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Ekram MAE, Campbell M, Kose SH, Plet C, Hamilton R, Bijaksana S, Grice K, Russell J, Stevenson J, Vogel H, Coolen MJL. A 1 Ma sedimentary ancient DNA (sedaDNA) record of catchment vegetation changes and the developmental history of tropical Lake Towuti (Sulawesi, Indonesia). GEOBIOLOGY 2024; 22:e12599. [PMID: 38745401 DOI: 10.1111/gbi.12599] [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: 07/06/2023] [Revised: 12/24/2023] [Accepted: 04/18/2024] [Indexed: 05/16/2024]
Abstract
Studying past ecosystems from ancient environmental DNA preserved in lake sediments (sedaDNA) is a rapidly expanding field. This research has mainly involved Holocene sediments from lakes in cool climates, with little known about the suitability of sedaDNA to reconstruct substantially older ecosystems in the warm tropics. Here, we report the successful recovery of chloroplast trnL (UAA) sequences (trnL-P6 loop) from the sedimentary record of Lake Towuti (Sulawesi, Indonesia) to elucidate changes in regional tropical vegetation assemblages during the lake's Late Quaternary paleodepositional history. After the stringent removal of contaminants and sequence artifacts, taxonomic assignment of the remaining genuine trnL-P6 reads showed that native nitrogen-fixing legumes, C3 grasses, and shallow wetland vegetation (Alocasia) were most strongly associated with >1-million-year-old (>1 Ma) peats and silts (114-98.8 m composite depth; mcd), which were deposited in a landscape of active river channels, shallow lakes, and peat-swamps. A statistically significant shift toward partly submerged shoreline vegetation that was likely rooted in anoxic muddy soils (i.e., peatland forest trees and wetland C3 grasses (Oryzaceae) and nutrient-demanding aquatic herbs (presumably Oenanthe javanica)) occurred at 76 mcd (~0.8 Ma), ~0.2 Ma after the transition into a permanent lake. This wetland vegetation was most strongly associated with diatom ooze (46-37 mcd), thought to be deposited during maximum nutrient availability and primary productivity. Herbs (Brassicaceae), trees/shrubs (Fabaceae and Theaceae), and C3 grasses correlated with inorganic parameters, indicating increased drainage of ultramafic sediments and laterite soils from the lakes' catchment, particularly at times of inferred drying. Downcore variability in trnL-P6 from tropical forest trees (Toona), shady ground cover herbs (Zingiberaceae), and tree orchids (Luisia) most strongly correlated with sediments of a predominantly felsic signature considered to be originating from the catchment of the Loeha River draining into Lake Towuti during wetter climate conditions. However, the co-correlation with dry climate-adapted trees (i.e., Castanopsis or Lithocarpus) plus C4 grasses suggests that increased precipitation seasonality also contributed to the increased drainage of felsic Loeha River sediments. This multiproxy approach shows that despite elevated in situ temperatures, tropical lake sediments potentially comprise long-term archives of ancient environmental DNA for reconstructing ecosystems, which warrants further exploration.
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Affiliation(s)
- Md Akhtar-E Ekram
- The Institute for Geoscience Research (TIGeR), Western Australia Organic and Isotope Geochemistry Centre (WAOIGC), School of Earth and Planetary Sciences (EPS), Curtin University, Bentley, Western Australia, Australia
| | - Matthew Campbell
- The Institute for Geoscience Research (TIGeR), Western Australia Organic and Isotope Geochemistry Centre (WAOIGC), School of Earth and Planetary Sciences (EPS), Curtin University, Bentley, Western Australia, Australia
| | - Sureyya H Kose
- The Institute for Geoscience Research (TIGeR), Western Australia Organic and Isotope Geochemistry Centre (WAOIGC), School of Earth and Planetary Sciences (EPS), Curtin University, Bentley, Western Australia, Australia
| | - Chloe Plet
- The Institute for Geoscience Research (TIGeR), Western Australia Organic and Isotope Geochemistry Centre (WAOIGC), School of Earth and Planetary Sciences (EPS), Curtin University, Bentley, Western Australia, Australia
| | - Rebecca Hamilton
- ARC Centre of Excellence for Australian Biodiversity and Heritage and Archaeology and Natural History, School of Culture, History, and Language, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Satria Bijaksana
- Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, Indonesia
| | - Kliti Grice
- The Institute for Geoscience Research (TIGeR), Western Australia Organic and Isotope Geochemistry Centre (WAOIGC), School of Earth and Planetary Sciences (EPS), Curtin University, Bentley, Western Australia, Australia
| | - James Russell
- Department of Earth, Environmental, and Planetary Sciences (DEEPS), Brown University, Providence, Rhode Island, USA
| | - Janelle Stevenson
- ARC Centre of Excellence for Australian Biodiversity and Heritage and Archaeology and Natural History, School of Culture, History, and Language, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Hendrik Vogel
- Institute of Geological Sciences & Oeschger Centre for Climate Change Research, University of Bern, Bern, Switzerland
| | - Marco J L Coolen
- The Institute for Geoscience Research (TIGeR), Western Australia Organic and Isotope Geochemistry Centre (WAOIGC), School of Earth and Planetary Sciences (EPS), Curtin University, Bentley, Western Australia, Australia
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2
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Hlushko R, Pozharski E, Prabhu VM, Andrianov AK. Directly visualizing individual polyorganophosphazenes and their single-chain complexes with proteins. COMMUNICATIONS MATERIALS 2024; 5:36. [PMID: 38817739 PMCID: PMC11139433 DOI: 10.1038/s43246-024-00476-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 03/07/2024] [Indexed: 06/01/2024]
Abstract
Polyorganophosphazenes are water-soluble macromolecules with immunoadjuvant activity that self-assemble with proteins to enable biological functionality. Direct imaging by cryogenic electron microscopy uncovers the coil structure of those highly charged macromolecules. The successful visualization of individual polymer chains within the vitrified state is achieved in the absence of additives for contrast enhancement and is attributed to the high mass contrast of the inorganic backbone. Upon assembly with proteins, multiple protein copies bind at the single polymer chain level resulting in structures reminiscent of compact spherical complexes or stiffened coils. The outcome depends on protein characteristics and cannot be deduced by commonly used characterization techniques, such as light scattering, thus revealing direct morphological insights crucial for understanding biological activity. Atomic force microscopy supports the morphology outcomes while advanced analytical techniques confirm protein-polymer binding. The chain visualization methodology provides tools for gaining insights into the processes of supramolecular assembly and mechanistic aspects of polymer enabled vaccine delivery.
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Affiliation(s)
- Raman Hlushko
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland 20850, United States of America
| | - Edwin Pozharski
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland 20850, United States of America
| | - Vivek M. Prabhu
- Materials Science and Engineering Division, Material Measurement Laboratory, National Institute of Standards and Technology‡, 100 Bureau Drive, Gaithersburg, Maryland 20899, United States of America
| | - Alexander K. Andrianov
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, Maryland 20850, United States of America
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3
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Bertrand E, Demongin C, Dobra I, Rengifo-Gonzalez JC, Singatulina AS, Sukhanova MV, Lavrik OI, Pastré D, Hamon L. FUS fibrillation occurs through a nucleation-based process below the critical concentration required for liquid-liquid phase separation. Sci Rep 2023; 13:7772. [PMID: 37179431 PMCID: PMC10183042 DOI: 10.1038/s41598-023-34558-1] [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: 09/06/2022] [Accepted: 05/03/2023] [Indexed: 05/15/2023] Open
Abstract
FUS is an RNA-binding protein involved in familiar forms of ALS and FTLD that also assembles into fibrillar cytoplasmic aggregates in some neurodegenerative diseases without genetic causes. The self-adhesive prion-like domain in FUS generates reversible condensates via the liquid-liquid phase separation process (LLPS) whose maturation can lead to the formation of insoluble fibrillar aggregates in vitro, consistent with the appearance of cytoplasmic inclusions in ageing neurons. Using a single-molecule imaging approach, we reveal that FUS can assemble into nanofibrils at concentrations in the nanomolar range. These results suggest that the formation of fibrillar aggregates of FUS could occur in the cytoplasm at low concentrations of FUS, below the critical ones required to trigger the liquid-like condensate formation. Such nanofibrils may serve as seeds for the formation of pathological inclusions. Interestingly, the fibrillation of FUS at low concentrations is inhibited by its binding to mRNA or after the phosphorylation of its prion-like domain, in agreement with previous models.
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Affiliation(s)
- Emilie Bertrand
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - Clément Demongin
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - Ioana Dobra
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | | | - Anastasia S Singatulina
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
- Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia, 630090
| | - Maria V Sukhanova
- Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia, 630090
| | - Olga I Lavrik
- Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia, 630090
| | - David Pastré
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - Loic Hamon
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France.
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4
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Infrared nanospectroscopic imaging of DNA molecules on mica surface. Sci Rep 2022; 12:18972. [PMID: 36348038 PMCID: PMC9643503 DOI: 10.1038/s41598-022-23637-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
Significant efforts have been done in last two decades to develop nanoscale spectroscopy techniques owning to their great potential for single-molecule structural detection and in addition, to resolve open questions in heterogeneous biological systems, such as protein-DNA complexes. Applying IR-AFM technique has become a powerful leverage for obtaining simultaneous absorption spectra with a nanoscale spatial resolution for studied proteins, however the AFM-IR investigation of DNA molecules on surface, as a benchmark for a nucleoprotein complexes nanocharacterization, has remained elusive. Herein, we demonstrate methodological approach for acquisition of AFM-IR mapping modalities with corresponding absorption spectra based on two different DNA deposition protocols on spermidine and Ni2+ pretreated mica surface. The nanoscale IR absorbance of distinctly formed DNA morphologies on mica are demonstrated through series of AFM-IR absorption maps with corresponding IR spectrum. Our results thus demonstrate the sensitivity of AFM-IR nanospectroscopy for a nucleic acid research with an open potential to be employed in further investigation of nucleoprotein complexes.
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Complexation in Aqueous Solution of a Hydrophobic Polyanion (PSSNa) Bearing Different Charge Densities with a Hydrophilic Polycation (PDADMAC). Polymers (Basel) 2022; 14:polym14122404. [PMID: 35745980 PMCID: PMC9229680 DOI: 10.3390/polym14122404] [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: 05/14/2022] [Revised: 06/03/2022] [Accepted: 06/05/2022] [Indexed: 11/16/2022] Open
Abstract
In this work the electrostatic complexation of two strong polyelectrolytes (PEs) was studied, the hydrophilic and positively charged poly (diallyldimethylammonium chloride) (PDADMAC) and the hydrophobic and negatively charged poly (styrene-co-sodium styrene sulfonate) (P(St-co-SSNa)), which was prepared at different sulfonation rates. The latter is known to adopt a pearl necklace conformation in solution for intermediate sulfonation rates, suggesting that a fraction of the P(St-co-SSNa) charges might be trapped in these hydrophobic domains; thus making them unavailable for complexation. The set of complementary techniques (DLS, zetametry, ITC, binding experiment with a cationic and metachromatic dye) used in this work highlighted that this was not the case and that all anionic charges of P(St-co-SSNa) were in fact available for complexation either with the polycationic PDADMAC or the monocationic o-toluidine blue dye. Only minor differences were observed between these techniques, consistently showing a complexation stoichiometry close to 1:1 at the charge equivalence for the different P(St-co-SSNa) compositions. A key result emphasizing that (i) the strength of the electrostatic interaction overcomes the hydrophobic effect responsible for pearl formation, and (ii) the efficiency of complexation does not depend significantly on differences in charge density between PDADMAC and P(St-co-SSNa), highlighting that PE chains can undergo conformational rearrangements favoring the juxtaposition of segments of opposite charge. Finally, these data have shown that the formation of colloidal PECs, such as PDADMAC and P(St-co-SSNa), occurs in two distinct steps with the formation of small primary complex particles (<50 nm) by pairing of opposite charges (exothermic step) followed by their aggregation within finite-size clusters (endothermic step). This observation is in agreement with the previously described mechanism of PEC particle formation from strongly interacting systems containing a hydrophobic PE.
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Chardon F, Japaridze A, Witt H, Velikovsky L, Chakraborty C, Wilhelm T, Dumont M, Yang W, Kikuti C, Gangnard S, Mace AS, Wuite G, Dekker C, Fachinetti D. CENP-B-mediated DNA loops regulate activity and stability of human centromeres. Mol Cell 2022; 82:1751-1767.e8. [PMID: 35320753 DOI: 10.1016/j.molcel.2022.02.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 02/22/2022] [Accepted: 02/23/2022] [Indexed: 12/25/2022]
Abstract
Chromosome inheritance depends on centromeres, epigenetically specified regions of chromosomes. While conventional human centromeres are known to be built of long tandem DNA repeats, much of their architecture remains unknown. Using single-molecule techniques such as AFM, nanopores, and optical tweezers, we find that human centromeric DNA exhibits complex DNA folds such as local hairpins. Upon binding to a specific sequence within centromeric regions, the DNA-binding protein CENP-B compacts centromeres by forming pronounced DNA loops between the repeats, which favor inter-chromosomal centromere compaction and clustering. This DNA-loop-mediated organization of centromeric chromatin participates in maintaining centromere position and integrity upon microtubule pulling during mitosis. Our findings emphasize the importance of DNA topology in centromeric regulation and stability.
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Affiliation(s)
- Florian Chardon
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Aleksandre Japaridze
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands
| | - Hannes Witt
- Department of Physics and Astronomy, LaserLaB Amsterdam, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands
| | - Leonid Velikovsky
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Camellia Chakraborty
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Therese Wilhelm
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Marie Dumont
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Wayne Yang
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands
| | - Carlos Kikuti
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Stephane Gangnard
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Anne-Sophie Mace
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France
| | - Gijs Wuite
- Department of Physics and Astronomy, LaserLaB Amsterdam, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands
| | - Cees Dekker
- Department of Bionanoscience, Kavli Institute of Nanoscience Delft, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands
| | - Daniele Fachinetti
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, 75005 Paris, France.
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7
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Arumughan V, Nypelö T, Hasani M, Larsson A. Calcium Ion-Induced Structural Changes in Carboxymethylcellulose Solutions and Their Effects on Adsorption on Cellulose Surfaces. Biomacromolecules 2021; 23:47-56. [PMID: 34936336 PMCID: PMC8753602 DOI: 10.1021/acs.biomac.1c00895] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The adsorption of
carboxymethylcellulose (CMC) on cellulose surfaces
is one of the most studied examples of the adsorption of an anionic
polyelectrolyte on a like-charged surface. It has been suggested that
divalent ions can act as a bridge between CMC chains and the surface
of cellulose and enhance the CMC adsorption: they can, however, also
alter the structure of CMCs in the solution. In previous investigations,
the influence of cations on solution properties has been largely overlooked.
This study investigates the effect of Ca2+ ions on the
properties of CMC solutions as well as the influence on cellulose
nanofibers (CNFs), which was studied by dynamic light scattering and
correlated with the adsorption of CMC on a cellulose surface probed
using QCM-D. The presence of Ca2+ facilitated the multichain
association of CMC chains and increased the hydrodynamic diameter.
This suggests that the adsorption of CMCs at high concentrations of
CaCl2 is governed mainly by changes in solution properties
rather than by changes in the cellulose surface. Furthermore, an entropy-driven
mechanism has been suggested for the adsorption of CMC on cellulose.
By comparing the adsorption of CMC from H2O and D2O, it was found that the release of water from the cellulose surface
is driving the adsorption of CMC.
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Affiliation(s)
- Vishnu Arumughan
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,AvanCell, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Tiina Nypelö
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,Wallenberg Wood Science Center, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Merima Hasani
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,AvanCell, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,Wallenberg Wood Science Center, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Anette Larsson
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,AvanCell, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,Wallenberg Wood Science Center, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden.,FibRe─Centre for Lignocellulose-based Thermoplastics, Department of Chemistry and Chemical Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
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8
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Arumughan V, Nypelö T, Hasani M, Larsson A. Fundamental aspects of the non-covalent modification of cellulose via polymer adsorption. Adv Colloid Interface Sci 2021; 298:102529. [PMID: 34773888 DOI: 10.1016/j.cis.2021.102529] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 09/24/2021] [Accepted: 09/25/2021] [Indexed: 12/13/2022]
Abstract
The increasing need for new material applications based on cellulose demands increased functional diversity and thus new functionalisation/modification approaches. The non-covalent modification of cellulose fibres via the adsorption of functional polymers has emerged as a promising route for tailoring the properties of material. This review focuses on fundamental aspects of polymer adsorption on cellulose surfaces, where the adsorption of polyelectrolytes and non-polyelectrolytes are treated separately. Adsorption studies on model surfaces as well as cellulose macro-fibres are reviewed. A correlation of the adsorption findings with the Scheutjens-Fleer polymer adsorption theory is provided, allowing the fundamentals behind the polymer adsorption phenomenon and its context in utilization of cellulose fibres to be understood.
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9
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Revealing DNA Structure at Liquid/Solid Interfaces by AFM-Based High-Resolution Imaging and Molecular Spectroscopy. Molecules 2021; 26:molecules26216476. [PMID: 34770895 PMCID: PMC8587808 DOI: 10.3390/molecules26216476] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/22/2021] [Accepted: 10/25/2021] [Indexed: 11/24/2022] Open
Abstract
DNA covers the genetic information in all living organisms. Numerous intrinsic and extrinsic factors may influence the local structure of the DNA molecule or compromise its integrity. Detailed understanding of structural modifications of DNA resulting from interactions with other molecules and surrounding environment is of central importance for the future development of medicine and pharmacology. In this paper, we review the recent achievements in research on DNA structure at nanoscale. In particular, we focused on the molecular structure of DNA revealed by high-resolution AFM (Atomic Force Microscopy) imaging at liquid/solid interfaces. Such detailed structural studies were driven by the technical developments made in SPM (Scanning Probe Microscopy) techniques. Therefore, we describe here the working principles of AFM modes allowing high-resolution visualization of DNA structure under native (liquid) environment. While AFM provides well-resolved structure of molecules at nanoscale, it does not reveal the chemical structure and composition of studied samples. The simultaneous information combining the structural and chemical details of studied analyte allows achieve a comprehensive picture of investigated phenomenon. Therefore, we also summarize recent molecular spectroscopy studies, including Tip-Enhanced Raman Spectroscopy (TERS), on the DNA structure and its structural rearrangements.
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10
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Yang S, Liu W, Zhang Y, Wang R. Bottom-Up Fabrication of Large-Scale Gold Nanorod Arrays by Surface Diffusion-Mediated DNA Origami Assembly. ACS APPLIED MATERIALS & INTERFACES 2021; 13:50516-50523. [PMID: 34637259 DOI: 10.1021/acsami.1c13173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Self-assembly of anisotropic metal nanoparticles serves as an effective bottom-up route for the nanofabrication of novel artifacts. However, there still are many challenges to rationally manipulate anisotropic particles due to the size and geometric restrictions. To avoid the aggregation and mishybridization from DNA sticky-end-guided assembly in buffer solution, in this work, we utilized a cation-controlled surface diffusion strategy to the spatial arrangement of gold nanorods (AuNRs) into 1D and 2D arrays by using DNA origami tiles as binding frames on the solid-liquid interface through π-π stacking interactions. To facilitate the further manipulation of those patterns, a novel pattern transfer method was introduced to transfer the arrays of AuNRs from a liquid to a dry ambient environment with high yield and minor structural damage. The results demonstrated a successful strategy of DNA origami-assisted, large-scale assembly of AuNRs for constructing complex superstructures with potential applications in the nanofabrication of plasmonic and electronic devices.
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Affiliation(s)
- Shuo Yang
- Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| | - Wenyan Liu
- Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
- Center for Research in Energy and Environment, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| | - Yuwei Zhang
- Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| | - Risheng Wang
- Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
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11
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Matsarskaia O, Roosen‐Runge F, Schreiber F. Multivalent ions and biomolecules: Attempting a comprehensive perspective. Chemphyschem 2020; 21:1742-1767. [PMID: 32406605 PMCID: PMC7496725 DOI: 10.1002/cphc.202000162] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 05/13/2020] [Indexed: 12/13/2022]
Abstract
Ions are ubiquitous in nature. They play a key role for many biological processes on the molecular scale, from molecular interactions, to mechanical properties, to folding, to self-organisation and assembly, to reaction equilibria, to signalling, to energy and material transport, to recognition etc. Going beyond monovalent ions to multivalent ions, the effects of the ions are frequently not only stronger (due to the obviously higher charge), but qualitatively different. A typical example is the process of binding of multivalent ions, such as Ca2+ , to a macromolecule and the consequences of this ion binding such as compaction, collapse, potential charge inversion and precipitation of the macromolecule. Here we review these effects and phenomena induced by multivalent ions for biological (macro)molecules, from the "atomistic/molecular" local picture of (potentially specific) interactions to the more global picture of phase behaviour including, e. g., crystallisation, phase separation, oligomerisation etc. Rather than attempting an encyclopedic list of systems, we rather aim for an embracing discussion using typical case studies. We try to cover predominantly three main classes: proteins, nucleic acids, and amphiphilic molecules including interface effects. We do not cover in detail, but make some comparisons to, ion channels, colloidal systems, and synthetic polymers. While there are obvious differences in the behaviour of, and the relevance of multivalent ions for, the three main classes of systems, we also point out analogies. Our attempt of a comprehensive discussion is guided by the idea that there are not only important differences and specific phenomena with regard to the effects of multivalent ions on the main systems, but also important similarities. We hope to bridge physico-chemical mechanisms, concepts of soft matter, and biological observations and connect the different communities further.
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Affiliation(s)
| | - Felix Roosen‐Runge
- Department of Biomedical Sciences and Biofilms-Research Center for Biointerfaces (BRCB), Faculty of Health and SocietyMalmö UniversitySweden
- Division of Physical ChemistryLund UniversitySweden
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12
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Andrade H, Thomas AK, Lin W, Reddavide FV, Zhang Y. Using a PCR-Based Method To Analyze and Model Large, Heterogeneous Populations of DNA. Chembiochem 2020; 21:1144-1149. [PMID: 31674719 PMCID: PMC7217214 DOI: 10.1002/cbic.201900603] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Indexed: 01/03/2023]
Abstract
The study of populations of large size and high diversity is limited by the capability of collecting data. Moreover, for a pool of individuals, each associated with a unique characteristic feature, as the pool size grows, the possible interactions increase exponentially and quickly go beyond the limit of computation and experimental studies. Herein, the design of DNA libraries with various diversity is reported. By using a facile analytical method based on real‐time PCR, the diversity of a pool of DNA can be evaluated to allow extraordinarily high heterogenicity (e.g., >1 trillion). It is demonstrated that these DNA libraries can be used to model heterogeneous populations; these libraries exhibit functions such as self‐protection, suitability for biased expansion, and the possibility to evolve into amorphous structures. The method has shown the remarkable power of parallel computing with DNA, since it can resemble an analogue computer and be applied in selection‐based biotechnology methods, such as DNA‐encoded chemical libraries. As a chemical approach to solve problems traditionally for genetic and statistical analysis, the method provides a quick and cost‐efficient evaluation of library diversity for intermediate steps through a selection process.
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Affiliation(s)
- Helena Andrade
- B CUBE Center for Molecular Bioengineering, Technische Universität Dresden, Tatzberg 41, 01307, Dresden, Germany
| | - Alvin K Thomas
- B CUBE Center for Molecular Bioengineering, Technische Universität Dresden, Tatzberg 41, 01307, Dresden, Germany
| | - Weilin Lin
- B CUBE Center for Molecular Bioengineering, Technische Universität Dresden, Tatzberg 41, 01307, Dresden, Germany
| | | | - Yixin Zhang
- B CUBE Center for Molecular Bioengineering, Technische Universität Dresden, Tatzberg 41, 01307, Dresden, Germany
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13
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Abstract
Atomic force and transmission electron microscopies (AFM/TEM) are powerful tools to analyze RNA-based nanostructures. While cryo-TEM analysis allows the determination of near-atomic resolution structures of large RNA complexes, this chapter intends to present how RNA nanostructures can be analyzed at room temperature on surfaces. Indeed, TEM and AFM analyses permit the conformation of a large population of individual molecular structures to be observed, providing a statistical basis for the variability of these nanostructures within the population. Nevertheless, if double-stranded DNA molecular imaging has been described extensively, only a few investigations of single-stranded DNA and RNA filaments have been conducted so far. Indeed, technique for spreading and adsorption of ss-molecules on AFM surfaces or TEM grids is a crucial step to avoid disturbing RNA conformation on the surface. In this chapter, we present a specific method to analyze RNA assemblies and RNA-protein complexes for molecular microscopies.
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Affiliation(s)
- Olivier Piétrement
- Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS, Université de Bourgogne, Dijon Cedex, France
| | - Véronique Arluison
- Laboratoire Léon Brillouin LLB, CEA, CNRS UMR12, Université Paris Saclay, Gif-Sur-Yvette, France
- Université de Paris, Paris, France
| | - Christophe Lavelle
- Museum National d'Histoire Naturelle, CNRS UMR 7196/INSERM U1154, Paris, France.
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14
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Recombinases and Related Proteins in the Context of Homologous Recombination Analyzed by Molecular Microscopy. Methods Mol Biol 2019; 1805:251-270. [PMID: 29971722 DOI: 10.1007/978-1-4939-8556-2_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
Transmission electron microscopy (TEM) and atomic force microscopy (AFM) are powerful tools to study the behavior of various actors in homologous recombination including molecular motors such as recombinases and helicases/translocases. Here we present specific approaches developed in terms of sample preparation and imaging methods to contribute to the understanding of homologous recombination process and its regulation focusing on the interplay between recombinases and other related proteins such as mediators or antirecombinase actors.Homologous recombination (HR) is a high-fidelity DNA repair pathway since it uses a homologous DNA as template. Recombinases such as RecA in bacteria, RadA in archaea, and Rad51 in eukaryotes are key proteins in the HR pathway: HR is initiated with formation of an ssDNA overhang on which recombinases polymerize and form a dynamic active nucleoprotein filament able to search for homology and to exchange DNA strand in an ATP-dependent manner. We provide practical methods to analyze presynaptic filament formation on ssDNA, its composition and regulation in presence of mediator partners, antirecombinase activity of translocase, and chromatin remodeling events.
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15
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Abstract
The predictable nature of DNA interactions enables the programmable assembly of highly advanced 2D and 3D DNA structures of nanoscale dimensions. The access to ever larger and more complex structures has been achieved through decades of work on developing structural design principles. Concurrently, an increased focus has emerged on the applications of DNA nanostructures. In its nature, DNA is chemically inert and nanostructures based on unmodified DNA mostly lack function. However, functionality can be obtained through chemical modification of DNA nanostructures and the opportunities are endless. In this review, we discuss methodology for chemical functionalization of DNA nanostructures and provide examples of how this is being used to create functional nanodevices and make DNA nanostructures more applicable. We aim to encourage researchers to adopt chemical modifications as part of their work in DNA nanotechnology and inspire chemists to address current challenges and opportunities within the field.
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Affiliation(s)
- Mikael Madsen
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry , Aarhus University , Gustav Wieds Vej 14 , DK - 8000 Aarhus C, Denmark
| | - Kurt V Gothelf
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry , Aarhus University , Gustav Wieds Vej 14 , DK - 8000 Aarhus C, Denmark
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16
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Atomic force microscopy study of EDTA induced desorption of metal ions immobilized DNA from mica surface. Ultramicroscopy 2019; 199:7-15. [PMID: 30711717 DOI: 10.1016/j.ultramic.2019.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 01/26/2019] [Indexed: 01/25/2023]
Abstract
Adsorption of DNA molecules onto substrate, such as mica, is well documented. However, desorption of the immobilized DNA molecules from substrate, which is also an important aspect of DNA behavior on substrate, has not been paid much attention. Here, DNA molecules were first immobilized on mica surface by using divalent metal ions as the bridge agents. Desorption of the immobilized DNA from mica surface was realized via ethylenediamine tetraacetic acid disodium salt (EDTA) treatment. EDTA is a chelating agent; it can remove the bridging metal ions between DNA and mica, which leads to the release of DNA molecules from mica substrate. The divalent metal ions assisted DNA adsorption onto mica surface and the EDTA induced DNA desorption from mica surface were followed by atomic force microscopy (AFM). Randomly dispersed DNA strands and DNA networks are two distinct adsorption morphologies of DNA on mica surface and their desorption processes from mica surface induced by EDTA are also different. Other factors that influence the EDTA-induced DNA desorption, such as type of bridging metal ion and DNA molecule length, have also been systematically studied. Moreover, EDTA treatment has no effect on the integrity of DNA molecule. The EDTA induced desorption of metal ions immobilized DNA from mica surface is simple and effective, which has potential applications in DNA separation and purification, DNA biophysics, and DNA-based nanotechnology.
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17
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Pisano S, Gilson E. Analysis of DNA-Protein Complexes by Atomic Force Microscopy Imaging: The Case of TRF2-Telomeric DNA Wrapping. Methods Mol Biol 2019; 1886:75-97. [PMID: 30374863 DOI: 10.1007/978-1-4939-8894-5_5] [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] [Indexed: 06/08/2023]
Abstract
Atomic force microscopy (AFM) is a non-optical microscopy that enables the acquisition at the nanoscale level of a 3D topographical image of the sample. For 30 years, AFM has been a valuable tool in life sciences to study biological samples in the field of tissue, cellular and molecular imaging, of mechanical properties and of force spectroscopy. Since the early beginnings of the technique, AFM has been extensively exploited as an imaging tool for structural studies of nucleic acids and nucleoprotein complexes. The morphometric analysis performed on the images can unveil specific structural and functional aspects of the sample, such as the multimerization state of proteins bound to DNA, or DNA conformational changes led by the DNA-binding proteins. Herein, a method for analyzing a complex formed by a telomeric DNA sequence wrapped around the TRF2 binding protein is presented. The described procedure could be applied to the study of any type of DNA-protein complex.
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Affiliation(s)
- Sabrina Pisano
- Université Côte d'Azur, CNRS UMR 7284/INSERM U108, Institute for Research on Cancer and Aging, Nice (IRCAN), Medical School, Nice, France.
| | - Eric Gilson
- Université Côte d'Azur, CNRS UMR 7284/INSERM U108, Institute for Research on Cancer and Aging, Nice (IRCAN), Medical School, Nice, France
- International Laboratory in Hematology and Cancer, Pôle Sino-Français de Recherche en Sciences du Vivant et Génomique, Shanghai Ruijin Hospital, Shanghai Jiao Tong University School of Medicine/Ruijin Hospital/CNRS/INSERM/Nice University, Shanghai, China
- Department of Genetics, CHU Nice, Université Côte d'Azur, Nice, France
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18
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Brassat K, Ramakrishnan S, Bürger J, Hanke M, Doostdar M, Lindner JKN, Grundmeier G, Keller A. On the Adsorption of DNA Origami Nanostructures in Nanohole Arrays. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:14757-14765. [PMID: 29754490 DOI: 10.1021/acs.langmuir.8b00793] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
DNA origami nanostructures are versatile substrates for the controlled arrangement of molecular capture sites with nanometer precision and thus have many promising applications in single-molecule bioanalysis. Here, we investigate the adsorption of DNA origami nanostructures in nanohole arrays which represent an important class of biosensors and may benefit from the incorporation of DNA origami-based molecular probes. Nanoholes with well-defined diameter that enable the adsorption of single DNA origami triangles are fabricated in Au films on Si wafers by nanosphere lithography. The efficiency of directed DNA origami adsorption on the exposed SiO2 areas at the bottoms of the nanoholes is evaluated in dependence of various parameters, i.e., Mg2+ and DNA origami concentrations, buffer strength, adsorption time, and nanohole diameter. We observe that the buffer strength has a surprisingly strong effect on DNA origami adsorption in the nanoholes and that multiple DNA origami triangles with 120 nm edge length can adsorb in nanoholes as small as 120 nm in diameter. We attribute the latter observation to the low lateral mobility of once adsorbed DNA origami on the SiO2 surface, in combination with parasitic adsorption to the Au film. Although parasitic adsorption can be suppressed by modifying the Au film with a hydrophobic self-assembled monolayer, the limited surface mobility of the adsorbed DNA origami still leads to poor localization accuracy in the nanoholes and results in many DNA origami crossing the boundary to the Au film even under optimized conditions. We discuss possible ways to minimize this effect by varying the composition of the adsorption buffer, employing different fabrication conditions, or using other substrate materials for nanohole array fabrication.
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Piétrement O, Castro-Smirnov FA, Le Cam E, Aranda P, Ruiz-Hitzky E, Lopez BS. Sepiolite as a New Nanocarrier for DNA Transfer into Mammalian Cells: Proof of Concept, Issues and Perspectives. CHEM REC 2017; 18:849-857. [DOI: 10.1002/tcr.201700078] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 12/07/2017] [Indexed: 01/05/2023]
Affiliation(s)
- Olivier Piétrement
- CNRS UMR 8126; Université Paris-Sud, Université Paris-Saclay; Gustave Roussy, 114 Rue Edouard Vaillant 94805 Villejuif France
| | - Fidel Antonio Castro-Smirnov
- CNRS UMR 8200, team labeled “Ligue 2014”; Université Paris-Sud, Université Paris-Saclay; Gustave Roussy, 114 rue Edouard Vaillant 94805 Villejuif France
- Universidad de las Ciencias Informáticas; Carretera a San Antonio de los Baños, km 2 1/2 La Habana 19370 Cuba
| | - Eric Le Cam
- CNRS UMR 8126; Université Paris-Sud, Université Paris-Saclay; Gustave Roussy, 114 Rue Edouard Vaillant 94805 Villejuif France
| | - Pilar Aranda
- Instituto de Ciencia de Materiales de Madrid, CSIC; c/ Sor Juana Inés de la Cruz 3 28049 Madrid Spain
| | - Eduardo Ruiz-Hitzky
- Instituto de Ciencia de Materiales de Madrid, CSIC; c/ Sor Juana Inés de la Cruz 3 28049 Madrid Spain
| | - Bernard S. Lopez
- CNRS UMR 8200, team labeled “Ligue 2014”; Université Paris-Sud, Université Paris-Saclay; Gustave Roussy, 114 rue Edouard Vaillant 94805 Villejuif France
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20
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Dubrovin EV, Schächtele M, Klinov DV, Schäffer TE. Time-Lapse Single-Biomolecule Atomic Force Microscopy Investigation on Modified Graphite in Solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:10027-10034. [PMID: 28850785 DOI: 10.1021/acs.langmuir.7b02220] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Atomic force microscopy (AFM) of biomolecular processes at the single-molecule level can provide unique information for understanding molecular function. In AFM studies of biomolecular processes in solution, mica surfaces are predominantly used as substrates. However, owing to its high surface charge, mica may induce high local ionic strength in the vicinity of its surface, which may shift the equilibrium of studied biomolecular processes such as biopolymer adsorption or protein-DNA interaction. In the search for alternative substrates, we have investigated the behavior of adsorbed biomolecules, such as plasmid DNA and E. coli RNA polymerase σ70 subunit holoenzyme (RNAP), on highly oriented pyrolytic graphite (HOPG) surfaces modified with stearylamine and oligoglycine-hydrocarbon derivative (GM) monolayers using AFM in solution. We have demonstrated ionic-strength-dependent DNA mobility on GM HOPG and nativelike dimensions of RNAP molecules adsorbed on modified HOPG surfaces. We propose an approach to the real-time AFM investigation of transcription on stearylamine monolayers on graphite. We conclude that modified graphite allows us to study biomolecules and biomolecular processes on its surface at controlled ionic strength and may be used as a complement to mica in AFM investigations.
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Affiliation(s)
- Evgeniy V Dubrovin
- University of Tübingen , Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
- Federal Research and Clinical Center of Physical-Chemical Medicine , Malaya Pirogovskaya 1a, Moscow 119435, Russian Federation
- Lomonosov Moscow State University , Leninskie gory 1-2, Moscow 119991, Russian Federation
| | - Marc Schächtele
- University of Tübingen , Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
| | - Dmitry V Klinov
- Federal Research and Clinical Center of Physical-Chemical Medicine , Malaya Pirogovskaya 1a, Moscow 119435, Russian Federation
| | - Tilman E Schäffer
- University of Tübingen , Institute of Applied Physics, Auf der Morgenstelle 10, 72076 Tübingen, Germany
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21
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Jiang S, Hong F, Hu H, Yan H, Liu Y. Understanding the Elementary Steps in DNA Tile-Based Self-Assembly. ACS NANO 2017; 11:9370-9381. [PMID: 28813590 DOI: 10.1021/acsnano.7b04845] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Although many models have been developed to guide the design and implementation of DNA tile-based self-assembly systems with increasing complexity, the fundamental assumptions of the models have not been thoroughly tested. To expand the quantitative understanding of DNA tile-based self-assembly and to test the fundamental assumptions of self-assembly models, we investigated DNA tile attachment to preformed "multi-tile" arrays in real time and obtained the thermodynamic and kinetic parameters of single tile attachment in various sticky end association scenarios. With more sticky ends, tile attachment becomes more thermostable with an approximately linear decrease in the free energy change (more negative). The total binding free energy of sticky ends is partially compromised by a sequence-independent energy penalty when tile attachment forms a constrained configuration: "loop". The minimal loop is a 2 × 2 tetramer (Loop4). The energy penalty of loops of 4, 6, and 8 tiles was analyzed with the independent loop model assuming no interloop tension, which is generalizable to arbitrary tile configurations. More sticky ends also contribute to a faster on-rate under isothermal conditions when nucleation is the rate-limiting step. Incorrect sticky end contributes to neither the thermostability nor the kinetics. The thermodynamic and kinetic parameters of DNA tile attachment elucidated here will contribute to the future improvement and optimization of tile assembly modeling, precise control of experimental conditions, and structural design for error-free self-assembly.
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Affiliation(s)
- Shuoxing Jiang
- Center for Molecular Design and Biomimetics at the Biodesign Institute, and School of Molecular Sciences, Arizona State University , Tempe, Arizona 85287, United States
| | - Fan Hong
- Center for Molecular Design and Biomimetics at the Biodesign Institute, and School of Molecular Sciences, Arizona State University , Tempe, Arizona 85287, United States
| | - Huiyu Hu
- Center for Molecular Design and Biomimetics at the Biodesign Institute, and School of Molecular Sciences, Arizona State University , Tempe, Arizona 85287, United States
| | - Hao Yan
- Center for Molecular Design and Biomimetics at the Biodesign Institute, and School of Molecular Sciences, Arizona State University , Tempe, Arizona 85287, United States
| | - Yan Liu
- Center for Molecular Design and Biomimetics at the Biodesign Institute, and School of Molecular Sciences, Arizona State University , Tempe, Arizona 85287, United States
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22
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Effect of heparin and heparan sulphate on open promoter complex formation for a simple tandem gene model using ex situ atomic force microscopy. Methods 2017; 120:91-102. [DOI: 10.1016/j.ymeth.2017.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/10/2017] [Accepted: 04/14/2017] [Indexed: 11/23/2022] Open
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23
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Physical interactions between DNA and sepiolite nanofibers, and potential application for DNA transfer into mammalian cells. Sci Rep 2016; 6:36341. [PMID: 27808269 PMCID: PMC5093858 DOI: 10.1038/srep36341] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 10/10/2016] [Indexed: 11/15/2022] Open
Abstract
Nanofibers of sepiolite, a natural silicate belonging to the clay minerals family, might constitute a potential promising nanocarrier for the non-viral transfer of bio-molecules. We show here that sepiolite nanofibers efficiently bind different types of DNA molecules through electrostatic interactions, hydrogen bonding, cation bridges, and van der Waals forces. Moreover, Fourier-transform infrared spectroscopy identified the external silanol groups as the main sites of interaction with the DNA. Furthermore, as a proof of concept, we show that sepiolite is able to stably transfer plasmid DNA into mammalian cells and that the efficiency can be optimized. Indeed, sonication of sepiolite 100-fold stimulated DNA transfection efficiency. These results open the way to the use of sepiolite-based biohybrids as a novel class of nanoplatform for gene transfer with potential clinical applications.
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24
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αTAT1 controls longitudinal spreading of acetylation marks from open microtubules extremities. Sci Rep 2016; 6:35624. [PMID: 27752143 PMCID: PMC5067677 DOI: 10.1038/srep35624] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 09/27/2016] [Indexed: 01/23/2023] Open
Abstract
Acetylation of the lysine 40 of α-tubulin (K40) is a post-translational modification occurring in the lumen of microtubules (MTs) and is controlled by the α-tubulin acetyl-transferase αTAT1. How αTAT1 accesses the lumen and acetylates α-tubulin there has been an open question. Here, we report that acetylation starts at open ends of MTs and progressively spreads longitudinally from there. We observed acetylation marks at the open ends of in vivo MTs re-growing after a Nocodazole block, and acetylated segments growing in length with time. Bias for MTs extremities was even more pronounced when using non-dynamic MTs extracted from HeLa cells. In contrast, K40 acetylation was mostly uniform along the length of MTs reconstituted from purified tubulin in vitro. Quantitative modelling of luminal diffusion of αTAT1 suggested that the uniform acetylation pattern observed in vitro is consistent with defects in the MT lattice providing lateral access to the lumen. Indeed, we observed that in vitro MTs are permeable to macromolecules along their shaft while cellular MTs are not. Our results demonstrate αTAT1 enters the lumen from open extremities and spreads K40 acetylation marks longitudinally along cellular MTs. This mode of tip-directed microtubule acetylation may allow for selective acetylation of subsets of microtubules.
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25
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McMicken B, Thomas RJ, Brancaleon L. Partial Unfolding of Tubulin Heterodimers Induced by Two-Photon Excitation of Bound meso-Tetrakis(sulfonatophenyl)porphyrin. J Phys Chem B 2016; 120:3653-65. [PMID: 27035156 DOI: 10.1021/acs.jpcb.6b02055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The water-soluble porphyrin meso-tetrakis(p-sulfonatophenyl)porphyrin (TSPP) can be noncovalently bound to tubulin and used as a photosensitizer, which upon irradiation triggers photochemical reactions that lead to conformational changes of the protein. These conformational changes in turn inhibit tubulin's primary function of polymerizing into microtubules. We explored the possibility of using two-photon excitation of the bound porphyrin to induce photosensitized protein unfolding. Although TSPP has a relatively low cross section (∼30 GM) our results did find that two-photon excitation of the ligand causes partial unfolding of the tubulin host and the inhibition of the in vitro formation of microtubules. Conversely, irradiating tubulin alone caused no such effects despite the large irradiance per pulse (97-190 GW/cm(2)). The conformational changes were characterized using spectroscopic studies and provide a promising protocol for the future application of non-native photosensitization of proteins.
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Affiliation(s)
- Brady McMicken
- The University of Texas at San Antonio , Department of Physics and Astronomy, One UTSA Circle, San Antonio, Texas 78249, United States.,Human Effectiveness Directorate, Bioeffects Division, Optical Radiation Bioeffects Branch, 711th Human Performance Wing, Joint Base San Antonio , JBSA Fort Sam Houston, Texas 78234, United States
| | - Robert J Thomas
- Human Effectiveness Directorate, Bioeffects Division, Optical Radiation Bioeffects Branch, 711th Human Performance Wing, Joint Base San Antonio , JBSA Fort Sam Houston, Texas 78234, United States
| | - Lorenzo Brancaleon
- The University of Texas at San Antonio , Department of Physics and Astronomy, One UTSA Circle, San Antonio, Texas 78249, United States
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26
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Nucleic Acid Binding by Mason-Pfizer Monkey Virus CA Promotes Virus Assembly and Genome Packaging. J Virol 2016; 90:4593-4603. [PMID: 26912613 DOI: 10.1128/jvi.03197-15] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 02/15/2016] [Indexed: 12/13/2022] Open
Abstract
UNLABELLED The Gag polyprotein of retroviruses drives immature virus assembly by forming hexameric protein lattices. The assembly is primarily mediated by protein-protein interactions between capsid (CA) domains and by interactions between nucleocapsid (NC) domains and RNA. Specific interactions between NC and the viral RNA are required for genome packaging. Previously reported cryoelectron microscopy analysis of immature Mason-Pfizer monkey virus (M-PMV) particles suggested that a basic region (residues RKK) in CA may serve as an additional binding site for nucleic acids. Here, we have introduced mutations into the RKK region in both bacterial and proviral M-PMV vectors and have assessed their impact on M-PMV assembly, structure, RNA binding, budding/release, nuclear trafficking, and infectivity using in vitro and in vivo systems. Our data indicate that the RKK region binds and structures nucleic acid that serves to promote virus particle assembly in the cytoplasm. Moreover, the RKK region appears to be important for recruitment of viral genomic RNA into Gag particles, and this function could be linked to changes in nuclear trafficking. Together these observations suggest that in M-PMV, direct interactions between CA and nucleic acid play important functions in the late stages of the viral life cycle. IMPORTANCE Assembly of retrovirus particles is driven by the Gag polyprotein, which can self-assemble to form virus particles and interact with RNA to recruit the viral genome into the particles. Generally, the capsid domains of Gag contribute to essential protein-protein interactions during assembly, while the nucleocapsid domain interacts with RNA. The interactions between the nucleocapsid domain and RNA are important both for identifying the genome and for self-assembly of Gag molecules. Here, we show that a region of basic residues in the capsid protein of the betaretrovirus Mason-Pfizer monkey virus (M-PMV) contributes to interaction of Gag with nucleic acid. This interaction appears to provide a critical scaffolding function that promotes assembly of virus particles in the cytoplasm. It is also crucial for packaging the viral genome and thus for infectivity. These data indicate that, surprisingly, interactions between the capsid domain and RNA play an important role in the assembly of M-PMV.
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27
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Sukhanova MV, Abrakhi S, Joshi V, Pastre D, Kutuzov MM, Anarbaev RO, Curmi PA, Hamon L, Lavrik OI. Single molecule detection of PARP1 and PARP2 interaction with DNA strand breaks and their poly(ADP-ribosyl)ation using high-resolution AFM imaging. Nucleic Acids Res 2015; 44:e60. [PMID: 26673720 PMCID: PMC4824093 DOI: 10.1093/nar/gkv1476] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 12/05/2015] [Indexed: 12/31/2022] Open
Abstract
PARP1 and PARP2 are implicated in the synthesis of poly(ADP-ribose) (PAR) after detection of DNA damage. The specificity of PARP1 and PARP2 interaction with long DNA fragments containing single- and/or double-strand breaks (SSBs and DSBs) have been studied using atomic force microscopy (AFM) imaging in combination with biochemical approaches. Our data show that PARP1 localizes mainly on DNA breaks and exhibits a slight preference for nicks over DSBs, although the protein has a moderately high affinity for undamaged DNA. In contrast to PARP1, PARP2 is mainly detected at a single DNA nick site, exhibiting a low level of binding to undamaged DNA and DSBs. The enhancement of binding affinity of PARP2 for DNA containing a single nick was also observed using fluorescence titration. AFM studies reveal that activation of both PARPs leads to the synthesis of highly branched PAR whose size depends strongly on the presence of SSBs and DSBs for PARP1 and of SSBs for PARP2. The initial affinity between the PARP1, PARP2 and the DNA damaged site appears to influence both the size of the PAR synthesized and the time of residence of PARylated PARP1 and PARP2 on DNA damages.
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Affiliation(s)
- Maria V Sukhanova
- Institute of Chemical Biology and Fundamental Medicine, 630090, Novosibirsk, Russian Federation INSERM, U1204, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université d'Evry-Val-d'Essonne, F-91025 Evry, France
| | - Sanae Abrakhi
- INSERM, U1204, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université d'Evry-Val-d'Essonne, F-91025 Evry, France
| | - Vandana Joshi
- INSERM, U1204, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université d'Evry-Val-d'Essonne, F-91025 Evry, France
| | - David Pastre
- INSERM, U1204, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université d'Evry-Val-d'Essonne, F-91025 Evry, France
| | - Mikhail M Kutuzov
- Institute of Chemical Biology and Fundamental Medicine, 630090, Novosibirsk, Russian Federation
| | - Rashid O Anarbaev
- Institute of Chemical Biology and Fundamental Medicine, 630090, Novosibirsk, Russian Federation Novosibirsk State University, 630090, Novosibirsk, Russian Federation
| | - Patrick A Curmi
- INSERM, U1204, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université d'Evry-Val-d'Essonne, F-91025 Evry, France
| | - Loic Hamon
- INSERM, U1204, Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, Université d'Evry-Val-d'Essonne, F-91025 Evry, France
| | - Olga I Lavrik
- Institute of Chemical Biology and Fundamental Medicine, 630090, Novosibirsk, Russian Federation Novosibirsk State University, 630090, Novosibirsk, Russian Federation
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28
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Tiraferri A, Maroni P, Borkovec M. Adsorption of polyelectrolytes to like-charged substrates induced by multivalent counterions as exemplified by poly(styrene sulfonate) and silica. Phys Chem Chem Phys 2015; 17:10348-52. [PMID: 25820795 DOI: 10.1039/c5cp00910c] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The present study demonstrates that multivalent counterions trigger adsorption of polyelectrolytes on a like-charged substrate. In particular, adsorption of polystyrene sulfonate on silica is studied experimentally in NaCl, MgCl2, and LaCl3 solutions by optical reflectivity. While adsorption is negligible in the presence of Na(+), the polyelectrolyte adsorbs in the presence of Mg(2+) and La(3+). The adsorbed amount of the polyelectrolyte goes through a maximum as a function of the salt concentration. This maximum increases with increasing valence and shifts to lower salt concentrations. At low salt concentration, the adsorption is negligible. At intermediate salt level, ripening and multilayer formation leads to continuous growth of the adsorbed layer. At higher salt level, blocking and formation of a monolayer lead to saturation. These results are tentatively interpreted in terms of a charge reversal of the polyelectrolyte-metal complex. The molecular mass of the polyelectrolyte has an important effect on the adsorption behavior, whereby the tendency towards ripening becomes more pronounced at large molecular mass.
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Affiliation(s)
- Alberto Tiraferri
- Department of Environment, Land, and Infrastructure Engineering, Polytechnic University of Turin, Torino, Italy
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29
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Pillers MA, Shute R, Farchone A, Linder KP, Doerfler R, Gavin C, Goss V, Lieberman M. Preparation of Mica and Silicon Substrates for DNA Origami Analysis and Experimentation. J Vis Exp 2015:e52972. [PMID: 26274888 PMCID: PMC4545022 DOI: 10.3791/52972] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of these applications require interaction with and adhesion of DNA nanostructures to a substrate. Due to its atomically flat and easily cleaned nature, mica has been the substrate of choice for DNA origami experiments. However, the practical applications of mica are relatively limited compared to those of semiconductor substrates. For this reason, a straightforward, stable, and repeatable process for DNA origami adhesion on derivatized silicon oxide is presented here. To promote the adhesion of DNA nanostructures to silicon oxide surface, a self-assembled monolayer of 3-aminopropyltriethoxysilane (APTES) is deposited from an aqueous solution that is compatible with many photoresists. The substrate must be cleaned of all organic and metal contaminants using Radio Corporation of America (RCA) cleaning processes and the native oxide layer must be etched to ensure a flat, functionalizable surface. Cleanrooms are equipped with facilities for silicon cleaning, however many components of DNA origami buffers and solutions are often not allowed in them due to contamination concerns. This manuscript describes the set-up and protocol for in-lab, small-scale silicon cleaning for researchers who do not have access to a cleanroom or would like to incorporate processes that could cause contamination of a cleanroom CMOS clean bench. Additionally, variables for regulating coverage are discussed and how to recognize and avoid common sample preparation problems is described.
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Affiliation(s)
| | - Rebecca Shute
- Department of Chemistry and Biochemistry, University of Notre Dame
| | - Adam Farchone
- Department of Chemical and Biomolecular Engineering, University of Notre Dame
| | - Keenan P Linder
- Department of Chemistry, Physics, and Engineering Studies, Chicago State University
| | - Rose Doerfler
- Department of Chemical and Biomolecular Engineering, University of Notre Dame
| | - Corey Gavin
- Department of Technology, Ivy Tech Community College, South Bend, Indiana
| | - Valerie Goss
- Department of Chemistry, Physics, and Engineering Studies, Chicago State University
| | - Marya Lieberman
- Department of Chemistry and Biochemistry, University of Notre Dame
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30
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Study of DNA adsorption on mica surfaces using a surface force apparatus. Sci Rep 2015; 5:8442. [PMID: 25676333 PMCID: PMC4326959 DOI: 10.1038/srep08442] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 01/19/2015] [Indexed: 11/22/2022] Open
Abstract
We report our studies on the adsorption properties of double-stranded DNA molecules on mica surfaces in a confined environment using a surface force apparatus. Specifically, we studied the influence of cation species and concentrations on DNA adsorption properties. Our results indicated that divalent cations (Mg2+ and Co2+) preferred to form uniform and moderately dense DNA layers on a mica substrate. By measuring the interactions between DNA-coated mica and bare mica in an aqueous solution, obvious adhesion was observed in a cobalt chloride solution, possibly due to the ion-correlation attraction between negatively charged DNA and the mica surface. Furthermore, the interaction differences that were observed with MgCl2 and CoCl2 solutions reveal that the specific adsorption behaviors of DNA molecules on a mica substrate were mediated by these two salts. Our results are helpful to elucidate the dynamics of DNA binding on a solid substrate.
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31
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Woo S, Rothemund PWK. Self-assembly of two-dimensional DNA origami lattices using cation-controlled surface diffusion. Nat Commun 2014; 5:4889. [PMID: 25205175 DOI: 10.1038/ncomms5889] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 08/01/2014] [Indexed: 12/24/2022] Open
Abstract
DNA origami has proven useful for organizing diverse nanoscale components into patterns with 6 nm resolution. However for many applications, such as nanoelectronics, large-scale organization of origami into periodic lattices is desired. Here, we report the self-assembly of DNA origami rectangles into two-dimensional lattices based on stepwise control of surface diffusion, implemented by changing the concentrations of cations on the surface. Previous studies of DNA–mica binding identified the fractional surface density of divalent cations (ñ(s2))as the parameter which best explains the behaviour of linear DNA on mica. We show that for ñ(s2) between 0.04 and 0.1, over 90% of DNA rectangles were incorporated into lattices and that, compared with other functions of cation concentration, ñ(s2) best captures the behaviour of DNA rectangles. This work shows how a physical understanding of DNA–mica binding can be used to guide studies of the higher-order assembly of DNA nanostructures, towards creating large-scale arrays of nanodevices for technology.
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Affiliation(s)
- Sungwook Woo
- Department of Bioengineering, California Institute of Technology, Pasadena, California 91125, USA
| | - Paul W K Rothemund
- 1] Department of Bioengineering, California Institute of Technology, Pasadena, California 91125, USA [2] Department of Computer Science, California Institute of Technology, Pasadena, California 91125, USA [3] Department of Computation &Neural Systems, California Institute of Technology, Pasadena, California 91125, USA
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32
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Bounedjah O, Desforges B, Wu TD, Pioche-Durieu C, Marco S, Hamon L, Curmi PA, Guerquin-Kern JL, Piétrement O, Pastré D. Free mRNA in excess upon polysome dissociation is a scaffold for protein multimerization to form stress granules. Nucleic Acids Res 2014; 42:8678-91. [PMID: 25013173 PMCID: PMC4117795 DOI: 10.1093/nar/gku582] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 06/12/2014] [Accepted: 06/17/2014] [Indexed: 12/12/2022] Open
Abstract
The sequence of events leading to stress granule assembly in stressed cells remains elusive. We show here, using isotope labeling and ion microprobe, that proportionally more RNA than proteins are present in stress granules than in surrounding cytoplasm. We further demonstrate that the delivery of single strand polynucleotides, mRNA and ssDNA, to the cytoplasm can trigger stress granule assembly. On the other hand, increasing the cytoplasmic level of mRNA-binding proteins like YB-1 can directly prevent the aggregation of mRNA by forming isolated mRNPs, as evidenced by atomic force microscopy. Interestingly, we also discovered that enucleated cells do form stress granules, demonstrating that the translocation to the cytoplasm of nuclear prion-like RNA-binding proteins like TIA-1 is dispensable for stress granule assembly. The results lead to an alternative view on stress granule formation based on the following sequence of events: after the massive dissociation of polysomes during stress, mRNA-stabilizing proteins like YB-1 are outnumbered by the burst of nonpolysomal mRNA. mRNA freed of ribosomes thus becomes accessible to mRNA-binding aggregation-prone proteins or misfolded proteins, which induces stress granule formation. Within the frame of this model, the shuttling of nuclear mRNA-stabilizing proteins to the cytoplasm could dissociate stress granules or prevent their assembly.
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Affiliation(s)
- Ouissame Bounedjah
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR829; Université Evry-Val d'Essonne, Evry 91025, France
| | - Bénédicte Desforges
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR829; Université Evry-Val d'Essonne, Evry 91025, France
| | - Ting-Di Wu
- Institut Curie, INSERM, U759, 91405 Orsay cedex, France
| | - Catherine Pioche-Durieu
- Centre National de la Recherche Scientifique (CNRS), UMR 8126; University of Paris Sud, 94805 Villejuif, France
| | - Sergio Marco
- Institut Curie, INSERM, U759, 91405 Orsay cedex, France
| | - Loic Hamon
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR829; Université Evry-Val d'Essonne, Evry 91025, France
| | - Patrick A Curmi
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR829; Université Evry-Val d'Essonne, Evry 91025, France
| | | | - Olivier Piétrement
- Centre National de la Recherche Scientifique (CNRS), UMR 8126; University of Paris Sud, 94805 Villejuif, France
| | - David Pastré
- Institut National de la Santé et de la Recherche Médicale (INSERM), UMR829; Université Evry-Val d'Essonne, Evry 91025, France
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33
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Billingsley DJ, Lee AJ, Johansson NAB, Walton A, Stanger L, Crampton N, Bonass WA, Thomson NH. Patchiness of ion-exchanged mica revealed by DNA binding dynamics at short length scales. NANOTECHNOLOGY 2014; 25:025704. [PMID: 24334563 DOI: 10.1088/0957-4484/25/2/025704] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The binding of double-stranded (ds) DNA to mica can be controlled through ion-exchanging the mica with divalent cations. Measurements of the end-to-end distance of linear DNA molecules discriminate whether the binding mechanism occurs through 2D surface equilibration or kinetic trapping. A range of linear dsDNA fragments have been used to investigate length dependences of binding. Mica, ion-exchanged with Ni(II) usually gives rise to kinetically trapped DNA molecules, however, short linear fragments (<800 bp) are seen to deviate from the expected behaviour. This indicates that ion-exchanged mica is heterogeneous, and contains patches or domains, separating different ionic species. These results correlate with imaging of dsDNA under aqueous buffer on Ni(II)-mica and indicate that binding domains are of the order of 100 nm in diameter. Shorter DNA fragments behave intermediate to the two extreme cases of 2D equilibration and kinetic trapping. Increasing the incubation time of Ni(II) on mica, from minutes to hours, brings the conformations of the shorter DNA fragments closer to the theoretical value for kinetic trapping, indicating that long timescale kinetics play a role in ion-exchange. X-ray photoelectron spectroscopy (XPS) was used to confirm that the relative abundance of Ni(II) ions on the mica surface increases with time. These findings can be used to enhance spatial control of binding of DNA to inorganic surfaces with a view to patterning high densities arrays.
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Affiliation(s)
- D J Billingsley
- School of Physics and Astronomy, University of Leeds, Woodhouse Lane, Leeds, West Yorkshire LS2 9JT, UK. Department of Oral Biology, School of Dentistry, University of Leeds, Woodhouse Lane, Leeds, West Yorkshire LS2 9LU, UK
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34
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Pastré D, Joshi V, Curmi PA, Hamon L. Detection of single DNA molecule hybridization on a surface by atomic force microscopy. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:3630-3638. [PMID: 23674511 DOI: 10.1002/smll.201300546] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Indexed: 06/02/2023]
Abstract
Improving the detection of DNA hybridization is a critical issue for several challenging applications encountered in microarray and biosensor domains. Herein, it is demonstrated that hybridization between complementary single-stranded DNA (ssDNA) molecules loosely adsorbed on a mica surface can be achieved thanks to fine-tuning of the composition of the hybridization buffer. Single-molecule DNA hybridization occurs in only a few minutes upon encounters of freely diffusing complementary strands on the mica surface. Interestingly, the specific hybridization between complementary ssDNA is not altered in the presence of large amounts of nonrelated DNA. The detection of single-molecule DNA hybridization events is performed by measuring the contour length of DNA in atomic force microscopy images. Besides the advantage provided by facilitated diffusion, which promotes hybridization between probes and targets on mica, the present approach also allows the detection of single isolated DNA duplexes and thus requires a very low amount of both probe and target molecules.
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Affiliation(s)
- David Pastré
- Inserm U829, Laboratoire Structure-Activité des, Biomolécules Normales et Pathologiques, Université d'Evry-Val d'Essonne, Evry 91025, France
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35
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Jiang L, Titmuss S, Klein J. Interactions of hyaluronan layers with similarly charged surfaces: the effect of divalent cations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:12194-12202. [PMID: 24011082 DOI: 10.1021/la401931y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We used colloidal probe atomic force microscopy to measure the normal forces between the surface of a silica colloidal particle and a sparse layer of hyaluronan (hyaluronic acid, HA, MW ≈ 10(6) Da) covalently attached to a planar silica surface, both across pure water and following the addition of 1 mM MgCl2. It was found that in the absence of salt the HA layer repelled the colloidal silica surface during both approach and retraction. The addition of the MgCl2, however, changes the net force between the negatively charged HA layer and the opposing negatively charged silica surface from repulsion to adhesion. This interaction reversal is attributed to the bridging effect of the added Mg(2+) ions. Our results provide first direct force data to support earlier simulation and predictions that such divalent cations could bridge between negative charges on opposing surfaces, leading to an overall reversal of force from repulsion to attraction.
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Affiliation(s)
- Lei Jiang
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, China University of Petroleum , 66 Changjiang West Road, Qingdao, Shandong 266580, P. R. China
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36
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Rittich B, Španová A. SPE and purification of DNA using magnetic particles. J Sep Sci 2013; 36:2472-85. [DOI: 10.1002/jssc.201300331] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 05/13/2013] [Accepted: 05/13/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Bohuslav Rittich
- Faculty of Chemistry; Brno University of Technology; Brno Czech Republic
| | - Alena Španová
- Faculty of Chemistry; Brno University of Technology; Brno Czech Republic
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37
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Huang F, Liang H. Adsorption behaviors of DNA/cation complexes on amino and silica chip surfaces: a dual polarization interferometry study. ACS APPLIED MATERIALS & INTERFACES 2013; 5:5025-5033. [PMID: 23697755 DOI: 10.1021/am400813x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The adsorption of DNA/Ca(2+), DNA/Cu(2+), and DNA/Co(NH3)6(3+) complexes on amino and silica chip surfaces were investigated using dual polarization interferometry. A more compact DNA/cation complex layer formed on the amino chip surface compared with that on the silica chip surface at the same cation condition. The real-time mass, thickness, and density changes were monitored during the adsorption process. The overall results show that the approaching complexes can cause the conformation rearrangement of the preadsorbed complexes and the preadsorbed complexes affect the deposition pattern of the approaching complexes during the adsorption of DNA/Ca(2+) and DNA/Cu(2+) complexes on both chip surfaces. The relatively strong electrostatic repulsion between the approaching and adsorbed complexes results in multiple mass loading rate changes and loose attachment of the approaching complexes. The weak repulsion between the DNA/Co(NH3)6(3+) complexes cannot induce this kind of conformation rearrangement. Thus, no multiple mass loading rate changes were observed. Meanwhile, the preadsorbed DNA/Co(NH3)6(3+) complex can also affect the deposition pattern of the approaching complex because of the geometric resistance. Therefore, this study will help better understand the conformation change and deposition pattern of complexes with different charge conditions during the adsorption process on the solid-liquid interface.
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Affiliation(s)
- Fujian Huang
- CAS Key Laboratory of Soft Matter Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, People's Republic of China
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38
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Gao ZF, Gao JB, Zhou LY, Zhang Y, Si JC, Luo HQ, Li NB. Rapid assembly of ssDNA on gold electrode surfaces at low pH and high salt concentration conditions. RSC Adv 2013. [DOI: 10.1039/c3ra40810h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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39
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Vandeventer PE, Lin JS, Zwang TJ, Nadim A, Johal MS, Niemz A. Multiphasic DNA adsorption to silica surfaces under varying buffer, pH, and ionic strength conditions. J Phys Chem B 2012; 116:5661-70. [PMID: 22537288 DOI: 10.1021/jp3017776] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Reversible interactions between DNA and silica are utilized in the solid phase extraction and purification of DNA from complex samples. Chaotropic salts commonly drive DNA binding to silica but inhibit DNA polymerase amplification. We studied DNA adsorption to silica using conditions with or without chaotropic salts through bulk depletion and quartz crystal microbalance (QCM) experiments. While more DNA adsorbed to silica using chaotropic salts, certain buffer conditions without chaotropic salts yielded a similar amount of eluted DNA. QCM results indicate that under stronger adsorbing conditions the adsorbed DNA layer is initially rigid but becomes viscoelastic within minutes. These results qualitatively agreed with a mathematical model for a multiphasic adsorption process. Buffer conditions that do not require chaotropic salts can simplify protocols for nucleic acid sample preparation. Understanding how DNA adsorbs to silica can help optimize nucleic acid sample preparation for clinical diagnostic and research applications.
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Affiliation(s)
- Peter E Vandeventer
- Keck Graduate Institute of Applied Life Sciences , 535 Watson Drive, Claremont, California 91711, United States
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40
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Superparamagnetic core–shell structured microspheres carrying carboxyl groups as adsorbents for purification of genomic DNA. Colloids Surf A Physicochem Eng Asp 2012. [DOI: 10.1016/j.colsurfa.2012.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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41
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Billingsley DJ, Bonass WA, Crampton N, Kirkham J, Thomson NH. Single-molecule studies of DNA transcription using atomic force microscopy. Phys Biol 2012; 9:021001. [PMID: 22473059 DOI: 10.1088/1478-3975/9/2/021001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Atomic force microscopy (AFM) can detect single biomacromolecules with a high signal-to-noise ratio on atomically flat biocompatible support surfaces, such as mica. Contrast arises from the innate forces and therefore AFM does not require imaging contrast agents, leading to sample preparation that is relatively straightforward. The ability of AFM to operate in hydrated environments, including humid air and aqueous buffers, allows structure and function of biological and biomolecular systems to be retained. These traits of the AFM are ensuring that it is being increasingly used to study deoxyribonucleic acid (DNA) structure and DNA-protein interactions down to the secondary structure level. This report focuses in particular on reviewing the applications of AFM to the study of DNA transcription in reductionist single-molecule bottom-up approaches. The technique has allowed new insights into the interactions between ribonucleic acid (RNA) polymerase to be gained and enabled quantification of some aspects of the transcription process, such as promoter location, DNA wrapping and elongation. More recently, the trend is towards studying the interactions of more than one enzyme operating on a single DNA template. These methods begin to reveal the mechanics of gene expression at the single-molecule level and will enable us to gain greater understanding of how the genome is transcribed and translated into the proteome.
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Affiliation(s)
- Daniel J Billingsley
- School of Physics and Astronomy, University of Leeds, Woodhouse Lane, Leeds, West Yorkshire LS2 9JT, UK
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42
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Hamada S, Murata S. Theoretical model of substrate-assisted self-assembly of DNA nanostructures. RSC Adv 2012. [DOI: 10.1039/c2ra20764h] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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43
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Li C, Tian H, Duan S, Liu X, Xu P, Qiao R, Zhao Y. Controllable DNA Condensation-Release Induced by Simple Azaheterocyclic-Based Metal Complexes. J Phys Chem B 2011; 115:13350-4. [DOI: 10.1021/jp206199b] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chao Li
- State Key Laboratory of Chemical Resource Engineering, Department of Pharmaceutical Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Hua Tian
- State Key Laboratory of Chemical Resource Engineering, Department of Pharmaceutical Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Shan Duan
- State Key Laboratory of Chemical Resource Engineering, Department of Pharmaceutical Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Xuena Liu
- State Key Laboratory of Chemical Resource Engineering, Department of Pharmaceutical Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
| | - Pengfei Xu
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, P. R. China
| | - Renzhong Qiao
- State Key Laboratory of Chemical Resource Engineering, Department of Pharmaceutical Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China
- State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, P. R. China
| | - Yufen Zhao
- Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361006, P. R. China
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44
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Hung AM, Cha JN. Templated assembly of DNA origami gold nanoparticle arrays on lithographically patterned surfaces. Methods Mol Biol 2011; 749:187-97. [PMID: 21674373 DOI: 10.1007/978-1-61779-142-0_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Artificial DNA nanostructures such as DNA origami have garnered significant interest as templates for sub-20 nm lithography because their rational design allows for the incorporation of binding sites to assemble nanocomponents with 6 nm resolution. In addition, their overall size of 100 nm is easily accessible by top-down lithographic methods. Combining the strengths of top-down lithography and bottom-up self-assembly using DNA nanostructures may provide a commercially viable route to fabricating electronic and photonic devices with nanometer-scale features. We have demonstrated just such a comprehensive process in which 5 nm gold nanoparticles are first assembled in high yield on DNA origami. The constructs are then organized, rinsed, and dried on patterned silicon substrates, yielding large area arrays of both origami and nanoparticles.
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Affiliation(s)
- Albert M Hung
- Department of Nanoengineering, UC San Diego, La Jolla, CA, USA
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45
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Hung AM, Noh H, Cha JN. Recent advances in DNA-based directed assembly on surfaces. NANOSCALE 2010; 2:2530-2537. [PMID: 20835482 DOI: 10.1039/c0nr00430h] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In the last decade, "small" and "integrated" have been keywords in the field of device fabrication as the desire to exploit nanoscale phenomena and make electronic, photonic and magnetic arrays has grown. In an effort to improve resolution and control costs, much work has been dedicated to developing alternatives to conventional microfabrication technology. For this purpose, biomolecular assembly and DNA nanotechnology in particular are appealing owing to their inherent size and capacity for molecular recognition. Herein, we review recent achievements in DNA-based directed assembly on substrates. These include novel methods for patterning and depositing nanomaterials on DNA-modified surfaces as well as using synthetic DNA nanostructures such as DNA tiles and origami as templates to direct the assembly of nanoscale components. Particular attention is paid to integrating self-assembly with top-down lithography, and some possible directions for future work are discussed.
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Affiliation(s)
- Albert M Hung
- Department of Nanoengineering, University of CA, San Diego, CA, USA
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46
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Hsueh C, Chen H, Gimzewski JK, Reed J, Abdel-Fattah TM. Localized nanoscopic surface measurements of nickel-modified mica for single-molecule DNA sequence sampling. ACS APPLIED MATERIALS & INTERFACES 2010; 2:3249-56. [PMID: 21033675 PMCID: PMC3010388 DOI: 10.1021/am100697z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Cleaved, cation-derivatized Muscovite mica is utilized extensively in atomic force microscopy (AFM) imaging because of its flatness over large areas (millimeter cleavage planes with local root-mean-square roughness < 0.3 nm), ease of preparation, and ability to adsorb charged biomolecules such as DNA (work by Hansma and Laney, Guthold et al., and McMaster et al.). In particular, NiCl(2) treatment has become a common method for controlling DNA adsorption on mica substrates while retaining the mica's ultraflat surface (work by Pietrement et al.). While several studies have modeled the mica/metal ion/DNA system using macroscopic colloidal theory (DLVO, etc.; Pietrement et al., Sushko et al., Pastre et al., and Cheng et al.), nickel/mica's physicochemical properties have not been well characterized on the nanoscale. Efforts to manipulate and engineer DNA nanostructures would benefit greatly from a better understanding of the surface chemistry of nickel/mica. Here we present in situ nanometer- and attogram-scale measurements and thermodynamic simulation results that show that the surface chemistry of nickel-treated mica is more complex than generally appreciated by AFM practitioners because of metal-ion speciation effects present at neutral pH. We also show that, under certain preparations, nickel/mica allows in situ nanoscopic nucleotide sequence mapping within individual surface-adsorbed DNA molecules by permitting localized, controlled desorption of the double helix by soluble DNA binding enzymes. These results should aid efforts to precisely control the DNA/mica binding affinity, particularly at the physiological pH ranges required by enzymatic biochemistry (pH 7.0-8.5), and facilitate the development of more complex and useful biochemical manipulations of adsorbed DNA, such as single-molecule sequencing.
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Affiliation(s)
- Carlin Hsueh
- Department of Chemistry and Biochemistry, UCLA, 607 Charles Young Drive East, Los Angeles, California
| | - Haijian Chen
- Department of Physics, College of William and Mary, Williamsburg, VA, 23185
| | - James K. Gimzewski
- Department of Chemistry and Biochemistry, UCLA, 607 Charles Young Drive East, Los Angeles, California
- UCLA California NanoSystems Institute (CNSI), 570 Westwood Plaza, Los Angeles, CA 90095
| | - Jason Reed
- UCLA California NanoSystems Institute (CNSI), 570 Westwood Plaza, Los Angeles, CA 90095
| | - Tarek M. Abdel-Fattah
- Applied Research Center, Jefferson National Laboratory and Department of Biology, Chemistry and Environmental Science, Christopher Newport University, Newport News, VA 23606
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47
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Billingsley DJ, Kirkham J, Bonass WA, Thomson NH. Atomic force microscopy of DNA at high humidity: irreversible conformational switching of supercoiled molecules. Phys Chem Chem Phys 2010; 12:14727-34. [PMID: 20927466 DOI: 10.1039/c0cp01347a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Three topologically different double-stranded DNA molecules of the same size (bps) have been imaged in air on mica using amplitude modulation atomic force microscopy (AM AFM) under controlled humidity conditions. At very high relative humidity (>90% RH), localized conformational changes of the DNA were observed, while at lower RH, the molecules remained immobile. The conformational changes occurred irreversibly and were driven principally by superhelical stress stored in the DNA molecules prior to binding to the mica surface. The binding mechanism of the DNA to the mica (surface equilibration versus kinetic trapping) modulated the extent of the conformational changes. In cases where DNA movement was observed, increased kinking of the DNA was seen at high humidity when more surface water was present. Additionally, DNA condensation behavior was also present in localized regions of the molecules. This study illustrates that changes in the tertiary structure of DNA can be induced during AFM imaging at high humidity on mica. We propose that AM AFM in high humidity will be a useful technique for probing DNA topology without some of the drawbacks of imaging under bulk solution.
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Affiliation(s)
- Daniel J Billingsley
- School of Physics & Astronomy, University of Leeds, Woodhouse Lane, Leeds, West Yorkshire, UK LS2 9JT
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Pastré D, Hamon L, Sorel I, Le Cam E, Curmi PA, Piétrement O. Specific DNA-protein interactions on mica investigated by atomic force microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:2618-2623. [PMID: 19791748 DOI: 10.1021/la902727b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
DNA processing by site-specific proteins on surface remains a challenging issue for nanobioscience applications and, in particular, for high-resolution imaging by atomic force microscopy (AFM). To obtain high-resolution conditions, mica, an atomically flat and negatively charged surface, is generally used. However, even though many specific DNA/protein interactions have already been observed by AFM, little is known about DNA accessibility to specific enzymes on mica. Here we measured the accessibility of adsorbed DNA to restriction endonucleases (EcoRI and EcoRV) using AFM. By increasing the concentration of divalent or multivalent salts, DNA adsorption on mica switches from weak to strong binding. Interestingly, while the accessibility of strongly bound DNA was inhibited, loosely adsorbed DNA was efficiently cleaved on mica. This result opens new perspective to study DNA/protein interaction by AFM or to modify specifically DNA on surface.
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Affiliation(s)
- David Pastré
- Laboratoire Structure et Activité des Biomolécules Normales et Pathologiques, INSERM/UEVE U829, Université d'Evry val d'Essonne, Evry F-91025, France.
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49
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Hamon L, Curmi PA, Pastré D. High-resolution imaging of microtubules and cytoskeleton structures by atomic force microscopy. Methods Cell Biol 2010; 95:157-74. [PMID: 20466134 DOI: 10.1016/s0091-679x(10)95009-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Atomic force microscopy (AFM), which combines a nanometer-scale resolution and a unique capacity to image biomolecular interactions in liquid environment, is a promising tool for the investigation of biological samples. In contrast with nucleic acids and nucleoprotein complexes, for which AFM is now of common use and participates in the recent advances in the knowledge of DNA-related biomolecular processes, AFM investigations of cytoskeleton structures and especially microtubules remain rare. The most critical step to observe biomolecules using AFM is the spreading of the biological material on a flat surface. This issue is now better documented concerning DNA but a lot remains to be done concerning microtubules. This is a prerequisite to further document this issue for a proper and large use of AFM to study cytoskeleton structures. We present here an overview of the various procedures previously used to spread microtubules on a flat surface and advance an easy-to-use and efficient experimental protocol for microtubule imaging by AFM in air. We show application of this protocol to observe intermediate structures of microtubule assembly without using any stabilizing agent and the observation of more complex systems like proteins or messenger ribonucleoprotein particles in interaction with microtubules.
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Affiliation(s)
- Loic Hamon
- Laboratoire Structure-Activité des Biomolécules Normales et Pathologiques, INSERM - UEVE UMR U829, Evry 91025, France
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Kershner RJ, Bozano LD, Micheel CM, Hung AM, Fornof AR, Cha JN, Rettner CT, Bersani M, Frommer J, Rothemund PWK, Wallraff GM. Placement and orientation of individual DNA shapes on lithographically patterned surfaces. NATURE NANOTECHNOLOGY 2009; 4:557-61. [PMID: 19734926 DOI: 10.1038/nnano.2009.220] [Citation(s) in RCA: 253] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Accepted: 07/07/2009] [Indexed: 05/24/2023]
Abstract
Artificial DNA nanostructures show promise for the organization of functional materials to create nanoelectronic or nano-optical devices. DNA origami, in which a long single strand of DNA is folded into a shape using shorter 'staple strands', can display 6-nm-resolution patterns of binding sites, in principle allowing complex arrangements of carbon nanotubes, silicon nanowires, or quantum dots. However, DNA origami are synthesized in solution and uncontrolled deposition results in random arrangements; this makes it difficult to measure the properties of attached nanodevices or to integrate them with conventionally fabricated microcircuitry. Here we describe the use of electron-beam lithography and dry oxidative etching to create DNA origami-shaped binding sites on technologically useful materials, such as SiO(2) and diamond-like carbon. In buffer with approximately 100 mM MgCl(2), DNA origami bind with high selectivity and good orientation: 70-95% of sites have individual origami aligned with an angular dispersion (+/-1 s.d.) as low as +/-10 degrees (on diamond-like carbon) or +/-20 degrees (on SiO(2)).
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Affiliation(s)
- Ryan J Kershner
- IBM Almaden Research Center, San Jose, California 95120, USA
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