1
|
Dong HL, Zhang C, Dai L, Zhang Y, Zhang XH, Tan ZJ. The origin of different bending stiffness between double-stranded RNA and DNA revealed by magnetic tweezers and simulations. Nucleic Acids Res 2024; 52:2519-2529. [PMID: 38321947 PMCID: PMC10954459 DOI: 10.1093/nar/gkae063] [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: 06/14/2023] [Revised: 01/16/2024] [Accepted: 01/19/2024] [Indexed: 02/08/2024] Open
Abstract
The subtle differences in the chemical structures of double-stranded (ds) RNA and DNA lead to significant variations in their biological roles and medical implications, largely due to their distinct biophysical properties, such as bending stiffness. Although it is well known that A-form dsRNA is stiffer than B-form dsDNA under physiological salt conditions, the underlying cause of this difference remains unclear. In this study, we employ high-precision magnetic-tweezer experiments along with molecular dynamics simulations and reveal that the relative bending stiffness between dsRNA and dsDNA is primarily determined by the structure- and salt-concentration-dependent ion distribution around their helical structures. At near-physiological salt conditions, dsRNA shows a sparser ion distribution surrounding its phosphate groups compared to dsDNA, causing its greater stiffness. However, at very high monovalent salt concentrations, phosphate groups in both dsRNA and dsDNA become fully neutralized by excess ions, resulting in a similar intrinsic bending persistence length of approximately 39 nm. This similarity in intrinsic bending stiffness of dsRNA and dsDNA is coupled to the analogous fluctuations in their total groove widths and further coupled to the similar fluctuation of base-pair inclination, despite their distinct A-form and B-form helical structures.
Collapse
Affiliation(s)
- Hai-Long Dong
- School of Physics and Technology, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, China
| | - Chen Zhang
- School of Physics and Technology, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, China
| | - Liang Dai
- Department of Physics, City University of Hong Kong, Hong Kong 999077, China
| | - Yan Zhang
- Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan 430072, China
| | - Xing-Hua Zhang
- School of Physics and Technology, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, China
| | - Zhi-Jie Tan
- School of Physics and Technology, College of Life Sciences, Renmin Hospital of Wuhan University, Wuhan University, Wuhan 430072, China
| |
Collapse
|
2
|
Roldán-Piñero C, Luengo-Márquez J, Assenza S, Pérez R. Systematic Comparison of Atomistic Force Fields for the Mechanical Properties of Double-Stranded DNA. J Chem Theory Comput 2024; 20:2261-2272. [PMID: 38411091 PMCID: PMC10938644 DOI: 10.1021/acs.jctc.3c01089] [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: 10/02/2023] [Revised: 02/14/2024] [Accepted: 02/14/2024] [Indexed: 02/28/2024]
Abstract
The response of double-stranded DNA to external mechanical stress plays a central role in its interactions with the protein machinery in the cell. Modern atomistic force fields have been shown to provide highly accurate predictions for the fine structural features of the duplex. In contrast, and despite their pivotal function, less attention has been devoted to the accuracy of the prediction of the elastic parameters. Several reports have addressed the flexibility of double-stranded DNA via all-atom molecular dynamics, yet the collected information is insufficient to have a clear understanding of the relative performance of the various force fields. In this work, we fill this gap by performing a systematic study in which several systems, characterized by different sequence contexts, are simulated with the most popular force fields within the AMBER family, bcs1 and OL15, as well as with CHARMM36. Analysis of our results, together with their comparison with previous work focused on bsc0, allows us to unveil the differences in the predicted rigidity between the newest force fields and suggests a roadmap to test their performance against experiments. In the case of the stretch modulus, we reconcile these differences, showing that a single mapping between sequence-dependent conformation and elasticity via the crookedness parameter captures simultaneously the results of all force fields, supporting the key role of crookedness in the mechanical response of double-stranded DNA.
Collapse
Affiliation(s)
- Carlos Roldán-Piñero
- Departamento
de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Juan Luengo-Márquez
- Departamento
de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Instituto
Nicolás Cabrera, Universidad Autónoma
de Madrid, E-28049 Madrid, Spain
| | - Salvatore Assenza
- Departamento
de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Instituto
Nicolás Cabrera, Universidad Autónoma
de Madrid, E-28049 Madrid, Spain
- Condensed
Matter Physics Center (IFIMAC), Universidad
Autónoma de Madrid, E-28049 Madrid, Spain
| | - Rubén Pérez
- Departamento
de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
- Condensed
Matter Physics Center (IFIMAC), Universidad
Autónoma de Madrid, E-28049 Madrid, Spain
| |
Collapse
|
3
|
Dohnalová H, Matoušková E, Lankaš F. Temperature-dependent elasticity of DNA, RNA, and hybrid double helices. Biophys J 2024; 123:572-583. [PMID: 38340722 PMCID: PMC10938081 DOI: 10.1016/j.bpj.2024.01.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 12/19/2023] [Accepted: 01/26/2024] [Indexed: 02/12/2024] Open
Abstract
Nucleic acid double helices in their DNA, RNA, and DNA-RNA hybrid form play a fundamental role in biology and are main building blocks of artificial nanostructures, but how their properties depend on temperature remains poorly understood. Here, we report thermal dependence of dynamic bending persistence length, twist rigidity, stretch modulus, and twist-stretch coupling for DNA, RNA, and hybrid duplexes between 7°C and 47°C. The results are based on all-atom molecular dynamics simulations using different force field parameterizations. We first demonstrate that unrestrained molecular dynamics can reproduce experimentally known mechanical properties of the duplexes at room temperature. Beyond experimentally known features, we also infer the twist rigidity and twist-stretch coupling of the hybrid duplex. As for the temperature dependence, we found that increasing temperature softens all the duplexes with respect to bending, twisting, and stretching. The relative decrease of the stretch moduli is 0.003-0.004/°C, similar for all the duplex variants despite their very different stretching stiffness, whereas RNA twist stiffness decreases by 0.003/°C, and smaller values are found for the other elastic moduli. The twist-stretch couplings are nearly unaffected by temperature. The stretching, bending, and twisting stiffness all include an important entropic component. Relation of our results to the two-state model of DNA flexibility is discussed. Our work provides temperature-dependent elasticity of nucleic acid duplexes at the microsecond scale relevant for initial stages of protein binding.
Collapse
Affiliation(s)
- Hana Dohnalová
- Department of Informatics and Chemistry, University of Chemistry and Technology Prague, Praha 6, Czech Republic
| | - Eva Matoušková
- Department of Informatics and Chemistry, University of Chemistry and Technology Prague, Praha 6, Czech Republic
| | - Filip Lankaš
- Department of Informatics and Chemistry, University of Chemistry and Technology Prague, Praha 6, Czech Republic.
| |
Collapse
|
4
|
Li Y, Chen R, Zhou B, Dong Y, Liu D. Rational Design of DNA Hydrogels Based on Molecular Dynamics of Polymers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2307129. [PMID: 37820719 DOI: 10.1002/adma.202307129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 10/03/2023] [Indexed: 10/13/2023]
Abstract
In recent years, DNA has emerged as a fascinating building material to engineer hydrogel due to its excellent programmability, which has gained considerable attention in biomedical applications. Understanding the structure-property relationship and underlying molecular determinants of DNA hydrogel is essential to precisely tailor its macroscopic properties at molecular level. In this review, the rational design principles of DNA molecular networks based on molecular dynamics of polymers on the temporal scale, which can be engineered via the backbone rigidity and crosslinking kinetics, are highlighted. By elucidating the underlying molecular mechanisms and theories, it is aimed to provide a comprehensive overview of how the tunable DNA backbone rigidity and the crosslinking kinetics lead to desirable macroscopic properties of DNA hydrogels, including mechanical properties, diffusive permeability, swelling behaviors, and dynamic features. Furthermore, it is also discussed how the tunable macroscopic properties make DNA hydrogels promising candidates for biomedical applications, such as cell culture, tissue engineering, bio-sensing, and drug delivery.
Collapse
Affiliation(s)
- Yujie Li
- Engineering Research Center of Advanced Rare Earth Materials, (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Ruofan Chen
- Engineering Research Center of Advanced Rare Earth Materials, (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Bini Zhou
- Engineering Research Center of Advanced Rare Earth Materials, (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| | - Yuanchen Dong
- CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Dongsheng Liu
- Engineering Research Center of Advanced Rare Earth Materials, (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China
| |
Collapse
|
5
|
Chen YT, Yang H, Chu JW. Mechanical codes of chemical-scale specificity in DNA motifs. Chem Sci 2023; 14:10155-10166. [PMID: 37772098 PMCID: PMC10529945 DOI: 10.1039/d3sc01671d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 08/28/2023] [Indexed: 09/30/2023] Open
Abstract
In gene transcription, certain sequences of double-stranded (ds)DNA play a vital role in nucleosome positioning and expression initiation. That dsDNA is deformed to various extents in these processes leads us to ask: Could the genomic DNA also have sequence specificity in its chemical-scale mechanical properties? We approach this question using statistical machine learning to determine the rigidity between DNA chemical moieties. What emerges for the polyA, polyG, TpA, and CpG sequences studied here is a unique trigram that contains the quantitative mechanical strengths between bases and along the backbone. In a way, such a sequence-dependent trigram could be viewed as a DNA mechanical code. Interestingly, we discover a compensatory competition between the axial base-stacking interaction and the transverse base-pairing interaction, and such a reciprocal relationship constitutes the most discriminating feature of the mechanical code. Our results also provide chemical-scale understanding for experimental observables. For example, the long polyA persistence length is shown to have strong base stacking while its complement (polyAc) exhibits high backbone rigidity. The mechanical code concept enables a direct reading of the physical interactions encoded in the sequence which, with further development, is expected to shed new light on DNA allostery and DNA-binding drugs.
Collapse
Affiliation(s)
- Yi-Tsao Chen
- Institute of Bioinformatics and Systems Biology, National Yang Ming Chiao Tung University Hsinchu 30010 Taiwan Republic of China
| | - Haw Yang
- Department of Chemistry, Princeton University Princeton NJ 08544 USA
| | - Jhih-Wei Chu
- Institute of Bioinformatics and Systems Biology, National Yang Ming Chiao Tung University Hsinchu 30010 Taiwan Republic of China
- Department of Biological Science and Technology, Institute of Molecular Medicine and Bioengineering, Center for Intelligent Drug Systems and Smart Bio-devices (IDS2B), National Yang Ming Chiao Tung University Hsinchu 30010 Taiwan Republic of China
| |
Collapse
|
6
|
Luengo-Márquez J, Zalvide-Pombo J, Pérez R, Assenza S. Force-dependent elasticity of nucleic acids. NANOSCALE 2023; 15:6738-6744. [PMID: 36942727 DOI: 10.1039/d2nr06324g] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The functioning of double-stranded (ds) nucleic acids (NAs) in cellular processes is strongly mediated by their elastic response. These processes involve proteins that interact with dsDNA or dsRNA and distort their structures. The perturbation of the elasticity of NAs arising from these deformations is not properly considered by most theoretical frameworks. In this work, we introduce a novel method to assess the impact of mechanical stress on the elastic response of dsDNA and dsRNA through the analysis of the fluctuations of the double helix. Application of this approach to atomistic simulations reveals qualitative differences in the force dependence of the mechanical properties of dsDNA with respect to those of dsRNA, which we relate to structural features of these molecules by means of physically-sound minimalistic models.
Collapse
Affiliation(s)
- Juan Luengo-Márquez
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
- Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Juan Zalvide-Pombo
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
| | - Rubén Pérez
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.
| | - Salvatore Assenza
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain.
- Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| |
Collapse
|
7
|
Optical Tweezers to Force Information out of Biological and Synthetic Systems One Molecule at a Time. BIOPHYSICA 2022. [DOI: 10.3390/biophysica2040047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Over the last few decades, in vitro single-molecule manipulation techniques have enabled the use of force and displacement as controlled variables in biochemistry. Measuring the effect of mechanical force on the real-time kinetics of a biological process gives us access to the rates, equilibrium constants and free-energy landscapes of the mechanical steps of the reaction; this information is not accessible by ensemble assays. Optical tweezers are the current method of choice in single-molecule manipulation due to their versatility, high force and spatial and temporal resolutions. The aim of this review is to describe the contributions of our lab in the single-molecule manipulation field. We present here several optical tweezers assays refined in our laboratory to probe the dynamics and mechano-chemical properties of biological molecular motors and synthetic molecular devices at the single-molecule level.
Collapse
|
8
|
Shi WT, Zhang B, Li ML, Liu KH, Jiao J, Tian CF. The convergent xenogeneic silencer MucR predisposes α-proteobacteria to integrate AT-rich symbiosis genes. Nucleic Acids Res 2022; 50:8580-8598. [PMID: 36007892 PMCID: PMC9410896 DOI: 10.1093/nar/gkac664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 11/16/2022] Open
Abstract
Bacterial adaptation is largely shaped by horizontal gene transfer, xenogeneic silencing mediated by lineage-specific DNA bridgers (H-NS, Lsr2, MvaT and Rok), and various anti-silencing mechanisms. No xenogeneic silencing DNA bridger is known for α-proteobacteria, from which mitochondria evolved. By investigating α-proteobacterium Sinorhizobium fredii, a facultative legume microsymbiont, here we report the conserved zinc-finger bearing MucR as a novel xenogeneic silencing DNA bridger. Self-association mediated by its N-terminal domain (NTD) is required for DNA–MucR–DNA bridging complex formation, maximizing MucR stability, transcriptional silencing, and efficient symbiosis in legume nodules. Essential roles of NTD, CTD (C-terminal DNA-binding domain), or full-length MucR in symbiosis can be replaced by non-homologous NTD, CTD, or full-length protein of H-NS from γ-proteobacterium Escherichia coli, while NTD rather than CTD of Lsr2 from Gram-positive Mycobacterium tuberculosis can replace the corresponding domain of MucR in symbiosis. Chromatin immunoprecipitation sequencing reveals similar recruitment profiles of H-NS, MucR and various functional chimeric xenogeneic silencers across the multipartite genome of S. fredii, i.e. preferring AT-rich genomic islands and symbiosis plasmid with key symbiosis genes as shared targets. Collectively, the convergently evolved DNA bridger MucR predisposed α-proteobacteria to integrate AT-rich foreign DNA including symbiosis genes, horizontal transfer of which is strongly selected in nature.
Collapse
Affiliation(s)
- Wen-Tao Shi
- State Key Laboratory of Agrobiotechnology, and College of Biological Sciences, China Agricultural University , Beijing , China
- MOA Key Laboratory of Soil Microbiology, and Rhizobium Research Center, China Agricultural University , Beijing , China
| | - Biliang Zhang
- State Key Laboratory of Agrobiotechnology, and College of Biological Sciences, China Agricultural University , Beijing , China
- MOA Key Laboratory of Soil Microbiology, and Rhizobium Research Center, China Agricultural University , Beijing , China
| | - Meng-Lin Li
- State Key Laboratory of Agrobiotechnology, and College of Biological Sciences, China Agricultural University , Beijing , China
- MOA Key Laboratory of Soil Microbiology, and Rhizobium Research Center, China Agricultural University , Beijing , China
| | - Ke-Han Liu
- State Key Laboratory of Agrobiotechnology, and College of Biological Sciences, China Agricultural University , Beijing , China
- MOA Key Laboratory of Soil Microbiology, and Rhizobium Research Center, China Agricultural University , Beijing , China
| | - Jian Jiao
- State Key Laboratory of Agrobiotechnology, and College of Biological Sciences, China Agricultural University , Beijing , China
- MOA Key Laboratory of Soil Microbiology, and Rhizobium Research Center, China Agricultural University , Beijing , China
| | - Chang-Fu Tian
- State Key Laboratory of Agrobiotechnology, and College of Biological Sciences, China Agricultural University , Beijing , China
- MOA Key Laboratory of Soil Microbiology, and Rhizobium Research Center, China Agricultural University , Beijing , China
| |
Collapse
|
9
|
Ruggiero E, Lavezzo E, Grazioli M, Zanin I, Marušič M, Plavec J, Richter SN, Toppo S. Human Virus Genomes Are Enriched in Conserved Adenine/Thymine/Uracil Multiple Tracts That Pause Polymerase Progression. Front Microbiol 2022; 13:915069. [PMID: 35722311 PMCID: PMC9198555 DOI: 10.3389/fmicb.2022.915069] [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: 04/07/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
The DNA secondary structures that deviate from the classic Watson and Crick base pairing are increasingly being reported to form transiently in the cell and regulate specific cellular mechanisms. Human viruses are cell parasites that have evolved mechanisms shared with the host cell to support their own replication and spreading. Contrary to human host cells, viruses display a diverse array of nucleic acid types, which include DNA or RNA in single-stranded or double-stranded conformations. This heterogeneity improves the possible occurrence of non-canonical nucleic acid structures. We have previously shown that human virus genomes are enriched in G-rich sequences that fold in four-stranded nucleic acid secondary structures, the G-quadruplexes.Here, by extensive bioinformatics analysis on all available genomes, we showed that human viruses are enriched in highly conserved multiple A (and T or U) tracts, with such an array that they could in principle form quadruplex structures. By circular dichroism, NMR, and Taq polymerase stop assays, we proved that, while A/T/U-quadruplexes do not form, these tracts still display biological significance, as they invariably trigger polymerase pausing within two bases from the A/T/U tract. “A” bases display the strongest effect. Most of the identified A-tracts are in the coding strand, both at the DNA and RNA levels, suggesting their possible relevance during viral translation. This study expands on the presence and mechanism of nucleic acid secondary structures in human viruses and provides a new direction for antiviral research.
Collapse
Affiliation(s)
| | - Enrico Lavezzo
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Marco Grazioli
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Irene Zanin
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Maja Marušič
- Slovenian NMR Centre, National Institute of Chemistry, Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Ljubljana, Slovenia
| | - Sara N Richter
- Department of Molecular Medicine, University of Padua, Padua, Italy
| | - Stefano Toppo
- Department of Molecular Medicine, University of Padua, Padua, Italy.,CRIBI Biotechnology Center, University of Padua, Padua, Italy
| |
Collapse
|
10
|
Assenza S, Pérez R. Accurate Sequence-Dependent Coarse-Grained Model for Conformational and Elastic Properties of Double-Stranded DNA. J Chem Theory Comput 2022; 18:3239-3256. [PMID: 35394775 PMCID: PMC9097290 DOI: 10.1021/acs.jctc.2c00138] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
![]()
We introduce MADna,
a sequence-dependent coarse-grained model of
double-stranded DNA (dsDNA), where each nucleotide is described by
three beads localized at the sugar, at the base moiety, and at the
phosphate group, respectively. The sequence dependence is included
by considering a step-dependent parametrization of the bonded interactions,
which are tuned in order to reproduce the values of key observables
obtained from exhaustive atomistic simulations from the literature.
The predictions of the model are benchmarked against an independent
set of all-atom simulations, showing that it captures with high fidelity
the sequence dependence of conformational and elastic features beyond
the single step considered in its formulation. A remarkably good agreement
with experiments is found for both sequence-averaged and sequence-dependent
conformational and elastic features, including the stretching and
torsion moduli, the twist–stretch and twist–bend couplings,
the persistence length, and the helical pitch. Overall, for the inspected
quantities, the model has a precision comparable to atomistic simulations,
hence providing a reliable coarse-grained description for the rationalization
of single-molecule experiments and the study of cellular processes
involving dsDNA. Owing to the simplicity of its formulation, MADna
can be straightforwardly included in common simulation engines. Particularly,
an implementation of the model in LAMMPS is made available on an online
repository to ease its usage within the DNA research community.
Collapse
|
11
|
Bell NAW, Molloy JE. Efficient golden gate assembly of DNA constructs for single molecule force spectroscopy and imaging. Nucleic Acids Res 2022; 50:e77. [PMID: 35489063 PMCID: PMC9303394 DOI: 10.1093/nar/gkac300] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 03/18/2022] [Accepted: 04/13/2022] [Indexed: 01/01/2023] Open
Abstract
Single-molecule techniques such as optical tweezers and fluorescence imaging are powerful tools for probing the biophysics of DNA and DNA-protein interactions. The application of these methods requires efficient approaches for creating designed DNA structures with labels for binding to a surface or microscopic beads. In this paper, we develop a simple and fast technique for making a diverse range of such DNA constructs by combining PCR amplicons and synthetic oligonucleotides using golden gate assembly rules. We demonstrate high yield fabrication of torsionally-constrained duplex DNA up to 10 kbp in length and a variety of DNA hairpin structures. We also show how tethering to a cross-linked antibody substrate significantly enhances measurement lifetime under high force. This rapid and adaptable fabrication method streamlines the assembly of DNA constructs for single molecule biophysics.
Collapse
|
12
|
The Facts and Family Secrets of Plasmids That Replicate via the Rolling-Circle Mechanism. Microbiol Mol Biol Rev 2021; 86:e0022220. [PMID: 34878299 DOI: 10.1128/mmbr.00222-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Plasmids are self-replicative DNA elements that are transferred between bacteria. Plasmids encode not only antibiotic resistance genes but also adaptive genes that allow their hosts to colonize new niches. Plasmid transfer is achieved by conjugation (or mobilization), phage-mediated transduction, and natural transformation. Thousands of plasmids use the rolling-circle mechanism for their propagation (RCR plasmids). They are ubiquitous, have a high copy number, exhibit a broad host range, and often can be mobilized among bacterial species. Based upon the replicon, RCR plasmids have been grouped into several families, the best known of them being pC194 and pUB110 (Rep_1 family), pMV158 and pE194 (Rep_2 family), and pT181 and pC221 (Rep_trans family). Genetic traits of RCR plasmids are analyzed concerning (i) replication mediated by a DNA-relaxing initiator protein and its interactions with the cognate DNA origin, (ii) lagging-strand origins of replication, (iii) antibiotic resistance genes, (iv) mobilization functions, (v) replication control, performed by proteins and/or antisense RNAs, and (vi) the participating host-encoded functions. The mobilization functions include a relaxase initiator of transfer (Mob), an origin of transfer, and one or two small auxiliary proteins. There is a family of relaxases, the MOBV family represented by plasmid pMV158, which has been revisited and updated. Family secrets, like a putative open reading frame of unknown function, are reported. We conclude that basic research on RCR plasmids is of importance, and our perspectives contemplate the concept of One Earth because we should incorporate bacteria into our daily life by diminishing their virulence and, at the same time, respecting their genetic diversity.
Collapse
|
13
|
Dohnalová H, Lankaš F. Deciphering the mechanical properties of
B‐DNA
duplex. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2021. [DOI: 10.1002/wcms.1575] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Hana Dohnalová
- Department of Informatics and Chemistry University of Chemistry and Technology Prague Praha 6 Czech Republic
| | - Filip Lankaš
- Department of Informatics and Chemistry University of Chemistry and Technology Prague Praha 6 Czech Republic
| |
Collapse
|
14
|
DNA sequence-dependent positioning of the linker histone in a nucleosome: A single-pair FRET study. Biophys J 2021; 120:3747-3763. [PMID: 34293303 DOI: 10.1016/j.bpj.2021.07.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/25/2021] [Accepted: 07/13/2021] [Indexed: 01/01/2023] Open
Abstract
Linker histones (LHs) bind to nucleosomes with their globular domain (gH) positioned in either an on- or an off-dyad binding mode. Here, we study the effect of the linker DNA (L-DNA) sequence on the binding of a full-length LH, Xenopus laevis H1.0b, to a Widom 601 nucleosome core particle (NCP) flanked by two 40 bp long L-DNA arms, by single-pair FRET spectroscopy. We varied the sequence of the 11 bp of L-DNA adjoining the NCP on either side, making the sequence either A-tract, purely GC, or mixed with 64% AT. The labeled gH consistently exhibited higher FRET efficiency with the labeled L-DNA containing the A-tract than that with the pure-GC stretch, even when the stretches were swapped. However, it did not exhibit higher FRET efficiency with the L-DNA containing 64% AT-rich mixed DNA when compared to the pure-GC stretch. We explain our observations with a model that shows that the gH binds on dyad and that two arginines mediate recognition of the A-tract via its characteristically narrow minor groove. To investigate whether this on-dyad minor groove-based recognition was distinct from previously identified off-dyad major groove-based recognition, a nucleosome was designed with A-tracts on both the L-DNA arms. One A-tract was complementary to thymine and the other to deoxyuridine. The major groove of the thymine-tract was lined with methyl groups that were absent from the major groove of the deoxyuridine tract. The gH exhibited similar FRET for both these A-tracts, suggesting that it does not interact with the thymine methyl groups exposed on the major groove. Our observations thus complement previous studies that suggest that different LH isoforms may employ different ways of recognizing AT-rich DNA and A-tracts. This adaptability may enable the LH to universally compact scaffold-associated regions and constitutive heterochromatin, which are rich in such sequences.
Collapse
|
15
|
Balaguer FDA, Aicart-Ramos C, Fisher GL, de Bragança S, Martin-Cuevas EM, Pastrana CL, Dillingham MS, Moreno-Herrero F. CTP promotes efficient ParB-dependent DNA condensation by facilitating one-dimensional diffusion from parS. eLife 2021; 10:67554. [PMID: 34250901 PMCID: PMC8299390 DOI: 10.7554/elife.67554] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 07/09/2021] [Indexed: 12/19/2022] Open
Abstract
Faithful segregation of bacterial chromosomes relies on the ParABS partitioning system and the SMC complex. In this work, we used single-molecule techniques to investigate the role of cytidine triphosphate (CTP) binding and hydrolysis in the critical interaction between centromere-like parS DNA sequences and the ParB CTPase. Using a combined optical tweezers confocal microscope, we observe the specific interaction of ParB with parS directly. Binding around parS is enhanced by the presence of CTP or the non-hydrolysable analogue CTPγS. However, ParB proteins are also detected at a lower density in distal non-specific DNA. This requires the presence of a parS loading site and is prevented by protein roadblocks, consistent with one-dimensional diffusion by a sliding clamp. ParB diffusion on non-specific DNA is corroborated by direct visualization and quantification of movement of individual quantum dot labelled ParB. Magnetic tweezers experiments show that the spreading activity, which has an absolute requirement for CTP binding but not hydrolysis, results in the condensation of parS-containing DNA molecules at low nanomolar protein concentrations.
Collapse
Affiliation(s)
- Francisco de Asis Balaguer
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Clara Aicart-Ramos
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Gemma Lm Fisher
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, United Kingdom
| | - Sara de Bragança
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Eva M Martin-Cuevas
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Cesar L Pastrana
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Mark Simon Dillingham
- DNA:Protein Interactions Unit, School of Biochemistry, Biomedical Sciences Building, University of Bristol, University Walk, Bristol, United Kingdom
| | - Fernando Moreno-Herrero
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| |
Collapse
|
16
|
Abstract
DNA dynamics can only be understood by taking into account its complex mechanical behavior at different length scales. At the micrometer level, the mechanical properties of single DNA molecules have been well-characterized by polymer models and are commonly quantified by a persistence length of 50 nm (~150 bp). However, at the base pair level (~3.4 Å), the dynamics of DNA involves complex molecular mechanisms that are still being deciphered. Here, we review recent single-molecule experiments and molecular dynamics simulations that are providing novel insights into DNA mechanics from such a molecular perspective. We first discuss recent findings on sequence-dependent DNA mechanical properties, including sequences that resist mechanical stress and sequences that can accommodate strong deformations. We then comment on the intricate effects of cytosine methylation and DNA mismatches on DNA mechanics. Finally, we review recently reported differences in the mechanical properties of DNA and double-stranded RNA, the other double-helical carrier of genetic information. A thorough examination of the recent single-molecule literature permits establishing a set of general 'rules' that reasonably explain the mechanics of nucleic acids at the base pair level. These simple rules offer an improved description of certain biological systems and might serve as valuable guidelines for future design of DNA and RNA nanostructures.
Collapse
|
17
|
Schneider M, Al-Shaer A, Forde NR. AutoSmarTrace: Automated chain tracing and flexibility analysis of biological filaments. Biophys J 2021; 120:2599-2608. [PMID: 34022242 DOI: 10.1016/j.bpj.2021.05.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/12/2021] [Accepted: 05/17/2021] [Indexed: 11/19/2022] Open
Abstract
Single-molecule imaging is widely used to determine statistical distributions of molecular properties. One such characteristic is the bending flexibility of biological filaments, which can be parameterized via the persistence length. Quantitative extraction of persistence length from images of individual filaments requires both the ability to trace the backbone of the chains in the images and sufficient chain statistics to accurately assess the persistence length. Chain tracing can be a tedious task, performed manually or using algorithms that require user input and/or supervision. Such interventions have the potential to introduce user-dependent bias into the chain selection and tracing. Here, we introduce a fully automated algorithm for chain tracing and determination of persistence lengths. Dubbed "AutoSmarTrace," the algorithm is built off a neural network, trained via machine learning to identify filaments within images recorded using atomic force microscopy. We validate the performance of AutoSmarTrace on simulated images with widely varying levels of noise, demonstrating its ability to return persistence lengths in agreement with input simulation parameters. Persistence lengths returned from analysis of experimental images of collagen and DNA agree with previous values obtained from these images with different chain-tracing approaches. Although trained on atomic-force-microscopy-like images, the algorithm also shows promise to identify chains in other single-molecule imaging approaches, such as rotary-shadowing electron microscopy and fluorescence imaging.
Collapse
Affiliation(s)
- Mathew Schneider
- Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Alaa Al-Shaer
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Nancy R Forde
- Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada; Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada.
| |
Collapse
|
18
|
Basu A, Bobrovnikov DG, Ha T. DNA mechanics and its biological impact. J Mol Biol 2021; 433:166861. [PMID: 33539885 DOI: 10.1016/j.jmb.2021.166861] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 02/06/2023]
Abstract
Almost all nucleoprotein interactions and DNA manipulation events involve mechanical deformations of DNA. Extraordinary progresses in single-molecule, structural, and computational methods have characterized the average mechanical properties of DNA, such as bendability and torsional rigidity, in high resolution. Further, the advent of sequencing technology has permitted measuring, in high-throughput, how such mechanical properties vary with sequence and epigenetic modifications along genomes. We review these recent technological advancements, and discuss how they have contributed to the emerging idea that variations in the mechanical properties of DNA play a fundamental role in regulating, genome-wide, diverse processes involved in chromatin organization.
Collapse
Affiliation(s)
- Aakash Basu
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Dmitriy G Bobrovnikov
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Taekjip Ha
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Biophysics, Johns Hopkins University, Baltimore, MD 21218, USA; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Baltimore, MD 21205, USA
| |
Collapse
|
19
|
Marin-Gonzalez A, Aicart-Ramos C, Marin-Baquero M, Martín-González A, Suomalainen M, Kannan A, Vilhena JG, Greber UF, Moreno-Herrero F, Pérez R. Double-stranded RNA bending by AU-tract sequences. Nucleic Acids Res 2021; 48:12917-12928. [PMID: 33245767 PMCID: PMC7736806 DOI: 10.1093/nar/gkaa1128] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 10/08/2020] [Accepted: 11/10/2020] [Indexed: 12/16/2022] Open
Abstract
Sequence-dependent structural deformations of the DNA double helix (dsDNA) have been extensively studied, where adenine tracts (A-tracts) provide a striking example for global bending in the molecule. However, in contrast to dsDNA, sequence-dependent structural features of dsRNA have received little attention. In this work, we demonstrate that the nucleotide sequence can induce a bend in a canonical Watson-Crick base-paired dsRNA helix. Using all-atom molecular dynamics simulations, we identified a sequence motif consisting of alternating adenines and uracils, or AU-tracts, that strongly bend the RNA double-helix. This finding was experimentally validated using atomic force microscopy imaging of dsRNA molecules designed to display macroscopic curvature via repetitions of phased AU-tract motifs. At the atomic level, this novel phenomenon originates from a localized compression of the dsRNA major groove and a large propeller twist at the position of the AU-tract. Moreover, the magnitude of the bending can be modulated by changing the length of the AU-tract. Altogether, our results demonstrate the possibility of modifying the dsRNA curvature by means of its nucleotide sequence, which may be exploited in the emerging field of RNA nanotechnology and might also constitute a natural mechanism for proteins to achieve recognition of specific dsRNA sequences.
Collapse
Affiliation(s)
- Alberto Marin-Gonzalez
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Cantoblanco, Madrid, Spain
| | - Clara Aicart-Ramos
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Cantoblanco, Madrid, Spain
| | - Mikel Marin-Baquero
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Cantoblanco, Madrid, Spain
| | - Alejandro Martín-González
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Cantoblanco, Madrid, Spain
| | - Maarit Suomalainen
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Abhilash Kannan
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - J G Vilhena
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland.,Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Urs F Greber
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Fernando Moreno-Herrero
- Department of Macromolecular Structures, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, 28049 Cantoblanco, Madrid, Spain
| | - Rubén Pérez
- Departamento de Física Teórica de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain.,IFIMAC - Condensed Matter Physics Center, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| |
Collapse
|
20
|
Velasco-Berrelleza V, Burman M, Shepherd JW, Leake MC, Golestanian R, Noy A. SerraNA: a program to determine nucleic acids elasticity from simulation data. Phys Chem Chem Phys 2020; 22:19254-19266. [DOI: 10.1039/d0cp02713h] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
AT-rich motifs can generate extreme mechanical properties, which are critical for creating strong global bends when phased properly.
Collapse
Affiliation(s)
| | | | | | - Mark C. Leake
- Department of Physics
- University of York
- York
- UK
- Department of Biology
| | - Ramin Golestanian
- Max Planck Institute for Dynamics and Self-Organization (MPIDS)
- Göttingen
- Germany
- Rudolf Peierls Center for Theoretical Physics
- University of Oxford
| | - Agnes Noy
- Department of Physics
- University of York
- York
- UK
| |
Collapse
|