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Li X, Jin K, Cheng TC, Liao YC, Lee WJ, Bhullar AS, Chen LC, Rychahou P, Phelps MA, Ho YS, Guo P. RNA four-way junction (4WJ) for spontaneous cancer-targeting, effective tumor-regression, metastasis suppression, fast renal excretion and undetectable toxicity. Biomaterials 2024; 305:122432. [PMID: 38176263 PMCID: PMC10994150 DOI: 10.1016/j.biomaterials.2023.122432] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 11/14/2023] [Accepted: 12/14/2023] [Indexed: 01/06/2024]
Abstract
The field of RNA therapeutics has been emerging as the third milestone in pharmaceutical drug development. RNA nanoparticles have displayed motile and deformable properties to allow for high tumor accumulation with undetectable healthy organ accumulation. Therefore, RNA nanoparticles have the potential to serve as potent drug delivery vehicles with strong anti-cancer responses. Herein, we report the physicochemical basis for the rational design of a branched RNA four-way junction (4WJ) nanoparticle that results in advantageous high-thermostability and -drug payload for cancer therapy, including metastatic tumors in the lung. The 4WJ nanostructure displayed versatility through functionalization with an anti-cancer chemical drug, SN38, for the treatment of two different cancer models including colorectal cancer xenograft and orthotopic lung metastases of colon cancer. The resulting 4WJ RNA drug complex spontaneously targeted cancers effectively for cancer inhibition with and without ligands. The 4WJ displayed fast renal excretion, rapid body clearance, and little organ accumulation with undetectable toxicity and immunogenicity. The safety parameters were documented by organ histology, blood biochemistry, and pathological analysis. The highly efficient cancer inhibition, undetectable drug toxicity, and favorable Chemical, Manufacturing, and Control (CMC) production of RNA nanoparticles document a candidate with high potential for translation in cancer therapy.
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Affiliation(s)
- Xin Li
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA; Center for RNA Nanotechnology and Nanomedicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Kai Jin
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA; Center for RNA Nanotechnology and Nanomedicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Tzu-Chun Cheng
- Institute of Biochemistry and Molecular Biology, China Medical University, Taichung, 406040, Taiwan
| | - You-Cheng Liao
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taipei, 110031, Taiwan
| | - Wen-Jui Lee
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA; Center for RNA Nanotechnology and Nanomedicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Abhjeet S Bhullar
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA; Center for RNA Nanotechnology and Nanomedicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Li-Ching Chen
- Department of Biological Science & Technology, China Medical University, Taichung, 406040, Taiwan
| | - Piotr Rychahou
- Markey Cancer Center, Department of Surgery, University of Kentucky, Lexington, KY, 40536, USA
| | - Mitch A Phelps
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA; Center for RNA Nanotechnology and Nanomedicine, The Ohio State University, Columbus, OH, 43210, USA
| | - Yuan Soon Ho
- Institute of Biochemistry and Molecular Biology, China Medical University, Taichung, 406040, Taiwan.
| | - Peixuan Guo
- Division of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, OH, 43210, USA; Center for RNA Nanotechnology and Nanomedicine, The Ohio State University, Columbus, OH, 43210, USA; James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, OH, 43210, USA; Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH, 43210, USA.
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2
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Poppleton E, Urbanek N, Chakraborty T, Griffo A, Monari L, Göpfrich K. RNA origami: design, simulation and application. RNA Biol 2023; 20:510-524. [PMID: 37498217 PMCID: PMC10376919 DOI: 10.1080/15476286.2023.2237719] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 06/20/2023] [Accepted: 07/12/2023] [Indexed: 07/28/2023] Open
Abstract
Design strategies for DNA and RNA nanostructures have developed along parallel lines for the past 30 years, from small structural motifs derived from biology to large 'origami' structures with thousands to tens of thousands of bases. With the recent publication of numerous RNA origami structures and improved design methods-even permitting co-transcriptional folding of kilobase-sized structures - the RNA nanotechnolgy field is at an inflection point. Here, we review the key achievements which inspired and enabled RNA origami design and draw comparisons with the development and applications of DNA origami structures. We further present the available computational tools for the design and the simulation, which will be key to the growth of the RNA origami community. Finally, we portray the transition from RNA origami structure to function. Several functional RNA origami structures exist already, their expression in cells has been demonstrated and first applications in cell biology have already been realized. Overall, we foresee that the fast-paced RNA origami field will provide new molecular hardware for biophysics, synthetic biology and biomedicine, complementing the DNA origami toolbox.
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Affiliation(s)
- Erik Poppleton
- Biophysical Engineering Group, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg University, Heidelberg, Germany
- Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
- Molecular Biomechanics, Heidelberg Institute for Theoretical Studies (HITS), Heidelberg, Germany
| | - Niklas Urbanek
- Biophysical Engineering Group, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg University, Heidelberg, Germany
- Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Taniya Chakraborty
- Biophysical Engineering Group, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg University, Heidelberg, Germany
- Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Alessandra Griffo
- Biophysical Engineering Group, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg University, Heidelberg, Germany
- Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Luca Monari
- Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
- Institut de Science Et D’ingénierie Supramoléculaires (ISIS), Université de Strasbourg, Strasbourg, France
| | - Kerstin Göpfrich
- Biophysical Engineering Group, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg University, Heidelberg, Germany
- Biophysical Engineering Group, Max Planck Institute for Medical Research, Heidelberg, Germany
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Coupled Multiphysics Modelling of Sensors for Chemical, Biomedical, and Environmental Applications with Focus on Smart Materials and Low-Dimensional Nanostructures. CHEMOSENSORS 2022; 10:157. [PMID: 35909810 PMCID: PMC9171916 DOI: 10.3390/chemosensors10050157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/22/2022] [Indexed: 12/20/2022]
Abstract
Low-dimensional nanostructures have many advantages when used in sensors compared to the traditional bulk materials, in particular in their sensitivity and specificity. In such nanostructures, the motion of carriers can be confined from one, two, or all three spatial dimensions, leading to their unique properties. New advancements in nanosensors, based on low-dimensional nanostructures, permit their functioning at scales comparable with biological processes and natural systems, allowing their efficient functionalization with chemical and biological molecules. In this article, we provide details of such sensors, focusing on their several important classes, as well as the issues of their designs based on mathematical and computational models covering a range of scales. Such multiscale models require state-of-the-art techniques for their solutions, and we provide an overview of the associated numerical methodologies and approaches in this context. We emphasize the importance of accounting for coupling between different physical fields such as thermal, electromechanical, and magnetic, as well as of additional nonlinear and nonlocal effects which can be salient features of new applications and sensor designs. Our special attention is given to nanowires and nanotubes which are well suited for nanosensor designs and applications, being able to carry a double functionality, as transducers and the media to transmit the signal. One of the key properties of these nanostructures is an enhancement in sensitivity resulting from their high surface-to-volume ratio, which leads to their geometry-dependant properties. This dependency requires careful consideration at the modelling stage, and we provide further details on this issue. Another important class of sensors analyzed here is pertinent to sensor and actuator technologies based on smart materials. The modelling of such materials in their dynamics-enabled applications represents a significant challenge as we have to deal with strongly nonlinear coupled problems, accounting for dynamic interactions between different physical fields and microstructure evolution. Among other classes, important in novel sensor applications, we have given our special attention to heterostructures and nucleic acid based nanostructures. In terms of the application areas, we have focused on chemical and biomedical fields, as well as on green energy and environmentally-friendly technologies where the efficient designs and opportune deployments of sensors are both urgent and compelling.
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FALLAHPOUR ROSA, MELNIK RODERICK. A MOLECULAR DYNAMICS STUDY OF NANOWIRE RESONATOR BIO-OBJECT DETECTION. J MECH MED BIOL 2021. [DOI: 10.1142/s0219519422500038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This paper presents a comprehensive analysis, carried out by the molecular dynamics (MD) simulations, of the vibrations of silicon nanowire (SiNW) resonators, having diverse applications including biological and medical fields. The chosen approach allows us to obtain a better understanding of the nanowire (NW) materials’ characteristics, providing a more detailed insight into the behavior of nanostructures, especially when the topic of interest is relevant to their dynamics, interatomic interactions, and atoms trajectories’ prediction. We first simulate a SiNW to study its frequency of vibrations using MD simulations. Then, we add a molecule of human immunodeficiency virus as an example to investigate the potential of the SiNW resonator for the detection of tiny bio-objects. The developed technique and its application to the detection of tiny objects, such as viruses, are discussed in the context of several key effects pertinent to the design of SiNW.
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Affiliation(s)
- ROSA FALLAHPOUR
- The MS2Discovery Interdisciplinary Research Institute, M2NeT Laboratory, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
| | - RODERICK MELNIK
- The MS2Discovery Interdisciplinary Research Institute, M2NeT Laboratory, Wilfrid Laurier University, Waterloo, ON N2L 3C5, Canada
- BCAM-Basque Center for Applied Mathematics, Alda. Mazarredo, Bilbao E-48009, Spain
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Binzel DW, Li X, Burns N, Khan E, Lee WJ, Chen LC, Ellipilli S, Miles W, Ho YS, Guo P. Thermostability, Tunability, and Tenacity of RNA as Rubbery Anionic Polymeric Materials in Nanotechnology and Nanomedicine-Specific Cancer Targeting with Undetectable Toxicity. Chem Rev 2021; 121:7398-7467. [PMID: 34038115 DOI: 10.1021/acs.chemrev.1c00009] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
RNA nanotechnology is the bottom-up self-assembly of nanometer-scale architectures, resembling LEGOs, composed mainly of RNA. The ideal building material should be (1) versatile and controllable in shape and stoichiometry, (2) spontaneously self-assemble, and (3) thermodynamically, chemically, and enzymatically stable with a long shelf life. RNA building blocks exhibit each of the above. RNA is a polynucleic acid, making it a polymer, and its negative-charge prevents nonspecific binding to negatively charged cell membranes. The thermostability makes it suitable for logic gates, resistive memory, sensor set-ups, and NEM devices. RNA can be designed and manipulated with a level of simplicity of DNA while displaying versatile structure and enzyme activity of proteins. RNA can fold into single-stranded loops or bulges to serve as mounting dovetails for intermolecular or domain interactions without external linking dowels. RNA nanoparticles display rubber- and amoeba-like properties and are stretchable and shrinkable through multiple repeats, leading to enhanced tumor targeting and fast renal excretion to reduce toxicities. It was predicted in 2014 that RNA would be the third milestone in pharmaceutical drug development. The recent approval of several RNA drugs and COVID-19 mRNA vaccines by FDA suggests that this milestone is being realized. Here, we review the unique properties of RNA nanotechnology, summarize its recent advancements, describe its distinct attributes inside or outside the body and discuss potential applications in nanotechnology, medicine, and material science.
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Affiliation(s)
- Daniel W Binzel
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Xin Li
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Nicolas Burns
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Eshan Khan
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, College of Medicine, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wen-Jui Lee
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Li-Ching Chen
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Satheesh Ellipilli
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wayne Miles
- Department of Cancer Biology and Genetics, The Ohio State University Comprehensive Cancer Center, College of Medicine, Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, United States
| | - Yuan Soon Ho
- TMU Research Center of Cancer Translational Medicine, School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Department of Laboratory Medicine, Taipei Medical University Hospital, Taipei 110, Taiwan
| | - Peixuan Guo
- Center for RNA Nanobiotechnology and Nanomedicine, College of Pharmacy, Dorothy M. Davis Heart and Lung Research Institute, James Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
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6
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Badu S, Melnik R, Singh S. Mathematical and computational models of RNA nanoclusters and their applications in data-driven environments. MOLECULAR SIMULATION 2020. [DOI: 10.1080/08927022.2020.1804564] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Shyam Badu
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
| | - Roderick Melnik
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
- BCAM-Basque Center for Applied Mathematics, Bilbao, Spain
| | - Sundeep Singh
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
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7
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Coarse-Grained Models of RNA Nanotubes for Large Time Scale Studies in Biomedical Applications. Biomedicines 2020; 8:biomedicines8070195. [PMID: 32640509 PMCID: PMC7400038 DOI: 10.3390/biomedicines8070195] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/16/2020] [Accepted: 07/04/2020] [Indexed: 01/13/2023] Open
Abstract
In order to describe the physical properties of large time scale biological systems, coarse-grained models play an increasingly important role. In this paper we develop Coarse-Grained (CG) models for RNA nanotubes and then, by using Molecular Dynamics (MD) simulation, we study their physical properties. Our exemplifications include RNA nanotubes of 40 nm long, equivalent to 10 RNA nanorings connected in series. The developed methodology is based on a coarse-grained representation of RNA nanotubes, where each coarse bead represents a group of atoms. By decreasing computation cost, this allows us to make computations feasible for realistic structures of interest. In particular, for the developed coarse-grained models with three bead approximations, we calculate the histograms for the bond angles and the dihedral angles. From the dihedral angle histograms, we analyze the characteristics of the links used to build the nanotubes. Furthermore, we also calculate the bead distances along the chains of RNA strands in the nanoclusters. The variations in these features with the size of the nanotube are discussed in detail. Finally, we present the results on the calculation of the root mean square deviations for a developed RNA nanotube to demonstrate the equilibration of the systems for drug delivery and other biomedical applications such as medical imaging and tissue engineering.
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Badu S, Prabhakar S, Melnik R, Singh S. Atomistic to continuum model for studying mechanical properties of RNA nanotubes. Comput Methods Biomech Biomed Engin 2020; 23:396-407. [PMID: 32116031 DOI: 10.1080/10255842.2020.1733991] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
With rapid advancements in the emerging field of RNA nanotechnology, its current and potential applications, new important problems arise in our quest to better understand properties of RNA nanocomplexes. In this paper, our focus is on the modeling of RNA nanotubes which are important for many biological processes. These RNA complexes are also important for human beings, with their theurapeutical and biomedical applications discussed vigorously in the literature over the recent years. Here, we develop a continuum model of RNA nanotubes, originally obtained from self assembly of RNA building blocks in the molecular dynamics simulation. Based on the finite element method, we calculate the elastic properties of these nanostructures and provide a relationship between stress and strain induced in the RNA nanotube. We also analyze the variations in the displacement vector along the assembly axis for RNA nanotubes of different sizes. In particular, we show that oscillations in the amplitudes of strains and displacements significantly differ for such RNA nanotubes. These findings are discussed in the context of atomistic simulations and experimental results in this field.
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Affiliation(s)
- Shyam Badu
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
| | - Sanjay Prabhakar
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
| | - Roderick Melnik
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada.,BCAM - Basque Center for Applied Mathematics, Bilbao, Spain
| | - Sundeep Singh
- MS2Discovery Interdisciplinary Research Institute, Wilfrid Laurier University, Waterloo, Ontario, Canada
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Naskar S, Joshi H, Chakraborty B, Seeman NC, Maiti PK. Atomic structures of RNA nanotubes and their comparison with DNA nanotubes. NANOSCALE 2019; 11:14863-14878. [PMID: 31355845 DOI: 10.1039/c9nr00786e] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We present a computational framework to model RNA based nanostructures and study their microscopic structures. We model hexagonal nanotubes made of 6 dsRNA (RNTs) connected by double crossover (DX) at different positions. Using several hundred nano-second (ns) long all-atom molecular dynamics simulations, we study the atomic structure, conformational change and elastic properties of RNTs in the presence of explicit water and ions. Based on several structural quantities such as root mean square deviation (RMSD) and root mean square fluctuation (RMSF), we find that the RNTs are almost as stable as DNA nanotubes (DNTs). Although the central portion of the RNTs maintain its cylindrical shape, both the terminal regions open up to give rise to a gating like behavior which can play a crucial role in drug delivery. From the bending angle distribution, we observe that the RNTs are more flexible than DNTs. The calculated persistence length of the RNTs is in the micron range which is an order of magnitude higher than that of a single dsRNA. The stretch modulus of the RNTs from the contour length distribution is in the range of 4-7 nN depending on the sequence. The calculated persistence length and stretch modulus are in the same range of values as in the case of DNTs. To understand the structural properties of RNTs at the individual base-pair level we have also calculated all the helicoidal parameters and analyzed the relative flexibility and rigidity of RNTs having a different sequence. These findings emphasized the fascinating properties of RNTs which will expedite further theoretical and experimental studies in this field.
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Affiliation(s)
- Supriyo Naskar
- Center for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore 560012, India.
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10
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Abstract
Molecular dynamics (MD) simulations have been used as one of the main research tools to study a wide range of biological systems and bridge the gap between X-ray crystallography or NMR structures and biological mechanism. In the field of RNA nanostructures, MD simulations have been used to fix steric clashes in computationally designed RNA nanostructures, characterize the dynamics, and investigate the interaction between RNA and other biomolecules such as delivery agents and membranes.In this chapter we present examples of computational protocols for molecular dynamics simulations in explicit and implicit solvent using the Amber Molecular Dynamics Package. We also show examples of post-simulation analysis steps and briefly mention selected tools beyond the Amber package. Limitations of the methods, tools, and protocols are also discussed. Most of the examples are illustrated for a small RNA duplex (helix), but the protocols are applicable to any nucleic acid structure, subject only to the computational speed and memory limitations of the hardware available to the user.
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Affiliation(s)
- Taejin Kim
- Department of Chemistry, New York University, 10th Floor Silver Center, 100 Washington Square East, New York, NY, 10003, USA
| | - Wojciech K Kasprzak
- Basic Science Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, 21702, USA
| | - Bruce A Shapiro
- RNA Structure and Design Section, RNA Biology Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD, 21702, USA.
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11
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Badu SR, Melnik R, Paliy M, Prabhakar S, Sebetci A, Shapiro BA. Modeling of RNA nanotubes using molecular dynamics simulation. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2014; 43:555-64. [PMID: 25208764 DOI: 10.1007/s00249-014-0985-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 08/14/2014] [Accepted: 08/21/2014] [Indexed: 01/11/2023]
Abstract
In this study, we construct novel RNA nanoclusters, RNA nanotubes made of several nanorings up to the size of 20 nm, utilizing the molecular dynamics simulation, and study their structural properties [i.e., the root mean square deviation, the radius of gyration and the radial distribution function (RDF)] in physiological solutions that can be used for drug delivery into the human body. The patterns of energy and temperature variations of the systems are also discussed. Furthermore, we study the concentration of ions around the tube as a function of time at a particular temperature. We have found that when the temperature increases, the number of ions increases within a certain distance of the tube. We report that the number of ions within this distance around the tubes decreases in quenched runs. This indicates that some ions evaporate with decrease in temperature, as has been observed in the case of the nanoring. RDF plots also demonstrate a similar trend with temperature, as was found in the case of RNA nanorings.
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Affiliation(s)
- S R Badu
- MS2Discovery Interdisciplinary Research Institute, M2Net Lab, Wilfrid Laurier University, 75 University Avenue, Waterloo, ON, N3L 3V6, Canada,
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12
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Schmitz U, Lai X, Winter F, Wolkenhauer O, Vera J, Gupta SK. Cooperative gene regulation by microRNA pairs and their identification using a computational workflow. Nucleic Acids Res 2014; 42:7539-52. [PMID: 24875477 PMCID: PMC4081082 DOI: 10.1093/nar/gku465] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
MicroRNAs (miRNAs) are an integral part of gene regulation at the post-transcriptional level. Recently, it has been shown that pairs of miRNAs can repress the translation of a target mRNA in a cooperative manner, which leads to an enhanced effectiveness and specificity in target repression. However, it remains unclear which miRNA pairs can synergize and which genes are target of cooperative miRNA regulation. In this paper, we present a computational workflow for the prediction and analysis of cooperating miRNAs and their mutual target genes, which we refer to as RNA triplexes. The workflow integrates methods of miRNA target prediction; triplex structure analysis; molecular dynamics simulations and mathematical modeling for a reliable prediction of functional RNA triplexes and target repression efficiency. In a case study we analyzed the human genome and identified several thousand targets of cooperative gene regulation. Our results suggest that miRNA cooperativity is a frequent mechanism for an enhanced target repression by pairs of miRNAs facilitating distinctive and fine-tuned target gene expression patterns. Human RNA triplexes predicted and characterized in this study are organized in a web resource at www.sbi.uni-rostock.de/triplexrna/.
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Affiliation(s)
- Ulf Schmitz
- Department of Systems Biology and Bioinformatics, University of Rostock, Rostock, Germany
| | - Xin Lai
- Laboratory of Systems Tumor Immunology, Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nuremberg, Germany
| | - Felix Winter
- Department of Systems Biology and Bioinformatics, University of Rostock, Rostock, Germany
| | - Olaf Wolkenhauer
- Department of Systems Biology and Bioinformatics, University of Rostock, Rostock, Germany Stellenbosch Institute for Advanced Study (STIAS), Wallenberg Research Centre at Stellenbosch University, Stellenbosch, South Africa
| | - Julio Vera
- Laboratory of Systems Tumor Immunology, Department of Dermatology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nuremberg, Germany
| | - Shailendra K Gupta
- Department of Systems Biology and Bioinformatics, University of Rostock, Rostock, Germany Department of Bioinformatics, CSIR-Indian Institute of Toxicology Research, 226001 Lucknow, Uttar Pradesh, India
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13
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Afonin KA, Kasprzak W, Bindewald E, Puppala PS, Diehl AR, Hall KT, Kim TJ, Zimmermann MT, Jernigan RL, Jaeger L, Shapiro BA. Computational and experimental characterization of RNA cubic nanoscaffolds. Methods 2014; 67:256-65. [PMID: 24189588 PMCID: PMC4007386 DOI: 10.1016/j.ymeth.2013.10.013] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 10/11/2013] [Accepted: 10/16/2013] [Indexed: 01/03/2023] Open
Abstract
The fast-developing field of RNA nanotechnology requires the adoption and development of novel and faster computational approaches to modeling and characterization of RNA-based nano-objects. We report the first application of Elastic Network Modeling (ENM), a structure-based dynamics model, to RNA nanotechnology. With the use of an Anisotropic Network Model (ANM), a type of ENM, we characterize the dynamic behavior of non-compact, multi-stranded RNA-based nanocubes that can be used as nano-scale scaffolds carrying different functionalities. Modeling the nanocubes with our tool NanoTiler and exploring the dynamic characteristics of the models with ANM suggested relatively minor but important structural modifications that enhanced the assembly properties and thermodynamic stabilities. In silico and in vitro, we compared nanocubes having different numbers of base pairs per side, showing with both methods that the 10 bp-long helix design leads to more efficient assembly, as predicted computationally. We also explored the impact of different numbers of single-stranded nucleotide stretches at each of the cube corners and showed that cube flexibility simulations help explain the differences in the experimental assembly yields, as well as the measured nanomolecule sizes and melting temperatures. This original work paves the way for detailed computational analysis of the dynamic behavior of artificially designed multi-stranded RNA nanoparticles.
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Affiliation(s)
- Kirill A Afonin
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Wojciech Kasprzak
- Basic Science Program, SAIC-Frederick, Inc., Center for Cancer Research Nanobiology Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Eckart Bindewald
- Basic Science Program, SAIC-Frederick, Inc., Center for Cancer Research Nanobiology Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Praneet S Puppala
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Alex R Diehl
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Kenneth T Hall
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Tae Jin Kim
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD 21702, USA
| | - Michael T Zimmermann
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Robert L Jernigan
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Luc Jaeger
- Department of Chemistry and Biochemistry, Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106-9510, USA.
| | - Bruce A Shapiro
- Center for Cancer Research Nanobiology Program, National Cancer Institute, Frederick, MD 21702, USA.
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Qiu M, Khisamutdinov E, Zhao Z, Pan C, Choi JW, Leontis NB, Guo P. RNA nanotechnology for computer design and in vivo computation. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2013; 371:20120310. [PMID: 24000362 PMCID: PMC3758167 DOI: 10.1098/rsta.2012.0310] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Molecular-scale computing has been explored since 1989 owing to the foreseeable limitation of Moore's law for silicon-based computation devices. With the potential of massive parallelism, low energy consumption and capability of working in vivo, molecular-scale computing promises a new computational paradigm. Inspired by the concepts from the electronic computer, DNA computing has realized basic Boolean functions and has progressed into multi-layered circuits. Recently, RNA nanotechnology has emerged as an alternative approach. Owing to the newly discovered thermodynamic stability of a special RNA motif (Shu et al. 2011 Nat. Nanotechnol. 6, 658-667 (doi:10.1038/nnano.2011.105)), RNA nanoparticles are emerging as another promising medium for nanodevice and nanomedicine as well as molecular-scale computing. Like DNA, RNA sequences can be designed to form desired secondary structures in a straightforward manner, but RNA is structurally more versatile and more thermodynamically stable owing to its non-canonical base-pairing, tertiary interactions and base-stacking property. A 90-nucleotide RNA can exhibit 4⁹⁰ nanostructures, and its loops and tertiary architecture can serve as a mounting dovetail that eliminates the need for external linking dowels. Its enzymatic and fluorogenic activity creates diversity in computational design. Varieties of small RNA can work cooperatively, synergistically or antagonistically to carry out computational logic circuits. The riboswitch and enzymatic ribozyme activities and its special in vivo attributes offer a great potential for in vivo computation. Unique features in transcription, termination, self-assembly, self-processing and acid resistance enable in vivo production of RNA nanoparticles that harbour various regulators for intracellular manipulation. With all these advantages, RNA computation is promising, but it is still in its infancy. Many challenges still exist. Collaborations between RNA nanotechnologists and computer scientists are necessary to advance this nascent technology.
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Affiliation(s)
- Meikang Qiu
- Department of Computer Engineering, San Jose State University, San Jose, CA 95192, USA
| | - Emil Khisamutdinov
- Department of Pharmaceutical Science, University of Kentucky, Lexington, KY 40506, USA
| | - Zhengyi Zhao
- Department of Pharmaceutical Science, University of Kentucky, Lexington, KY 40506, USA
| | - Cheryl Pan
- Department of Electrical and Computer Engineering, University of Kentucky, Lexington, KY 40506, USA
| | - Jeong-Woo Choi
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742, Korea
| | - Neocles B. Leontis
- Department of Chemistry, Bowling Green State University, Bowling Green, OH 43403, USA
| | - Peixuan Guo
- Department of Pharmaceutical Science, University of Kentucky, Lexington, KY 40506, USA
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15
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Kim T, Shapiro BA. The role of salt concentration and magnesium binding in HIV-1 subtype-A and subtype-B kissing loop monomer structures. J Biomol Struct Dyn 2012; 31:495-510. [PMID: 22881341 DOI: 10.1080/07391102.2012.706072] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The subtype-B monomers of the human immunodeficiency virus type-1 (HIV-1) have experimentally been shown to dimerize at high salt concentration or in the presence of magnesium, while the dimerization of the subtype-A monomers requires magnesium binding at the G273 or G274 phosphate groups regardless of salt concentration. We used explicit solvent molecular dynamics (MD) simulations to investigate the conformational changes in subtype-A and -B monomers in different salt concentrations, and we found that our MD simulation results are consistent with those of experiments. At low salt concentration, hairpin loop structures of both subtypes were deformed and bases in the hairpin loop were turned inside. At high salt concentrations, the subtype-B monomer maintained the hairpin loop shape and most bases in the hairpin loop pointed out, while the subtype-A monomer showed a severe deformation. We also found that the flanking bases in the subtype-B stabilize the hairpin loop, while the flanking base G273 in the subtype-A caused a significant deformation. However, a bound magnesium ion at the G273 or G274 phosphate groups controlled the behavior of the G273 base and prevented the subtype-A monomer from deformation. We also applied restraints to both subtypes to examine the role of high salt concentration or magnesium binding. While restraints were applied, both subtypes at 0 M salt concentration maintained their shapes. However, when restraints were removed, they deformed significantly. Therefore, we suggest that the dimerization of both subtypes requires the proper conformation of the monomers which is induced by the appropriate salt strength and magnesium ion binding.
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Affiliation(s)
- Taejin Kim
- Center for Cancer Research Nanobiology Program, Frederick National Laboratory for Cancer Research, Frederick , MD 20872, USA
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16
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Afonin KA, Grabow WW, Walker FM, Bindewald E, Dobrovolskaia MA, Shapiro BA, Jaeger L. Design and self-assembly of siRNA-functionalized RNA nanoparticles for use in automated nanomedicine. Nat Protoc 2011; 6:2022-34. [PMID: 22134126 PMCID: PMC3498981 DOI: 10.1038/nprot.2011.418] [Citation(s) in RCA: 151] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Individual genes can be targeted with siRNAs. The use of nucleic acid nanoparticles (NPs) is a convenient method for delivering combinations of specific siRNAs in an organized and programmable manner. We present three assembly protocols to produce two different types of RNA self-assembling functional NPs using processes that are fully automatable. These NPs are engineered based on two complementary nanoscaffold designs (nanoring and nanocube), which serve as carriers of multiple siRNAs. The NPs are functionalized by the extension of up to six scaffold strands with siRNA duplexes. The assembly protocols yield functionalized RNA NPs, and we show that they interact in vitro with human recombinant Dicer to produce siRNAs. Our design strategies allow for fast, economical and easily controlled production of endotoxin-free therapeutic RNA NPs that are suitable for preclinical development.
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Affiliation(s)
- Kirill A Afonin
- Department of Chemistry and Biochemistry, Biomolecular Science and Engineering Program, University of California, Santa Barbara, California, USA
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17
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Shen X, Gu B, Che SA, Zhang FS. Solvent effects on the conformation of DNA dodecamer segment: A simulation study. J Chem Phys 2011; 135:034509. [DOI: 10.1063/1.3610549] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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18
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Shukla GC, Haque F, Tor Y, Wilhelmsson LM, Toulmé JJ, Isambert H, Guo P, Rossi JJ, Tenenbaum SA, Shapiro BA. A boost for the emerging field of RNA nanotechnology. ACS NANO 2011; 5:3405-18. [PMID: 21604810 PMCID: PMC3102291 DOI: 10.1021/nn200989r] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This Nano Focus article highlights recent advances in RNA nanotechnology as presented at the First International Conference of RNA Nanotechnology and Therapeutics, which took place in Cleveland, OH, USA (October 23-25, 2010) ( http://www.eng.uc.edu/nanomedicine/RNA2010/ ), chaired by Peixuan Guo and co-chaired by David Rueda and Scott Tenenbaum. The conference was the first of its kind to bring together more than 30 invited speakers in the frontier of RNA nanotechnology from France, Sweden, South Korea, China, and throughout the United States to discuss RNA nanotechnology and its applications. It provided a platform for researchers from academia, government, and the pharmaceutical industry to share existing knowledge, vision, technology, and challenges in the field and promoted collaborations among researchers interested in advancing this emerging scientific discipline. The meeting covered a range of topics, including biophysical and single-molecule approaches for characterization of RNA nanostructures; structure studies on RNA nanoparticles by chemical or biochemical approaches, computation, prediction, and modeling of RNA nanoparticle structures; methods for the assembly of RNA nanoparticles; chemistry for RNA synthesis, conjugation, and labeling; and application of RNA nanoparticles in therapeutics. A special invited talk on the well-established principles of DNA nanotechnology was arranged to provide models for RNA nanotechnology. An Administrator from National Institutes of Health (NIH) National Cancer Institute (NCI) Alliance for Nanotechnology in Cancer discussed the current nanocancer research directions and future funding opportunities at NCI. As indicated by the feedback received from the invited speakers and the meeting participants, this meeting was extremely successful, exciting, and informative, covering many groundbreaking findings, pioneering ideas, and novel discoveries.
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Affiliation(s)
- Girish C. Shukla
- Center for Gene Regulation in Health and Disease, Department of Biological Sciences, Cleveland State University, Cleveland, Ohio 44115, United States
| | - Farzin Haque
- Nanobiomedical Center, College of Engineering and Applied Science, and College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, United States
| | - Yitzhak Tor
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, California 92093, United States
| | - L. Marcus Wilhelmsson
- Department of Chemical and Biological Engineering/Physical Chemistry, Chalmers University of Technology, Kemivägen 10, SE-412 96 Göteborg, Sweden
| | - Jean-Jacques Toulmé
- Université Bordeaux Segalen, INSERM U869, Bâtiment 3A 1er étage, 33076 Bordeaux Cedex, France
| | - Hervé Isambert
- Institut Curie, Research Division, CNRS UMR 168, 11 rue P. & M. Curie, 75005 Paris, France
| | - Peixuan Guo
- Nanobiomedical Center, College of Engineering and Applied Science, and College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, United States
| | - John J. Rossi
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, California 91010, United States
| | - Scott A. Tenenbaum
- College of Nanoscale Science & Engineering, University at Albany-SUNY, Albany, New York 12203, United States
| | - Bruce A. Shapiro
- Center for Cancer Research Nanobiology Program, National Cancer Institute at Frederick, Frederick, Maryland 21702, United States
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Grabow WW, Zakrevsky P, Afonin KA, Chworos A, Shapiro BA, Jaeger L. Self-assembling RNA nanorings based on RNAI/II inverse kissing complexes. NANO LETTERS 2011; 11:878-87. [PMID: 21229999 PMCID: PMC3036768 DOI: 10.1021/nl104271s] [Citation(s) in RCA: 179] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
RNA is an attractive biopolymer for nanodesign of self-assembling particles for nanobiotechnology and synthetic biology. Here, we experimentally characterize by biochemical and biophysical methods the formation of thermostable and ribonuclease resistant RNA nanorings previously proposed by computational design. High yields of fully programmable nanorings were produced based on several RNAI/IIi kissing complex variants selected for their ability to promote polygon self-assembly. This self-assembly strategy relying on the particular geometry of bended kissing complexes has potential for developing short interfering RNA delivery agents.
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Affiliation(s)
- Wade W. Grabow
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
| | - Paul Zakrevsky
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
| | - Kirill A. Afonin
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
| | - Arkadiusz Chworos
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
| | - Bruce A. Shapiro
- Center for Cancer Research Nanobiology Program, National Cancer Institute, NCI-Frederick, National Institutes of Health, Frederick, Maryland 21702
| | - Luc Jaeger
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA 93106-9510, USA
- Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106, USA
- To whom correspondence should be addressed: Phone: 805-8933628; Fax: 805-8934120;
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Kim T, Barchi JJ, Marquez VE, Shapiro BA. Understanding the effects of carbocyclic sugars constrained to north and south conformations on RNA nanodesign. J Mol Graph Model 2011; 29:624-34. [PMID: 21159533 PMCID: PMC3040123 DOI: 10.1016/j.jmgm.2010.11.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 11/05/2010] [Accepted: 11/10/2010] [Indexed: 11/28/2022]
Abstract
Relatively new types of the modified nucleotides, namely carbocyclic sugars that are constrained to north or south (C2' or C3' exo) conformations, can be used for RNA nanoparticle design to control their structures and stability by rigidifying nucleotides and altering the helical properties of RNA duplexes. Two RNA structures, an RNA dodecamer and an HIV kissing loop complex where several nucleotides were replaced with north or south constrained sugars, were studied by molecular dynamics (MD) simulations. The substituted south constrained nucleotides in the dodecamer widened the major groove and narrowed and deepened the minor groove thus inducing local conformational changes that resemble a B-form DNA helix. In the HIV kissing loop complex, north and south constrained nucleotides were substituted into flanking bases and stems. The modified HIV kissing loop complex showed a lower RMSD value than the normal kissing loop complex. The overall twist angle was also changed and its standard deviation was reduced. In addition, the modified RNA dodecamer and HIV kissing loop complex were characterized by principal component analysis (PCA) and steered molecular dynamics (SMD). PCA results showed that the constrained sugars stabilized the overall motions. The results of the SMD simulations indicated that as the backbone δ angles were increased by elongation, more force was applied to the modified RNA due to the constrained sugar analogues.
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Affiliation(s)
- Taejin Kim
- Center for Cancer Research Nanobiology Program (CCRNP), National Cancer Institute at Frederick, Frederick, MD, USA
| | - Joseph J. Barchi
- Laboratory of Medicinal Chemistry, National Cancer Institute at Frederick, Frederick, MD, USA
| | - Victor E. Marquez
- Laboratory of Medicinal Chemistry, National Cancer Institute at Frederick, Frederick, MD, USA
| | - Bruce A. Shapiro
- Center for Cancer Research Nanobiology Program (CCRNP), National Cancer Institute at Frederick, Frederick, MD, USA
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21
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Abstract
A series of coarse-grained models have been developed for study of the molecular dynamics of RNA nanostructures. The models in the series have one to three beads per nucleotide and include different amounts of detailed structural information. Such a treatment allows us to reach, for systems of thousands of nucleotides, a time scale of microseconds (i.e. by three orders of magnitude longer than in full atomistic modeling) and thus to enable simulations of large RNA polymers in the context of bionanotechnology. We find that the three-beads-per-nucleotide models, described by a set of just a few universal parameters, are able to describe different RNA conformations and are comparable in structural precision to the models where detailed values of the backbone P-C4' dihedrals taken from a reference structure are included. These findings are discussed in the context of RNA conformation classes.
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Affiliation(s)
- Maxim Paliy
- M2NeT Lab, Wilfrid Laurier University 75 University Avenue West Waterloo, ON, N2 L 3C5, Canada.
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