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Domínguez A, Gargallo R, Cuestas-Ayllón C, Grazu V, Fàbrega C, Valiuska S, Noé V, Ciudad CJ, Calderon EJ, de la Fuente JM, Eritja R, Aviñó A. Biophysical evaluation of antiparallel triplexes for biosensing and biomedical applications. Int J Biol Macromol 2024; 264:130540. [PMID: 38430998 DOI: 10.1016/j.ijbiomac.2024.130540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/07/2024] [Accepted: 02/27/2024] [Indexed: 03/05/2024]
Abstract
Polypyrimidine sequences can be targeted by antiparallel clamps forming triplex structures either for biosensing or therapeutic purposes. Despite its successful implementation, their biophysical properties remain to be elusive. In this work, PAGE, circular dichroism and multivariate analysis were used to evaluate the properties of PPRHs directed to SARS-CoV-2 genome. Several PPRHs designed to target various polypyrimidine sites within the viral genome were synthesized. These PPRHs displayed varying binding affinities, influenced by factors such as the length of the PPRH and its GC content. The number and position of pyrimidine interruptions relative to the 4 T loop of the PPRH was found a critical factor, affecting the binding affinity with the corresponding target. Moreover, these factors also showed to affect in the intramolecular and intermolecular equilibria of PPRHs alone and when hybridized to their corresponding targets, highlighting the polymorphic nature of these systems. Finally, the functionality of the PPRHs was evaluated in a thermal lateral flow sensing device showing a good correspondence between their biophysical properties and detection limits. These comprehensive studies contribute to the understanding of the critical factors involved in the design of PPRHs for effective targeting of biologically relevant genomes through the formation of triplex structures under neutral conditions.
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Affiliation(s)
- Arnau Domínguez
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain; Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | - Raimundo Gargallo
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona (UB), 08028 Barcelona, Spain
| | - Carlos Cuestas-Ayllón
- Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain; Instituto de Nanociencia y Materiales de Aragón (INMA), Consejo Superior de Investigaciones Científicas (CSIC), 50018 Zaragoza, Spain
| | - Valeria Grazu
- Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain; Instituto de Nanociencia y Materiales de Aragón (INMA), Consejo Superior de Investigaciones Científicas (CSIC), 50018 Zaragoza, Spain
| | - Carme Fàbrega
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain; Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
| | - Simonas Valiuska
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences and Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona (UB), 08028 Barcelona, Spain
| | - Véronique Noé
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences and Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona (UB), 08028 Barcelona, Spain
| | - Carlos J Ciudad
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences and Institute of Nanoscience and Nanotechnology (IN2UB), University of Barcelona (UB), 08028 Barcelona, Spain
| | - Enrique J Calderon
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla, Sevilla, Spain; Centro de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), 28029 Madrid, Spain
| | - Jesús Martínez de la Fuente
- Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain; Instituto de Nanociencia y Materiales de Aragón (INMA), Consejo Superior de Investigaciones Científicas (CSIC), 50018 Zaragoza, Spain
| | - Ramon Eritja
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain; Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain.
| | - Anna Aviñó
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain; Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain.
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Valiuska S, Psaras AM, Noé V, Brooks TA, Ciudad CJ. Targeting MYC Regulation with Polypurine Reverse Hoogsteen Oligonucleotides. Int J Mol Sci 2022; 24:ijms24010378. [PMID: 36613820 PMCID: PMC9820101 DOI: 10.3390/ijms24010378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/07/2022] [Accepted: 12/20/2022] [Indexed: 12/29/2022] Open
Abstract
The oncogene MYC has key roles in transcription, proliferation, deregulating cellular energetics, and more. Modulating the expression or function of the MYC protein is a viable therapeutic goal in an array of cancer types, and potential inhibitors of MYC with high specificity and selectivity are of great interest. In cancer cells addicted to their aberrant MYC function, suppression can lead to apoptosis, with minimal effects on non-addicted, non-oncogenic cells, providing a wide therapeutic window for specific and efficacious anti-tumor treatment. Within the promoter of MYC lies a GC-rich, G-quadruplex (G4)-forming region, wherein G4 formation is capable of mediating transcriptional downregulation of MYC. Such GC-rich regions of DNA are prime targets for regulation with Polypurine Reverse Hoogsteen hairpins (PPRHs). The current study designed and examined PPRHs targeting the G4-forming and four other GC-rich regions of DNA within the promoter or intronic regions. Six total PPRHs were designed, examined in cell-free conditions for target engagement and in cells for transcriptional modulation, and correlating cytotoxic activity in pancreatic, prostate, neuroblastoma, colorectal, ovarian, and breast cancer cells. Two lead PPRHs, one targeting the promoter G4 and one targeting Intron 1, were identified with high potential for further development as an innovative approach to both G4 stabilization and MYC modulation.
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Affiliation(s)
- Simonas Valiuska
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Alexandra Maria Psaras
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY 13902, USA
| | - Véronique Noé
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Tracy A. Brooks
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY 13902, USA
- Correspondence: (C.J.C.); (T.A.B.); Tel.: +34-93-403-4455 (C.J.C.)
| | - Carlos J. Ciudad
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
- Correspondence: (C.J.C.); (T.A.B.); Tel.: +34-93-403-4455 (C.J.C.)
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Psaras AM, Valiuska S, Noé V, Ciudad CJ, Brooks TA. Targeting KRAS Regulation with PolyPurine Reverse Hoogsteen Oligonucleotides. Int J Mol Sci 2022; 23:2097. [PMID: 35216221 DOI: 10.3390/ijms23042097] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/02/2022] [Accepted: 02/09/2022] [Indexed: 02/04/2023] Open
Abstract
KRAS is a GTPase involved in the proliferation signaling of several growth factors. The KRAS gene is GC-rich, containing regions with known and putative G-quadruplex (G4) forming regions. Within the middle of the G-rich proximal promoter, stabilization of the physiologically active G4mid structure downregulates transcription of KRAS; the function and formation of other G4s within the gene are unknown. Herein we identify three putative G4-forming sequences (G4FS) within the KRAS gene, explore their G4 formation, and develop oligonucleotides targeting these three regions and the G4mid forming sequence. We tested Polypurine Reverse Hoogsteen hairpins (PPRHs) for their effects on KRAS regulation via enhancing G4 formation or displacing G-rich DNA strands, downregulating KRAS transcription and mediating an anti-proliferative effect. Five PPRH were designed, two against the KRAS promoter G4mid and three others against putative G4FS in the distal promoter, intron 1 and exon 5. PPRH binding was confirmed by gel electrophoresis. The effect on KRAS transcription was examined by luciferase, FRET Melt2, qRT-PCR. Cytotoxicity was evaluated in pancreatic and ovarian cancer cells. PPRHs decreased activity of a luciferase construct driven by the KRAS promoter. PPRH selectively suppressed proliferation in KRAS dependent cancer cells. PPRH demonstrated synergistic activity with a KRAS promoter selective G4-stabilizing compound, NSC 317605, in KRAS-dependent pancreatic cells. PPRHs selectively stabilize G4 formation within the KRAS mid promoter region and represent an innovative approach to both G4-stabilization and to KRAS modulation with potential for development into novel therapeutics.
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Aubets E, Chillon M, Ciudad CJ, Noé V. PolyPurine Reverse Hoogsteen Hairpins Work as RNA Species for Gene Silencing. Int J Mol Sci 2021; 22:10025. [PMID: 34576188 PMCID: PMC8466063 DOI: 10.3390/ijms221810025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 09/13/2021] [Accepted: 09/14/2021] [Indexed: 12/21/2022] Open
Abstract
PolyPurine Reverse Hoogsteen Hairpins (PPRHs) are gene-silencing DNA-oligonucleotides developed in our laboratory that are formed by two antiparallel polypurine mirror repeat domains bound intramolecularly by Hoogsteen bonds. The aim of this work was to explore the feasibility of using viral vectors to deliver PPRHs as a gene therapy tool. After treatment with synthetic RNA, plasmid transfection, or viral infection targeting the survivin gene, viability was determined by the MTT assay, mRNA was determined by RT-qPCR, and protein levels were determined by Western blot. We showed that the RNA-PPRH induced a decrease in cell viability in a dose-dependent manner and an increase in apoptosis in PC-3 and HeLa cells. Both synthetic RNA-PPRH and RNA-PPRH intracellularly generated upon the transfection of a plasmid vector were able to reduce survivin mRNA and protein levels in PC-3 cells. An adenovirus type-5 vector encoding the PPRH against survivin was also able to decrease survivin mRNA and protein levels, leading to a reduction in HeLa cell viability. In this work, we demonstrated that PPRHs can also work as RNA species, either chemically synthesized, transcribed from a plasmid construct, or transcribed from viral vectors. Therefore, all these results are the proof of principle that viral vectors could be considered as a delivery system for PPRHs.
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Affiliation(s)
- Eva Aubets
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Nanoscience and Nanotechnology Institute, IN2UB, University of Barcelona, 08028 Barcelona, Spain; (E.A.); (C.J.C.)
| | - Miguel Chillon
- ICREA, Institute of Neurosciences at UAB, 08193 Bellaterra, Spain;
- Vall d’Hebron Institute of Research (VHIR), 08035 Barcelona, Spain
| | - Carlos J. Ciudad
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Nanoscience and Nanotechnology Institute, IN2UB, University of Barcelona, 08028 Barcelona, Spain; (E.A.); (C.J.C.)
| | - Véronique Noé
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Nanoscience and Nanotechnology Institute, IN2UB, University of Barcelona, 08028 Barcelona, Spain; (E.A.); (C.J.C.)
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Aubets E, Griera R, Felix AJ, Rigol G, Sikorski C, Limón D, Mastrorosa C, Busquets MA, Pérez-García L, Noé V, Ciudad CJ. Synthesis and validation of DOPY: A new gemini dioleylbispyridinium based amphiphile for nucleic acid transfection. Eur J Pharm Biopharm 2021; 165:279-92. [PMID: 34033881 DOI: 10.1016/j.ejpb.2021.05.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/15/2021] [Accepted: 05/18/2021] [Indexed: 12/19/2022]
Abstract
Nucleic acids therapeutics provide a selective and promising alternative to traditional treatments for multiple genetic diseases. A major obstacle is the development of safe and efficient delivery systems. Here, we report the synthesis of the new cationic gemini amphiphile 1,3-bis[(4-oleyl-1-pyridinio)methyl]benzene dibromide (DOPY). Its transfection efficiency was evaluated using PolyPurine Reverse Hoogsteen hairpins (PPRHs), a nucleic acid tool for gene silencing and gene repair developed in our laboratory. The interaction of DOPY with PPRHs was confirmed by gel retardation assays, and it forms complexes of 155 nm. We also demonstrated the prominent internalization of PPRHs using DOPY compared to other chemical vehicles in SH-SY5Y, PC-3 and DF42 cells. Regarding gene silencing, a specific PPRH against the survivin gene delivered with DOPY decreased survivin protein levels and cell viability more effectively than with N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium methylsulfate (DOTAP) in both SH-SY5Y and PC-3 cells. We also validated the applicability of DOPY in gene repair approaches by correcting a point mutation in the endogenous locus of the dhfr gene in DF42 cells using repair-PPRHs. All these results indicate both an efficient entry and release of PPRHs at the intracellular level. Therefore, DOPY can be considered as a new lipid-based vehicle for the delivery of therapeutic oligonucleotides.
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Noé V, Aubets E, Félix AJ, Ciudad CJ. Nucleic acids therapeutics using PolyPurine Reverse Hoogsteen hairpins. Biochem Pharmacol 2020; 189:114371. [PMID: 33338475 DOI: 10.1016/j.bcp.2020.114371] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 02/08/2023]
Abstract
PolyPurine Reverse Hoogsteen hairpins (PPRHs) are DNA hairpins formed by intramolecular reverse Hoogsteen bonds which can bind to polypyrimidine stretches in dsDNA by Watson:Crick bonds, thus forming a triplex and displacing the fourth strand of the DNA complex. PPRHs were first described as a gene silencing tool in vitro for DHFR, telomerase and survivin genes. Then, the effect of PPRHs directed against the survivin gene was also determined in vivo using a xenograft model of prostate cancer cells (PC3). Since then, the ability of PPRHs to inhibit gene expression has been explored in other genes involved in cancer (BCL-2, mTOR, topoisomerase, C-MYC and MDM2), in immunotherapy (SIRPα/CD47 and PD-1/PD-L1 tandem) or in replication stress (WEE1 and CHK1). Furthermore, PPRHs have the ability to target the complementary strand of a G-quadruplex motif as a regulatory element of the TYMS gene. PPRHs have also the potential to correct point mutations in the DNA as shown in two collections of CHO cell lines bearing mutations in either the dhfr or aprt loci. Finally, based on the capability of PPRHs to form triplexes, they have been incorporated as probes in biosensors for the determination of the DNA methylation status of PAX-5 in cancer and the detection of mtLSU rRNA for the diagnosis of Pneumocystis jirovecii. Of note, PPRHs have high stability and do not present immunogenicity, hepatotoxicity or nephrotoxicity in vitro. Overall, PPRHs constitute a new economical biotechnological tool with multiple biomedical applications.
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Affiliation(s)
- Véronique Noé
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, & IN2UB, University of Barcelona, 08028 Barcelona, Spain
| | - Eva Aubets
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, & IN2UB, University of Barcelona, 08028 Barcelona, Spain
| | - Alex J Félix
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, & IN2UB, University of Barcelona, 08028 Barcelona, Spain
| | - Carlos J Ciudad
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, & IN2UB, University of Barcelona, 08028 Barcelona, Spain.
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Félix AJ, Solé A, Noé V, Ciudad CJ. Gene Correction of Point Mutations Using PolyPurine Reverse Hoogsteen Hairpins Technology. Front Genome Ed 2020; 2:583577. [PMID: 34713221 PMCID: PMC8525393 DOI: 10.3389/fgeed.2020.583577] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/08/2020] [Indexed: 01/01/2023] Open
Abstract
Monogenic disorders are often the result of single point mutations in specific genes, leading to the production of non-functional proteins. Different blood disorders such as ß-thalassemia, sickle cell disease, hereditary spherocytosis, Fanconi anemia, and Hemophilia A and B are usually caused by point mutations. Gene editing tools including TALENs, ZFNs, or CRISPR/Cas platforms have been developed to correct mutations responsible for different diseases. However, alternative molecular tools such as triplex-forming oligonucleotides and their derivatives (e.g., peptide nucleic acids), not relying on nuclease activity, have also demonstrated their ability to correct mutations in the DNA. Here, we review the Repair-PolyPurine Reverse Hoogsteen hairpins (PPRHs) technology, which can represent an alternative gene editing tool within this field. Repair-PPRHs are non-modified single-stranded DNA molecules formed by two polypurine mirror repeat sequences linked by a five-thymidine bridge, followed by an extended sequence at one end of the molecule which is homologous to the DNA sequence to be repaired but containing the corrected nucleotide. The two polypurine arms of the PPRH are bound by intramolecular reverse-Hoogsteen bonds between the purines, thus forming a hairpin structure. This hairpin core binds to polypyrimidine tracts located relatively near the target mutation in the dsDNA in a sequence-specific manner by Watson-Crick bonds, thus producing a triplex structure which stimulates recombination. This technology has been successfully employed to repair a collection of mutants of the dhfr and aprt genes within their endogenous loci in mammalian cells and could be suitable for the correction of mutations responsible for blood disorders.
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Aubets E, J Félix A, Garavís M, Reyes L, Aviñó A, Eritja R, Ciudad CJ, Noé V. Detection of a G-Quadruplex as a Regulatory Element in Thymidylate synthase for Gene Silencing Using Polypurine Reverse Hoogsteen Hairpins. Int J Mol Sci 2020; 21:E5028. [PMID: 32708710 DOI: 10.3390/ijms21145028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/14/2020] [Accepted: 07/15/2020] [Indexed: 02/08/2023] Open
Abstract
Thymidylate synthase (TYMS) enzyme is an anti-cancer target given its role in DNA biosynthesis. TYMS inhibitors (e.g., 5-Fluorouracil) can lead to drug resistance through an autoregulatory mechanism of TYMS that causes its overexpression. Since G-quadruplexes (G4) can modulate gene expression, we searched for putative G4 forming sequences (G4FS) in the TYMS gene that could be targeted using polypurine reverse Hoogsteen hairpins (PPRH). G4 structures in the TYMS gene were detected using the quadruplex forming G-rich sequences mapper and confirmed through spectroscopic approaches such as circular dichroism and NMR using synthetic oligonucleotides. Interactions between G4FS and TYMS protein or G4FS and a PPRH targeting this sequence (HpTYMS-G4-T) were studied by EMSA and thioflavin T staining. We identified a G4FS in the 5’UTR of the TYMS gene in both DNA and RNA capable of interacting with TYMS protein. The PPRH binds to its corresponding target dsDNA, promoting G4 formation. In cancer cells, HpTYMG-G4-T decreased TYMS mRNA and protein levels, leading to cell death, and showed a synergic effect when combined with 5-fluorouracil. These results reveal the presence of a G4 motif in the TYMS gene, probably involved in the autoregulation of TYMS expression, and the therapeutic potential of a PPRH targeted to the G4FS.
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Félix AJ, Ciudad CJ, Noé V. Correction of the aprt Gene Using Repair-Polypurine Reverse Hoogsteen Hairpins in Mammalian Cells. Mol Ther Nucleic Acids 2019; 19:683-695. [PMID: 31945727 PMCID: PMC6965513 DOI: 10.1016/j.omtn.2019.12.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 12/16/2019] [Accepted: 12/16/2019] [Indexed: 01/01/2023]
Abstract
In this study, we describe the correction of single-point mutations in mammalian cells by repair-polypurine reverse Hoogsteen hairpins (repair-PPRHs). These molecules consist of (1) a PPRH hairpin core that binds to a polypyrimidine target sequence in the double-stranded DNA (dsDNA), producing a triplex structure, and (2) an extension sequence homologous to the DNA sequence to be repaired but containing the wild-type nucleotide instead of the mutation and acting as a donor DNA to correct the mutation. We repaired different point mutations in the adenosyl phosphoribosyl transferase (aprt) gene contained in different aprt-deficient Chinese hamster ovary (CHO) cell lines. Because we had previously corrected mutations in the dihydrofolate reductase (dhfr) gene, in this study, we demonstrate the generality of action of the repair-PPRHs. Repaired cells were analyzed by DNA sequencing, mRNA expression, and enzymatic activity to confirm the correction of the mutation. Moreover, whole-genome sequencing analyses did not detect any off-target effect in the repaired genome. We also performed gel-shift assays to show the binding of the repair-PPRH to the target sequence and the formation of a displacement-loop (D-loop) structure that can trigger a homologous recombination event. Overall, we demonstrate that repair-PPRHs achieve the permanent correction of point mutations in the dsDNA at the endogenous level in mammalian cells without off-target activity.
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Affiliation(s)
- Alex J Félix
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute for Nanoscience and Nanotechnology IN2UB, University of Barcelona, 08028 Barcelona, Spain
| | - Carlos J Ciudad
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute for Nanoscience and Nanotechnology IN2UB, University of Barcelona, 08028 Barcelona, Spain.
| | - Véronique Noé
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; Institute for Nanoscience and Nanotechnology IN2UB, University of Barcelona, 08028 Barcelona, Spain
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