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Ivanov GS, Tribulovich VG, Pestov NB, David TI, Amoah AS, Korneenko TV, Barlev NA. Artificial genetic polymers against human pathologies. Biol Direct 2022; 17:39. [PMID: 36474260 PMCID: PMC9727881 DOI: 10.1186/s13062-022-00353-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
Originally discovered by Nielsen in 1991, peptide nucleic acids and other artificial genetic polymers have gained a lot of interest from the scientific community. Due to their unique biophysical features these artificial hybrid polymers are now being employed in various areas of theranostics (therapy and diagnostics). The current review provides an overview of their structure, principles of rational design, and biophysical features as well as highlights the areas of their successful implementation in biology and biomedicine. Finally, the review discusses the areas of improvement that would allow their use as a new class of therapeutics in the future.
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Affiliation(s)
- Gleb S Ivanov
- Institute of Cytology, Tikhoretsky Ave 4, Saint Petersburg, Russia, 194064
- St. Petersburg State Technological Institute (Technical University), Saint Petersburg, Russia, 190013
| | - Vyacheslav G Tribulovich
- St. Petersburg State Technological Institute (Technical University), Saint Petersburg, Russia, 190013
| | - Nikolay B Pestov
- Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Moscow, Russia, 108819
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia, 141701
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia, 117997
- Institute of Biomedical Chemistry, Moscow, Russia, 119121б
| | - Temitope I David
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia, 141701
| | - Abdul-Saleem Amoah
- Phystech School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, Russia, 141701
| | - Tatyana V Korneenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia, 117997
| | - Nikolai A Barlev
- Institute of Cytology, Tikhoretsky Ave 4, Saint Petersburg, Russia, 194064.
- Institute of Biomedical Chemistry, Moscow, Russia, 119121б.
- School of Medicine, Nazarbayev University, 010000, Astana, Kazakhstan.
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2
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van Ravesteyn TW, Arranz Dols M, Pieters W, Dekker M, te Riele H. Extensive trimming of short single-stranded DNA oligonucleotides during replication-coupled gene editing in mammalian cells. PLoS Genet 2020; 16:e1009041. [PMID: 33119594 PMCID: PMC7595315 DOI: 10.1371/journal.pgen.1009041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Accepted: 08/10/2020] [Indexed: 11/19/2022] Open
Abstract
Through transfection of short single-stranded oligodeoxyribonucleotides (ssODNs) small genomic alterations can be introduced into mammalian cells with high precision. ssODNs integrate into the genome during DNA replication, but the resulting heteroduplex is prone to detection by DNA mismatch repair (MMR), which prevents effective gene modification. We have previously demonstrated that the suppressive action of MMR can be avoided when the mismatching nucleotide in the ssODN is a locked nucleic acid (LNA). Here, we reveal that LNA-modified ssODNs (LMOs) are not integrated as intact entities in mammalian cells, but are severely truncated before and after target hybridization. We found that single additional (non-LNA-modified) mutations in the 5’-arm of LMOs influenced targeting efficiencies negatively and activated the MMR pathway. In contrast, additional mutations in the 3’-arm did not affect targeting efficiencies and were not subject to MMR. Even more strikingly, homology in the 3’-arm was largely dispensable for effective targeting, suggestive for extensive 3’-end trimming. We propose a refined model for LMO-directed gene modification in mammalian cells that includes LMO degradation. The first step of many gene editing approaches in mammalian cells is to generate a targeted DNA lesion. By administering a repair template as second step, endogenous DNA repair mechanisms can be misled to introduce specific gene variants. However, subtle gene modification can also be achieved with high precision through a one-action protocol in the absence of DNA breaks. We have shown before that short single-stranded DNA molecules (LMOs) are very useful to introduce and study genetic variants that may predispose patients to cancer. While LMOs are known to integrate into the genome during DNA replication, the precise mechanism is poorly understood. We targeted mouse embryonic stem cells with differently designed LMOs to examine their effectiveness and editing outcomes. Based on these results we conclude that the two LMO termini are processed at different moments during the gene editing process. While the 3’-arm is degraded prior to LMO binding to the target site, the 5’-arm is degraded afterwards. Counterintuitively we also observe that partial degradation of the 3’-arm increases targeting efficiencies. Taken together our data provides novel mechanistic insight into our understanding of replication-coupled gene editing and may guide future LMO design strategies.
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Affiliation(s)
- Thomas W. van Ravesteyn
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Marcos Arranz Dols
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Wietske Pieters
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Marleen Dekker
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
| | - Hein te Riele
- Division of Tumor Biology and Immunology, The Netherlands Cancer Institute, 1066 CX Amsterdam, the Netherlands
- * E-mail:
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3
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Valledor M, Myers RS, Schiller PC. Herpes ICP8 protein stimulates homologous recombination in human cells. PLoS One 2018; 13:e0200955. [PMID: 30110337 PMCID: PMC6093641 DOI: 10.1371/journal.pone.0200955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 07/04/2018] [Indexed: 12/11/2022] Open
Abstract
Recombineering has transformed functional genomic analysis. Genome modification by recombineering using the phage lambda Red homologous recombination protein Beta in Escherichia coli has approached 100% efficiency. While highly efficient in E. coli, recombineering using the Red Synaptase/Exonuclease pair (SynExo) in other organisms declines in efficiency roughly correlating with phylogenetic distance from E. coli. SynExo recombinases are common to double-stranded DNA viruses infecting a variety of organisms, including humans. Human Herpes virus 1 (HHV1) encodes a SynExo comprised of ICP8 synaptase and UL12 exonuclease. In a previous study, the Herpes SynExo was reconstituted in vitro and shown to catalyze a model recombination reaction. Here we describe stimulation of gene targeting to edit a novel fluorescent protein gene in the human genome using ICP8 and compared its efficiency to that of a "humanized" version of Beta protein from phage λ. ICP8 significantly enhanced gene targeting rates in HEK 293T cells while Beta was not only unable to catalyze recombineering but inhibited gene targeting using endogenous recombination functions, despite both synaptases being well-expressed and localized to the nucleus. This proof of concept encourages developing species-specific SynExo recombinases for genome engineering.
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Affiliation(s)
- Melvys Valledor
- Department of Neurology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Richard S. Myers
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, Florida, United States of America
| | - Paul C. Schiller
- Department of Orthopaedics, University of Miami Miller School of Medicine, Miami, Florida, United States of America
- Geriatric Research, Education, and Clinical Center and Research Service, Bruce W. Carter VAMC, Miami, Florida, United States of America
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4
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Tiricz H, Nagy B, Ferenc G, Török K, Nagy I, Dudits D, Ayaydin F. Relaxed chromatin induced by histone deacetylase inhibitors improves the oligonucleotide-directed gene editing in plant cells. JOURNAL OF PLANT RESEARCH 2018; 131:179-189. [PMID: 28836127 DOI: 10.1007/s10265-017-0975-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 07/26/2017] [Indexed: 06/07/2023]
Abstract
Improving efficiency of oligonucleotide-directed mutagenesis (ODM) is a prerequisite for wide application of this gene-editing approach in plant science and breeding. Here we have tested histone deacetylase inhibitor treatments for induction of relaxed chromatin and for increasing the efficiency of ODM in cultured maize cells. For phenotypic assay we produced transgenic maize cell lines expressing the non-functional Green Fluorescent Protein (mGFP) gene carrying a TAG stop codon. These transgenic cells were bombarded with corrective oligonucleotide as editing reagent to recover GFP expression. Repair of green fluorescent protein function was monitored by confocal fluorescence microscopy and flow cytometry was used for quantification of correction events. Sequencing PCR fragments of the GFP gene from corrected cells indicated a nucleotide exchange in the stop codon (TAG) from T to G nucleotide that resulted in the restoration of GFP function. We show that pretreatment of maize cells with sodium butyrate (5-10 mM) and nicotinamide (1-5 mM) as known inhibitors of histone deacetylases can cause elevated chromatin sensitivity to DNase I that was visualized in agarose gels and confirmed by the reduced presence of intact PCR template for the inserted exogenous mGFP gene. Maize cells with more relaxed chromatin could serve as an improved recipient for targeted nucleotide exchange as indicated by an average of 2.67- to 3.62-fold increase in GFP-positive cells. Our results stimulate further studies on the role of the condition of the recipient cells in ODM and testing the application of chromatin modifying agents in other, programmable nuclease-based genome-editing techniques in higher plants.
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Affiliation(s)
- Hilda Tiricz
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Bettina Nagy
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Györgyi Ferenc
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Katalin Török
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - István Nagy
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
- SeqOmics Biotechnology Ltd., Mórahalom, Hungary
| | - Dénes Dudits
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary.
| | - Ferhan Ayaydin
- Institute of Plant Biology, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
- Laboratory of Cellular Imaging, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
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Rivera-Torres N, Kmiec EB. A Standard Methodology to Examine On-site Mutagenicity As a Function of Point Mutation Repair Catalyzed by CRISPR/Cas9 and SsODN in Human Cells. J Vis Exp 2017. [PMID: 28872131 PMCID: PMC5614406 DOI: 10.3791/56195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Combinatorial gene editing using CRISPR/Cas9 and single-stranded oligonucleotides is an effective strategy for the correction of single-base point mutations, which often are responsible for a variety of human inherited disorders. Using a well-established cell-based model system, the point mutation of a single-copy mutant eGFP gene integrated into HCT116 cells has been repaired using this combinatorial approach. The analysis of corrected and uncorrected cells reveals both the precision of gene editing and the development of genetic lesions, when indels are created in uncorrected cells in the DNA sequence surrounding the target site. Here, the specific methodology used to analyze this combinatorial approach to the gene editing of a point mutation, coupled with a detailed experimental strategy to measuring indel formation at the target site, is outlined. This protocol outlines a foundational approach and workflow for investigations aimed at developing CRISPR/Cas9-based gene editing for human therapy. The conclusion of this work is that on-site mutagenesis takes place as a result of CRISPR/Cas9 activity during the process of point mutation repair. This work puts in place a standardized methodology to identify the degree of mutagenesis, which should be an important and critical aspect of any approach destined for clinical implementation.
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Affiliation(s)
- Natalia Rivera-Torres
- Gene Editing Institute, Helen F. Graham Cancer Center and Research Institute, Christiana Care Health Services; Department of Medical Sciences, University of Delaware
| | - Eric B Kmiec
- Gene Editing Institute, Helen F. Graham Cancer Center and Research Institute, Christiana Care Health Services; Department of Medical Sciences, University of Delaware;
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Sauer NJ, Narváez-Vásquez J, Mozoruk J, Miller RB, Warburg ZJ, Woodward MJ, Mihiret YA, Lincoln TA, Segami RE, Sanders SL, Walker KA, Beetham PR, Schöpke CR, Gocal GFW. Oligonucleotide-Mediated Genome Editing Provides Precision and Function to Engineered Nucleases and Antibiotics in Plants. PLANT PHYSIOLOGY 2016; 170:1917-28. [PMID: 26864017 PMCID: PMC4825113 DOI: 10.1104/pp.15.01696] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 02/01/2016] [Indexed: 05/19/2023]
Abstract
Here, we report a form of oligonucleotide-directed mutagenesis for precision genome editing in plants that uses single-stranded oligonucleotides (ssODNs) to precisely and efficiently generate genome edits at DNA strand lesions made by DNA double strand break reagents. Employing a transgene model in Arabidopsis (Arabidopsis thaliana), we obtained a high frequency of precise targeted genome edits when ssODNs were introduced into protoplasts that were pretreated with the glycopeptide antibiotic phleomycin, a nonspecific DNA double strand breaker. Simultaneous delivery of ssODN and a site-specific DNA double strand breaker, either transcription activator-like effector nucleases (TALENs) or clustered, regularly interspaced, short palindromic repeats (CRISPR/Cas9), resulted in a much greater targeted genome-editing frequency compared with treatment with DNA double strand-breaking reagents alone. Using this site-specific approach, we applied the combination of ssODN and CRISPR/Cas9 to develop an herbicide tolerance trait in flax (Linum usitatissimum) by precisely editing the 5'-ENOLPYRUVYLSHIKIMATE-3-PHOSPHATE SYNTHASE (EPSPS) genes. EPSPS edits occurred at sufficient frequency that we could regenerate whole plants from edited protoplasts without employing selection. These plants were subsequently determined to be tolerant to the herbicide glyphosate in greenhouse spray tests. Progeny (C1) of these plants showed the expected Mendelian segregation of EPSPS edits. Our findings show the enormous potential of using a genome-editing platform for precise, reliable trait development in crop plants.
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LNA modification of single-stranded DNA oligonucleotides allows subtle gene modification in mismatch-repair-proficient cells. Proc Natl Acad Sci U S A 2016; 113:4122-7. [PMID: 26951689 DOI: 10.1073/pnas.1513315113] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Synthetic single-stranded DNA oligonucleotides (ssODNs) can be used to generate subtle genetic modifications in eukaryotic and prokaryotic cells without the requirement for prior generation of DNA double-stranded breaks. However, DNA mismatch repair (MMR) suppresses the efficiency of gene modification by >100-fold. Here we present a commercially available ssODN design that evades MMR and enables subtle gene modification in MMR-proficient cells. The presence of locked nucleic acids (LNAs) in the ssODNs at mismatching bases, or also at directly adjacent bases, allowed 1-, 2-, or 3-bp substitutions in MMR-proficient mouse embryonic stem cells as effectively as in MMR-deficient cells. Additionally, in MMR-proficient Escherichia coli, LNA modification of the ssODNs enabled effective single-base-pair substitution. In vitro, LNA modification of mismatches precluded binding of purified E. coli MMR protein MutS. These findings make ssODN-directed gene modification particularly well suited for applications that require the evaluation of a large number of sequence variants with an easy selectable phenotype.
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8
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Sauer NJ, Mozoruk J, Miller RB, Warburg ZJ, Walker KA, Beetham PR, Schöpke CR, Gocal GFW. Oligonucleotide-directed mutagenesis for precision gene editing. PLANT BIOTECHNOLOGY JOURNAL 2016; 14:496-502. [PMID: 26503400 PMCID: PMC5057361 DOI: 10.1111/pbi.12496] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 09/18/2015] [Accepted: 09/23/2015] [Indexed: 05/23/2023]
Abstract
Differences in gene sequences, many of which are single nucleotide polymorphisms, underlie some of the most important traits in plants. With humanity facing significant challenges to increase global agricultural productivity, there is an urgent need to accelerate the development of these traits in plants. oligonucleotide-directed mutagenesis (ODM), one of the many tools of Cibus' Rapid Trait Development System (RTDS(™) ) technology, offers a rapid, precise and non-transgenic breeding alternative for trait improvement in agriculture to address this urgent need. This review explores the application of ODM as a precision genome editing technology, with emphasis on using oligonucleotides to make targeted edits in plasmid, episomal and chromosomal DNA of bacterial, fungal, mammalian and plant systems. The process of employing ODM by way of RTDS technology has been improved in many ways by utilizing a fluorescence conversion system wherein a blue fluorescent protein (BFP) can be changed to a green fluorescent protein (GFP) by editing a single nucleotide of the BFP gene (CAC→TAC; H66 to Y66). For example, dependent on oligonucleotide length, applying oligonucleotide-mediated technology to target the BFP transgene in Arabidopsis thaliana protoplasts resulted in up to 0.05% precisely edited GFP loci. Here, the development of traits in commercially relevant plant varieties to improve crop performance by genome editing technologies such as ODM, and by extension RTDS, is reviewed.
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Xu K, Stewart AF, Porter AC. Stimulation of oligonucleotide-directed gene correction by Redβ expression and MSH2 depletion in human HT1080 cells. Mol Cells 2015; 38:33-9. [PMID: 25431426 PMCID: PMC4314130 DOI: 10.14348/molcells.2015.2163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 10/14/2014] [Accepted: 10/15/2014] [Indexed: 01/30/2023] Open
Abstract
The correction of disease-causing mutations by single-strand oligonucleotide-templated DNA repair (ssOR) is an attractive approach to gene therapy, but major improvements in ssOR efficiency and consistency are needed. The mechanism of ssOR is poorly understood but may involve annealing of oligonucleotides to transiently exposed single-stranded regions in the target duplex. In bacteria and yeast it has been shown that ssOR is promoted by expression of Redβ, a single-strand DNA annealing protein from bacteriophage lambda. Here we show that Redβ expression is well tolerated in a human cell line where it consistently promotes ssOR. By use of short interfering RNA, we also show that ssOR is stimulated by the transient depletion of the endogenous DNA mismatch repair protein MSH2. Furthermore, we find that the effects of Redβ expression and MSH2 depletion on ssOR can be combined with a degree of cooperativity. These results suggest that oligonucleotide annealing and mismatch recognition are distinct but interdependent events in ssOR that can be usefully modulated in gene correction strategies.
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Affiliation(s)
- Ke Xu
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenviroment, Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin 300052,
China
- Gene Targeting Group, Department of Hematology, Faculty of Medicine, Imperial College London, London W12 0NN,
UK
| | - A. Francis Stewart
- Genomics, Bio Innovations Zentrum, Technische Universitaet Dresden, 01307 Dresden,
Germany
| | - Andrew C.G. Porter
- Gene Targeting Group, Department of Hematology, Faculty of Medicine, Imperial College London, London W12 0NN,
UK
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Dernigoghossian M, Krigel A, Behar-Cohen F, Andrieu-Soler C. Method for retinal gene repair in neonatal mouse. Methods Mol Biol 2014; 1114:387-98. [PMID: 24557917 DOI: 10.1007/978-1-62703-761-7_25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gene correction at the site of the mutation in the chromosome is the absolute way to really cure a genetic disease. The oligonucleotide (ODN)-mediated gene repair technology uses an ODN perfectly complementary to the genomic sequence except for a mismatch at the base that is mutated. The endogenous repair machinery of the targeted cell then mediates substitution of the desired base in the gene, resulting in a completely normal sequence. Theoretically, it avoids potential gene silencing or random integration associated with common viral gene augmentation approaches and allows an intact regulation of expression of the therapeutic protein. The eye is a particularly attractive target for gene repair because of its unique features (small organ, easily accessible, low diffusion into systemic circulation). Moreover therapeutic effects on visual impairment could be obtained with modest levels of repair. This chapter describes in details the optimized method to target active ODNs to the nuclei of photoreceptors in neonatal mouse using (1) an electric current application at the eye surface (saline transpalpebral iontophoresis), (2) combined with an intravitreous injection of ODNs, as well as the experimental methods for (3) the dissection of adult neural retinas, (4) their immuno-labelling, and (5) flat-mounting for direct observation of photoreceptor survival, a relevant criteria of treatment outcomes for retinal degeneration.
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Affiliation(s)
- Marilyn Dernigoghossian
- INSERM, Centre de Recherche des Cordeliers, Université René Descartes Sorbonne Paris Cité, Paris, France
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Wang X, Wang Y, Huang H, Chen B, Chen X, Hu J, Chang T, Lin RJ, Yee JK. Precise gene modification mediated by TALEN and single-stranded oligodeoxynucleotides in human cells. PLoS One 2014; 9:e93575. [PMID: 24691488 PMCID: PMC3972112 DOI: 10.1371/journal.pone.0093575] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 03/05/2014] [Indexed: 11/18/2022] Open
Abstract
The development of human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) facilitates in vitro studies of human disease mechanisms, speeds up the process of drug screening, and raises the feasibility of using cell replacement therapy in clinics. However, the study of genotype-phenotype relationships in ESCs or iPSCs is hampered by the low efficiency of site-specific gene editing. Transcription activator-like effector nucleases (TALENs) spurred interest due to the ease of assembly, high efficiency and faithful gene targeting. In this study, we optimized the TALEN design to maximize its genomic cutting efficiency. We showed that using optimized TALENs in conjunction with single-strand oligodeoxynucleotide (ssODN) allowed efficient gene editing in human cells. Gene mutations and gene deletions for up to 7.8 kb can be accomplished at high efficiencies. We established human tumor cell lines and H9 ESC lines with homozygous deletion of the microRNA-21 (miR-21) gene and miR-9-2 gene. These cell lines provide a robust platform to dissect the roles these genes play during cell differentiation and tumorigenesis. We also observed that the endogenous homologous chromosome can serve as a donor template for gene editing. Overall, our studies demonstrate the versatility of using ssODN and TALEN to establish genetically modified cells for research and therapeutic application.
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Affiliation(s)
- Xiaoling Wang
- Department of Virology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
| | - Yingjia Wang
- Department of Virology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang, China
| | - He Huang
- Bone Marrow Transplantation Center, The First Affiliated Hospital, Zhejiang University, Hangzhou, Zhejiang, China
| | - Buyuan Chen
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
- Department of Hematology, Union Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Xinji Chen
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
- Department of Hematology, Union Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Jianda Hu
- Department of Hematology, Union Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Tammy Chang
- Department of Virology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
| | - Ren-Jang Lin
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
| | - Jiing-Kuan Yee
- Department of Virology, Beckman Research Institute of City of Hope, Duarte, California, United States of America
- * E-mail:
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12
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Livingston P, Strouse B, Perry H, Borjigin M, Bialk P, Kmiec EB. Oligonucleotide delivery by nucleofection does not rescue the reduced proliferation phenotype of gene-edited cells. Nucleic Acid Ther 2012; 22:405-13. [PMID: 23072627 DOI: 10.1089/nat.2012.0374] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Gene editing using single-stranded oligonucleotides (ODNs) can be used to reverse or create a single base mutation in mammalian cells. This approach could be used to treat genetic diseases caused, at least in part, by a nucleotide substitution. The technique could also be used as a tool to establish single base polymorphisms at multiple sites and thus aid in creating cell lines that can be used to define the basis for drug resistance in human cells. A troubling outcome of the gene-editing reaction is the effect on normal growth of cells that have undergone nucleotide exchange. In this work, we attempt to overcome this reduced proliferation phenotype by changing the method by which the ODN is introduced into the target cell. Using a series of assays that measure gene editing, DNA damage response, and cell viability, we report that chemically modified ODNs, the most active form of ODN for gene editing, can be used successfully if introduced into the cell by the method of nucleofection. Unlike electroporation, which has been used as the standard mode of ODN delivery, one new result is that nucleofection does not induce a dramatic loss of viability within the first 24 hours after the start of gene editing. In addition, and importantly, ODNs introduced to the cell by nucleofection do not activate the DNA damage response pathway as dramatically as ODNs introduced by electroporation. These 2 novel findings are encouraging for the application of gene editing in other systems. However, reduced proliferation phenotype is still observed when the population of corrected cells is monitored out to 8 days, and thus, delivery by nucleofection does not solve the proliferation problem encountered by cells bearing an edited gene.
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Affiliation(s)
- Paula Livingston
- Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, West Virginia, USA
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13
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DNA damage response pathway and replication fork stress during oligonucleotide directed gene editing. MOLECULAR THERAPY. NUCLEIC ACIDS 2012; 1:e18. [PMID: 23343929 PMCID: PMC3381643 DOI: 10.1038/mtna.2012.9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Single-stranded DNA oligonucleotides (ODNs) can be used to direct the exchange of nucleotides in the genome of mammalian cells in a process known as gene editing. Once refined, gene editing should become a viable option for gene therapy and molecular medicine. Gene editing is regulated by a number of DNA recombination and repair pathways whose natural activities often lead to single- and double-stranded DNA breaks. It has been previously shown that introduction of a phosphorotioated ODN, designed to direct a gene-editing event, into cells results in the activation of γH2AX, a well-recognized protein biomarker for double-stranded DNA breakage. Using a single copy, integrated mutant enhanced green fluorescent protein (eGFP) gene as our target, we now demonstrate that several types of ODNs, capable of directing gene editing, also activate the DNA damage response and the post-translational modification of proliferating cell nuclear antigen (PCNA), a signature modification of replication stress. We find that the gene editing reaction itself leads to transient DNA breakage, perhaps through replication fork collapse. Unmodified specific ODNs elicit a lesser degree of replication stress than their chemically modified counterparts, but are also less active in gene editing. Modified phosphothioate oligonucleotides (PTOs) are detrimental irrespective of the DNA sequence. Such collateral damage may prove problematic for proliferation of human cells genetically modified by gene editing.
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Papaioannou I, Simons JP, Owen JS. Oligonucleotide-directed gene-editing technology: mechanisms and future prospects. Expert Opin Biol Ther 2012; 12:329-42. [PMID: 22321001 DOI: 10.1517/14712598.2012.660522] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION Gene editing, as defined here, uses short synthetic oligonucleotides to introduce small, site-specific changes into mammalian genomes, including repair of genetic point mutations. Early RNA-DNA oligonucleotides (chimeraplasts) were problematic, but application of single-stranded all-DNA molecules (ssODNs) has matured the technology into a reproducible tool with therapeutic potential. AREAS COVERED The review illustrates how gene-editing mechanisms are linked to DNA repair systems and DNA replication, and explains that while homologous recombination (HR) and nucleotide excision repair (NER) are implicated, the mismatch repair (MMR) system is inhibitory. Although edited cells often arrest in late S-phase or G2-phase, alternative ssODN chemistries can improve editing efficiency and cell viability. The final section focuses on the exciting tandem use of ssODNs with zinc finger nucleases to achieve high frequency genome editing. EXPERT OPINION For a decade, changing the genetic code of cells via ssODNs was largely done in reporter gene systems to optimize methods and as proof-of-principle. Today, editing endogenous genes is advancing, driven by a clearer understanding of mechanisms, by effective ssODN designs and by combination with engineered endonuclease technologies. Success is becoming routine in vitro and ex vivo, which includes editing embryonic stem (ES) and induced pluripotent stem (iPS) cells, suggesting that in vivo organ gene editing is a future option.
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Affiliation(s)
- Ioannis Papaioannou
- UCL Medical School, Division of Medicine (Upper 3rd Floor), Royal Free Campus, Rowland Hill Street, London NW3 2PF, UK
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15
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Falgowski K, Falgowski C, York-Vickers C, Kmiec EB. Strand bias influences the mechanism of gene editing directed by single-stranded DNA oligonucleotides. Nucleic Acids Res 2011; 39:4783-94. [PMID: 21343181 PMCID: PMC3113578 DOI: 10.1093/nar/gkr061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Gene editing directed by modified single-stranded DNA oligonucleotides has been used to alter a single base pair in a variety of biological systems. It is likely that gene editing is facilitated by the direct incorporation of the oligonucleotides via replication and/or by direct conversion, most likely through the DNA mismatch repair pathway. The phenomenon of strand bias, however, as well as its importance to the gene editing reaction itself, has yet to be elucidated in terms of mechanism. We have taken a reductionist approach by using a genetic readout in Eschericha coli and a plasmid-based selectable system to evaluate the influence of strand bias on the mechanism of gene editing. We show that oligonucleotides (ODNs) designed to anneal to the lagging strand generate 100-fold greater 'editing' efficiency than 'those that anneal to' the leading strand. The majority of editing events (∼70%) occur by the incorporation of the ODN during replication within the lagging strand. Conversely, ODNs that anneal to the leading strand generate fewer editing events although this event may follow either the incorporation or direct conversion pathway. In general, the influence of DNA replication is independent of which ODN is used suggesting that the importance of strand bias is a reflection of the underlying mechanism used to carry out gene editing.
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Affiliation(s)
- Kerry Falgowski
- Marshall Institute for Interdisciplinary Research, Marshall University, Robert C. Byrd Biotechnology Science Center, 1700 Third Avenue, Suite 220, Huntington, WV 25755, USA
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16
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Pakpour N, Cheung KW, Souvannaseng L, Concordet JP, Luckhart S. Transfection and mutagenesis of target genes in mosquito cells by locked nucleic acid-modified oligonucleotides. J Vis Exp 2010:2355. [PMID: 21206476 DOI: 10.3791/2355] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Plasmodium parasites, the causative agent of malaria, are transmitted through the bites of infected Anopheles mosquitoes resulting in over 250 million new infections each year. Despite decades of research, there is still no vaccine against malaria, highlighting the need for novel control strategies. One innovative approach is the use of genetically modified mosquitoes to effectively control malaria parasite transmission. Deliberate alterations of cell signaling pathways in the mosquito, via targeted mutagenesis, have been found to regulate parasite development (1). From these studies, we can begin to identify potential gene targets for transformation. Targeted mutagenesis has traditionally relied upon the homologous recombination between a target gene and a large DNA molecule. However, the construction and use of such complex DNA molecules for generation of stably transformed cell lines is costly, time consuming and often inefficient. Therefore, a strategy using locked nucleic acid-modified oligonucleotides (LNA-ONs) provides a useful alternative for introducing artificial single nucleotide substitutions into episomal and chromosomal DNA gene targets (reviewed in (2)). LNA-ON-mediated targeted mutagenesis has been used to introduce point mutations into genes of interest in cultured cells of both yeast and mice (3,4). We show here that LNA-ONs can be used to introduce a single nucleotide change in a transfected episomal target that results in a switch from blue fluorescent protein (BFP) expression to green fluorescent protein (GFP) expression in both Anopheles gambiae and Anopheles stephensi cells. This conversion demonstrates for the first time that effective mutagenesis of target genes in mosquito cells can be mediated by LNA-ONs and suggests that this technique may be applicable to mutagenesis of chromosomal targets in vitro and in vivo.
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Affiliation(s)
- Nazzy Pakpour
- Department of Medical Microbiology and Immunology, University of California, Davis, USA
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17
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Aarts M, te Riele H. Progress and prospects: oligonucleotide-directed gene modification in mouse embryonic stem cells: a route to therapeutic application. Gene Ther 2010; 18:213-9. [PMID: 21160530 DOI: 10.1038/gt.2010.161] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Gene targeting by single-stranded oligodeoxyribonucleotides (ssODNs) is a promising technique for introducing site-specific sequence alterations without affecting the genomic organization of the target locus. Here, we discuss the significant progress that has been made over the last 5 years in unraveling the mechanisms and reaction parameters underlying ssODN-mediated gene targeting. We will specifically focus on ssODN-mediated gene targeting in murine embryonic stem cells (ESCs) and the impact of the DNA mismatch repair (MMR) system on the targeting process. Implications of novel findings for routine application of ssODN-mediated gene targeting and challenges that need to be overcome for future therapeutic applications are highlighted.
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Affiliation(s)
- M Aarts
- Division of Molecular Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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18
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Aarts M, te Riele H. Subtle gene modification in mouse ES cells: evidence for incorporation of unmodified oligonucleotides without induction of DNA damage. Nucleic Acids Res 2010; 38:6956-67. [PMID: 20601408 PMCID: PMC2978364 DOI: 10.1093/nar/gkq589] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Gene targeting by single-stranded oligodeoxyribonucleotides (ssODNs) is a promising tool for site-specific gene modification in mouse embryonic stem cells (ESCs). We have developed an ESC line carrying a mutant EGFP reporter gene to monitor gene correction events shortly after exposure to ssODNs. We used this system to compare the appearance and fate of cells corrected by sense or anti-sense ssODNs. The slower appearance of green fluorescent cells with sense ssODNs as compared to anti-sense ssODNs is consistent with physical incorporation of the ssODN into the genome. Thus, the supremacy of anti-sense ssODNs, previously reported by others, may be an artefact of early readout of the EGFP reporter. Importantly, gene correction by unmodified ssODNs only mildly affected the viability of targeted cells and did not induce genomic DNA double-stranded breaks (DSBs). In contrast, ssODNs that were end-protected by phosphorothioate (PTO) linkages caused increased H2AX phosphorylation and impaired cell cycle progression in both corrected and non-corrected cells due to induction of genomic DSBs. Our results demonstrate that the use of unmodified rather than PTO end-protected ssODNs allows stable gene modification without compromising the genomic integrity of the cell, which is crucial for application of ssODN-mediated gene targeting in (embryonic) stem cells.
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Affiliation(s)
- Marieke Aarts
- Division of Molecular Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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19
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Bertoni C, Rustagi A, Rando TA. Enhanced gene repair mediated by methyl-CpG-modified single-stranded oligonucleotides. Nucleic Acids Res 2010; 37:7468-82. [PMID: 19854937 PMCID: PMC2794159 DOI: 10.1093/nar/gkp757] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Gene editing mediated by oligonucleotides has been shown to induce stable single base alterations in genomic DNA in both prokaryotic and eukaryotic organisms. However, the low frequencies of gene repair have limited its applicability for both basic manipulation of genomic sequences and for the development of therapeutic approaches for genetic disorders. Here, we show that single-stranded oligodeoxynucleotides (ssODNs) containing a methyl-CpG modification and capable of binding to the methyl-CpG binding domain protein 4 (MBD4) are able to induce >10-fold higher levels of gene correction than ssODNs lacking the specific modification. Correction was stably inherited through cell division and was confirmed at the protein, transcript and genomic levels. Downregulation of MBD4 expression using RNAi prevented the enhancement of gene correction efficacy obtained using the methyl-CpG-modified ssODN, demonstrating the specificity of the repair mechanism being recruited. Our data demonstrate that efficient manipulation of genomic targets can be achieved and controlled by the type of ssODN used and by modulation of the repair mechanism involved in the correction process. This new generation of ssODNs represents an important technological advance that is likely to have an impact on multiple applications, especially for gene therapy where permanent correction of the genetic defect has clear advantages over viral and other nonviral approaches currently being tested.
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Affiliation(s)
- Carmen Bertoni
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA 94305, USA.
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20
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Katada H, Chen HJ, Shigi N, Komiyama M. Homologous recombination in human cells using artificial restriction DNA cutter. Chem Commun (Camb) 2009:6545-7. [PMID: 19865644 DOI: 10.1039/b912030k] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The double strand break induced by an artificial restriction DNA cutter (ARCUT) was successfully repaired in human cells with high frequencies through homologous recombination.
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Affiliation(s)
- Hitoshi Katada
- Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, 153-8904 Tokyo, Japan
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21
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Abstract
Gene targeting by single-stranded oligodeoxyribonucleotides (ssODNs) is emerging as a powerful tool for the introduction of subtle gene modifications in mouse embryonic stem (ES) cells and the generation of mutant mice. Here, we have studied the role of ssODN composition, transcription and replication of the target locus, and DNA repair pathways to gain more insight into the parameters governing ssODN-mediated gene targeting in mouse ES cells. We demonstrated that unmodified ssODNs of 35–40 nt were most efficient in correcting a chromosomally integrated mutant neomycin reporter gene. Addition of chemical modifications did not further enhance the efficacy of these ssODNs. The observed strand bias was not affected by transcriptional activity and may rather be caused by the different accessibility of the DNA strands during DNA replication. Consistently, targeting frequencies were enhanced when cells were treated with hydroxyurea to reduce the rate of replication fork progression. Transient down-regulation of various DNA repair genes by RNAi had no effect on the targeting frequency. Taken together, our data suggest that ssODN-mediated gene targeting occurs within the context of a replication fork. This implies that any given genomic sequence, irrespective of transcriptional status, should be amenable to ssODN-mediated gene targeting. The ability of ES cells to differentiate into various cell types after ssODN-mediated gene targeting may offer opportunities for future therapeutic applications.
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Affiliation(s)
- Marieke Aarts
- Division of Molecular Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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22
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Wuepping M, Kenner O, Hegele H, Schwandt S, Kaufmann D. Higher efficiency of thymine-adenine clamp-modified single-stranded oligonucleotides in targeted nucleotide sequence correction is not correlated with lower intracellular degradation. Hum Gene Ther 2009; 20:283-7. [PMID: 19061415 DOI: 10.1089/hum.2008.138] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Specific single-stranded oligonucleotides can induce targeted nucleotide sequence correction in eukaryotic genes in vitro and in vivo. Our model for investigating the reasons for the low correction rates achieved by this method is the correction of a point mutation in the hypoxanthine-guanine phosphoribosyltransferase gene (hprt) in the cell line V79-151. Using single-stranded phosphorothioate-modified oligonucleotides, the correction rates of this hprt mutation were low but always reproducible. One reason for low exchange rates may be fast intracellular degradation of the oligonucleotides. Therefore we compared the exchange rates of different 3' and 5' end-modified oligonucleotides with their degradation rates. Thymine-adenine (TA) repeat (clamp)-modified oligonucleotides showed higher correction rates than those with a guanine-cytosine (GC) clamp and 5' clamps induced higher correction rates than clamps at the 3' end. Experiments on the stability of the most effective 5'-TA and 3'-TA clamp-modified oligonucleotide indicated rapid cleavage and the occurrence of shortened oligonucleotides in the presence of cytoplasmic and nuclear extracts. The phosphorothioate-modified oligonucleotides were more stable, but their correction rates were lower. We suggest that there is no direct correlation between the biological stability of the full-length oligonucleotides and the exchange rates achieved.
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Affiliation(s)
- M Wuepping
- Institute of Human Genetics, University of Ulm, Albert-Einstein-Allee 11, Ulm, Germany
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23
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Papaioannou I, Disterer P, Owen JS. Use of internally nuclease-protected single-strand DNA oligonucleotides and silencing of the mismatch repair protein, MSH2, enhances the replication of corrected cells following gene editing. J Gene Med 2009; 11:267-74. [PMID: 19153972 DOI: 10.1002/jgm.1296] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Gene editing is potentially a powerful technology for introducing genetic changes by using short single-stranded DNA oligonucleotides (ssODNs). However, their efficiency is reduced by the mismatch repair system, especially MSH2, which may suppress gene editing, although findings vary depending on readout and type of oligonucleotide used. Additionally, successfully edited cells are reported to arrest at the S- or G2-phase. In the present study, we evaluate whether a novel ssODN design and down-regulation of MSH2 expression allows the isolation of replicating gene-edited cells. METHODS Cultured Chinese hamster ovary cells expressing mutated enhanced green fluorescent protein were targeted with ssODNs of varying design, all capable of restoring fluorescence, which allows the monitoring of correction events by flow cytometry. Converted cells were isolated by cell sorting and grown to determine colony formation efficiencies. MSH2 expression was suppressed with small interfering RNA and the cell cycle distribution of cells transfected with ssODN was quantified by flow cytometry, following propidium iodide or DRAQ5 staining. RESULTS Although efficiency was higher using ssODN end-protected with phosphorothioate, the potential of edited cells to form colonies was lower than those targeted with unmodified ssODN. We established that ssODN transfection itself perturbs the cell cycle and that MSH2 gene silencing increases correction efficiency. In both cases, however, the effect was dependent on the positioning of the protected nucleotides. Importantly, when internally protected ssODN was used in combination with MSH2 suppression, a higher proportion of G1-phase corrected cells was observed 48-64 h after transfection. CONCLUSIONS Use of internally protected ssODN and downregulating cellular MSH2 activity may facilitate isolation of viable, actively replicating gene-edited cells.
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Affiliation(s)
- Ioannis Papaioannou
- Department of Medicine, Royal Free and University College Medical School, Royal Free Campus, London, UK
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24
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Robertson KL, Thach DC. LNA flow-FISH: a flow cytometry-fluorescence in situ hybridization method to detect messenger RNA using locked nucleic acid probes. Anal Biochem 2009; 390:109-14. [PMID: 19393610 DOI: 10.1016/j.ab.2009.04.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 04/15/2009] [Accepted: 04/16/2009] [Indexed: 10/20/2022]
Abstract
We present a novel method using flow cytometry-fluorescence in situ hybridization (flow-FISH) to detect specific messenger RNA (mRNA) in suspended cells using locked nucleic acid (LNA)-modified oligonucleotide probes. beta-Actin mRNA was targeted in whole A549 epithelial cells by hybridization with a biotinylated, LNA-modified probe. The LNA bound to beta-actin was then stained using phycoerythrin-conjugated streptavidin and detected by flow cytometry. Shifts in fluorescence signal intensity between the beta-actin LNA probe and a biotinylated, nonspecific control LNA were used to determine optimal conditions for this type of flow-FISH. Multiple conditions for permeabilization and hybridization were tested, and it was found that conditions using 3 microg/ml of proteinase K for permeabilization and 90 min hybridization at 60 degrees C with buffer containing 50% formamide allow cells containing the LNA-bound mRNA to be detected and differentiated from the control LNA with high confidence (< 14% overlap between curves). This combined method, called LNA flow-FISH, can be used for detection and quantification of other RNA species as well as for telomerase measurement and detection.
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Affiliation(s)
- Kelly L Robertson
- Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, Washington, DC 20375, USA.
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25
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A comparison of synthetic oligodeoxynucleotides, DNA fragments and AAV-1 for targeted episomal and chromosomal gene repair. BMC Biotechnol 2009; 9:35. [PMID: 19379497 PMCID: PMC2676283 DOI: 10.1186/1472-6750-9-35] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Accepted: 04/20/2009] [Indexed: 12/14/2022] Open
Abstract
Background Current strategies for gene therapy of inherited diseases consist in adding functional copies of the gene that is defective. An attractive alternative to these approaches would be to correct the endogenous mutated gene in the affected individual. This study presents a quantitative comparison of the repair efficiency using different forms of donor nucleic acids, including synthetic DNA oligonucleotides, double stranded DNA fragments with sizes ranging from 200 to 2200 bp and sequences carried by a recombinant adeno-associated virus (rAAV-1). Evaluation of each gene repair strategy was carried out using two different reporter systems, a mutated eGFP gene or a dual construct with a functional eGFP and an inactive luciferase gene, in several different cell systems. Gene targeting events were scored either following transient co-transfection of reporter plasmids and donor DNAs, or in a system where a reporter construct was stably integrated into the chromosome. Results In both episomal and chromosomal assays, DNA fragments were more efficient at gene repair than oligonucleotides or rAAV-1. Furthermore, the gene targeting frequency could be significantly increased by using DNA repair stimulating drugs such as doxorubicin and phleomycin. Conclusion Our results show that it is possible to obtain repair frequencies of 1% of the transfected cell population under optimized transfection protocols when cells were pretreated with phleomycin using rAAV-1 and dsDNA fragments.
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26
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Triplex-forming oligonucleotide-orthophenanthroline conjugates for efficient targeted genome modification. Proc Natl Acad Sci U S A 2008; 105:9576-81. [PMID: 18599454 DOI: 10.1073/pnas.0710433105] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The inefficiency of gene modification by homologous recombination can be overcome by the introduction of a double-strand break (DSB) in the target. Engineering the endonucleases needed, however, remains a challenging task that limits widespread application of nuclease-driven gene modification. We report here that conjugates of orthophenanthroline (OP), a DNA cleaving molecule, and triplex-forming oligonucleotides (TFOs), known to bind specific DNA sequences, are synthetic nucleases efficient at stimulating targeted genome modification. We show that in cultured cells, OP-TFO conjugates induce targeted DSBs. An OP-TFO with a unique target was highly efficient, and mutations at the target site were found in approximately 10% of treated cells, including small deletions most likely introduced during DSB repair by nonhomologous end joining. Importantly, we found that when homologous donor DNA was cotransfected, targeted gene modification took place in >1.5% of treated cells. Because triplex-forming sequences are frequent in human and mouse genes, OP-TFO conjugates therefore constitute an important class of site-specific nucleases for targeted gene modification. Harnessing DNA-damaging molecules to predetermined genomic sites, as achieved here, should also provide inroads into mechanisms of DNA repair and cancer.
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Vassanelli S, Bandiera L, Borgo M, Cellere G, Santoni L, Bersani C, Salamon M, Zaccolo M, Lorenzelli L, Girardi S, Maschietto M, Dal Maschio M, Paccagnella A. Space and time-resolved gene expression experiments on cultured mammalian cells by a single-cell electroporation microarray. N Biotechnol 2008; 25:55-67. [PMID: 18504020 DOI: 10.1016/j.nbt.2008.03.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2007] [Revised: 02/07/2008] [Accepted: 03/03/2008] [Indexed: 02/04/2023]
Abstract
Single-cell experiments represent the next frontier for biochemical and gene expression research. Although bulk-scale methods averaging populations of cells have been traditionally used to investigate cellular behavior, they mask individual cell features and can lead to misleading or insufficient biological results. We report on a single-cell electroporation microarray enabling the transfection of pre-selected individual cells at different sites within the same culture (space-resolved), at arbitrarily chosen time points and even sequentially to the same cells (time-resolved). Delivery of impermeant molecules by single-cell electroporation was first proven to be finely tunable by acting on the electroporation protocol and then optimized for transfection of nucleic acids into Chinese Hamster Ovary (CHO-K1) cells. We focused on DNA oligonucleotides (ODNs), short interfering RNAs (siRNAs), and DNA plasmid vectors, thus providing a versatile and easy-to-use platform for time-resolved gene expression experiments in single mammalian cells.
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Affiliation(s)
- S Vassanelli
- University of Padova, Department of Human Anatomy and Physiology, Section of Physiology, via Marzolo 3 - 35131, Padova, Italy.
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28
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Simon P, Cannata F, Concordet JP, Giovannangeli C. Targeting DNA with triplex-forming oligonucleotides to modify gene sequence. Biochimie 2008; 90:1109-16. [PMID: 18460344 DOI: 10.1016/j.biochi.2008.04.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2007] [Accepted: 04/14/2008] [Indexed: 12/19/2022]
Abstract
Molecules that interact with DNA in a sequence-specific manner are attractive tools for manipulating gene sequence and expression. For example, triplex-forming oligonucleotides (TFOs), which bind to oligopyrimidine.oligopurine sequences via Hoogsteen hydrogen bonds, have been used to inhibit gene expression at the DNA level as well as to induce targeted mutagenesis in model systems. Recent advances in using oligonucleotides and analogs to target DNA in a sequence-specific manner will be discussed. In particular, chemical modification of TFOs has been used to improve binding to chromosomal target sequences in living cells. Various oligonucleotide analogs have also been found to expand the range of sequences amenable to manipulation, including so-called "Zorro" locked nucleic acids (LNAs) and pseudo-complementary peptide nucleic acids (pcPNAs). Finally, we will examine the potential of TFOs for directing targeted gene sequence modification and propose that synthetic nucleases, based on conjugation of sequence-specific DNA ligands to DNA damaging molecules, are a promising alternative to protein-based endonucleases for targeted gene sequence modification.
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Affiliation(s)
- Philippe Simon
- Laboratoire de Biophysique, Muséum National d'Histoire Naturelle, USM 503, 43 rue Cuvier, 75005 Paris, France
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29
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Kobayashi K, Era T, Takebe A, Jakt LM, Nishikawa SI. ARID3B induces malignant transformation of mouse embryonic fibroblasts and is strongly associated with malignant neuroblastoma. Cancer Res 2007; 66:8331-6. [PMID: 16951138 DOI: 10.1158/0008-5472.can-06-0756] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
ARID3B, a member of the AT-rich interaction domain (ARID) family of proteins, plays an essential role in the survival of neural crest during embryogenesis. Here, we report evidence that ARID3B is involved in the development of malignant neuroblastoma, a childhood tumor derived from neural crest. (a) ARID3B is expressed by all five cell lines derived from neuroblastoma tested by us. (b) Analysis of published DNA microarray data of fresh neuroblastoma tumors showed that ARID3B is expressed in 80% of stage IV tumors, whereas only in 9% of stage I-III+IVs tumors. (c) In vitro growth of several neuroblastoma cell lines is suppressed significantly by antisense as well as siRNA treatment. (d) An increase of the ARID3B expression level by transfection in the SY5Y neuroblastoma cell line enhances the malignancy in tumor growth assays in nu/nu mice. (e) ARID3B by itself can immortalize mouse embryonic fibroblasts (MEFs) in vitro and confers malignancy to MEF when transfected together with MYCN, the best characterized oncogene for neuroblastoma. Thus, ARID3B seems to play a key role in the malignant transformation of neuroblastoma and may serve not only as a marker of malignancy but also as a potential target for cancer therapy of stage IV neuroblastoma for which there is currently no effective treatment available.
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Affiliation(s)
- Kenichiro Kobayashi
- Laboratory for Stem Cell Biology, RIKEN Center for Development Biology, Graduate School of Medicine, Kobe University, Kobe, Hyogo, Japan
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Kaur H, Babu BR, Maiti S. Perspectives on chemistry and therapeutic applications of Locked Nucleic Acid (LNA). Chem Rev 2007; 107:4672-97. [PMID: 17944519 DOI: 10.1021/cr050266u] [Citation(s) in RCA: 231] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Harleen Kaur
- Institute of Genomics and Integrative Biology, CSIR, Mall Road, Delhi 110 007, India
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31
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de Piédoue G, Andrieu-Soler C, Concordet JP, Maurisse R, Sun JS, Lopez B, Kuzniak I, Leboulch P, Feugeas JP. Targeted gene correction with 5' acridine-oligonucleotide conjugates. Oligonucleotides 2007; 17:258-63. [PMID: 17638529 DOI: 10.1089/oli.2007.0074] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Single-stranded oligonucleotides (SSOs) mediate gene repair of punctual chromosomal mutations at a low frequency. We hypothesized that enhancement of DNA binding affinity of SSOs by intercalating agents may increase the number of corrected cells. Several biochemical modifications of SSOs were tested for their capability to correct a chromosomally integrated and mutated GFP reporter gene in human 293 cells. SSOs of 25 nucleotide length conjugated with acridine at their 5' end increased the efficiency of gene correction up to 10-fold compared to nonmodified SSOs. Acridine and psoralen conjugates were both evaluated, and acridine-modified SSOs were the most effective. Conjugation with acridine at the 3' end of the SSO inhibited gene correction, whereas flanking the SSO by acridine on both sides provided an intermediate level of correction. These results suggest that increasing the stability of hybridization between SSO and its target without hampering a 3' extension improves gene targeting, in agreement with the "annealing-integration" model of DNA repair.
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Affiliation(s)
- G de Piédoue
- INSERM U733, Laboratoire de Thérapie Génique Hématopoïétique, Institut Universitaire d'Hématologie, Hôpital Saint-Louis, 75010 Paris, France
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32
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Andrieu-Soler C, Halhal M, Boatright JH, Padove SA, Nickerson JM, Stodulkova E, Stewart RE, Ciavatta VT, Doat M, Jeanny JC, de Bizemont T, Sennlaub F, Courtois Y, Behar-Cohen F. Single-stranded oligonucleotide-mediated in vivo gene repair in the rd1 retina. Mol Vis 2007; 13:692-706. [PMID: 17563719 PMCID: PMC2765472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PURPOSE The aim of this study was to test whether oligonucleotide-targeted gene repair can correct the point mutation in genomic DNA of PDE6b(rd1) (rd1) mouse retinas in vivo. METHODS Oligonucleotides (ODNs) of 25 nucleotide length and complementary to genomic sequence subsuming the rd1 point mutation in the gene encoding the beta-subunit of rod photoreceptor cGMP-phosphodiesterase (beta-PDE), were synthesized with a wild type nucleotide base at the rd1 point mutation position. Control ODNs contained the same nucleotide bases as the wild type ODNs but with varying degrees of sequence mismatch. We previously developed a repeatable and relatively non-invasive technique to enhance ODN delivery to photoreceptor nuclei using transpalpebral iontophoresis prior to intravitreal ODN injection. Three such treatments were performed on C3H/henJ (rd1) mouse pups before postnatal day (PN) 9. Treatment outcomes were evaluated at PN28 or PN33, when retinal degeneration was nearly complete in the untreated rd1 mice. The effect of treatment on photoreceptor survival was evaluated by counting the number of nuclei of photoreceptor cells and by assessing rhodopsin immunohistochemistry on flat-mount retinas and sections. Gene repair in the retina was quantified by allele-specific real time PCR and by detection of beta-PDE-immunoreactive photoreceptors. Confirmatory experiments were conducted using independent rd1 colonies in separate laboratories. These experiments had an additional negative control ODN that contained the rd1 mutant nucleotide base at the rd1 point mutation site such that the sole difference between treatment with wild type and control ODN was the single base at the rd1 point mutation site. RESULTS Iontophoresis enhanced the penetration of intravitreally injected ODNs in all retinal layers. Using this delivery technique, significant survival of photoreceptors was observed in retinas from eyes treated with wild type ODNs but not control ODNs as demonstrated by cell counting and rhodopsin immunoreactivity at PN28. Beta-PDE immunoreactivity was present in retinas from eyes treated with wild type ODN but not from those treated with control ODNs. Gene correction demonstrated by allele-specific real time PCR and by counts of beta-PDE-immunoreactive cells was estimated at 0.2%. Independent confirmatory experiments showed that retinas from eyes treated with wild type ODN contained many more rhodopsin immunoreactive cells compared to retinas treated with control (rd1 sequence) ODN, even when harvested at PN33. CONCLUSIONS Short ODNs can be delivered with repeatable efficiency to mouse photoreceptor cells in vivo using a combination of intravitreal injection and iontophoresis. Delivery of therapeutic ODNs to rd1 mouse eyes resulted in genomic DNA conversion from mutant to wild type sequence, low but observable beta-PDE immunoreactivity, and preservation of rhodopsin immunopositive cells in the outer nuclear layer, suggesting that ODN-directed gene repair occurred and preserved rod photoreceptor cells. Effects were not seen in eyes treated with buffer or with ODNs having the rd1 mutant sequence, a definitive control for this therapeutic approach. Importantly, critical experiments were confirmed in two laboratories by several different researchers using independent mouse colonies and ODN preparations from separate sources. These findings suggest that targeted gene repair can be achieved in the retina following enhanced ODN delivery.
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Affiliation(s)
- Charlotte Andrieu-Soler
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
- Optis France, Paris, 75015, France
| | - Mounia Halhal
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
| | | | | | | | - Eva Stodulkova
- Emory University, Department of Ophthalmology, Atlanta, GA
| | | | | | - Marc Doat
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
| | - Jean-Claude Jeanny
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
| | - Therèse de Bizemont
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
| | - Florian Sennlaub
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
| | - Yves Courtois
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
| | - Francine Behar-Cohen
- Centre de Recherche des Cordeliers, INSERM, U872, Paris, F-75006 France
- Université Paris Descartes, UMR S 872, Paris, F-75006 France
- Université Pierre et Marie Curie- Paris 6, UMR S 872, Paris, F-75006 France
- Rothschild Ophthalmologic Foundation, Paris, France
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Aarts M, Dekker M, de Vries S, van der Wal A, te Riele H. Generation of a mouse mutant by oligonucleotide-mediated gene modification in ES cells. Nucleic Acids Res 2006; 34:e147. [PMID: 17142234 PMCID: PMC1669774 DOI: 10.1093/nar/gkl896] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Oligonucleotide-mediated gene targeting is emerging as a powerful tool for the introduction of subtle gene modifications in mouse embryonic stem (ES) cells and the generation of mutant mice. However, its efficacy is strongly suppressed by DNA mismatch repair (MMR). Here we report a simple and rapid procedure for the generation of mouse mutants using transient down regulation of the central MMR protein MSH2 by RNA interference. We demonstrate that under this condition, unmodified single-stranded DNA oligonucleotides can be used to substitute single or several nucleotides. In particular, simultaneous substitution of four adjacent nucleotides was highly efficient, providing the opportunity to substitute virtually any given codon. We have used this method to create a codon substitution (N750F) in the Rb gene of mouse ES cells and show that the oligonucleotide-modified Rb allele can be transmitted through the germ line of mice.
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Affiliation(s)
| | | | | | | | - Hein te Riele
- To whom correspondence should be addressed. Tel: +31 20 512 20 84; Fax: +31 20 669 13 83;
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34
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Bloquel C, Bourges JL, Touchard E, Berdugo M, BenEzra D, Behar-Cohen F. Non-viral ocular gene therapy: potential ocular therapeutic avenues. Adv Drug Deliv Rev 2006; 58:1224-42. [PMID: 17095114 DOI: 10.1016/j.addr.2006.07.023] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Accepted: 07/31/2006] [Indexed: 11/16/2022]
Abstract
Non-viral vectors for potential gene replacement and therapy have been developed in order to overcome the drawbacks of viral vectors. The diversity of non-viral vectors allows for a wide range of various products, flexibility of application, ease of use, low-cost of production and enhanced "genomic" safety. Using non-viral strategies, oligonucleotides (ODNs) can be delivered naked (less efficient) or entrapped in cationic lipids, polymers or peptides forming slow release delivery systems, which can be adapted according to the organ targeted and the therapy purposes. Tissue and cell internalization can be further enhanced by changing by physical or chemical means. Moreover, a specific vector can be selected according to disease course and intensity of manifestations fulfilling specific requirements such as the duration of drug release and its level along with cells and tissues specific targeting. From accumulating knowledge and experience, it appears that combination of several non-viral techniques may increase the efficacy and ensure the safety of these evolving and interesting gene therapy strategies.
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Affiliation(s)
- C Bloquel
- INSERM U598, Physiopathology of Ocular Diseases, Therapeutic innovations, René Descartes University, Paris 5, 15 Rue de l'Ecole de Médecine 75006 Paris, France
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