV-1 RNA. A U1i RNA was also identified targeting a site upstream of the first splice acceptor site in the Gag coding region that was effective at inhibiting HIV-1 production. U1-T6, which enhanced HIV-1 RNA splicing, was superior to an antiviral short hairpin RNA (shRNA) currently in clinical trials. To increase specificity, the recognition domain of U1-T6 was elongated by 3–6 nt. The elongated molecules inhibited HIV-1 production from different HIV-1 strains, including one with a mismatch in the target site. These results suggest that lengthening the recognition domain can enhance the specificity of U1i RNAs for their intended target sites while at the same time allowing them to tolerate single mismatch mutations. Overall, our results demonstrate that U1-T6 with an elongated recognition domain inhibits HIV-1 production and has both the efficacy and specificity to be a promising candidate for HIV-1 gene therapy.
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Affiliation(s)
- Olivier Del Corpo
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC H3A 0G4, Canada
| | - Ryan P Goguen
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 0G4, Canada
| | - Camille M G Malard
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 0G4, Canada
| | - Aïcha Daher
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada
| | | | - Robert J Scarborough
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 0G4, Canada.
| | - Anne Gatignol
- Lady Davis Institute for Medical Research, Montréal, QC H3T 1E2, Canada; Department of Medicine, Division of Experimental Medicine, McGill University, Montréal, QC H3A 0G4, Canada; Department of Microbiology and Immunology, McGill University, Montréal, QC H3A 0G4, Canada.
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6
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Scarborough RJ, Adams KL, Del Corpo O, Daher A, Gatignol A. Evaluation of the Efficacy And Toxicity of RNAs Targeting HIV-1 Production for Use in Gene or Drug Therapy. J Vis Exp 2016. [PMID: 27684275 DOI: 10.3791/54486] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Small RNA therapies targeting post-integration steps in the HIV-1 replication cycle are among the top candidates for gene therapy and have the potential to be used as drug therapies for HIV-1 infection. Post-integration inhibitors include ribozymes, short hairpin (sh) RNAs, small interfering (si) RNAs, U1 interference (U1i) RNAs and RNA aptamers. Many of these have been identified using transient co-transfection assays with an HIV-1 expression plasmid and some have advanced to clinical trials. In addition to measures of efficacy, small RNAs have been evaluated for their potential to affect the expression of human RNAs, alter cell growth and/or differentiation, and elicit innate immune responses. In the protocols described here, a set of transient transfection assays designed to evaluate the efficacy and toxicity of RNA molecules targeting post-integration steps in the HIV-1 replication cycle are described. We have used these assays to identify new ribozymes and optimize the format of shRNAs and siRNAs targeting HIV-1 RNA. The methods provide a quick set of assays that are useful for screening new anti-HIV-1 RNAs and could be adapted to screen other post-integration inhibitors of HIV-1 replication.
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Affiliation(s)
- Robert J Scarborough
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research; Department of Microbiology & Immunology, McGill University
| | - Kelsey L Adams
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research; Department of Microbiology & Immunology, McGill University
| | - Olivier Del Corpo
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research; Department of Microbiology & Immunology, McGill University
| | - Aïcha Daher
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research
| | - Anne Gatignol
- Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research; Department of Microbiology & Immunology, McGill University; Department of Medicine, McGill University;
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7
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Bouton C, Geldreich A, Ramel L, Ryabova LA, Dimitrova M, Keller M. Cauliflower mosaic virus Transcriptome Reveals a Complex Alternative Splicing Pattern. PLoS One 2015; 10:e0132665. [PMID: 26162084 PMCID: PMC4498817 DOI: 10.1371/journal.pone.0132665] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 06/18/2015] [Indexed: 12/23/2022] Open
Abstract
The plant pararetrovirus Cauliflower mosaic virus (CaMV) uses alternative splicing to generate several isoforms from its polycistronic pregenomic 35S RNA. This pro-cess has been shown to be essential for infectivity. Previous works have identified four splice donor sites and a single splice acceptor site in the 35S RNA 5' region and suggested that the main role of CaMV splicing is to downregulate expression of open reading frames (ORFs) I and II. In this study, we show that alternative splicing is a conserved process among CaMV isolates. In Cabb B-JI and Cabb-S isolates, splicing frequently leads to different fusion between ORFs, particularly between ORF I and II. The corresponding P1P2 fusion proteins expressed in E. coli interact with viral proteins P2 and P3 in vitro. However, they are detected neither during infection nor upon transient expression in planta, which suggests rapid degradation after synthesis and no important biological role in the CaMV infectious cycle. To gain a better understanding of the functional relevance of 35S RNA alternative splicing in CaMV infectivity, we inactivated the previously described splice sites. All the splicing mutants were as pathogenic as the corresponding wild-type isolate. Through RT-PCR-based analysis we demonstrate that CaMV 35S RNA exhibits a complex splicing pattern, as we identify new splice donor and acceptor sites whose selection leads to more than thirteen 35S RNA isoforms in infected turnip plants. Inactivating splice donor or acceptor sites is not lethal for the virus, since disrupted sites are systematically rescued by the activation of cryptic and/or seldom used splice sites. Taken together, our data depict a conserved, complex and flexible process, involving multiple sites, that ensures splicing of 35S RNA.
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Affiliation(s)
- Clément Bouton
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Angèle Geldreich
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Laëtitia Ramel
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Lyubov A. Ryabova
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
| | - Maria Dimitrova
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
- * E-mail: (MD); (MK)
| | - Mario Keller
- Institut de Biologie Moléculaire des Plantes du CNRS, Université de Strasbourg, Strasbourg, France
- * E-mail: (MD); (MK)
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8
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Platt C, Calimano M, Nemet J, Bubenik J, Cochrane A. Differential Effects of Tra2ß Isoforms on HIV-1 RNA Processing and Expression. PLoS One 2015; 10:e0125315. [PMID: 25970345 PMCID: PMC4430212 DOI: 10.1371/journal.pone.0125315] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 03/16/2015] [Indexed: 12/03/2022] Open
Abstract
Balanced processing of HIV-1 RNA is critical to virus replication and is regulated by host factors. In this report, we demonstrate that overexpression of either Tra2α or Tra2β results in a marked reduction in HIV-1 Gag/ Env expression, an effect associated with changes in HIV-1 RNA accumulation, altered viral splice site usage, and a block to export of HIV-1 genomic RNA. A natural isoform of Tra2β (Tra2ß3), lacking the N-terminal RS domain, also suppressed HIV-1 expression but had different effects on viral RNA processing. The functional differences between the Tra2β isoforms were also observed in the context of another RNA substrate indicating that these factors have distinct functions within the cell. Finally, we demonstrate that Tra2ß depletion results in a selective reduction in HIV-1 Env expression as well as an increase in multiply spliced viral RNA. Together, the findings indicate that Tra2α/β can play important roles in regulating HIV-1 RNA metabolism and expression.
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MESH Headings
- Gene Expression Regulation
- HEK293 Cells
- HIV-1/genetics
- HIV-1/metabolism
- HeLa Cells
- Host-Pathogen Interactions
- Humans
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Protein Isoforms/antagonists & inhibitors
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA Splice Sites
- RNA Splicing
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/genetics
- RNA, Small Interfering/metabolism
- RNA, Viral/genetics
- RNA, Viral/metabolism
- RNA-Binding Proteins/antagonists & inhibitors
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/metabolism
- Serine-Arginine Splicing Factors
- Signal Transduction
- Virus Replication
- env Gene Products, Human Immunodeficiency Virus/antagonists & inhibitors
- env Gene Products, Human Immunodeficiency Virus/genetics
- env Gene Products, Human Immunodeficiency Virus/metabolism
- gag Gene Products, Human Immunodeficiency Virus/antagonists & inhibitors
- gag Gene Products, Human Immunodeficiency Virus/genetics
- gag Gene Products, Human Immunodeficiency Virus/metabolism
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Affiliation(s)
- Craig Platt
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Maria Calimano
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Josip Nemet
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Jodi Bubenik
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Alan Cochrane
- Dept. of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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Abstract
Ribozymes are structured RNA molecules that act as catalysts in different biological reactions. From simple genome cleaving activities in satellite RNAs to more complex functions in cellular protein synthesis and gene regulation, ribozymes play important roles in all forms of life. Several naturally existing ribozymes have been modified for use as therapeutics in different conditions, with HIV-1 infection being one of the most studied. This chapter summarizes data from different preclinical and clinical studies conducted to evaluate the potential of ribozymes to be used in HIV-1 therapies. The different ribozyme motifs that have been modified, as well as their target sites and expression strategies, are described. RNA conjugations used to enhance the antiviral effect of ribozymes are also presented and the results from clinical trials conducted to date are summarized. Studies on anti-HIV-1 ribozymes have provided valuable information on the optimal expression strategies and clinical protocols for RNA gene therapy and remain competitive candidates for future therapy.
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10
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U1 interference (U1i) for Antiviral Approaches. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 848:51-69. [DOI: 10.1007/978-1-4939-2432-5_3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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11
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Herrera-Carrillo E, Berkhout B. Potential mechanisms for cell-based gene therapy to treat HIV/AIDS. Expert Opin Ther Targets 2014; 19:245-63. [PMID: 25388088 DOI: 10.1517/14728222.2014.980236] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION An estimated 35 million people are infected with HIV worldwide. Anti-retroviral therapy (ART) has reduced the morbidity and mortality of HIV-infected patients but efficacy requires strict adherence and the treatment is not curative. Most importantly, the emergence of drug-resistant virus strains and drug toxicity can restrict the long-term therapeutic efficacy in some patients. Therefore, novel treatment strategies that permanently control or eliminate the virus and restore the damaged immune system are required. Gene therapy against HIV infection has been the topic of intense investigations for the last two decades because it can theoretically provide such a durable anti-HIV control. AREAS COVERED In this review we discuss two major gene therapy strategies to combat HIV. One approach aims to kill HIV-infected cells and the other is based on the protection of cells from HIV infection. We discuss the underlying molecular mechanisms for candidate approaches to permanently block HIV infection, including the latest strategies and future therapeutic applications. EXPERT OPINION Hematopoietic stem cell-based gene therapy for HIV/AIDS may eventually become an alternative for standard ART and should ideally provide a functional cure in which the virus is durably controlled without medication. Recent results from preclinical research and early-stage clinical trials support the feasibility and safety of this novel strategy.
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Affiliation(s)
- Elena Herrera-Carrillo
- Academic Medical Center University of Amsterdam, Department of Medical Microbiology , Meibergdreef 15, Amsterdam, 1105 AZ , The Netherlands
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Scarborough RJ, Lévesque MV, Boudrias-Dalle E, Chute IC, Daniels SM, Ouellette RJ, Perreault JP, Gatignol A. A Conserved Target Site in HIV-1 Gag RNA is Accessible to Inhibition by Both an HDV Ribozyme and a Short Hairpin RNA. MOLECULAR THERAPY. NUCLEIC ACIDS 2014; 3:e178. [PMID: 25072692 PMCID: PMC4121520 DOI: 10.1038/mtna.2014.31] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 06/03/2014] [Indexed: 12/18/2022]
Abstract
Antisense-based molecules targeting HIV-1 RNA have the potential to be used as part of gene or drug therapy to treat HIV-1 infection. In this study, HIV-1 RNA was screened to identify more conserved and accessible target sites for ribozymes based on the hepatitis delta virus motif. Using a quantitative screen for effects on HIV-1 production, we identified a ribozyme targeting a highly conserved site in the Gag coding sequence with improved inhibitory potential compared to our previously described candidates targeting the overlapping Tat/Rev coding sequence. We also demonstrate that this target site is highly accessible to short hairpin directed RNA interference, suggesting that it may be available for the binding of antisense RNAs with different modes of action. We provide evidence that this target site is structurally conserved in diverse viral strains and that it is sufficiently different from the human transcriptome to limit off-target effects from antisense therapies. We also show that the modified hepatitis delta virus ribozyme is more sensitive to a mismatch in its target site compared to the short hairpin RNA. Overall, our results validate the potential of a new target site in HIV-1 RNA to be used for the development of antisense therapies.
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Affiliation(s)
- Robert J Scarborough
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
| | - Michel V Lévesque
- Département de Biochimie, RNA Group/Groupe ARN, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Etienne Boudrias-Dalle
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
| | - Ian C Chute
- Atlantic Cancer Research Institute, Moncton, New Brunswick, Canada
| | - Sylvanne M Daniels
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada
| | | | - Jean-Pierre Perreault
- Département de Biochimie, RNA Group/Groupe ARN, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Anne Gatignol
- 1] Virus-Cell Interactions Laboratory, Lady Davis Institute for Medical Research, Montréal, Québec, Canada [2] Department of Microbiology & Immunology, McGill University, Montréal, Québec, Canada [3] Department of Medicine, McGill University, Montréal, Québec, Canada
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13
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Lu Z, Guan X, Schmidt CA, Matera AG. RIP-seq analysis of eukaryotic Sm proteins identifies three major categories of Sm-containing ribonucleoproteins. Genome Biol 2014; 15:R7. [PMID: 24393626 PMCID: PMC4053861 DOI: 10.1186/gb-2014-15-1-r7] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 01/07/2014] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Sm proteins are multimeric RNA-binding factors, found in all three domains of life. Eukaryotic Sm proteins, together with their associated RNAs, form small ribonucleoprotein (RNP) complexes important in multiple aspects of gene regulation. Comprehensive knowledge of the RNA components of Sm RNPs is critical for understanding their functions. RESULTS We developed a multi-targeting RNA-immunoprecipitation sequencing (RIP-seq) strategy to reliably identify Sm-associated RNAs from Drosophila ovaries and cultured human cells. Using this method, we discovered three major categories of Sm-associated transcripts: small nuclear (sn)RNAs, small Cajal body (sca)RNAs and mRNAs. Additional RIP-PCR analysis showed both ubiquitous and tissue-specific interactions. We provide evidence that the mRNA-Sm interactions are mediated by snRNPs, and that one of the mechanisms of interaction is via base pairing. Moreover, the Sm-associated mRNAs are mature, indicating a splicing-independent function for Sm RNPs. CONCLUSIONS This study represents the first comprehensive analysis of eukaryotic Sm-containing RNPs, and provides a basis for additional functional analyses of Sm proteins and their associated snRNPs outside of the context of pre-mRNA splicing. Our findings expand the repertoire of eukaryotic Sm-containing RNPs and suggest new functions for snRNPs in mRNA metabolism.
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Affiliation(s)
- Zhipeng Lu
- Departments of Biology and Genetics, Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599-3280, USA
| | - Xiaojun Guan
- Center for Bioinformatics, University of North Carolina, Chapel Hill, NC 27599-3280, USA
- Current address: Sequenom, San Diego, CA 92121, USA
| | - Casey A Schmidt
- Curriculum in Genetics & Molecular Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA
| | - A Gregory Matera
- Departments of Biology and Genetics, Integrative Program for Biological and Genome Sciences, University of North Carolina, Chapel Hill, NC 27599-3280, USA
- Curriculum in Genetics & Molecular Biology, University of North Carolina, Chapel Hill, NC 27599-3280, USA
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14
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Putting an 'End' to HIV mRNAs: capping and polyadenylation as potential therapeutic targets. AIDS Res Ther 2013; 10:31. [PMID: 24330569 PMCID: PMC3874655 DOI: 10.1186/1742-6405-10-31] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 11/26/2013] [Indexed: 01/27/2023] Open
Abstract
Like most cellular mRNAs, the 5′ end of HIV mRNAs is capped and the 3′ end matured by the process of polyadenylation. There are, however, several rather unique and interesting aspects of these post-transcriptional processes on HIV transcripts. Capping of the highly structured 5′ end of HIV mRNAs is influenced by the viral TAT protein and a population of HIV mRNAs contains a trimethyl-G cap reminiscent of U snRNAs involved in splicing. HIV polyadenylation involves active repression of a promoter-proximal polyadenylation signal, auxiliary upstream regulatory elements and moonlighting polyadenylation factors that have additional impacts on HIV biology outside of the constraints of classical mRNA 3’ end formation. This review describes these post-transcriptional novelties of HIV gene expression as well as their implications in viral biology and as possible targets for therapeutic intervention.
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15
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Knoepfel SA, Abad A, Abad X, Fortes P, Berkhout B. Design of modified U1i molecules against HIV-1 RNA. Antiviral Res 2012; 94:208-16. [DOI: 10.1016/j.antiviral.2012.03.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 03/21/2012] [Accepted: 03/27/2012] [Indexed: 12/25/2022]
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16
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Koornneef A, van Logtenstein R, Timmermans E, Pisas L, Blits B, Abad X, Fortes P, Petry H, Konstantinova P, Ritsema T. AAV-mediated in vivo knockdown of luciferase using combinatorial RNAi and U1i. Gene Ther 2011; 18:929-35. [PMID: 21472008 PMCID: PMC3169806 DOI: 10.1038/gt.2011.41] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
RNA interference (RNAi) has been successfully employed for specific inhibition of gene expression; however, safety and delivery of RNAi remain critical issues. We investigated the combinatorial use of RNAi and U1 interference (U1i). U1i is a gene-silencing technique that acts on the pre-mRNA by preventing polyadenylation. RNAi and U1i have distinct mechanisms of action in different cellular compartments and their combined effect allows usage of minimal doses, thereby avoiding toxicity while retaining high target inhibition. As a proof of concept, we investigated knockdown of the firefly luciferase reporter gene by combinatorial use of RNAi and U1i, and evaluated their inhibitory potential both in vitro and in vivo. Co-transfection of RNAi and U1i constructs showed additive reduction of luciferase expression up to 95% in vitro. We attained similar knockdown when RNAi and U1i constructs were hydrodynamically transfected into murine liver, demonstrating for the first time successful in vivo application of U1i. Moreover, we demonstrated long-term gene silencing by AAV-mediated transduction of murine muscle with RNAi/U1i constructs targeting firefly luciferase. In conclusion, these results provide a proof of principle for the combinatorial use of RNAi and U1i to enhance target gene knockdown in vivo.
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Affiliation(s)
- A Koornneef
- Department of Research and Development, Amsterdam Molecular Therapeutics, Amsterdam, The Netherlands.
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17
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Excessive RNA splicing and inhibition of HIV-1 replication induced by modified U1 small nuclear RNAs. J Virol 2010; 84:12790-800. [PMID: 20926575 DOI: 10.1128/jvi.01257-10] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
HIV-1 RNA undergoes a complex splicing process whereby over 40 different mRNA species are produced by alternative splicing. In addition, approximately half of the RNA transcripts remain unspliced and either are used to encode Gag and Gag-Pol proteins or are packaged into virions as genomic RNA. It has previously been shown that HIV-1 splicing is regulated by cis elements that bind to cellular factors. These factors either enhance or repress definition of exons that are flanked by the HIV-1 3' splice sites. Here we report that expression of modified U1 snRNPs with increased affinity to HIV-1 downstream 5' splice sites and to sequences within the first tat coding exon act to selectively increase splicing at the upstream 3' splice sites in cotransfected 293T cells. This results in a decrease of unspliced viral RNA levels and an approximately 10-fold decrease in virus production. In addition, excessive splicing of viral RNA is concomitant with a striking reduction in the relative amounts of Gag processing intermediates and products. We also show that T cell lines expressing modified U1 snRNAs exhibit reduced HIV-1 replication. Our results suggest that induction of excessive HIV-1 RNA splicing may be a novel strategy to inhibit virus replication in human patients.
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18
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Abad X, Razquin N, Abad A, Fortes P. Combination of RNA interference and U1 inhibition leads to increased inhibition of gene expression. Nucleic Acids Res 2010; 38:e136. [PMID: 20427423 PMCID: PMC2910067 DOI: 10.1093/nar/gkq299] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RNA interference (RNAi) has been revolutionary for the specific inhibition of gene expression. However, the application of RNAi has been hampered by the fact that many siRNAs induce dose-dependent unwanted secondary effects. Therefore, new methods to increase inhibition of gene expression with low doses of inhibitors are required. We have tested the combination of RNAi and U1i (U1 small nuclear RNA—snRNA—interference). U1i is based on U1 inhibitors (U1in), U1 snRNA molecules modified to target a pre-mRNA and inhibit its gene expression by blocking nuclear polyadenylation. The combination of RNAi and U1i resulted in stronger inhibition of reporter or endogenous genes than that obtained using either of the techniques alone. The increased inhibition observed is stable over time and allows higher inhibition than the best obtained with either of the inhibitors alone even with decreased doses of the inhibitors. We believe that the combination of RNAi and U1i will be of interest when higher inhibition is required or when potent inhibitors are not available. Also, the combination of these techniques would allow functional inhibition with a decreased dose of inhibitors, avoiding toxicity due to dose-dependent unwanted effects.
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Affiliation(s)
- X Abad
- Department of Hepatology and Gene Therapy, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona 31008, Spain
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19
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Jankowska A, Gunderson SI, Andrusiewicz M, Burczynska B, Szczerba A, Jarmolowski A, Nowak-Markwitz E, Warchol JB. Reduction of human chorionic gonadotropin beta subunit expression by modified U1 snRNA caused apoptosis in cervical cancer cells. Mol Cancer 2008; 7:26. [PMID: 18339208 PMCID: PMC2335103 DOI: 10.1186/1476-4598-7-26] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Accepted: 03/14/2008] [Indexed: 11/10/2022] Open
Abstract
Background Secretion of human chorionic gonadotropin, especially its beta subunit by malignant trophoblastic tumors and varieties of tumors of different origin is now well documented; however the role of hCG in tumorogenesis is still unknown. Results This study documents the molecular presence of human chorionic gonadotropin beta subunit in uterine cervix cancer tissues and investigates a novel technique to reduce hCGβ levels based on expression of a modified U1 snRNA as a method to study the hormone's role in biology of human cervical cancer cells cultured in vitro. The property of U1 snRNA to block the accumulation of specific RNA transcript when it binds to its donor sequence within the 3' terminal exon was used. The first 10 nucleotides of the human U1 snRNA gene, which normally binds to the 5'ss in pre-mRNA were replaced by a sequence complementary to a 10-nt segment in the terminal exon of the hCGβ mRNA. Three different 5' end-mutated U1 snRNA expression plasmids were tested, each targeting a different sequence in the hCGβ mRNA, and we found each one blocked the expression of hCGβ in HeLa cells, a cervix carcinoma cell line, as shown by immunohistochemistry and qRT-PCR. Reduction of hCGβ levels resulted in a significantly increased apoptosis rate with almost 90% of cells transfected with modified anti-hCGβ U1 snRNAs showing morphological changes characteristic of the apoptotic process. Conclusion These data suggest that human chorionic gonadotropin beta subunit may act as a tumor growth-stimulating factor.
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Affiliation(s)
- Anna Jankowska
- Department of Cell Biology, University of Medical Sciences, Rokietnicka 5D, Poznan, Poland.
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20
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Abad X, Vera M, Jung SP, Oswald E, Romero I, Amin V, Fortes P, Gunderson SI. Requirements for gene silencing mediated by U1 snRNA binding to a target sequence. Nucleic Acids Res 2008; 36:2338-52. [PMID: 18299285 PMCID: PMC2367729 DOI: 10.1093/nar/gkn068] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
U1 interference (U1i) is a novel method to block gene expression. U1i requires expression of a 5'-end-mutated U1 snRNA designed to base pair to the 3'-terminal exon of the target gene's pre-mRNA that leads to inhibition of polyadenylation. Here, we show U1i is robust (> or =95%) and a 10-nt target length is sufficient for good silencing. Surprisingly, longer U1 snRNAs, which could increase annealing to the target, fail to improve silencing. Extensive mutagenesis of the 10-bp U1 snRNA:target duplex shows that any single mismatch different from GU at positions 3-8, destroys silencing. However, mismatches within the other positions give partial silencing, suggesting that off-target inhibition could occur. The specificity of U1i may be enhanced, however, by the fact that silencing is impaired by RNA secondary structure or by splicing factors binding nearby, the latter mediated by Arginine-Serine (RS) domains. U1i inhibition can be reconstituted in vivo by tethering of RS domains of U1-70K and U2AF65. These results help to: (i) define good target sites for U1i; (ii) identify and understand natural cellular examples of U1i; (iii) clarify the contribution of hydrogen bonding to U1i and to U1 snRNP binding to 5' splice sites and (iv) understand the mechanism of U1i.
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Affiliation(s)
- Xabi Abad
- Division of Hepatology and Gene Therapy, CIMA/UNAV. Pio XII, 55, 31008 Pamplona, Spain
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21
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Guan F, Caratozzolo RM, Goraczniak R, Ho ES, Gunderson SI. A bipartite U1 site represses U1A expression by synergizing with PIE to inhibit nuclear polyadenylation. RNA (NEW YORK, N.Y.) 2007; 13:2129-40. [PMID: 17942741 PMCID: PMC2080603 DOI: 10.1261/rna.756707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
U1A protein negatively autoregulates itself by polyadenylation inhibition of its own pre-mRNA by binding as two molecules to a 3'UTR-located Polyadenylation Inhibitory Element (PIE). The (U1A)2-PIE complex specifically blocks U1A mRNA biosynthesis by inhibiting polyA tail addition, leading to lower mRNA levels. U1 snRNP bound to a 5'ss-like sequence, which we call a U1 site, in the 3'UTRs of certain papillomaviruses leads to inhibition of viral late gene expression via a similar mechanism. Although such U1 sites can also be artificially used to potently silence reporter and endogenous genes, no naturally occurring U1 sites have been found in eukaryotic genes. Here we identify a conserved U1 site in the human U1A gene that is, unexpectedly, within a bipartite element where the other part represses the U1 site via a base-pairing mechanism. The bipartite element inhibits U1A expression via a synergistic action with the nearby PIE. Unexpectedly, synergy is not based on stabilizing binding of the inhibitory factors to the 3'UTR, but rather is a property of the larger ternary complex. Inhibition targets the biosynthetic step of polyA tail addition rather than altering mRNA stability. This is the first example of a functional U1 site in a cellular gene and of a single gene containing two dissimilar elements that inhibit nuclear polyadenylation. Parallels with other examples where U1 snRNP inhibits expression are discussed. We expect that other cellular genes will harbor functional U1 sites.
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Affiliation(s)
- Fei Guan
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, New Jersey 08854, USA
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22
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Scherer L, Rossi JJ, Weinberg MS. Progress and prospects: RNA-based therapies for treatment of HIV infection. Gene Ther 2007; 14:1057-64. [PMID: 17607313 DOI: 10.1038/sj.gt.3302977] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The current treatment regimen for HIV-infected individuals combines two or more drugs targeting different viral proteins such as RT and gag. Resistance to conventional drugs can develop quickly, and typically persists. The prospect of longer, continuous antiretroviral therapy brings with it the need for new antiretroviral drugs and approaches. In this context, gene therapies have the potential to prolong life and quality of life as an additional therapeutic class and may serve as an adjuvant to traditional treatments. This review focuses on RNA-based hematopoietic cell gene therapy for treatment of HIV infection. Recent advances in our understanding of RNA interference (RNAi) make this an especially attractive candidate for anti-HIV gene therapy although ribozyme and RNA decoy/aptamer approaches can be combined with RNAi to make a combinatorial therapy akin to highly active anti-retroviral therapy.
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Affiliation(s)
- L Scherer
- Division of Molecular Biology, City of Hope Beckman Research Institute, Duarte, CA 91010, USA
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