1
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He Z, Wang Z, Lu L, Wang X, Guo G. Enhanced recognition of G-quadruplex DNA oxidative damage based on DNA-mediated charge transfer. Bioelectrochemistry 2024; 158:108714. [PMID: 38653106 DOI: 10.1016/j.bioelechem.2024.108714] [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: 02/13/2024] [Revised: 04/15/2024] [Accepted: 04/20/2024] [Indexed: 04/25/2024]
Abstract
G-quadruplex (G4) DNA is present in human telomere oligonucleotide sequences. Oxidative damage to telomeric DNA accelerates telomere shortening, which is strongly associated with aging and cancer. Most of the current analyses on oxidative DNA damage are based on ds-DNA. Here, we developed a electrochemiluminescence (ECL) probe for enhanced recognition of oxidative damage in G4-DNA based on DNA-mediated charge transfer (CT), which could specifically recognize damaged sites depending on the position of 8-oxoguanine (8-oxoG). First, a uniform G4-DNA monolayer interface was fabricated; the G4-DNA mediated CT properties were examined using an iridium(III) complex [Ir(ppy)2(pip)]PF6 stacked with G4-DNA as an indicator. The results showed that G4-DNA with 8-oxoG attenuated DNA CT. The topological effects of oxidative damage at different sites of G4-DNA and their effects on DNA CT were revealed. The sensing platform was also used for the sensitive and quantitative detection of 8-oxoG in G4-DNA, with a detection limit of 28.9 fmol. Overall, these findings present a sensitive platform to study G4-DNA structural and stability changes caused by oxidative damage as well as the specific and quantitative detection of oxidation sites. The different damage sites in the G-quadruplex could provide detailed clues for understanding the function of G4-associated telomere functional enzymes.
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Affiliation(s)
- Zhangjin He
- Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, Beijing University of Technology, Beijing 100124, PR China
| | - Ziqi Wang
- Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, Beijing University of Technology, Beijing 100124, PR China
| | - Liping Lu
- Key Laboratory of Beijing on Regional Air Pollution Control, Department of Environmental Science, Beijing University of Technology, Beijing 100124, PR China; Center of Excellence for Environmental Safety and Biological Effects, Beijing University of Technology, Beijing 100124, PR China.
| | - Xiayan Wang
- Center of Excellence for Environmental Safety and Biological Effects, Beijing University of Technology, Beijing 100124, PR China
| | - Guangsheng Guo
- Center of Excellence for Environmental Safety and Biological Effects, Beijing University of Technology, Beijing 100124, PR China
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2
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Lacen AN, Symasek A, Gunter A, Lee HT. Slow G-Quadruplex Conformation Rearrangement and Accessibility Change Induced by Potassium in Human Telomeric Single-Stranded DNA. J Phys Chem B 2024. [PMID: 38875355 DOI: 10.1021/acs.jpcb.4c00719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2024]
Abstract
The guanine-rich telomeric repeats can form G-quadruplexes (G4s) that alter the accessibility of the single-stranded telomeric overhang. In this study, we investigated the effects of Na+ and K+ on G4 folding and accessibility through cation introduction and exchange. We combined differential scanning calorimetry (DSC), circular dichroism (CD), and single molecule Förster resonance energy transfer (smFRET) to monitor the stability, conformational dynamics, and complementary strand binding accessibility of G4 formed by single-stranded telomeric DNA. Our data showed that G4 formed through heating and slow cooling in K+ solution exhibited fewer conformational dynamics than G4 formed in Na+ solution, which is consistent with the higher thermal stability of G4 in K+. Monitoring cation exchange with real time smFRET at room temperature shows that Na+ and K+ can replace each other in G4. When encountering high K+ at room or body temperature, G4 undergoes a slow conformational rearrangement process which is mostly complete by 2 h. The slow conformational rearrangement ends with a stable G4 that is unable to be unfolded by a complementary strand. This study provides new insights into the accessibility of G4 forming sequences at different time points after introduction to a high K+ environment in cells, which may affect how the nascent telomeric overhang interacts with proteins and telomerase.
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Affiliation(s)
- Arianna N Lacen
- Department of Chemistry, University of Alabama at Birmingham, 901 14th Street South, Birmingham, Alabama 35294, United States
| | - Andrew Symasek
- Department of Chemistry, University of Alabama at Birmingham, 901 14th Street South, Birmingham, Alabama 35294, United States
| | - Alan Gunter
- Department of Chemistry, University of Alabama at Birmingham, 901 14th Street South, Birmingham, Alabama 35294, United States
| | - Hui-Ting Lee
- Department of Chemistry, University of Alabama at Birmingham, 901 14th Street South, Birmingham, Alabama 35294, United States
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3
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Vaurs M, Dolu EB, Decottignies A. Mitochondria and telomeres: hand in glove. Biogerontology 2024; 25:289-300. [PMID: 37864609 DOI: 10.1007/s10522-023-10074-7] [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: 09/15/2023] [Accepted: 10/04/2023] [Indexed: 10/23/2023]
Abstract
Born as an endosymbiont, the bacteria engulfed by the proto-eukaryotic cell more than 1.45 billion years ago progressively evolved as an important organelle with multiple interactions with the host cell. In particular, strong connections between mitochondria and the chromosome ends, the telomeres, led to propose a new theory of ageing in which dysfunctional telomeres and mitochondria are the main actors of a vicious circle reducing cell fitness and promoting cellular ageing. We review the evidences that oxidative stress and dysfunctional mitochondria damage telomeres and further discuss the interrelationship between telomere biology and mitochondria through the lens of telomerase which shuttles between the nucleus and mitochondria. Finally, we elaborate on the possible role of the mitochondrial genome on the inheritance of human telomere length through the expression of mitochondrial gene variants.
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Affiliation(s)
- Mélina Vaurs
- de Duve Institute, UCLouvain, Avenue Hippocrate, 1200, Brussels, Belgium.
| | - Elif Beyza Dolu
- de Duve Institute, UCLouvain, Avenue Hippocrate, 1200, Brussels, Belgium
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4
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Johnson S, Paul T, Sanford S, Schnable BL, Detwiler A, Thosar S, Van Houten B, Myong S, Opresko P. BG4 antibody can recognize telomeric G-quadruplexes harboring destabilizing base modifications and lesions. Nucleic Acids Res 2024; 52:1763-1778. [PMID: 38153143 PMCID: PMC10939409 DOI: 10.1093/nar/gkad1209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 11/30/2023] [Accepted: 12/11/2023] [Indexed: 12/29/2023] Open
Abstract
BG4 is a single-chain variable fragment antibody shown to bind various G-quadruplex (GQ) topologies with high affinity and specificity, and to detect GQ in cells, including GQ structures formed within telomeric TTAGGG repeats. Here, we used ELISA and single-molecule pull-down (SiMPull) detection to test how various lengths and GQ destabilizing base modifications in telomeric DNA constructs alter BG4 binding. We observed high-affinity BG4 binding to telomeric GQ independent of telomere length, although three telomeric repeat constructs that cannot form stable intramolecular GQ showed reduced affinity. A single guanine substitution with 8-aza-7-deaza-G, T, A, or C reduced affinity to varying degrees depending on the location and base type, whereas two G substitutions in the telomeric construct dramatically reduced or abolished binding. Substitution with damaged bases 8-oxoguanine and O6-methylguanine failed to prevent BG4 binding although affinity was reduced depending on lesion location. SiMPull combined with FRET revealed that BG4 binding promotes folding of telomeric GQ harboring a G to T substitution or 8-oxoguanine. Atomic force microscopy revealed that BG4 binds telomeric GQ with a 1:1 stoichiometry. Collectively, our data suggest that BG4 can recognize partially folded telomeric GQ structures and promote telomeric GQ stability.
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Affiliation(s)
- Samuel A Johnson
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
- Molecular Biophysics and Structural Biology Graduate Program, University of Pittsburgh, PA 15260, USA
| | - Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Samantha L Sanford
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
| | - Brittani L Schnable
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
- Molecular Biophysics and Structural Biology Graduate Program, University of Pittsburgh, PA 15260, USA
| | - Ariana C Detwiler
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
| | - Sanjana A Thosar
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
| | - Bennett Van Houten
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
- Molecular Biophysics and Structural Biology Graduate Program, University of Pittsburgh, PA 15260, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, PA 15213, USA
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Patricia L Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA 15261, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA
- Molecular Biophysics and Structural Biology Graduate Program, University of Pittsburgh, PA 15260, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, PA 15213, USA
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5
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Kuan XY, Fauzi NSA, Ng KY, Bakhtiar A. Exploring the Causal Relationship Between Telomere Biology and Alzheimer's Disease. Mol Neurobiol 2023; 60:4169-4183. [PMID: 37046137 PMCID: PMC10293431 DOI: 10.1007/s12035-023-03337-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 04/03/2023] [Indexed: 04/14/2023]
Abstract
Telomeres, also known as the "protective caps" of our chromosomes, shorten with each cell cycle due to the end replication problem. This process, termed telomere attrition, is associated with many age-related disorders, such as Alzheimer's disease (AD). Despite the numerous studies conducted in this field, the role of telomere attrition in the onset of the disease remains unclear. To investigate the causal relationship between short telomeres and AD, this review aims to highlight the primary factors that regulate telomere length and maintain its integrity, with an additional outlook on the role of oxidative stress, which is commonly associated with aging and molecular damage. Although some findings thus far might be contradictory, telomere attrition likely plays a crucial role in the progression of AD due to its close association with oxidative stress. The currently available treatments for AD are only symptomatic without affecting the progression of the disease. The components of telomere biology discussed in this paper have previously been studied as an alternative treatment option for several diseases and have exhibited promising in vitro and in vivo results. Hence, this should provide a basis for future research to develop a potential therapeutic strategy for AD. (Created with BioRender.com).
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Affiliation(s)
- Xi-Yuen Kuan
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia
| | - Nurul Syahira Ahmad Fauzi
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia
| | - Khuen Yen Ng
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia
| | - Athirah Bakhtiar
- School of Pharmacy, Monash University Malaysia, Jalan Lagoon Selatan, 47500, Bandar Sunway, Selangor, Malaysia.
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6
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Gorini F, Ambrosio S, Lania L, Majello B, Amente S. The Intertwined Role of 8-oxodG and G4 in Transcription Regulation. Int J Mol Sci 2023; 24:ijms24032031. [PMID: 36768357 PMCID: PMC9916577 DOI: 10.3390/ijms24032031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/11/2023] [Accepted: 01/14/2023] [Indexed: 01/22/2023] Open
Abstract
The guanine base in nucleic acids is, among the other bases, the most susceptible to being converted into 8-Oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) when exposed to reactive oxygen species. In double-helix DNA, 8-oxodG can pair with adenine; hence, it may cause a G > T (C > A) mutation; it is frequently referred to as a form of DNA damage and promptly corrected by DNA repair mechanisms. Moreover, 8-oxodG has recently been redefined as an epigenetic factor that impacts transcriptional regulatory elements and other epigenetic modifications. It has been proposed that 8-oxodG exerts epigenetic control through interplay with the G-quadruplex (G4), a non-canonical DNA structure, in transcription regulatory regions. In this review, we focused on the epigenetic roles of 8-oxodG and the G4 and explored their interplay at the genomic level.
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Affiliation(s)
- Francesca Gorini
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, 80131 Naples, Italy
| | - Susanna Ambrosio
- Department of Biology, University of Naples Federico II, 80138 Naples, Italy
| | - Luigi Lania
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, 80131 Naples, Italy
| | - Barbara Majello
- Department of Biology, University of Naples Federico II, 80138 Naples, Italy
| | - Stefano Amente
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, 80131 Naples, Italy
- Correspondence:
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7
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Moazamian A, Gharagozloo P, Aitken RJ, Drevet JR. OXIDATIVE STRESS AND REPRODUCTIVE FUNCTION: Sperm telomeres, oxidative stress, and infertility. Reproduction 2022; 164:F125-F133. [PMID: 35938805 DOI: 10.1530/rep-22-0189] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/05/2022] [Indexed: 11/08/2022]
Abstract
In brief Oxidative stress is recognized as an underlying driving factor of both telomere dysfunction and human subfertility/infertility. This review briefly reassesses telomere integrity as a fertility biomarker before proposing a novel, mechanistic rationale for the role of oxidative stress in the seemingly paradoxical lengthening of sperm telomeres with aging. Abstract The maintenance of redox balance in the male reproductive tract is critical to sperm health and function. Physiological levels of reactive oxygen species (ROS) promote sperm capacitation, while excess ROS exposure, or depleted antioxidant defenses, yields a state of oxidative stress which disrupts their fertilizing capacity and DNA structural integrity. The guanine moiety is the most readily oxidized of the four DNA bases and gets converted to the mutagenic lesion 8-hydroxy-deoxyguanosine (8-OHdG). Numerous studies have also confirmed oxidative stress as a driving factor behind accelerated telomere shortening and dysfunction. Although a clear consensus has not been reached, clinical studies also appear to associate telomere integrity with fertility outcomes in the assisted reproductive technology setting. Intriguingly, while sperm cellular and molecular characteristics make them more susceptible to oxidative insult than any other cell type, they are also the only cell type in which telomere lengthening accompanies aging. This article focuses on the oxidative stress response pathways to propose a mechanism for the explanation of this apparent paradox.
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Affiliation(s)
- Aron Moazamian
- CellOxess LLC, Ewing, New Jersey, USA.,Université Clermont Auvergne, GReD Institute, CNRS-INSERM, Clermont-Ferrand, France
| | | | - Robert J Aitken
- Priority Research Centre for Reproductive Science, University of Newcastle, Callaghan, New South Wales, Australia
| | - Joël R Drevet
- Université Clermont Auvergne, GReD Institute, CNRS-INSERM, Clermont-Ferrand, France
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8
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Interface of G-quadruplex with both stabilizing and destabilizing ligands for targeting various diseases. Int J Biol Macromol 2022; 219:414-427. [DOI: 10.1016/j.ijbiomac.2022.07.248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/22/2022] [Accepted: 07/29/2022] [Indexed: 11/19/2022]
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9
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Choi BE, Lee HT. DNA-RNA hybrid G-quadruplex tends to form near the 3' end of telomere overhang. Biophys J 2022; 121:2962-2980. [PMID: 35769005 PMCID: PMC9388385 DOI: 10.1016/j.bpj.2022.06.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 01/14/2022] [Accepted: 06/24/2022] [Indexed: 11/25/2022] Open
Abstract
Telomeric repeat-containing RNA (TERRA) has been suggested to participate in telomere maintenance. TERRA consisting of UUAGGG repeats is capable of forming an intermolecular G-quadruplex (GQ) with single-stranded TTAGGG-repeat DNA in the telomere 3' overhang. To explore the structural features and potential functions of this DNA-RNA hybrid GQ (HGQ), we used single-molecule FRET to study the folding patterns of DNA with four to seven telomeric tandem repeats annealed with a short RNA consisting of two or five telomeric repeats. Our data highlight that RNA prefers to form DNA-RNA HGQ near the 3' end of telomeric DNA. Furthermore, the unfolding of secondary structures by a complementary C-rich sequence was observed for DNA GQ but not for DNA-RNA HGQ, which demonstrated the enhanced stability of the telomere 3' end via hybridization with RNA. These conformational and physical properties of telomeric DNA-RNA HGQ suggest that TERRA might limit access to the 3' end of the telomeric DNA overhang, which is known to be critical for the interaction with telomerase and other telomere-associated proteins.
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Affiliation(s)
- Bok-Eum Choi
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama
| | - Hui-Ting Lee
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, Alabama.
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10
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Paul T, Opresko PL, Ha T, Myong S. Vectorial folding of telomere overhang promotes higher accessibility. Nucleic Acids Res 2022; 50:6271-6283. [PMID: 35687089 PMCID: PMC9226509 DOI: 10.1093/nar/gkac401] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 04/20/2022] [Accepted: 06/08/2022] [Indexed: 11/13/2022] Open
Abstract
Human telomere overhang composed of tandem repeats of TTAGGG folds into G-quadruplex (G4). Unlike in an experimental setting in the test tube in which the entire length is allowed to fold at once, inside the cell, the overhang is expected to fold as it is synthesized directionally (5' to 3') and released segmentally by a specialized enzyme, the telomerase. To mimic such vectorial G4 folding process, we employed a superhelicase, Rep-X which can unwind DNA to release the TTAGGG repeats in 5' to 3' direction. We demonstrate that the folded conformation achieved by the refolding of full sequence is significantly different from that of the vectorial folding for two to eight TTAGGG repeats. Strikingly, the vectorially folded state leads to a remarkably higher accessibility to complementary C-rich strand and the telomere binding protein POT1, reflecting a less stably folded state resulting from the vectorial folding. Importantly, our study points to an inherent difference between the co-polymerizing and post-polymerized folding of telomere overhang that can impact telomere architecture and downstream processes.
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Affiliation(s)
- Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, MD21218, USA
| | - Patricia L Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, and UPMC Hillman Cancer Center, Pittsburgh, PA15213, USA
| | - Taekjip Ha
- Department of Biophysics, Johns Hopkins University, Baltimore, MD21218, USA.,Physics Frontier Center (Center for Physics of Living Cells), University of Illinois, 1110 W. Green St., Urbana, IL 61801, USA.,Howard Hughes Medical Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, MD21218, USA.,Physics Frontier Center (Center for Physics of Living Cells), University of Illinois, 1110 W. Green St., Urbana, IL 61801, USA
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11
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Paul T, Myong S. Protocol for generation and regeneration of PEG-passivated slides for single-molecule measurements. STAR Protoc 2022; 3:101152. [PMID: 35146451 PMCID: PMC8819390 DOI: 10.1016/j.xpro.2022.101152] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Single-molecule fluorescence detection by total internal reflection microscope requires surface passivation by polyethylene glycol (PEG) coating, which is labor intensive and is only good for one or two experiments. Here, we present an efficient and reliable protocol for generating and regenerating the PEG surface for multiple rounds of experiments (∼5–10 times) in the same channel. This protocol is very simple, robust, rapid, and versatile; i.e., multiple strategies can be implemented to regenerate different layers of surface. The regeneration strategy saves time, improves the cost effectiveness, and enhances the efficiency of single-molecule experiments. For complete details on the use and execution of this profile, please refer to Paul et al. (2021a). Regeneration of PEG-passivated slide is simple, quick, and cost effective Multiple experiments can be performed in a single channel Different strategies are implemented for different level of regeneration Regeneration leads to highly reproducible results
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Affiliation(s)
- Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA.,Physics Frontier Center, Center for the Physics of Living Cells, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
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12
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Paul T, Myong S. Helicase mediated vectorial folding of telomere G-quadruplex. Methods Enzymol 2022; 672:283-297. [DOI: 10.1016/bs.mie.2022.03.065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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De Rosa M, Johnson SA, Opresko PL. Roles for the 8-Oxoguanine DNA Repair System in Protecting Telomeres From Oxidative Stress. Front Cell Dev Biol 2021; 9:758402. [PMID: 34869348 PMCID: PMC8640134 DOI: 10.3389/fcell.2021.758402] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/27/2021] [Indexed: 11/27/2022] Open
Abstract
Telomeres are protective nucleoprotein structures that cap linear chromosome ends and safeguard genome stability. Progressive telomere shortening at each somatic cell division eventually leads to critically short and dysfunctional telomeres, which can contribute to either cellular senescence and aging, or tumorigenesis. Human reproductive cells, some stem cells, and most cancer cells, express the enzyme telomerase to restore telomeric DNA. Numerous studies have shown that oxidative stress caused by excess reactive oxygen species is associated with accelerated telomere shortening and dysfunction. Telomeric repeat sequences are remarkably susceptible to oxidative damage and are preferred sites for the production of the mutagenic base lesion 8-oxoguanine, which can alter telomere length homeostasis and integrity. Therefore, knowledge of the repair pathways involved in the processing of 8-oxoguanine at telomeres is important for advancing understanding of the pathogenesis of degenerative diseases and cancer associated with telomere instability. The highly conserved guanine oxidation (GO) system involves three specialized enzymes that initiate distinct pathways to specifically mitigate the adverse effects of 8-oxoguanine. Here we introduce the GO system and review the studies focused on investigating how telomeric 8-oxoguanine processing affects telomere integrity and overall genome stability. We also discuss newly developed technologies that target oxidative damage selectively to telomeres to investigate roles for the GO system in telomere stability.
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Affiliation(s)
- Mariarosaria De Rosa
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health and UPMC Hillman Cancer Center, Pittsburgh, PA, United States
| | - Samuel A Johnson
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health and UPMC Hillman Cancer Center, Pittsburgh, PA, United States
| | - Patricia L Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health and UPMC Hillman Cancer Center, Pittsburgh, PA, United States
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14
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Paul T, Liou W, Cai X, Opresko PL, Myong S. TRF2 promotes dynamic and stepwise looping of POT1 bound telomeric overhang. Nucleic Acids Res 2021; 49:12377-12393. [PMID: 34850123 PMCID: PMC8643667 DOI: 10.1093/nar/gkab1123] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/20/2021] [Accepted: 11/18/2021] [Indexed: 11/12/2022] Open
Abstract
Human telomeres are protected by shelterin proteins, but how telomeres maintain a dynamic structure remains elusive. Here, we report an unexpected activity of POT1 in imparting conformational dynamics of the telomere overhang, even at a monomer level. Strikingly, such POT1-induced overhang dynamics is greatly enhanced when TRF2 engages with the telomere duplex. Interestingly, TRF2, but not TRF2ΔB, recruits POT1-bound overhangs to the telomere ds/ss junction and induces a discrete stepwise movement up and down the axis of telomere duplex. The same steps are observed regardless of the length of the POT1-bound overhang, suggesting a tightly regulated conformational dynamic coordinated by TRF2 and POT1. TPP1 and TIN2 which physically connect POT1 and TRF2 act to generate a smooth movement along the axis of the telomere duplex. Our results suggest a plausible mechanism wherein telomeres maintain a dynamic structure orchestrated by shelterin.
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Affiliation(s)
- Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Wilson Liou
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Xinyi Cai
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Patricia L Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh, Hillman Cancer Center, 5117 Centre Avenue, Suite 2.6a, Pittsburgh, PA 15213, USA
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA.,Physics Frontier Center (Center for Physics of Living Cells), University of Illinois, 1110 W. Green St., Urbana, IL 61801, USA
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15
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An J, Yin M, Yin J, Wu S, Selby CP, Yang Y, Sancar A, Xu GL, Qian M, Hu J. Genome-wide analysis of 8-oxo-7,8-dihydro-2'-deoxyguanosine at single-nucleotide resolution unveils reduced occurrence of oxidative damage at G-quadruplex sites. Nucleic Acids Res 2021; 49:12252-12267. [PMID: 34788860 PMCID: PMC8643665 DOI: 10.1093/nar/gkab1022] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 09/28/2021] [Accepted: 10/13/2021] [Indexed: 02/06/2023] Open
Abstract
8-Oxo-7,8-dihydro-2′-deoxyguanosine (OG), one of the most common oxidative DNA damages, causes genome instability and is associated with cancer, neurological diseases and aging. In addition, OG and its repair intermediates can regulate gene transcription, and thus play a role in sensing cellular oxidative stress. However, the lack of methods to precisely map OG has hindered the study of its biological roles. Here, we developed a single-nucleotide resolution OG-sequencing method, named CLAPS-seq (Chemical Labeling And Polymerase Stalling Sequencing), to measure the genome-wide distribution of both exogenous and endogenous OGs with high specificity. Our data identified decreased OG occurrence at G-quadruplexes (G4s), in association with underrepresentation of OGs in promoters which have high GC content. Furthermore, we discovered that potential quadruplex sequences (PQSs) were hotspots of OGs, implying a role of non-G4-PQSs in OG-mediated oxidative stress response.
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Affiliation(s)
- Jiao An
- Shanghai Fifth People's Hospital, Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Mengdie Yin
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Jiayong Yin
- Institute of Pediatrics and Department of Hematology and Oncology, Children's Hospital of Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Sizhong Wu
- Shanghai Fifth People's Hospital, Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Christopher P Selby
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, NC 27599-7260, USA
| | - Yanyan Yang
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, NC 27599-7260, USA
| | - Aziz Sancar
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, NC 27599-7260, USA
| | - Guo-Liang Xu
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Maoxiang Qian
- Institute of Pediatrics and Department of Hematology and Oncology, Children's Hospital of Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
| | - Jinchuan Hu
- Shanghai Fifth People's Hospital, Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai 200032, China
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16
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Impact of G-Quadruplexes and Chronic Inflammation on Genome Instability: Additive Effects during Carcinogenesis. Genes (Basel) 2021; 12:genes12111779. [PMID: 34828385 PMCID: PMC8619830 DOI: 10.3390/genes12111779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/03/2021] [Accepted: 11/04/2021] [Indexed: 02/07/2023] Open
Abstract
Genome instability is an enabling characteristic of cancer, essential for cancer cell evolution. Hotspots of genome instability, from small-scale point mutations to large-scale structural variants, are associated with sequences that potentially form non-B DNA structures. G-quadruplex (G4) forming motifs are enriched at structural variant endpoints in cancer genomes. Chronic inflammation is a physiological state underlying cancer development, and oxidative DNA damage is commonly invoked to explain how inflammation promotes genome instability. We summarize where G4s and oxidative stress overlap, with a focus on DNA replication. Guanine has low ionization potential, making G4s vulnerable to oxidative damage. Impacts to G4 structure are dependent upon lesion type, location, and G4 conformation. Occasionally, G4s pose a challenge to replicative DNA polymerases, requiring specialized DNA polymerases to maintain genome stability. Therefore, chronic inflammation creates a dual challenge for DNA polymerases to maintain genome stability: faithful G4 synthesis and bypassing unrepaired oxidative lesions. Inflammation is also accompanied by global transcriptome changes that may impact mutagenesis. Several studies suggest a regulatory role for G4s within cancer- and inflammatory-related gene promoters. We discuss the extent to which inflammation could influence gene regulation by G4s, thereby impacting genome instability, and highlight key areas for new investigation.
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17
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Bandyopadhyay D, Mishra PP. Decoding the Structural Dynamics and Conformational Alternations of DNA Secondary Structures by Single-Molecule FRET Microspectroscopy. Front Mol Biosci 2021; 8:725541. [PMID: 34540899 PMCID: PMC8446445 DOI: 10.3389/fmolb.2021.725541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/30/2021] [Indexed: 12/02/2022] Open
Abstract
In addition to the canonical double helix form, DNA is known to be extrapolated into several other secondary structural patterns involving themselves in inter- and intramolecular type hydrogen bonding. The secondary structures of nucleic acids go through several stages of multiple, complex, and interconvertible heterogeneous conformations. The journey of DNA through these conformers has significant importance and has been monitored thoroughly to establish qualitative and quantitative information about the transition between the unfolded, folded, misfolded, and partially folded states. During this structural interconversion, there always exist specific populations of intermediates, which are short-lived or sometimes even do not accumulate within a heterogeneous population and are challenging to characterize using conventional ensemble techniques. The single-molecule FRET(sm-FRET) microspectroscopic method has the advantages to overcome these limitations and monitors biological phenomena transpiring at a measurable high rate and balanced stochastically over time. Thus, tracing the time trajectory of a particular molecule enables direct measurement of the rate constant of each transition step, including the intermediates that are hidden in the ensemble level due to their low concentrations. This review is focused on the advantages of the employment of single-molecule Forster's resonance energy transfer (sm-FRET), which is worthwhile to access the dynamic architecture and structural transition of various secondary structures that DNA adopts, without letting the donor of one molecule to cross-talk with the acceptor of any other. We have emphasized the studies performed to explore the states of folding and unfolding of several nucleic acid secondary structures, for example, the DNA hairpin, Holliday junction, G-quadruplex, and i-motif.
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Affiliation(s)
- Debolina Bandyopadhyay
- Single-Molecule Biophysics Lab, Chemical Sciences Division, Saha Institute of Nuclear Physics, Kolkata, India
- HBNI, Mumbai, India
| | - Padmaja P. Mishra
- Single-Molecule Biophysics Lab, Chemical Sciences Division, Saha Institute of Nuclear Physics, Kolkata, India
- HBNI, Mumbai, India
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18
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How DNA damage and non-canonical nucleotides alter the telomerase catalytic cycle. DNA Repair (Amst) 2021; 107:103198. [PMID: 34371388 DOI: 10.1016/j.dnarep.2021.103198] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 01/01/2023]
Abstract
Telomeres at the ends of linear chromosomes are essential for genome maintenance and sustained cellular proliferation, but shorten with each cell division. Telomerase, a specialized reverse transcriptase with its own integral RNA template, compensates for this by lengthening the telomeric 3' single strand overhang. Mammalian telomerase has the unique ability to processively synthesize multiple GGTTAG repeats, by translocating along its product and reiteratively copying the RNA template, termed repeat addition processivity (RAP). This unusual form of processivity is distinct from the nucleotide addition processivity (NAP) shared by all other DNA polymerases. In this review, we focus on the minimally active human telomerase catalytic core consisting of the telomerase reverse transcriptase (TERT) and the integral RNA (TR), which catalyzes DNA synthesis. We review the mechanisms by which oxidatively damaged nucleotides, and anti-viral and anti-cancer nucleotide drugs affect the telomerase catalytic cycle. Finally, we offer perspective on how we can leverage telomerase's unique properties, and advancements in understanding of telomerase catalytic mechanism, to selectively manipulate telomerase activity with therapeutics, particularly in cancer treatment.
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19
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Liu H, Lu YN, Paul T, Periz G, Banco MT, Ferré-D'Amaré AR, Rothstein JD, Hayes LR, Myong S, Wang J. A Helicase Unwinds Hexanucleotide Repeat RNA G-Quadruplexes and Facilitates Repeat-Associated Non-AUG Translation. J Am Chem Soc 2021; 143:7368-7379. [PMID: 33855846 DOI: 10.1021/jacs.1c00131] [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
The expansion of a hexanucleotide repeat GGGGCC (G4C2) in the C9orf72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The G4C2 expansion leads to repeat-associated non-AUG (RAN) translation and the production of toxic dipeptide repeat (DPR) proteins, but the mechanisms of RAN translation remain enigmatic. Here, we report that the RNA helicase DHX36 is a robust positive regulator of C9orf72 RAN translation. DHX36 has a high affinity for the G4C2 repeat RNA, preferentially binds to the repeat RNA's G-quadruplex conformation, and efficiently unwinds the G4C2 G-quadruplex structures. Native DHX36 interacts with the G4C2 repeat RNA and is essential for effective RAN translation in the cell. In induced pluripotent stem cells and differentiated motor neurons derived from C9orf72-linked ALS patients, reducing DHX36 significantly decreased the levels of endogenous DPR proteins. DHX36 is also aberrantly upregulated in tissues of C9orf72-linked ALS patients. These results indicate that DHX36 facilitates C9orf72 RAN translation by resolving repeat RNA G-quadruplex structures and may be a potential target for therapeutic intervention.
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Affiliation(s)
- Honghe Liu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| | - Yu-Ning Lu
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| | - Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Goran Periz
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
| | - Michael T Banco
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, United States
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, Maryland 20892, United States
| | - Jeffrey D Rothstein
- Brain Science Institute and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Lindsey R Hayes
- Brain Science Institute and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, United States
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jiou Wang
- Department of Biochemistry and Molecular Biology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland 21205, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, Maryland 21205, United States
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20
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Bielskutė S, Plavec J, Podbevšek P. Oxidative lesions modulate G-quadruplex stability and structure in the human BCL2 promoter. Nucleic Acids Res 2021; 49:2346-2356. [PMID: 33638996 PMCID: PMC7913773 DOI: 10.1093/nar/gkab057] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/08/2021] [Accepted: 01/22/2021] [Indexed: 01/08/2023] Open
Abstract
Misregulation of BCL2 expression has been observed with many diseases and is associated with cellular exposure to reactive oxygen species. A region upstream of the P1 promoter in the human BCL2 gene plays a major role in regulating transcription. This G/C-rich region is highly polymorphic and capable of forming G-quadruplex structures. Herein we report that an oxidative event simulated with an 8-oxo-7,8-dihydroguanine (oxoG) substitution within a long G-tract results in a reduction of structural polymorphism. Surprisingly, oxoG within a 25-nt construct boosts thermal stability of the resulting G-quadruplex. This is achieved by distinct hydrogen bonding properties of oxoG, which facilitate formation of an antiparallel basket-type G-quadruplex with a three G-quartet core and a G·oxoG·C base triad. While oxoG has previously been considered detrimental for G-quadruplex formation, its stabilizing effect within a promoter described in this study suggests a potential novel regulatory role of oxidative stress in general and specifically in BCL2 gene transcription.
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Affiliation(s)
- Stasė Bielskutė
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia.,EN-FIST Center of Excellence, Trg OF 13, SI-1000 Ljubljana, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Peter Podbevšek
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
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21
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Paul T, Ha T, Myong S. Regeneration of PEG slide for multiple rounds of single-molecule measurements. Biophys J 2021; 120:1788-1799. [PMID: 33675764 DOI: 10.1016/j.bpj.2021.02.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/10/2021] [Accepted: 02/23/2021] [Indexed: 10/22/2022] Open
Abstract
Single-molecule fluorescence detection of protein and other biomolecules requires a polyethylene glycol (PEG)-passivated surface. Individual channels on a PEG-passivated slide are typically used only a few times, limiting the number of experiments per slide. Here, we report several strategies for regenerating PEG surfaces for multiple rounds of experiments. First, we show regeneration of DNA- or RNA-tethered surfaces by washing out the bound protein by 0.1% sodium dodecyl sulfate, which is significantly more effective than 6 M urea, 6 M GdmCl, or 100 μM proteinase K. Strikingly, 10 consecutive experiments in five different systems produced indistinguishable results both in molecule count and protein activity. Second, duplexed DNA unwound by helicase or denatured by 50 mM NaOH was reannealed with a complementary strand to regenerate the duplexed substrate with an exceptionally high recovery rate. Third, the biotin-PEG layer was regenerated by using 7 M NaOH to strip off NeutrAvidin, which can be reapplied for additional experiments. We demonstrate five cycles of regenerating antibody immobilized surface by which three different protein activity was measured. Altogether, our methods represent reliable and reproducible yet simple and rapid strategies that will enhance the efficiency of single-molecule experiments.
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Affiliation(s)
- Tapas Paul
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland
| | - Taekjip Ha
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland; Physics Frontier Center (Center for Physics of Living Cells), University of Illinois, Urbana, Illinois; Howard Hughes Medical Institute, Johns Hopkins University, Baltimore, Maryland
| | - Sua Myong
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland; Physics Frontier Center (Center for Physics of Living Cells), University of Illinois, Urbana, Illinois.
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22
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Medina E, R Latham D, Sanabria H. Unraveling protein's structural dynamics: from configurational dynamics to ensemble switching guides functional mesoscale assemblies. Curr Opin Struct Biol 2021; 66:129-138. [PMID: 33246199 PMCID: PMC7965259 DOI: 10.1016/j.sbi.2020.10.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 12/18/2022]
Abstract
Evidence regarding protein structure and function manifest the imperative role that dynamics play in proteins, underlining reconsideration of the unanimated sequence-to-structure-to-function paradigm. Structural dynamics portray a heterogeneous energy landscape described by conformational ensembles where each structural representation can be responsible for unique functions or enable macromolecular assemblies. Using the human p27/Cdk2/Cyclin A ternary complex as an example, we highlight the vital role of intramolecular and intermolecular dynamics for target recognition, binding, and inhibition as a critical modulator of cell division. Rapidly sampling configurations is critical for the population of different conformational ensembles encoding functional roles. To garner this knowledge, we present how the integration of (sub)ensemble and single-molecule fluorescence spectroscopy with molecular dynamic simulations can characterize structural dynamics linking the heterogeneous ensembles to function. The incorporation of dynamics into the sequence-to-structure-to-function paradigm promises to assist in tackling various challenges, including understanding the formation and regulation of mesoscale assemblies inside cells.
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Affiliation(s)
- Exequiel Medina
- Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Casilla 653, Santiago 7800003, Chile; Department of Physics and Astronomy, Clemson University, Clemson 29634, United States
| | - Danielle R Latham
- Department of Physics and Astronomy, Clemson University, Clemson 29634, United States
| | - Hugo Sanabria
- Department of Physics and Astronomy, Clemson University, Clemson 29634, United States.
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