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Katkevics M, MacKay JA, Rozners E. Triplex-forming peptide nucleic acids as emerging ligands to modulate structure and function of complex RNAs. Chem Commun (Camb) 2024; 60:1999-2008. [PMID: 38259187 PMCID: PMC10922694 DOI: 10.1039/d3cc05409h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Over the last three decades, our view of RNA has changed from a simple intermediate supporting protein synthesis to a major regulator of biological processes. In the expanding area of RNA research, peptide nucleic acid (PNA) is emerging as a promising ligand for triple-helical recognition of complex RNAs. As discussed in this feature article, the key advantages of PNAs are high sequence specificity and affinity for RNA (>10 fold higher than for DNA) that are difficult to achieve with small molecule ligands. Emerging studies demonstrate that triple-helical binding of PNAs can modulate biological function and control dynamic conformational equilibria of complex folded RNAs. These results suggest that PNA has a unique potential as a research tool and therapeutic compound targeting RNA. The remaining problems hampering advances in these directions are limitations of sequences that can be recognized by Hoogsteen triplexes (typically purine rich tracts), poor cellular uptake and bioavailability of PNA, and potential off-target effects in biological systems. Recent exciting studies are discussed that illustrate how synthetic nucleic acid chemistry provides innovative solutions for these problems.
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Affiliation(s)
- Martins Katkevics
- Latvian Institute of Organic Synthesis, Aizkraukles 21, Riga, LV-1006, Latvia
| | - James A MacKay
- Department of Chemistry and Biochemistry, Elizabethtown College, Elizabethtown, PA 17022, USA
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, Binghamton, NY 13902, USA.
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2
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Singh G, Monga V. Peptide Nucleic Acids: Recent Developments in the Synthesis and Backbone Modifications. Bioorg Chem 2023; 141:106860. [PMID: 37748328 DOI: 10.1016/j.bioorg.2023.106860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 09/07/2023] [Accepted: 09/09/2023] [Indexed: 09/27/2023]
Abstract
Nucleic acid represents the ideal drug candidate for protein targets that are hard to target or against which drug development is not easy. Peptide nucleic acids (PNAs) are synthesized by attaching modified peptide backbones generally derived from repetitive N-2-aminoethyl glycine units in place of the regular phosphodiester backbone and represent synthetic impersonator of nucleic acids that offers an exciting research field due to their fascinating spectrum of biotechnological, diagnostic and potential therapeutic applications. The semi-rigid peptide nucleic acid backbone serves as a nearly-perfect template for attaching complimentary base pairs on DNA or RNA in a sequence-dependent manner as described by Watson-Crick models. PNAs and their analogues are endowed with exceptionally high affinity and specificity for receptor sites, essentially due to their polyamide backbone's uncharged and flexible nature. The present review compiled various strategies to modify the polypeptide backbone for improving the target selectivity and stability of the PNAs in the body. The investigated biological activities carried out on PNAs have also been summarized in the present review.
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Affiliation(s)
- Gurpreet Singh
- Department of Pharmaceutical Chemistry, ISF College of Pharmacy, GT Road, Ghal Kalan, Moga 142001, Punjab, India
| | - Vikramdeep Monga
- Department of Pharmaceutical Sciences and Natural Products, Central University of Punjab, VPO-Ghudda, Bathinda 151401, Punjab, India.
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3
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Brodyagin N, Kataoka Y, Kumpina I, McGee DW, Rozners E. Cellular uptake of 2-aminopyridine-modified peptide nucleic acids conjugated with cell-penetrating peptides. Biopolymers 2021; 113:e23484. [PMID: 34914092 DOI: 10.1002/bip.23484] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 11/30/2021] [Accepted: 12/06/2021] [Indexed: 01/31/2023]
Abstract
Cell-penetrating peptides (CPPs) have been extensively used to deliver peptide nucleic acid (PNA) in cells. We have previously found that replacement of cytosine in triplex-forming PNAs with 2-aminopyridine (M) not only enhanced RNA binding, but also improved cellular uptake of PNAs. In this study, we used confocal fluorescence microscopy to evaluate the ability of CPPs to further improve cellular uptake of M-modified PNAs. We found that PNAs conjugated with Tat and octa-arginine peptides were effectively taken up in MCF7 cells when supplied in cell media at 1 μM. Remarkably, M-modified PNA without any CPP conjugation also showed strong uptake when the concentration was increased to 5 μM. Majority of PNA conjugates remained localized in distinct cytoplasmic vesicles, as judged by dot-like fluorescence patterns. However, M-modified PNAs conjugated with Tat, octa-arginine, and even a simple tri-lysine peptide also showed dispersed fluorescence in cytoplasm and were taken up in nuclei where they localized in larger vesicles, most likely nucleoli. Endosomolytic peptides or chemicals (chloroquine and CaCl2 ) did not release the conjugates from cytosolic vesicles, which suggested that the PNAs were not entrapped in endosomes. We hypothesize that M-modified PNAs escape endosomes and accumulate in cellular compartments rich in RNA, such as nucleoli, stress granules, and P-bodies.
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Affiliation(s)
- Nikita Brodyagin
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Yuka Kataoka
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Ilze Kumpina
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Dennis W McGee
- Department of Biological Sciences, Binghamton University, The State University of New York, Binghamton, New York, USA
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York, USA
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4
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Endoh T, Brodyagin N, Hnedzko D, Sugimoto N, Rozners E. Triple-Helical Binding of Peptide Nucleic Acid Inhibits Maturation of Endogenous MicroRNA-197. ACS Chem Biol 2021; 16:1147-1151. [PMID: 34114795 DOI: 10.1021/acschembio.1c00133] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Sequence specific recognition and functional inhibition of biomedically relevant double-helical RNAs is highly desirable but remains a formidable problem. The present study demonstrates that electroporation of a triplex-forming peptide nucleic acid (PNA), modified with 2-aminopyridine (M) nucleobases, inhibited maturation of endogenous microRNA-197 in SH-SY5Y cells, while having little effect on maturation of microRNA-155 or -27a. In vitro RNA binding and Dicer inhibition assays suggested that the observed biological activity was most likely due to a sequence-specific PNA-RNA triplex formation that inhibited the activity of endonucleases responsible for microRNA maturation. The present study is the first example of modulation of activity of endogenous noncoding RNA using M-modified triplex-forming PNA.
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Affiliation(s)
- Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Nikita Brodyagin
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Dziyana Hnedzko
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
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5
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Binzel DW, Li X, Burns N, Khan E, Lee WJ, Chen LC, Ellipilli S, Miles W, Ho YS, Guo P. Thermostability, Tunability, and Tenacity of RNA as Rubbery Anionic Polymeric Materials in Nanotechnology and Nanomedicine-Specific Cancer Targeting with Undetectable Toxicity. Chem Rev 2021; 121:7398-7467. [PMID: 34038115 DOI: 10.1021/acs.chemrev.1c00009] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
RNA nanotechnology is the bottom-up self-assembly of nanometer-scale architectures, resembling LEGOs, composed mainly of RNA. The ideal building material should be (1) versatile and controllable in shape and stoichiometry, (2) spontaneously self-assemble, and (3) thermodynamically, chemically, and enzymatically stable with a long shelf life. RNA building blocks exhibit each of the above. RNA is a polynucleic acid, making it a polymer, and its negative-charge prevents nonspecific binding to negatively charged cell membranes. The thermostability makes it suitable for logic gates, resistive memory, sensor set-ups, and NEM devices. RNA can be designed and manipulated with a level of simplicity of DNA while displaying versatile structure and enzyme activity of proteins. RNA can fold into single-stranded loops or bulges to serve as mounting dovetails for intermolecular or domain interactions without external linking dowels. RNA nanoparticles display rubber- and amoeba-like properties and are stretchable and shrinkable through multiple repeats, leading to enhanced tumor targeting and fast renal excretion to reduce toxicities. It was predicted in 2014 that RNA would be the third milestone in pharmaceutical drug development. The recent approval of several RNA drugs and COVID-19 mRNA vaccines by FDA suggests that this milestone is being realized. Here, we review the unique properties of RNA nanotechnology, summarize its recent advancements, describe its distinct attributes inside or outside the body and discuss potential applications in nanotechnology, medicine, and material science.
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Affiliation(s)
- Daniel W Binzel
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Xin Li
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Nicolas Burns
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Eshan Khan
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, College of Medicine, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wen-Jui Lee
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Li-Ching Chen
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Satheesh Ellipilli
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wayne Miles
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, College of Medicine, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yuan Soon Ho
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Peixuan Guo
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
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6
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Nucleobase-Modified Triplex-Forming Peptide Nucleic Acids for Sequence-Specific Recognition of Double-Stranded RNA. Methods Mol Biol 2021; 2105:157-172. [PMID: 32088869 DOI: 10.1007/978-1-0716-0243-0_9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Because of the important roles noncoding RNAs play in gene expression, their sequence-specific recognition is important for both fundamental science and the pharmaceutical industry. However, most noncoding RNAs fold in complex helical structures that are challenging problems for molecular recognition. Herein, we describe a method for sequence-specific recognition of double-stranded RNA using peptide nucleic acids (PNAs) that form triple helices in the major grove of RNA under physiologically relevant conditions. We also outline methods for solid-phase conjugation of PNA with cell-penetrating peptides and fluorescent dyes. Protocols for PNA preparation and binding studies using isothermal titration calorimetry are described in detail.
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7
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Singh KRB, Sridevi P, Singh RP. Potential applications of peptide nucleic acid in biomedical domain. ENGINEERING REPORTS : OPEN ACCESS 2020; 2:e12238. [PMID: 32838227 PMCID: PMC7404446 DOI: 10.1002/eng2.12238] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 06/19/2020] [Accepted: 06/19/2020] [Indexed: 05/03/2023]
Abstract
Peptide Nucleic Acid (PNA) are DNA/RNA synthetic analogs with 2-([2-aminoethyl] amino) acetic acid backbone. They partake unique antisense and antigene properties, just due to its inhibitory effect on transcription and translation; they also undergo complementary binding to RNA/DNA with high affinity and specificity. Hence, to date, many methods utilizing PNA for diagnosis and treatment of various diseases namely cancer, AIDS, human papillomavirus, and so on, have been designed and developed. They are being used widely in polymerase chain reaction modulation/mutation, fluorescent in-situ hybridization, and in microarray as a probe; they are also utilized in many in-vitro and in-vivo assays and for developing micro and nano-sized biosensor/chip/array technologies. Earlier reviews, focused only on PNA properties, structure, and modifications related to diagnostics and therapeutics; our review emphasizes on PNA properties and synthesis along with its potential applications in diagnosis and therapeutics. Furthermore, prospects in biomedical applications of PNAs are being discussed in depth.
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Affiliation(s)
- Kshitij RB Singh
- Department of Biotechnology, Faculty of ScienceIndira Gandhi National Tribal UniversityAmarkantakMadhya Pradesh484887India
| | - Parikipandla Sridevi
- Department of Biotechnology, Faculty of ScienceIndira Gandhi National Tribal UniversityAmarkantakMadhya Pradesh484887India
| | - Ravindra Pratap Singh
- Department of Biotechnology, Faculty of ScienceIndira Gandhi National Tribal UniversityAmarkantakMadhya Pradesh484887India
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8
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Tähtinen V, Verhassel A, Tuomela J, Virta P. γ-(S)-Guanidinylmethyl-Modified Triplex-Forming Peptide Nucleic Acids Increase Hoogsteen-Face Affinity for a MicroRNA and Enhance Cellular Uptake. Chembiochem 2019; 20:3041-3051. [PMID: 31206960 DOI: 10.1002/cbic.201900393] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Indexed: 12/14/2022]
Abstract
γ-Modified (i.e., (S)-aminomethyl, (S)-acetamidomethyl, (R)-4-(hydroxymethyl)triazol-1-ylmethyl, and (S)-guanidinylmethyl) triplex-forming peptide nucleic acids (TFPNAs) were synthesized and the effect of the backbone modifications on the binding to a miR-215 model was studied. Among the modifications, an appropriate pattern of three γ-(S)-guanidinylmethyl modifications increased the affinity and Hoogsteen-face selectivity for the miR-215 model without ternary (PNA)2 /RNA complex formation. Moreover, the γ-(S)-guanidinylmethyl groups were observed to facilitate internalization of the TFPNAs into living PC-3 prostate cancer cells.
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Affiliation(s)
- Ville Tähtinen
- Department of Chemistry, University of Turku, Vatselankatu 2, 20014, Turku, Finland
| | - Alejandra Verhassel
- FICAN West Cancer Research Laboratory, University of Turku and Turku University Hospital, Institution of Biomedicine, Medisiina D, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Johanna Tuomela
- FICAN West Cancer Research Laboratory, University of Turku and Turku University Hospital, Institution of Biomedicine, Medisiina D, Kiinamyllynkatu 10, 20520, Turku, Finland
| | - Pasi Virta
- Department of Chemistry, University of Turku, Vatselankatu 2, 20014, Turku, Finland
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9
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Abstract
While <2% of DNA encodes for functional proteins, >70% is transcribed into RNA. Although the function of most RNA transcripts is unknown, such non-coding RNAs are attractive targets for molecular recognition because of the potentially important roles they play in regulation of gene expression and development of disease. In this chapter, we describe peptide nucleic acids (PNAs) that form sequence-specific triple helices with double-stranded RNA (dsRNA). We provide protocols for sequence design and biophysical characterization of PNAs and discuss first examples where such PNAs have been used for functional modulation of dsRNA. The triplex-forming PNAs represent a new approach for RNA recognition that may find future applications in fundamental science, biotechnology and medicine.
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10
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Sabale P, Ambi UB, Srivatsan SG. Clickable PNA Probes for Imaging Human Telomeres and Poly(A) RNAs. ACS OMEGA 2018; 3:15343-15352. [PMID: 30556003 PMCID: PMC6289544 DOI: 10.1021/acsomega.8b02550] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 10/31/2018] [Indexed: 05/10/2023]
Abstract
The ability to bind strongly to complementary nucleic acid sequences, invade complex nucleic acid structures, and resist degradation by cellular enzymes has made peptide nucleic acid (PNA) oligomers as very useful hybridization probes in molecular diagnosis. For such applications, the PNA oligomers have to be labeled with appropriate reporters as they lack intrinsic labels that can be used in biophysical assays. Although solid-phase synthesis is commonly used to attach reporters onto PNA, development of milder and modular labeling methods will provide access to PNA oligomers labeled with a wider range of biophysical tags. Here, we describe the establishment of a postsynthetic modification strategy based on bioorthogonal chemical reactions in functionalizing PNA oligomers in solution with a variety of tags. A toolbox composed of alkyne- and azide-modified monomers were site-specifically incorporated into PNA oligomers and postsynthetically click-functionalized with various tags, ranging from sugar, amino acid, biotin, to fluorophores, by using copper(I)-catalyzed azide-alkyne cycloaddition, strain-promoted azide-alkyne cycloaddition, and Staudinger ligation reactions. As a proof of utility of this method, fluorescent PNA hybridization probes were developed and used in imaging human telomeres in chromosomes and poly(A) RNAs in cells. Taken together, this simple approach of generating a wide range of functional PNA oligomers will expand the use of PNA in molecular diagnosis.
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Endoh T, Annoni C, Hnedzko D, Rozners E, Sugimoto N. Triplex-forming PNA modified with unnatural nucleobases: the role of protonation entropy in RNA binding. Phys Chem Chem Phys 2018; 18:32002-32006. [PMID: 27869270 DOI: 10.1039/c6cp05013a] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Peptide nucleic acid (PNA) modified with unnatural nucleobases enables the formation of a highly stable triplex with a double-stranded RNA at physiological pH. In this communication, we evaluated kinetics and thermodynamics of PNA/RNA triplex formation as a function of both pH and temperature. Protonation entropy was found to be the major factor responsible for the destabilization of the triplex and for the progressive decrease in the association rate at more basic pHs.
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Affiliation(s)
- Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan.
| | - Chiara Annoni
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan.
| | - Dziyana Hnedzko
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902, USA
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902, USA
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan. and Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
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12
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Hnedzko D, McGee DW, Karamitas YA, Rozners E. Sequence-selective recognition of double-stranded RNA and enhanced cellular uptake of cationic nucleobase and backbone-modified peptide nucleic acids. RNA (NEW YORK, N.Y.) 2017; 23:58-69. [PMID: 27742909 PMCID: PMC5159649 DOI: 10.1261/rna.058362.116] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 10/08/2016] [Indexed: 05/07/2023]
Abstract
Sequence-selective recognition of complex RNAs in live cells could find broad applications in biology, biomedical research, and biotechnology. However, specific recognition of structured RNA is challenging, and generally applicable and effective methods are lacking. Recently, we found that peptide nucleic acids (PNAs) were unusually well-suited ligands for recognition of double-stranded RNAs. Herein, we report that 2-aminopyridine (M) modified PNAs and their conjugates with lysine and arginine tripeptides form strong (Ka = 9.4 to 17 × 107 M-1) and sequence-selective triple helices with RNA hairpins at physiological pH and salt concentration. The affinity of PNA-peptide conjugates for the matched RNA hairpins was unusually high compared to the much lower affinity for DNA hairpins of the same sequence (Ka = 0.05 to 1.1 × 107 M-1). The binding of double-stranded RNA by M-modified PNA-peptide conjugates was a relatively fast process (kon = 2.9 × 104 M-1 sec-1) compared to the notoriously slow triple helix formation by oligodeoxynucleotides (kon ∼ 103 M-1 sec-1). M-modified PNA-peptide conjugates were not cytotoxic and were efficiently delivered in the cytosol of HEK293 cells at 10 µM. Surprisingly, M-modified PNAs without peptide conjugation were also taken up by HEK293 cells, which, to the best of our knowledge, is the first example of heterocyclic base modification that enhances the cellular uptake of PNA. Our results suggest that M-modified PNA-peptide conjugates are promising probes for sequence-selective recognition of double-stranded RNA in live cells and other biological systems.
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Affiliation(s)
- Dziyana Hnedzko
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902, USA
| | - Dennis W McGee
- Department of Biological Sciences, Binghamton University, State University of New York, Binghamton, New York 13902, USA
| | - Yannis A Karamitas
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902, USA
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902, USA
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13
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Xia X, Yu H, Wang L, ul-Abdin Z. Recent progress in ferrocene- and azobenzene-based photoelectric responsive materials. RSC Adv 2016. [DOI: 10.1039/c6ra16201k] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Ferrocene- and azobenzene-based derivatives are commonly used photoelectric responsive materials and possess wide range of applications.
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Affiliation(s)
- Xia Xia
- State Key Laboratory of Chemical Engineering
- College of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Haojie Yu
- State Key Laboratory of Chemical Engineering
- College of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Li Wang
- State Key Laboratory of Chemical Engineering
- College of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Zain ul-Abdin
- State Key Laboratory of Chemical Engineering
- College of Chemical and Biological Engineering
- Zhejiang University
- Hangzhou 310027
- China
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