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Roesmann F, Müller L, Klaassen K, Heß S, Widera M. Interferon-Regulated Expression of Cellular Splicing Factors Modulates Multiple Levels of HIV-1 Gene Expression and Replication. Viruses 2024; 16:938. [PMID: 38932230 PMCID: PMC11209495 DOI: 10.3390/v16060938] [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: 04/30/2024] [Revised: 05/31/2024] [Accepted: 06/03/2024] [Indexed: 06/28/2024] Open
Abstract
Type I interferons (IFN-Is) are pivotal in innate immunity against human immunodeficiency virus I (HIV-1) by eliciting the expression of IFN-stimulated genes (ISGs), which encompass potent host restriction factors. While ISGs restrict the viral replication within the host cell by targeting various stages of the viral life cycle, the lesser-known IFN-repressed genes (IRepGs), including RNA-binding proteins (RBPs), affect the viral replication by altering the expression of the host dependency factors that are essential for efficient HIV-1 gene expression. Both the host restriction and dependency factors determine the viral replication efficiency; however, the understanding of the IRepGs implicated in HIV-1 infection remains greatly limited at present. This review provides a comprehensive overview of the current understanding regarding the impact of the RNA-binding protein families, specifically the two families of splicing-associated proteins SRSF and hnRNP, on HIV-1 gene expression and viral replication. Since the recent findings show specifically that SRSF1 and hnRNP A0 are regulated by IFN-I in various cell lines and primary cells, including intestinal lamina propria mononuclear cells (LPMCs) and peripheral blood mononuclear cells (PBMCs), we particularly discuss their role in the context of the innate immunity affecting HIV-1 replication.
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Affiliation(s)
- Fabian Roesmann
- Institute for Medical Virology, University Hospital Frankfurt, Goethe University Frankfurt, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
| | - Lisa Müller
- Institute of Virology, Medical Faculty, University Hospital Düsseldorf, Heinrich-Heine-University Düsseldorf, Universitätsstr. 1, 40225 Düsseldorf, Germany
| | - Katleen Klaassen
- Institute for Medical Virology, University Hospital Frankfurt, Goethe University Frankfurt, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
| | - Stefanie Heß
- Institute for Medical Virology, University Hospital Frankfurt, Goethe University Frankfurt, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
| | - Marek Widera
- Institute for Medical Virology, University Hospital Frankfurt, Goethe University Frankfurt, Paul-Ehrlich-Str. 40, 60596 Frankfurt am Main, Germany
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2
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Moreira L, Guimarães NM, Santos RS, Loureiro JA, Pereira MC, Azevedo NF. Promising strategies employing nucleic acids as antimicrobial drugs. MOLECULAR THERAPY. NUCLEIC ACIDS 2024; 35:102122. [PMID: 38333674 PMCID: PMC10850860 DOI: 10.1016/j.omtn.2024.102122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
Abstract
Antimicrobial resistance (AMR) is a growing concern because it causes microorganisms to develop resistance to drugs commonly used to treat infections. This results in increased difficulty in treating infections, leading to higher mortality rates and significant economic effects. Investing in new antimicrobial agents is, therefore, necessary to prevent and control AMR. Antimicrobial nucleic acids have arisen as potential key players in novel therapies for AMR infections. They have been designed to serve as antimicrobials and to act as adjuvants to conventional antibiotics or to inhibit virulent mechanisms. This new category of antimicrobial drugs consists of antisense oligonucleotides and oligomers, DNAzymes, and transcription factor decoys, differing in terms of structure, target molecules, and mechanisms of action. They are synthesized using nucleic acid analogs to enhance their resistance to nucleases. Because bacterial envelopes are generally impermeable to oligonucleotides, delivery into the cytoplasm typically requires the assistance of nanocarriers, which can affect their therapeutic potency. Given that numerous factors contribute to the success of these antimicrobial drugs, this review aims to provide a summary of the key advancements in the use of oligonucleotides for treating bacterial infections. Their mechanisms of action and the impact of factors such as nucleic acid design, target sequence, and nanocarriers on the antimicrobial potency are discussed.
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Affiliation(s)
- Luís Moreira
- LEPABE–Laboratory for Process Engineering, Environment, Biotechnology, and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE–Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Nuno M. Guimarães
- LEPABE–Laboratory for Process Engineering, Environment, Biotechnology, and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE–Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Rita S. Santos
- LEPABE–Laboratory for Process Engineering, Environment, Biotechnology, and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE–Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Joana A. Loureiro
- LEPABE–Laboratory for Process Engineering, Environment, Biotechnology, and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE–Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Maria C. Pereira
- LEPABE–Laboratory for Process Engineering, Environment, Biotechnology, and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE–Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Nuno F. Azevedo
- LEPABE–Laboratory for Process Engineering, Environment, Biotechnology, and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
- ALiCE–Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Cieślak M, Karwowski BT. The Effect of 8,5'-Cyclo 2'-deoxyadenosine on the Activity of 10-23 DNAzyme: Experimental and Theoretical Study. Int J Mol Sci 2024; 25:2519. [PMID: 38473767 DOI: 10.3390/ijms25052519] [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: 01/24/2024] [Revised: 02/16/2024] [Accepted: 02/19/2024] [Indexed: 03/14/2024] Open
Abstract
The in vivo effectiveness of DNAzymes 10-23 (Dz10-23) is limited due to the low concentration of divalent cations. Modifications of the catalytic loop are being sought to increase the activity of Dz10-23 in physiological conditions. We investigated the effect of 5'S or 5'R 5',8-cyclo-2'deoxyadenosine (cdA) on the activity of Dz10-23. The activity of Dz10-23 was measured in a cleavage assay using radiolabeled RNA. The Density Functional Tight Binding methodology with the self-consistent redistribution of Mulliken charge modification was used to explain different activities of DNAzymes. The substitution of 2'-deoxyadenosine with cdA in the catalytic loop decreased the activity of DNAzymes. Inhibition was dependent on the position of cdA and its absolute configuration. The order of activity of DNAzymes was as follows: wt-Dz > ScdA5-Dz ≈ RcdA15-Dz ≈ ScdA15-Dz > RcdA5-Dz. Theoretical studies revealed that the distance between phosphate groups at position 5 in RcdA5-Dz was significantly increased compared to wt-Dz, while the distance between O4 of dT4 and nonbonding oxygen of PO2 attached to 3'O of dG2 was much shorter. The strong inhibitory effect of RcdA5 may result from hampering the flexibility of the catalytic loop (increased rigidity), which is required for the proper positioning of Me2+ and optimal activity.
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Affiliation(s)
- Marcin Cieślak
- Food Science Department, Faculty of Pharmacy, Medical University of Lodz, ul. Muszynskiego 1, 90-151 Lodz, Poland
| | - Bolesław T Karwowski
- Food Science Department, Faculty of Pharmacy, Medical University of Lodz, ul. Muszynskiego 1, 90-151 Lodz, Poland
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Engelbeen S, O'Reilly D, Van De Vijver D, Verhaart I, van Putten M, Hariharan V, Hassler M, Khvorova A, Damha MJ, Aartsma-Rus A. Challenges of Assessing Exon 53 Skipping of the Human DMD Transcript with Locked Nucleic Acid-Modified Antisense Oligonucleotides in a Mouse Model for Duchenne Muscular Dystrophy. Nucleic Acid Ther 2023; 33:348-360. [PMID: 38010230 PMCID: PMC10698779 DOI: 10.1089/nat.2023.0038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/11/2023] [Indexed: 11/29/2023] Open
Abstract
Antisense oligonucleotide (AON)-mediated exon skipping is a promising therapeutic approach for Duchenne muscular dystrophy (DMD) patients to restore dystrophin expression by reframing the disrupted open reading frame of the DMD transcript. However, the treatment efficacy of the already conditionally approved AONs remains low. Aiming to optimize AON efficiency, we assessed exon 53 skipping of the DMD transcript with different chemically modified AONs, all with a phosphorothioate backbone: 2'-O-methyl (2'OMe), locked nucleic acid (LNA)-2'OMe, 2'-fluoro (FRNA), LNA-FRNA, αLNA-FRNA, and FANA-LNA-FRNA. Efficient exon 53 skipping was observed with the FRNA, LNA-FRNA, and LNA-2'OMe AONs in human control myoblast cultures. Weekly subcutaneous injections (50 mg/kg AON) for a duration of 6 weeks were well tolerated by hDMDdel52/mdx males. Treatment with the LNA-FRNA and LNA-2'OMe AONs resulted in pronounced exon 53 skip levels in skeletal muscles and heart up to 90%, but no dystrophin restoration was observed. This discrepancy was mainly ascribed to the strong binding nature of LNA modifications to RNA, thereby interfering with the amplification of the unskipped product resulting in artificial overamplification of the exon 53 skip product. Our study highlights that treatment effect on RNA and protein level should both be considered when assessing AON efficiency.
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Affiliation(s)
- Sarah Engelbeen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Daniel O'Reilly
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
- Department of Chemistry, McGill University, Montreal, Canada
| | - Davy Van De Vijver
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Ingrid Verhaart
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Maaike van Putten
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Vignesh Hariharan
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
| | - Matthew Hassler
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
| | - Anastasia Khvorova
- University of Massachusetts Chan Medical School, RNA Therapeutics Institute, Worcester, Massachusetts, USA
| | - Masad J. Damha
- Department of Chemistry, McGill University, Montreal, Canada
| | - Annemieke Aartsma-Rus
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
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Xiao L, Zhao Y, Yang M, Luan G, Du T, Deng S, Jia X. A promising nucleic acid therapy drug: DNAzymes and its delivery system. Front Mol Biosci 2023; 10:1270101. [PMID: 37753371 PMCID: PMC10518456 DOI: 10.3389/fmolb.2023.1270101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 08/29/2023] [Indexed: 09/28/2023] Open
Abstract
Based on the development of nucleic acid therapeutic drugs, DNAzymes obtained through in vitro selection technology in 1994 are gradually being sought. DNAzymes are single-stranded DNA molecules with catalytic function, which specifically cleave RNA under the action of metal ions. Various in vivo and in vitro models have recently demonstrated that DNAzymes can target related genes in cancer, cardiovascular disease, bacterial and viral infection, and central nervous system disease. Compared with other nucleic acid therapy drugs, DNAzymes have gained more attention due to their excellent cutting efficiency, high stability, and low cost. Here, We first briefly reviewed the development and characteristics of DNAzymes, then discussed disease-targeting inhibition model of DNAzymes, hoping to provide new insights and ways for disease treatment. Finally, DNAzymes were still subject to some restrictions in practical applications, including low cell uptake efficiency, nuclease degradation and interference from other biological matrices. We discussed the latest delivery strategy of DNAzymes, among which lipid nanoparticles have recently received widespread attention due to the successful delivery of the COVID-19 mRNA vaccine, which provides the possibility for the subsequent clinical application of DNAzymes. In addition, the future development of DNAzymes was prospected.
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Affiliation(s)
- Lang Xiao
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, Sichuan, China
- Sichuan Key Laboratory of Noncoding RNA and Drugs, Chengdu Medical College, Chengdu, Sichuan, China
| | - Yan Zhao
- Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Meng Yang
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, Sichuan, China
- Sichuan Key Laboratory of Noncoding RNA and Drugs, Chengdu Medical College, Chengdu, Sichuan, China
| | - Guangxin Luan
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, Sichuan, China
- Sichuan Key Laboratory of Noncoding RNA and Drugs, Chengdu Medical College, Chengdu, Sichuan, China
| | - Ting Du
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, Sichuan, China
- Sichuan Key Laboratory of Noncoding RNA and Drugs, Chengdu Medical College, Chengdu, Sichuan, China
| | - Shanshan Deng
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, Sichuan, China
- Sichuan Key Laboratory of Noncoding RNA and Drugs, Chengdu Medical College, Chengdu, Sichuan, China
| | - Xu Jia
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, Sichuan, China
- Sichuan Key Laboratory of Noncoding RNA and Drugs, Chengdu Medical College, Chengdu, Sichuan, China
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Tekintaş Y, Temel A. Antisense oligonucleotides: a promising therapeutic option against infectious diseases. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2023; 43:1-39. [PMID: 37395450 DOI: 10.1080/15257770.2023.2228841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 06/19/2023] [Indexed: 07/04/2023]
Abstract
Infectious diseases have been one of the biggest health problems of humanity for centuries. Nucleic acid-based therapeutics have received attention in recent years with their effectiveness in the treatment of various infectious diseases and vaccine development studies. This review aims to provide a comprehensive understanding of the basic properties underlying the mechanism of antisense oligonucleotides (ASOs), their applications, and their challenges. The efficient delivery of ASOs is the greatest challenge for their therapeutic success, but this problem is overcome with new-generation antisense molecules developed with chemical modifications. The types, carrier molecules, and gene regions targeted by sequences have been summarized in detail. Research and development of antisense therapy is still in its infancy; however, gene silencing therapies appear to have the potential for faster and longer-lasting activity than conventional treatment strategies. On the other hand, realizing the potential of antisense therapy will require a large initial economic investment to ascertain the pharmacological properties and learn how to optimize them. The ability of ASOs to be rapidly designed and synthesized to target different microbes can reduce drug discovery time from 6 years to 1 year. Since ASOs are not particularly affected by resistance mechanisms, they come to the fore in the fight against antimicrobial resistance. The design-based flexibility of ASOs has enabled it to be used for different types of microorganisms/genes and successful in vitro and in vivo results have been revealed. The current review summarized a comprehensive understanding of ASO therapy in combating bacterial and viral infections.
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Affiliation(s)
- Yamaç Tekintaş
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Izmir Katip Celebi University, Izmir, Türkiye
| | - Aybala Temel
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Izmir Katip Celebi University, Izmir, Türkiye
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Gerber PP, Donde MJ, Matheson NJ, Taylor AI. XNAzymes targeting the SARS-CoV-2 genome inhibit viral infection. Nat Commun 2022; 13:6716. [PMID: 36385143 PMCID: PMC9668987 DOI: 10.1038/s41467-022-34339-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022] Open
Abstract
The unprecedented emergence and spread of SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic, underscores the need for diagnostic and therapeutic technologies that can be rapidly tailored to novel threats. Here, we show that site-specific RNA endonuclease XNAzymes - artificial catalysts composed of single-stranded synthetic xeno-nucleic acid oligonucleotides (in this case 2'-deoxy-2'-fluoro-β-D-arabino nucleic acid) - may be designed, synthesised and screened within days, enabling the discovery of a range of enzymes targeting SARS-CoV-2 ORF1ab, ORF7b, spike- and nucleocapsid-encoding RNA. Three of these are further engineered to self-assemble into a catalytic nanostructure with enhanced biostability. This XNA nanostructure is capable of cleaving genomic SARS-CoV-2 RNA under physiological conditions, and when transfected into cells inhibits infection with authentic SARS-CoV-2 virus by RNA knockdown. These results demonstrate the potential of XNAzymes to provide a platform for the rapid generation of antiviral reagents.
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Affiliation(s)
- Pehuén Pereyra Gerber
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK
| | - Maria J Donde
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK
| | - Nicholas J Matheson
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
- NHS Blood and Transplant, Cambridge, UK
| | - Alexander I Taylor
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID), Jeffrey Cheah Biomedical Centre, University of Cambridge, Cambridge, UK.
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8
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Dhorne-Pollet S, Fitzpatrick C, Da Costa B, Bourgon C, Eléouët JF, Meunier N, Burzio VA, Delmas B, Barrey E. Antisense oligonucleotides targeting ORF1b block replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Front Microbiol 2022; 13:915202. [PMID: 36386681 PMCID: PMC9644129 DOI: 10.3389/fmicb.2022.915202] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 09/29/2022] [Indexed: 10/15/2023] Open
Abstract
The ongoing COVID-19 pandemic continues to pose a need for new and efficient therapeutic strategies. We explored antisense therapy using oligonucleotides targeting the severe acute respiratory syndrome coronavirus (SARS-CoV-2) genome. We predicted in silico four antisense oligonucleotides (ASO gapmers with 100% PTO linkages and LNA modifications at their 5' and 3'ends) targeting viral regions ORF1a, ORF1b, N and the 5'UTR of the SARS-CoV-2 genome. Efficiency of ASOs was tested by transfection in human ACE2-expressing HEK-293T cells and monkey VeroE6/TMPRSS2 cells infected with SARS-CoV-2. The ORF1b-targeting ASO was the most efficient, with a 71% reduction in the number of viral genome copies. N- and 5'UTR-targeting ASOs also significantly reduced viral replication by 55 and 63%, respectively, compared to non-related control ASO (ASO-C). Viral titration revealed a significant decrease in SARS-CoV-2 multiplication both in culture media and in cells. These results show that anti-ORF1b ASO can specifically reduce SARS-CoV-2 genome replication in vitro in two different cell infection models. The present study presents proof-of concept of antisense oligonucleotide technology as a promising therapeutic strategy for COVID-19.
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Affiliation(s)
| | - Christopher Fitzpatrick
- INRAE, AgroParisTech, GABI, Université Paris-Saclay, Jouy-en-Josas, France
- Universidad Andrés Bello, Santiago, Chile
| | - Bruno Da Costa
- INRAE, UMR VIM, Université Paris-Saclay, Jouy-en-Josas, France
| | - Clara Bourgon
- INRAE, UMR VIM, Université Paris-Saclay, Jouy-en-Josas, France
| | | | - Nicolas Meunier
- INRAE, UMR VIM, Université Paris-Saclay, Jouy-en-Josas, France
| | - Verónica A. Burzio
- Universidad Andrés Bello, Santiago, Chile
- Centro Científico y Tecnológico de Excelencia Ciencia, Vida/Andes Biotechnologies SpA, Santiago, Chile
| | - Bernard Delmas
- INRAE, UMR VIM, Université Paris-Saclay, Jouy-en-Josas, France
| | - Eric Barrey
- INRAE, AgroParisTech, GABI, Université Paris-Saclay, Jouy-en-Josas, France
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Borggräfe J, Etzkorn M. Solution NMR Spectroscopy as a Tool to Study DNAzyme Structure and Function. Methods Mol Biol 2022; 2439:131-151. [PMID: 35226320 DOI: 10.1007/978-1-0716-2047-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Catalytically active DNA oligomers (or DNAzymes) offer a broad spectrum of functions as well as applications. Although known for over two decades, the DNAzyme's mode-of-actions are still poorly understood, mainly due to lack of high-resolution structural insights. Due to their molecular size, structural flexibility, and dynamic interactions with metal-ion cofactors, solution nuclear magnetic resonance spectroscopy (NMR) can serve as optimal tool to obtain mechanistic insights of DNAzymes. In this respect, nearly all states of the DNAzyme and its substrate during the catalytic cycle are accessible. The instructions and protocols provided in the following may assist the initial steps of an NMR-based characterization of DNAzymes. To reduce the initial setup requirements and foster exciting new research projects, the discussed approaches focus on experiments that do not require cost-intensive isotope labeling strategies.
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Affiliation(s)
- Jan Borggräfe
- Institute of Physical Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Institute of Biological Information Processing, IBI-7: Structural Biochemistry, Forschungszentrum Jülich, Jülich, Germany
| | - Manuel Etzkorn
- Institute of Physical Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
- Institute of Biological Information Processing, IBI-7: Structural Biochemistry, Forschungszentrum Jülich, Jülich, Germany.
- Jülich Center for Structural Biology (JuStruct), Forschungszentrum Jülich, Jülich, Germany.
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10
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Perrin D, Paul S, Wong AAWL, Liu LT. Selection of M2+-independent RNA-cleaving DNAzymes with Sidechains Mimicking Arginine and Lysine. Chembiochem 2021; 23:e202100600. [PMID: 34881502 DOI: 10.1002/cbic.202100600] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 12/04/2021] [Indexed: 11/07/2022]
Abstract
Sequence-specific cleavage of RNA by nucleic acid catalysts in the absence of a divalent metal cation (M 2+ ) has remained an important goal in biomimicry with potential therapeutic applications. Given the lack of functional group diversity in canonical nucleotides, modified nucleotides with amino acid-like side chains were used to enhance self-cleavage rates at a single embedded ribonucleoside site. Previous works relied on three functional groups: an amine, a guanidine and an imidazole ensconced on three different nucleosides. However, to date, few studies have systematically addressed the necessity of all three modifications, as the value of any single modified nucleoside is contextualized at the outset of selection. Herein, we report on the use of only two modified dNTPs, excluding an imidazole, i.e. 5-(3-guanidinoallyl)-2'-dUTP (dU ga TP) and 5-aminoallyl-2'-dCTP (dC aa TP), to select in-vitro self-cleaving DNAzymes that cleave in the absence of M 2+ in a pH-independent fashion. Cleavage shows biphasic kinetics with rate constants that are significantly higher than in unmodified DNAzymes and compare favorably to certain DNAzymes involving an imidazole. This work is the first report of a M2+-independent DNAzyme with two cationic modifications; as such it shows appreciable self-cleaving activity in the absence of an imidazole modification.
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Affiliation(s)
- David Perrin
- U. British Columbia, Chemistry, 2036 Main Mall, V6T-1Z1, Vancouver, CANADA
| | - Somdeb Paul
- The University of British Columbia, Chemistry, 2036 Main Mall, Vancouver, V6T1Z1, Vancouver, CANADA
| | - Antonio A W L Wong
- The University of British Columbia, Chemistry, 2036 Main Mall, Vancouver, V6T1Z1, Vancouver, CANADA
| | - Leo T Liu
- The University of British Columbia, Chemistry, 2036 Main Mall, UBC, Vancouver, V6T-1Z1, Vancouver, CANADA
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Ferreira I, Slott S, Astakhova K, Weber G. Complete Mesoscopic Parameterization of Single LNA Modifications in DNA Applied to Oncogene Probe Design. J Chem Inf Model 2021; 61:3615-3624. [PMID: 34251211 DOI: 10.1021/acs.jcim.1c00470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The use of mesoscopic models to describe the thermodynamic properties of locked nucleic acid (LNA)-modified nucleotides can provide useful insights into their properties, such as hydrogen-bonding and stacking interactions. In addition, the mesoscopic parameters can be used to optimize LNA insertion in probes, to achieve accurate melting temperature predictions, and to obtain duplex opening profiles at the base-pair level. Here, we applied this type of model to parameterize a large set of melting temperatures for LNA-modified sequences, from published sources, covering all possible nearest-neighbor configurations. We have found a very large increase in Morse potentials, which indicates very strong hydrogen bonding as the main cause of improved LNA thermodynamic stability. LNA-modified adenine-thymine (AT) was found to have similar hydrogen bonding to unmodified cytosine-guanine (CG) base pairs, while for LNA CG, we found exceptionally large hydrogen bonding. In contrast, stacking interactions, which were thought to be behind the stability of LNA, were similar to unmodified DNA in most cases. We applied the new LNA parameters to the design of BRAF, KRAS, and EGFR oncogene variants by testing all possible LNA modifications. Selected sequences were then synthesized and had their hybridization temperatures measured, achieving a prediction accuracy within 1 °C. We performed a detailed base-pair opening analysis to discuss specific aspects of these probe hybridizations that may be relevant for probe design.
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Affiliation(s)
- Izabela Ferreira
- Departamento de Física, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.,Programa Interunidades de Pós-Graduação em Bioinformática, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
| | - Sofie Slott
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Bygning 207, 2800 Kgs. Lyngby, Denmark
| | - Kira Astakhova
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Bygning 207, 2800 Kgs. Lyngby, Denmark
| | - Gerald Weber
- Departamento de Física, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
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Wang Y, Nguyen K, Spitale RC, Chaput JC. A biologically stable DNAzyme that efficiently silences gene expression in cells. Nat Chem 2021; 13:319-326. [DOI: 10.1038/s41557-021-00645-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 01/26/2021] [Indexed: 11/09/2022]
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13
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Zhang K, Zheludev IN, Hagey RJ, Wu MTP, Haslecker R, Hou YJ, Kretsch R, Pintilie GD, Rangan R, Kladwang W, Li S, Pham EA, Bernardin-Souibgui C, Baric RS, Sheahan TP, D Souza V, Glenn JS, Chiu W, Das R. Cryo-electron Microscopy and Exploratory Antisense Targeting of the 28-kDa Frameshift Stimulation Element from the SARS-CoV-2 RNA Genome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020. [PMID: 32743589 DOI: 10.1101/2020.07.18.209270] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Drug discovery campaigns against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) are beginning to target the viral RNA genome 1, 2 . The frameshift stimulation element (FSE) of the SARS-CoV-2 genome is required for balanced expression of essential viral proteins and is highly conserved, making it a potential candidate for antiviral targeting by small molecules and oligonucleotides 3-6 . To aid global efforts focusing on SARS-CoV-2 frameshifting, we report exploratory results from frameshifting and cellular replication experiments with locked nucleic acid (LNA) antisense oligonucleotides (ASOs), which support the FSE as a therapeutic target but highlight difficulties in achieving strong inactivation. To understand current limitations, we applied cryogenic electron microscopy (cryo-EM) and the Ribosolve 7 pipeline to determine a three-dimensional structure of the SARS-CoV-2 FSE, validated through an RNA nanostructure tagging method. This is the smallest macromolecule (88 nt; 28 kDa) resolved by single-particle cryo-EM at subnanometer resolution to date. The tertiary structure model, defined to an estimated accuracy of 5.9 Å, presents a topologically complex fold in which the 5' end threads through a ring formed inside a three-stem pseudoknot. Our results suggest an updated model for SARS-CoV-2 frameshifting as well as binding sites that may be targeted by next generation ASOs and small molecules.
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14
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Rosenbach H, Victor J, Etzkorn M, Steger G, Riesner D, Span I. Molecular Features and Metal Ions That Influence 10-23 DNAzyme Activity. Molecules 2020; 25:E3100. [PMID: 32646019 PMCID: PMC7412337 DOI: 10.3390/molecules25133100] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/25/2020] [Accepted: 07/03/2020] [Indexed: 12/17/2022] Open
Abstract
Deoxyribozymes (DNAzymes) with RNA hydrolysis activity have a tremendous potential as gene suppression agents for therapeutic applications. The most extensively studied representative is the 10-23 DNAzyme consisting of a catalytic loop and two substrate binding arms that can be designed to bind and cleave the RNA sequence of interest. The RNA substrate is cleaved between central purine and pyrimidine nucleotides. The activity of this DNAzyme in vitro is considerably higher than in vivo, which was suggested to be related to its divalent cation dependency. Understanding the mechanism of DNAzyme catalysis is hindered by the absence of structural information. Numerous biological studies, however, provide comprehensive insights into the role of particular deoxynucleotides and functional groups in DNAzymes. Here we provide an overview of the thermodynamic properties, the impact of nucleobase modifications within the catalytic loop, and the role of different metal ions in catalysis. We point out features that will be helpful in developing novel strategies for structure determination and to understand the mechanism of the 10-23 DNAzyme. Consideration of these features will enable to develop improved strategies for structure determination and to understand the mechanism of the 10-23 DNAzyme. These insights provide the basis for improving activity in cells and pave the way for developing DNAzyme applications.
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Affiliation(s)
- Hannah Rosenbach
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Julian Victor
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Manuel Etzkorn
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, Wilhelm-Johnen-Straße, 52428 Jülich, Germany
| | - Gerhard Steger
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Detlev Riesner
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
| | - Ingrid Span
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (H.R.); (J.V.); (M.E.); (G.S.); (D.R.)
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15
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Hillebrand F, Ostermann PN, Müller L, Degrandi D, Erkelenz S, Widera M, Pfeffer K, Schaal H. Gymnotic Delivery of LNA Mixmers Targeting Viral SREs Induces HIV-1 mRNA Degradation. Int J Mol Sci 2019; 20:ijms20051088. [PMID: 30832397 PMCID: PMC6429378 DOI: 10.3390/ijms20051088] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 02/22/2019] [Accepted: 02/25/2019] [Indexed: 02/07/2023] Open
Abstract
Transcription of the HIV-1 provirus generates a viral pre-mRNA, which is alternatively spliced into more than 50 HIV-1 mRNAs encoding all viral proteins. Regulation of viral alternative splice site usage includes the presence of splicing regulatory elements (SREs) which can dramatically impact RNA expression and HIV-1 replication when mutated. Recently, we were able to show that two viral SREs, GI3-2 and ESEtat, are important players in the generation of viral vif, vpr and tat mRNAs. Furthermore, we demonstrated that masking these SREs by transfected locked nucleic acid (LNA) mixmers affect the viral splicing pattern and viral particle production. With regard to the development of future therapeutic LNA mixmer-based antiretroviral approaches, we delivered the GI3-2 and the ESEtat LNA mixmers “nakedly”, without the use of transfection reagents (gymnosis) into HIV-1 infected cells. Surprisingly, we observed that gymnotically-delivered LNA mixmers accumulated in the cytoplasm, and seemed to co-localize with GW bodies and induced degradation of mRNAs containing their LNA target sequence. The GI3-2 and the ESEtat LNA-mediated RNA degradation resulted in abrogation of viral replication in HIV-1 infected Jurkat and PM1 cells as well as in PBMCs.
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Affiliation(s)
- Frank Hillebrand
- Institute of Virology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Philipp Niklas Ostermann
- Institute of Virology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Lisa Müller
- Institute of Virology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Daniel Degrandi
- Institute of Medical Microbiology and Hospital Hygiene, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Steffen Erkelenz
- Institute of Virology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Marek Widera
- Institute of Virology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Klaus Pfeffer
- Institute of Medical Microbiology and Hospital Hygiene, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
| | - Heiner Schaal
- Institute of Virology, Medical Faculty, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany.
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16
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Sertznig H, Hillebrand F, Erkelenz S, Schaal H, Widera M. Behind the scenes of HIV-1 replication: Alternative splicing as the dependency factor on the quiet. Virology 2018; 516:176-188. [PMID: 29407375 DOI: 10.1016/j.virol.2018.01.011] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/10/2018] [Accepted: 01/11/2018] [Indexed: 01/31/2023]
Abstract
Alternative splicing plays a key role in the HIV-1 life cycle and is essential to maintain an equilibrium of mRNAs that encode viral proteins and polyprotein-isoforms. In particular, since all early HIV-1 proteins are expressed from spliced intronless and late enzymatic and structural proteins from intron containing, i.e. splicing repressed viral mRNAs, cellular splicing factors and splicing regulatory proteins are crucial for the replication capacity. In this review, we will describe the complex network of cis-acting splicing regulatory elements (SREs), which are mainly localized in the neighbourhoods of all HIV-1 splice sites and warrant the proper ratio of individual transcript isoforms. Since SREs represent binding sites for trans-acting cellular splicing factors interacting with the cellular spliceosomal apparatus we will review the current knowledge of interactions between viral RNA and cellular proteins as well as their impact on viral replication. Finally, we will discuss potential therapeutic approaches targeting HIV-1 alternative splicing.
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Affiliation(s)
- Helene Sertznig
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Frank Hillebrand
- Institute of Virology, Heinrich Heine University, University Hospital, Düsseldorf, Germany
| | - Steffen Erkelenz
- Institute for Genetics, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Germany
| | - Heiner Schaal
- Institute of Virology, Heinrich Heine University, University Hospital, Düsseldorf, Germany
| | - Marek Widera
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
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17
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Buck HM. Modified RNA with a Phosphate-Methylated Backbone. A Serious Omission in Our (Retracted) Study at HIV-1 RNA Loops and Integrated DNA. Specific Properties of the (Modified) RNA and DNA Dimers. ACTA ACUST UNITED AC 2016. [DOI: 10.4236/jbpc.2016.71003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Fakhfakh K, Marais O, Cheng XBJ, Castañeda JR, Hughesman CB, Haynes C. Molecular thermodynamics of LNA:LNA base pairs and the hyperstabilizing effect of 5′-proximal LNA:DNA base pairs. AIChE J 2015. [DOI: 10.1002/aic.14916] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Kareem Fakhfakh
- Michael Smith Laboratories, University of British Columbia; Vancouver BC Canada
- Dept. of Chemical and Biological Engineering; University of British Columbia; Vancouver BC Canada
| | - Olivia Marais
- Dept. of Chemical and Biological Engineering; University of British Columbia; Vancouver BC Canada
| | - Xin Bo Justin Cheng
- Dept. of Chemical and Biological Engineering; University of British Columbia; Vancouver BC Canada
| | - Jorge Real Castañeda
- Dept. of Chemical and Biological Engineering; University of British Columbia; Vancouver BC Canada
| | - Curtis B. Hughesman
- Michael Smith Laboratories, University of British Columbia; Vancouver BC Canada
| | - Charles Haynes
- Michael Smith Laboratories, University of British Columbia; Vancouver BC Canada
- Dept. of Chemical and Biological Engineering; University of British Columbia; Vancouver BC Canada
- RES'EAU Water Research Network, Dept. of Chemical and Biological Engineering; University of British Columbia; Vancouver BC Canada
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19
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Kogami M, Koketsu M. An efficient method for the synthesis of selenium modified nucleosides: its application in the synthesis of Se-adenosyl-l-selenomethionine (SeAM). Org Biomol Chem 2015; 13:9405-17. [DOI: 10.1039/c5ob01316j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A versatile method for the synthesis of 5′-selenium modified nucleosides has been explored on the basis of a 2-(trimethylsilyl)ethyl (TSE) selenyl group.
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Affiliation(s)
- Masakazu Kogami
- Department of Chemistry and Biomolecular Science
- Faculty of Engineering
- Gifu University
- Gifu 501-1193
- Japan
| | - Mamoru Koketsu
- Department of Chemistry and Biomolecular Science
- Faculty of Engineering
- Gifu University
- Gifu 501-1193
- Japan
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20
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Therapeutic potential of siRNA and DNAzymes in cancer. Tumour Biol 2014; 35:9505-21. [PMID: 25149153 DOI: 10.1007/s13277-014-2477-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/07/2014] [Indexed: 02/07/2023] Open
Abstract
Cancer is characterized by uncontrolled cell growth, invasion, and metastasis and possess threat to humans worldwide. The scientific community is facing numerous challenges despite several efforts to cure cancer. Though a number of studies were done earlier, the molecular mechanism of cancer progression is not completely understood. Currently available treatments like surgery resection, adjuvant chemotherapy, and radiotherapy are not completely effective in curing all the cancers. Recent advances in the antisense technology provide a powerful tool to investigate various cancer pathways and target them. Small interfering RNAs (siRNAs) could be effective in downregulating the cancer-associated genes, but their in vivo delivery is the main obstacle. DNA enzymes (DNAzymes) have great potential in the treatment of cancer due to high selectivity and significant catalytic efficiency. In this review, we are focusing on antisense molecules such as siRNA and DNAzymes in cancer therapeutics development. This review also describes the challenges and approaches to overcome obstacles involved in using siRNA and DNAzymes in the treatment of cancers.
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21
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Suresh G, Priyakumar UD. Atomistic investigation of the effect of incremental modification of deoxyribose sugars by locked nucleic acid (β-D-LNA and α-L-LNA) moieties on the structures and thermodynamics of DNA-RNA hybrid duplexes. J Phys Chem B 2014; 118:5853-63. [PMID: 24845216 DOI: 10.1021/jp5014779] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chemically modified oligonucleotides offer many possibilities in utilizing their special features for a vast number of applications in nucleic acid based therapies and synthetic molecular biology. Locked nucleic acid analogues (α-/β-LNA) are modifications having an extra ring of 2'-O,4'-C-methylene group in the furanose sugar. LNA strands have been shown to exhibit high binding affinity toward RNA and DNA strands, and the resultant duplexes show significantly high melting temperatures. In the present study, molecular dynamics (MD) simulations were performed on DNA-RNA hybrid duplexes by systematically modifying their deoxyribose sugars with locked nucleic acid analogues. Several geometrical and energetic analyses were performed using principal component (PCA) analysis and binding free energy methods to understand the consequence of incorporated isomeric LNA modifications on the structure, dynamics, and stability of DNA-RNA hybrid duplex. The β-modification systematically changes the conformation of the DNA-RNA hybrid duplex whereas drastic changes are observed for α-modification. The fully modified duplexes have distinct properties compared to partial and unmodified duplexes, and the partly modified duplexes have properties intermediate to full strand and unmodified duplexes. The distribution of BI versus BII populations suggests that backbone rearrangement is minimal for β-LNA modification in order to accommodate it in duplexes whereas extensive backbone rearrangement is necessary in order to incorporate α-LNA modification which subsequently alters the energetic and structural properties of the duplexes. The simulation results also suggest that the alteration of DNA-RNA hybrid properties depends on the position of modification and the gap between the modifications.
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Affiliation(s)
- Gorle Suresh
- Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology , Hyderabad 500 032, India
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22
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Improvement of a streptavidin-binding aptamer by LNA- and α-l-LNA-substitutions. Bioorg Med Chem Lett 2014; 24:2273-7. [PMID: 24745966 DOI: 10.1016/j.bmcl.2014.03.082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 03/24/2014] [Accepted: 03/25/2014] [Indexed: 12/20/2022]
Abstract
Forty modified versions of a streptavidin-binding aptamer each containing single or multiple LNA or α-l-LNA-substitutions were synthesized and their dissociation constants determined by surface plasmon resonance experiments. Both full-length and truncated versions of the aptamer were studied and compared with the unmodified DNA aptamers. A ∼two-fold improvement in binding affinity was achieved by incorporation of LNA nucleotides in the 3'-part of the stems of the streptavidin-binding aptamer whereas LNA- and α-l-LNA-substitutions in the terminal stem increased the serum stability.
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23
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Russo Krauss I, Parkinson GN, Merlino A, Mattia CA, Randazzo A, Novellino E, Mazzarella L, Sica F. A regular thymine tetrad and a peculiar supramolecular assembly in the first crystal structure of an all-LNA G-quadruplex. ACTA ACUST UNITED AC 2014; 70:362-70. [PMID: 24531470 DOI: 10.1107/s1399004713028095] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 10/13/2013] [Indexed: 01/19/2023]
Abstract
Locked nucleic acids (LNAs) are formed by bicyclic ribonucleotides where the O2' and C4' atoms are linked through a methylene bridge and the sugar is blocked in a 3'-endo conformation. They represent a promising tool for therapeutic and diagnostic applications and are characterized by higher thermal stability and nuclease resistance with respect to their natural counterparts. However, structural descriptions of LNA-containing quadruplexes are rather limited, since few NMR models have been reported in the literature. Here, the first crystallographically derived model of an all-LNA-substituted quadruplex-forming sequence 5'-TGGGT-3' is presented refined at 1.7 Å resolution. This high-resolution crystallographic analysis reveals a regular parallel G-quadruplex arrangement terminating in a well defined thymine tetrad at the 3'-end. The detailed picture of the hydration pattern reveals LNA-specific features in the solvent distribution. Interestingly, two closely packed quadruplexes are present in the asymmetric unit. They face one another with their 3'-ends giving rise to a compact higher-order structure. This new assembly suggests a possible way in which sequential quadruplexes can be disposed in the crowded cell environment. Furthermore, as the formation of ordered structures by molecular self-assembly is an effective strategy to obtain nanostructures, this study could open the way to the design of a new class of LNA-based building blocks for nanotechnology.
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Affiliation(s)
- Irene Russo Krauss
- Department of Chemical Sciences, University of Naples `Federico II', Complesso Universitario di Monte Sant'Angelo, Via Cinthia, I-80126 Napoli, Italy
| | - Gary Nigel Parkinson
- Department of Pharmaceutical and Biological Chemistry, UCL School of Pharmacy, University College London, 29-39 Brunswick Square, London WC1N 1AX, England
| | - Antonello Merlino
- Department of Chemical Sciences, University of Naples `Federico II', Complesso Universitario di Monte Sant'Angelo, Via Cinthia, I-80126 Napoli, Italy
| | - Carlo Andrea Mattia
- Department of Pharmacy, University of Salerno, Via Ponte Don Melillo, I-84084 Fisciano, Italy
| | - Antonio Randazzo
- Department of Pharmacy, University of Naples `Federico II', Via D. Montesano 49, I-80131 Napoli, Italy
| | - Ettore Novellino
- Department of Pharmacy, University of Naples `Federico II', Via D. Montesano 49, I-80131 Napoli, Italy
| | - Lelio Mazzarella
- Department of Chemical Sciences, University of Naples `Federico II', Complesso Universitario di Monte Sant'Angelo, Via Cinthia, I-80126 Napoli, Italy
| | - Filomena Sica
- Department of Chemical Sciences, University of Naples `Federico II', Complesso Universitario di Monte Sant'Angelo, Via Cinthia, I-80126 Napoli, Italy
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24
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Zhang J, Lu D, Li A, Yang J, Wang S. Design, synthesis and anti-influenza virus activities of terminal modified antisense oligonucleotides. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2013.10.129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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25
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A library of programmable DNAzymes that operate in a cellular environment. Sci Rep 2013; 3:1535. [PMID: 23525068 PMCID: PMC3607177 DOI: 10.1038/srep01535] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 02/26/2013] [Indexed: 01/16/2023] Open
Abstract
DNAzymes were used as inhibitory agents in a variety of experimental disease settings, such as cancer, viral infections and even HIV. Drugs that become active only upon the presence of preprogrammed abnormal environmental conditions may enable selective molecular therapy by targeting abnormal cells without injuring normal cells. Here we show a novel programmable DNAzyme library composed of variety of Boolean logic gates, including YES, AND, NOT, OR, NAND, ANDNOT, XOR, NOR and 3-input-AND gate, that uses both miRNAs and mRNAs as inputs. Each gate is based on the c-jun cleaving Dz13 DNAzyme and active only in the presence of specific input combinations. The library is modular, supports arbitrary inputs and outputs, cascadable, highly specific and robust. We demonstrate the library's potential diagnostic abilities on miRNA and mRNA combinations in cell lysate and its ability to operate in a cellular environment by using beacon-like c-jun mimicking substrate in living mammalian cells.
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26
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Suresh G, Priyakumar UD. Structures, dynamics, and stabilities of fully modified locked nucleic acid (β-D-LNA and α-L-LNA) duplexes in comparison to pure DNA and RNA duplexes. J Phys Chem B 2013; 117:5556-64. [PMID: 23617391 DOI: 10.1021/jp4016068] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Locked nucleic acid (LNA) is a chemical modification which introduces a -O-CH2- linkage in the furanose sugar of nucleic acids and blocks its conformation in a particular state. Two types of modifications, namely, 2'-O,4'-C-methylene-β-D-ribofuranose (β-D-LNA) and 2'-O,4'-C-methylene-α-L-ribofuranose (α-L-LNA), have been shown to yield RNA and DNA duplex-like structures, respectively. LNA modifications lead to increased melting temperatures of DNA and RNA duplexes, and have been suggested as potential therapeutic agents in antisense therapy. In this study, molecular dynamics (MD) simulations were performed on fully modified LNA duplexes and pure DNA and RNA duplexes sharing a similar sequence to investigate their structure, stabilities, and solvation properties. Both LNA duplexes undergo unwinding of the helical structure compared to the pure DNA and RNA duplexes. Though the α-LNA substituent has been proposed to mimic deoxyribose sugar in its conformational properties, the fully modified duplex was found to exhibit unique structural and dynamic properties with respect to the other three nucleic acid structures. Free energy calculations accurately capture the enhanced stabilization of the LNA duplex structures compared to DNA and RNA molecules as observed in experiments. π-stacking interaction between bases from complementary strands is shown to be one of the contributors to enhanced stabilization upon LNA substitution. A combination of two factors, namely, nature of the -O-CH2- linkage in the LNAs vs their absence in the pure duplexes and similar conformations of the sugar rings in DNA and α-LNA vs the other two, is suggested to contribute to the stark differences among the four duplexes studied here in terms of their structural, dynamic, and energetic properties.
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Affiliation(s)
- Gorle Suresh
- Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Hyderabad, India
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27
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Gorjipour F, Sharifi Z, Samadikuchaksaraei A, Farajollahi MM, Hosseini A. Cloning, Soluble Expression and Immunoreactivity of HIV-1 CRF35_AD p24 Protein Infusion with HP-thioredoxin from Iranian Clinical Isolates. Lab Med 2012. [DOI: 10.1309/lmevsoib3lhmctyh] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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28
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Kim JE, Yoon S, Mok H, Jung W, Kim DE. Site-specific cleavage of mutant ABL mRNA by DNAzyme is facilitated by peptide nucleic acid binding to RNA substrate. FEBS Lett 2012; 586:3865-9. [PMID: 23010596 DOI: 10.1016/j.febslet.2012.09.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/04/2012] [Accepted: 09/08/2012] [Indexed: 01/01/2023]
Abstract
RNA-cleaving DNAzymes were constructed to target the point mutation in the BCR-ABL transcript that causes imatinib resistance in leukemic cells. We examined the effect of 12mer peptide nucleic acids (PNAs) as facilitator oligonucleotides that bind to RNA substrate at the termini of the DNAzyme to improve DNAzyme-mediated cleavage of full-length RNA. When imatinib-resistant cells were transfected with the facilitator PNA and DNAzyme, DNAzyme activity was enhanced and the cells were sensitized to imatinib treatment. Thus, facilitator PNA may be used to enhance activity of antisense oligonucleotide targeting the full-length transcript.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Base Sequence
- Benzamides
- Cell Line, Tumor
- DNA, Catalytic/chemical synthesis
- DNA, Catalytic/genetics
- DNA, Catalytic/metabolism
- Genes, abl
- Genetic Engineering
- Humans
- Imatinib Mesylate
- Mice
- Molecular Sequence Data
- Nucleic Acid Conformation
- Oligonucleotides, Antisense/genetics
- Peptide Nucleic Acids/chemistry
- Peptide Nucleic Acids/genetics
- Peptide Nucleic Acids/metabolism
- Piperazines/pharmacology
- Polymorphism, Single Nucleotide
- Pyrimidines/pharmacology
- RNA Cleavage/drug effects
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Substrate Specificity
- Transfection
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Affiliation(s)
- Ji Eun Kim
- Department of Bioscience and Biotechnology, Konkuk University, Seoul, Republic of Korea
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29
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RNA-Cleaving DNA Enzymes and Their Potential Therapeutic Applications as Antibacterial and Antiviral Agents. FROM NUCLEIC ACIDS SEQUENCES TO MOLECULAR MEDICINE 2012. [PMCID: PMC7119987 DOI: 10.1007/978-3-642-27426-8_15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
DNA catalysts are synthetic single-stranded DNA molecules that have been identified by in vitro selection from random sequence DNA pools. The most prominent representatives of DNA catalysts (also known as DNA enzymes, deoxyribozymes, or DNAzymes) catalyze the site-specific cleavage of RNA substrates. Two distinct groups of RNA-cleaving DNA enzymes are the 10-23 and 8-17 enzymes. A typical RNA-cleaving DNA enzyme consists of a catalytic core and two short binding arms which form Watson–Crick base pairs with the RNA targets. RNA cleavage is usually achieved with the assistance of metal ions such as Mg2+, Ca2+, Mn2+, Pb2+, or Zn2+, but several chemically modified DNA enzymes can cleave RNA in the absence of divalent metal ions. A number of studies have shown the use of 10-23 DNA enzymes for modest downregulation of therapeutically relevant RNA targets in cultured cells and in whole mammals. Here we focus on mechanistic aspects of RNA-cleaving DNA enzymes and their potential to silence therapeutically appealing viral and bacterial gene targets. We also discuss delivery options and challenges involved in DNA enzyme-based therapeutic strategies.
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30
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Features of "All LNA" Duplexes Showing a New Type of Nucleic Acid Geometry. J Nucleic Acids 2012; 2012:156035. [PMID: 22666550 PMCID: PMC3361345 DOI: 10.1155/2012/156035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 03/01/2012] [Indexed: 12/18/2022] Open
Abstract
"Locked nucleic acids" (LNAs) belong to the backbone-modified nucleic acid family. The 2'-O,4'-C-methylene-β-D-ribofuranose nucleotides are used for single or multiple substitutions in RNA molecules and thereby introduce enhanced bio- and thermostability. This renders LNAs powerful tools for diagnostic and therapeutic applications. RNA molecules maintain the overall canonical A-type conformation upon substitution of single or multiple residues/nucleotides by LNA monomers. The structures of "all" LNA homoduplexes, however, exhibit significant differences in their overall geometry, in particular a decreased twist, roll and propeller twist. This results in a widening of the major groove, a decrease in helical winding, and an enlarged helical pitch. Therefore, the LNA duplex structure can no longer be described as a canonical A-type RNA geometry but can rather be brought into proximity to other backbone-modified nucleic acids, like glycol nucleic acids or peptide nucleic acids. LNA-modified nucleic acids provide thus structural and functional features that may be successfully exploited for future application in biotechnology and drug discovery.
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Liu CH, Lu DD, Deng XX, Wang Y, Zhang JY, Zhang YL, Wang SQ. The analysis of major impurities of lipophilic-conjugated phosphorothioate oligonucleotides by ion-pair reversed-phase HPLC combined with MALDI-TOF-MS. Anal Bioanal Chem 2012; 403:1333-42. [PMID: 22441199 DOI: 10.1007/s00216-012-5935-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 03/07/2012] [Accepted: 03/07/2012] [Indexed: 12/13/2022]
Abstract
A simple and rapid ion-pair reversed phase high-performance liquid chromatography (IP-RP-HPLC) method was developed to analyse the major impurities of lipophilic-conjugated phosphorothioate oligonucleotides (ODNs), which provided better separation performance than capillary gel electrophoresis and ion exchange chromatograph methods. The study showed that covalent conjugations of lipophilic group (docosanyl, C(22)) to ODN at 5'-termini (denoted as 5'C(22)-Flu) or 3'-termini (denoted as 3'C(22)-Flu) exhibited similar chromatographic retention behavior. Some important analytical conditions of IP-RP-HPLC, including column type, ion-pairing buffer composition, and separation temperature, were investigated for the effects on the separation of crude 5'C(22)-Flu. As expected, the method developed was successfully applied to the analysis of crude 3'C(22)-Flu and both purified products. Furthermore, the related impurities derived from the synthetic process were identified by matrix-assisted laser desorption-ionization time-of-flight mass spectrum. These MS results are of benefit to understanding the major process-related impurities in lipophilic-ODN conjugates synthesis, thereby elevating the quality of target products.
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Affiliation(s)
- Cai-Hong Liu
- Chinese PLA Postgraduate Medical School, Beijing, China
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32
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Coppock MB, Williams ME. Nucleic Acid Mimetics. Supramol Chem 2012. [DOI: 10.1002/9780470661345.smc169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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33
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Fokina AA, Meschaninova MI, Durfort T, Venyaminova AG, François JC. Targeting insulin-like growth factor I with 10-23 DNAzymes: 2'-O-methyl modifications in the catalytic core enhance mRNA cleavage. Biochemistry 2012; 51:2181-91. [PMID: 22352843 DOI: 10.1021/bi201532q] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Insulin-like growth factor I (IGF-I) and its cognate receptor (IGF-1R) contribute to normal cell function and to tumorigenesis. The role of IGF-I signaling in tumor growth has been demonstrated in vivo using nucleic acid-based strategies. Here, we designed the first 10-23 DNAzymes directed against IGF-I mRNA. Unlike antisense approaches and RNA interference that require protein catalysis, DNAzymes catalyze protein-free RNA cleavage. We identified target sequences and measured catalytic properties of differently designed DNAzymes on short synthetic RNA targets and on in vitro transcribed IGF-I mRNA. The most efficient cleavers were then transfected into cells, and their inhibitory effect was analyzed using reporter gene assays. We found that increasing the size of DNAzyme flanking sequences and modifications of the termini with 2'-O-methyl residues improved cleavage rates of target RNAs. Modification of the catalytic loop with six 2'-O-methyl ribonucleotides at nonessential positions increased or decreased catalytic efficiency depending on the mRNA target site. In cells, DNAzymes with 2'-O-methyl-modified catalytic cores and flanking sequences were able to inhibit reporter gene activity because of specific recognition and cleavage of IGF-I mRNA sequences. Mutant DNAzymes with inactive catalytic cores were unable to block reporter gene expression, demonstrating that the RNA cleaving ability of 10-23 DNAzymes contributed to inhibitory mechanisms. Our results show that nuclease-resistant 2'-O-methyl-modified DNAzymes with high catalytic efficiencies are useful for inhibiting IGF-I gene function in cells.
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Affiliation(s)
- Alesya A Fokina
- INSERM, U565, Acides nucléiques: dynamique, ciblage et fonctions biologiques, 75005 Paris, France
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Grimpe B. Deoxyribozymes and bioinformatics: complementary tools to investigate axon regeneration. Cell Tissue Res 2011; 349:181-200. [PMID: 22190188 PMCID: PMC7087747 DOI: 10.1007/s00441-011-1291-6] [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: 09/08/2011] [Accepted: 11/17/2011] [Indexed: 11/28/2022]
Abstract
For over 100 years, scientists have tried to understand the mechanisms that lead to the axonal growth seen during development or the lack thereof during regeneration failure after spinal cord injury (SCI). Deoxyribozyme technology as a potential therapeutic to treat SCIs or other insults to the brain, combined with a bioinformatics approach to comprehend the complex protein-protein interactions that occur after such trauma, is the focus of this review. The reader will be provided with information on the selection process of deoxyribozymes and their catalytic sequences, on the mechanism of target digestion, on modifications, on cellular uptake and on therapeutic applications and deoxyribozymes are compared with ribozymes, siRNAs and antisense technology. This gives the reader the necessary knowledge to decide which technology is adequate for the problem at hand and to design a relevant agent. Bioinformatics helps to identify not only key players in the complex processes that occur after SCI but also novel or less-well investigated molecules against which new knockdown agents can be generated. These two tools used synergistically should facilitate the pursuit of a treatment for insults to the central nervous system.
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Affiliation(s)
- Barbara Grimpe
- Applied Neurobiology, Department of Neurology, Heinrich Heine University Düsseldorf, Moorenstrasse 5, 40225 Düsseldorf, Germany.
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35
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Doessing H, Vester B. Locked and unlocked nucleosides in functional nucleic acids. Molecules 2011; 16:4511-26. [PMID: 21629180 PMCID: PMC6264650 DOI: 10.3390/molecules16064511] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 05/19/2011] [Accepted: 05/25/2011] [Indexed: 12/28/2022] Open
Abstract
Nucleic acids are able to adopt a plethora of structures, many of which are of interest in therapeutics, bio- or nanotechnology. However, structural and biochemical stability is a major concern which has been addressed by incorporating a range of modifications and nucleoside derivatives. This review summarizes the use of locked nucleic acid (LNA) and un-locked nucleic acid (UNA) monomers in functional nucleic acids such as aptamers, ribozymes, and DNAzymes.
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Affiliation(s)
| | - Birte Vester
- Nucleic Acid Center, Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M 5230, Denmark; E-Mail: (H.D.)
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36
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Kaur H, Scaria V, Maiti S. “Locked onto the target”: increasing the efficiency of antagomirzymes using locked nucleic acid modifications. Biochemistry 2011; 49:9449-56. [PMID: 20879750 DOI: 10.1021/bi101185k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This study highlights the effect of incorporation of locked nucleic acid (LNA) on improving the functional efficacy of DNAzymes against microRNAs (antagomirzymes). DNAzymes were designed against two different sites of miR-27a, which were encompassed both within the precursor and mature form of miRNA. The cleavage and functional activities of these DNAzymes have been compared to those of LNA-modified counterparts, containing LNA modification in each of the substrate binding arms. Preliminary examination based on in vitro cleavage demonstrated LNAzyme to be much more effective in the ensuing cleavage of target miRNA under both single- and multiple-turnover conditions. Evaluation of kinetic parameters indicated almost 5-fold higher cleavage efficiency, kobs, for LNAzymes than for DNAzymes, leading to more efficient cleavage of the substrate. We attribute this enhancement in cleavage efficiency to the LNA-mediated improvement in the hybridization of the antagomirzyme·target complex. Functional validation of the relative activities was accomplished through the luciferase reporter assay and quantitative real-time polymerase chain reaction (qRT-PCR). Both the unmodified and LNA-modified antagomirzymes were very active in ensuing efficient miRNA knockdown; however, compared to the DNAzymes, the LNAzymes were almost 25% more active. A direct quantitative estimate of miRNA cleavage, conducted using qRT-PCR, further substantiated the data by indicating that LNAzyme effectively downregulated the levels of mature miRNA (up to 50%) versus the corresponding DNAzymes. Our data thus provide formative evidence of the successful employment of LNA-based antagomirzymes against miRNA.
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Affiliation(s)
- Harleen Kaur
- Institute of Genomics and Integrative Biology, CSIR, Delhi, India
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37
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Campbell MA, Wengel J. Locked vs. unlocked nucleic acids (LNA vs. UNA): contrasting structures work towards common therapeutic goals. Chem Soc Rev 2011; 40:5680-9. [PMID: 21556437 DOI: 10.1039/c1cs15048k] [Citation(s) in RCA: 176] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Oligonucleotide chemistry has been developed greatly over the past three decades, with many advances in increasing nuclease resistance, enhancing duplex stability and assisting with cellular uptake. Locked nucleic acid (LNA) is a structurally rigid modification that increases the binding affinity of a modified-oligonucleotide. In contrast, unlocked nucleic acid (UNA) is a highly flexible modification, which can be used to modulate duplex characteristics. In this tutorial review, we will compare the synthetic routes to both of these modifications, contrast the structural features, examine the hybridization properties of LNA and UNA modified duplexes, and discuss how they have been applied within biotechnology and drug research. LNA has found widespread use in antisense oligonucleotide technology, where it can stabilize interactions with target RNA and protect from cellular nucleases. The newly emerging field of siRNAs has made use of LNA and, recently, also UNA. These modifications are able to increase double-stranded RNA stability in serum and decrease off-target effects seen with conventional siRNAs. LNA and UNA are also emerging as versatile modifications for aptamers. Their application to known aptamer structures has opened up the possibility of future selection of LNA-modified aptamers. Each of these oligonucleotide technologies has the potential to become a new type of therapy to treat a wide variety of diseases, and LNA and UNA will no doubt play a part in future developments of therapeutic and diagnostic oligonucleotides.
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Affiliation(s)
- Meghan A Campbell
- Nucleic Acid Center, Institute for Physics and Chemistry, University of Southern Denmark, Odense, Denmark
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38
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Dutta S, Bhaduri N, Rastogi N, Chandel SG, Vandavasi JK, Upadhayaya RS, Chattopadhyaya J. Carba-LNA modified siRNAs targeting HIV-1 TAR region downregulate HIV-1 replication successfully with enhanced potency. MEDCHEMCOMM 2011. [DOI: 10.1039/c0md00225a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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39
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Sugiyama R, Hayafune M, Habu Y, Yamamoto N, Takaku H. HIV-1 RT-dependent DNAzyme expression inhibits HIV-1 replication without the emergence of escape viruses. Nucleic Acids Res 2011; 39:589-98. [PMID: 20833635 PMCID: PMC3025543 DOI: 10.1093/nar/gkq794] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 08/18/2010] [Accepted: 08/23/2010] [Indexed: 12/12/2022] Open
Abstract
DNAzymes are easier to prepare and less sensitive to chemical and enzymatic degradation than ribozymes; however, a DNA enzyme expression system has not yet been developed. In this study, we exploited the mechanism of HIV-1 reverse transcription (RT) in a DNA enzyme expression system. We constructed HIV-1 RT-dependent lentiviral DNAzyme expression vectors including the HIV-1 primer binding site, the DNA enzyme, and either a native tRNA (Lys-3), tR(M)DtR(L), or one of two truncated tRNAs (Lys-3), tR(M)DΔARMtR(L) or tR(M)D3'-endtR(L). Lentiviral vector-mediated DNAzyme expression showed high levels of inhibition of HIV-1 replication in SupT1 cells. We also demonstrated the usefulness of this approach in a long-term assay, in which we found that the DNAzymes prevented escape from inhibition of HIV. These results suggest that HIV-1 RT-dependent lentiviral vector-derived DNAzymes prevent the emergence of escape mutations.
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Affiliation(s)
- Ryuichi Sugiyama
- Department of Life and Environmental Science, High Technology Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi, Chiba 275-0016, Japan, Department of Microbiology, Immunology and Pathology 1619 Campus Delivery, Colorado State University, Fort Collins, CO 80523-161, USA and Influenza Virus Research Center, National Institute of Infectious Diseases, 4-7-1 Musashimurayama-shi, Tokyo 208-0011, Japan
| | - Masaaki Hayafune
- Department of Life and Environmental Science, High Technology Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi, Chiba 275-0016, Japan, Department of Microbiology, Immunology and Pathology 1619 Campus Delivery, Colorado State University, Fort Collins, CO 80523-161, USA and Influenza Virus Research Center, National Institute of Infectious Diseases, 4-7-1 Musashimurayama-shi, Tokyo 208-0011, Japan
| | - Yuichiro Habu
- Department of Life and Environmental Science, High Technology Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi, Chiba 275-0016, Japan, Department of Microbiology, Immunology and Pathology 1619 Campus Delivery, Colorado State University, Fort Collins, CO 80523-161, USA and Influenza Virus Research Center, National Institute of Infectious Diseases, 4-7-1 Musashimurayama-shi, Tokyo 208-0011, Japan
| | - Norio Yamamoto
- Department of Life and Environmental Science, High Technology Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi, Chiba 275-0016, Japan, Department of Microbiology, Immunology and Pathology 1619 Campus Delivery, Colorado State University, Fort Collins, CO 80523-161, USA and Influenza Virus Research Center, National Institute of Infectious Diseases, 4-7-1 Musashimurayama-shi, Tokyo 208-0011, Japan
| | - Hiroshi Takaku
- Department of Life and Environmental Science, High Technology Research Center, Chiba Institute of Technology, 2-17-1 Tsudanuma, Narashino-shi, Chiba 275-0016, Japan, Department of Microbiology, Immunology and Pathology 1619 Campus Delivery, Colorado State University, Fort Collins, CO 80523-161, USA and Influenza Virus Research Center, National Institute of Infectious Diseases, 4-7-1 Musashimurayama-shi, Tokyo 208-0011, Japan
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40
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Jahn K, Olsen EM, Nielsen MM, Tørring T, MohammadZadegan R, Andersen ES, Gothelf KV, Kjems J. Site-Specific Chemical Labeling of Long RNA Molecules. Bioconjug Chem 2010; 22:95-100. [DOI: 10.1021/bc100422k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kasper Jahn
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Eva Maria Olsen
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Morten Muhlig Nielsen
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Thomas Tørring
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Reza MohammadZadegan
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Ebbe Sloth Andersen
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Kurt Vesterager Gothelf
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
| | - Jørgen Kjems
- Danish National Research Foundation, Center for DNA Nanotechnology (CDNA) at Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology, and Department of Chemistry, Aarhus University, DK-8000 Aarhus, Denmark
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41
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Veedu RN, Wengel J. Locked nucleic acids: promising nucleic acid analogs for therapeutic applications. Chem Biodivers 2010; 7:536-42. [PMID: 20232325 DOI: 10.1002/cbdv.200900343] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Locked Nucleic Acid (LNA) is a unique nucleic-acid modification possessing very high binding affinity and excellent specificity toward complementary RNA or DNA oligonucleotides. The remarkable properties exhibited by LNA oligonucleotides have been employed in different nucleic acid-based therapeutic strategies both in vitro and in vivo. Herein, we highlight the applications of LNA nucleotides for controlling gene expression.
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Affiliation(s)
- Rakesh N Veedu
- Nucleic Acid Center, Department of Physics and Chemistry, University of Southern Denmark, Campusvej 55, DK-5230 Odense M.
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42
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Eichert A, Behling K, Betzel C, Erdmann VA, Fürste JP, Förster C. The crystal structure of an 'All Locked' nucleic acid duplex. Nucleic Acids Res 2010; 38:6729-36. [PMID: 20530536 PMCID: PMC2965234 DOI: 10.1093/nar/gkq505] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
'Locked nucleic acids' (LNAs) are known to introduce enhanced bio- and thermostability into natural nucleic acids rendering them powerful tools for diagnostic and therapeutic applications. We present the 1.9 Å X-ray structure of an 'all LNA' duplex containing exclusively modified β-D-2'-O-4'C-methylene ribofuranose nucleotides. The helix illustrates a new type of nucleic acid geometry that contributes to the understanding of the enhanced thermostability of LNA duplexes. A notable decrease of several local and overall helical parameters like twist, roll and propeller twist influence the structure of the LNA helix and result in a widening of the major groove, a decrease in helical winding and an enlarged helical pitch. A detailed structural comparison to the previously solved RNA crystal structure with the corresponding base pair sequence underlines the differences in conformation. The surrounding water network of the RNA and the LNA helix shows a similar hydration pattern.
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Affiliation(s)
- André Eichert
- Institute of Chemistry and Biochemistry, Free University Berlin, 14195 Berlin, Germany
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43
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Bhattacharya S, Osman H. Novel targets for anti-retroviral therapy. J Infect 2009; 59:377-86. [DOI: 10.1016/j.jinf.2009.09.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2009] [Revised: 09/29/2009] [Accepted: 09/30/2009] [Indexed: 10/20/2022]
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44
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Förster C, Oberthuer D, Gao J, Eichert A, Quast FG, Betzel C, Nitsche A, Erdmann VA, Fürste JP. Crystallization and preliminary X-ray diffraction data of an LNA 7-mer duplex derived from a ricin aptamer. Acta Crystallogr Sect F Struct Biol Cryst Commun 2009; 65:881-5. [PMID: 19724123 PMCID: PMC2795591 DOI: 10.1107/s1744309109029145] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Accepted: 07/22/2009] [Indexed: 12/28/2022]
Abstract
Locked nucleic acids (LNAs) are modified nucleic acids which contain a modified sugar such as beta-D-2'-O,4'-C methylene-bridged ribofuranose or other sugar derivatives in LNA analogues. The beta-D-2'-O,4'-C methylene ribofuranose LNAs in particular possess high stability and melting temperatures, which makes them of interest for stabilizing the structure of different nucleic acids. Aptamers, which are DNAs or RNAs targeted against specific ligands, are candidates for substitution with LNAs in order to increase their stability. A 7-mer helix derived from the terminal part of an aptamer that was targeted against ricin was chosen. The ricin aptamer originally consisted of natural RNA building blocks and showed high affinity in ricin binding. For future stabilization of the aptamer, the terminal helix has been constructed as an ;all-locked' LNA and was successfully crystallized in order to investigate its structural properties. Optimization of crystal growth succeeded by the use of different metal salts as additives, such as CuCl(2), MgCl(2), MnCl(2), CaCl(2), CoCl(2) and ZnSO(4). Preliminary X-ray diffraction data were collected and processed to 2.8 A resolution. The LNA crystallized in space group P6(5), with unit-cell parameters a = 50.11, b = 50.11, c = 40.72 A. The crystals contained one LNA helix per asymmetric unit with a Matthews coefficient of 3.17 A(3) Da(-1), which implies a solvent content of 70.15%.
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Affiliation(s)
- Charlotte Förster
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Dominik Oberthuer
- Institute of Biochemistry and Food Chemistry, University of Hamburg, Notkestrasse 85, Building 22a, c/o DESY, 22603 Hamburg, Germany
| | - Jiang Gao
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - André Eichert
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Frederick G. Quast
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Christian Betzel
- Institute of Biochemistry and Food Chemistry, University of Hamburg, Notkestrasse 85, Building 22a, c/o DESY, 22603 Hamburg, Germany
| | - Andreas Nitsche
- Robert Koch-Institut, Zentrum für Biologische Sicherheit 1, Nordufer 20, 13353 Berlin, Germany
| | - Volker A. Erdmann
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
| | - Jens P. Fürste
- Institute of Chemistry and Biochemistry, Free University Berlin, Thielallee 63, 14195 Berlin, Germany
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45
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Moore MD, Hu WS. HIV-1 RNA dimerization: It takes two to tango. AIDS Rev 2009; 11:91-102. [PMID: 19529749 PMCID: PMC3056336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Each viral particle of HIV-1, the infectious agent of AIDS, contains two copies of the full-length viral genomic RNA. Encapsidating two copies of genomic RNA is one of the characteristics of the retrovirus family. The two RNA molecules are both positive-sense and often identical; furthermore, each RNA encodes the full complement of genetic information required for viral replication. The two strands of RNA are intricately entwined within the core of the mature infectious virus as a ribonuclear complex with the viral proteins, including nucleocapsid. Multiple steps in the biogenesis of the genomic full-length RNA are involved in achieving this location and dimeric state. The viral sequences and proteins involved in the process of RNA dimerization, both for the initial interstrand contact and subsequent steps that result in the condensed, stable conformation of the genomic RNA, are outlined in this review. In addition, the impact of the dimeric state of HIV-1 viral RNA is discussed with respect to its importance in efficient viral replication and, consequently, the potential development of antiviral strategies designed to disrupt the formation of dimeric RNA.
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Affiliation(s)
- Michael D Moore
- HIV Drug Resistance Program, National Cancer Institute, Frederick, MD 21702, USA
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46
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Abstract
For almost three decades, researchers have studied the possibility to use nucleic acids as antiviral therapeutics. In theory, compounds such as antisense oligonucleotides, ribozymes, DNAzymes, and aptamers can be designed to trigger the sequence-specific inhibition of particular mRNA transcripts, including viral genomes. However, difficulties with their efficiency, off-target effects, toxicity, delivery, and stability halted the development of nucleic acid-based therapeutics that can be used in the clinic. So far, only a single antisense drug, Vitravene for the treatment of CMV-induced retinitis in AIDS patients, has made it to the clinic. Since the discovery of RNA interference (RNAi), there is a renewed interest in the development of nucleic acid-based therapeutics. Antiviral RNAi approaches are highly effective in vitro and in animal models and are currently being tested in clinical trials. Here we give an overview of antiviral nucleic acid-based therapeutics. We focus on antisense and RNAi-based compounds that have been shown to be effective in animal model systems.
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Affiliation(s)
- Hans-Georg Kräusslich
- Hygiene Institute Department of Virology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, Heidelberg, 69120 Germany
| | - Ralf Bartenschlager
- Hygiene Institute Department of Virology, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, Heidelberg, 69120 Germany
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47
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Obika S, Kodama T, Sugaya K, Harada Y, Mitsuoka Y, Imanishi T. Synthesis and Properties of 2’-Deoxy-trans-3’,4’-BNA with S-Type Sugar Puckering. HETEROCYCLES 2009. [DOI: 10.3987/com-08-s(f)99] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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48
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L'Hernault A, Greatorex JS, Crowther RA, Lever AML. Dimerisation of HIV-2 genomic RNA is linked to efficient RNA packaging, normal particle maturation and viral infectivity. Retrovirology 2007; 4:90. [PMID: 18078509 PMCID: PMC2222663 DOI: 10.1186/1742-4690-4-90] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2007] [Accepted: 12/13/2007] [Indexed: 01/13/2023] Open
Abstract
Background Retroviruses selectively encapsidate two copies of their genomic RNA, the Gag protein binding a specific RNA motif in the 5' UTR of the genome. In human immunodeficiency virus type 2 (HIV-2), the principal packaging signal (Psi) is upstream of the major splice donor and hence is present on all the viral RNA species. Cotranslational capture of the full length genome ensures specificity. HIV-2 RNA dimerisation is thought to occur at the dimer initiation site (DIS) located in stem-loop 1 (SL-1), downstream of the main packaging determinant. However, the HIV-2 packaging signal also contains a palindromic sequence (pal) involved in dimerisation. In this study, we analysed the role of the HIV-2 packaging signal in genomic RNA dimerisation in vivo and its implication in viral replication. Results Using a series of deletion and substitution mutants in SL-1 and the Psi region, we show that in fully infectious HIV-2, genomic RNA dimerisation is mediated by the palindrome pal. Mutation of the DIS had no effect on dimerisation or viral infectivity, while mutations in the packaging signal severely reduce both processes as well as RNA encapsidation. Electron micrographs of the Psi-deleted virions revealed a significant reduction in the proportion of mature particles and an increase in that of particles containing multiple cores. Conclusion In addition to its role in RNA encapsidation, the HIV-2 packaging signal contains a palindromic sequence that is critical for genomic RNA dimerisation. Encapsidation of a dimeric genome seems required for the production of infectious mature particles, and provides a promising therapeutic target.
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Affiliation(s)
- Anne L'Hernault
- Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge CB2 2QQ, UK.
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Abstract
RNA interference (RNAi) is a conserved sequence-specific, gene-silencing mechanism that is induced by double-stranded RNA. RNAi holds great promise as a novel nucleic acid-based therapeutic against a wide variety of diseases, including cancer, infectious diseases and genetic disorders. Antiviral RNAi strategies have received much attention and several compounds are currently being tested in clinical trials. Although induced RNAi is able to trigger profound and specific inhibition of virus replication, it is becoming clear that RNAi therapeutics are not as straightforward as we had initially hoped. Difficulties concerning toxicity and delivery to the right cells that earlier hampered the development of antisense-based therapeutics may also apply to RNAi. In addition, there are indications that viruses have evolved ways to escape from RNAi. Proper consideration of all of these issues will be necessary in the design of RNAi-based therapeutics for successful clinical intervention of human pathogenic viruses.
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Affiliation(s)
- Joost Haasnoot
- Department of Medical Microbiology, Laboratory of Experimental Virology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center of the University of Amsterdam, Meibergdreef 15, Amsterdam, 1105 AZ The Netherlands
| | - Ellen M Westerhout
- Department of Medical Microbiology, Laboratory of Experimental Virology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center of the University of Amsterdam, Meibergdreef 15, Amsterdam, 1105 AZ The Netherlands
| | - Ben Berkhout
- Department of Medical Microbiology, Laboratory of Experimental Virology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center of the University of Amsterdam, Meibergdreef 15, Amsterdam, 1105 AZ The Netherlands
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50
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Donini S, Clerici M, Wengel J, Vester B, Peracchi A. The advantages of being locked. Assessing the cleavage of short and long RNAs by locked nucleic acid-containing 8-17 deoxyribozymes. J Biol Chem 2007; 282:35510-8. [PMID: 17908692 DOI: 10.1074/jbc.m706993200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
RNA-cleaving deoxyribozymes can be used for the sequence-specific knockdown of mRNAs. It was previously shown that activity of these deoxyribozymes is enhanced when their substrate-binding arms include some locked nucleic acid (LNA) residues, but the mechanistic basis of this enhancement was not explored. Here we dissected the kinetics and thermodynamics underlying the reaction of LNA-containing 8-17 deoxyribozymes. Four 8-17 constructs were designed to target sequences within the E6 mRNA from human papillomavirus type 16. When one of these deoxyribozymes (DNAzymes) and the corresponding LNA-armed enzyme (LNAzyme) were tested against a minimal RNA substrate, they showed similar rates of substrate binding and similar rates of intramolecular cleavage, but the LNAzyme released its substrate more slowly. The superior thermodynamic stability of the LNAzyme-substrate complex led to improved performances in reactions carried out at low catalyst concentrations. The four DNAzymes and the corresponding LNAzymes were then tested against extended E6 transcripts (>500 nucleotides long). With these structured substrates, the LNAzymes retained full activity, whereas the DNAzymes cleaved extremely poorly, unless they were allowed to pre-anneal to their targets. These results imply that LNAzymes can easily overcome the kinetic barrier represented by local RNA structure and bind to folded targets with a faster association rate as compared with DNAzymes. Such faster annealing to structured targets can be explained by a model whereby LNA monomers favor the initial hybridization to short stretches of unpaired residues ("nucleation"), which precedes disruption of the local mRNA structure and completion of the binding process.
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Affiliation(s)
- Stefano Donini
- Department of Biochemistry and Molecular Biology, University of Parma, 43100 Parma, Italy
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