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Zhang Y, Xu Z, Xiao Y, Jiang H, Zuo X, Li X, Fang X. Structural mechanisms for binding and activation of a contact-quenched fluorophore by RhoBAST. Nat Commun 2024; 15:4206. [PMID: 38760339 PMCID: PMC11101630 DOI: 10.1038/s41467-024-48478-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 04/29/2024] [Indexed: 05/19/2024] Open
Abstract
The fluorescent light-up aptamer RhoBAST, which binds and activates the fluorophore-quencher conjugate tetramethylrhodamine-dinitroaniline with high affinity, super high brightness, remarkable photostability, and fast exchange kinetics, exhibits excellent performance in super-resolution RNA imaging. Here we determine the co-crystal structure of RhoBAST in complex with tetramethylrhodamine-dinitroaniline to elucidate the molecular basis for ligand binding and fluorescence activation. The structure exhibits an asymmetric "A"-like architecture for RhoBAST with a semi-open binding pocket harboring the xanthene of tetramethylrhodamine at the tip, while the dinitroaniline quencher stacks over the phenyl of tetramethylrhodamine instead of being fully released. Molecular dynamics simulations show highly heterogeneous conformational ensembles with the contact-but-unstacked fluorophore-quencher conformation for both free and bound tetramethylrhodamine-dinitroaniline being predominant. The simulations also show that, upon RNA binding, the fraction of xanthene-dinitroaniline stacked conformation significantly decreases in free tetramethylrhodamine-dinitroaniline. This highlights the importance of releasing dinitroaniline from xanthene tetramethylrhodamine to unquench the RhoBAST-tetramethylrhodamine-dinitroaniline complex. Using SAXS and ITC, we characterized the magnesium dependency of the folding and binding mode of RhoBAST in solution and indicated its strong structural robustness. The structures and binding modes of relevant fluorescent light-up aptamers are compared, providing mechanistic insights for rational design and optimization of this important fluorescent light-up aptamer-ligand system.
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Affiliation(s)
- Yufan Zhang
- Key Laboratory of RNA Science and Engineering, Institute of Biophysics Chinese Academy of Sciences, Beijing, China
| | - Zhonghe Xu
- Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yu Xiao
- Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China
| | - Haodong Jiang
- Institute of Zoology, Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Xiaobing Zuo
- X-ray Science Division, Argonne National Laboratory, Lemont, IL, USA
| | - Xing Li
- Institute of Zoology, Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China.
| | - Xianyang Fang
- Key Laboratory of RNA Science and Engineering, Institute of Biophysics Chinese Academy of Sciences, Beijing, China.
- Beijing Frontier Research Center for Biological Structure, School of Life Sciences, Tsinghua University, Beijing, China.
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2
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Saha R, Kao WL, Malady B, Heng X, Chen IA. Effect of montmorillonite K10 clay on RNA structure and function. Biophys J 2024; 123:451-463. [PMID: 37924206 PMCID: PMC10912936 DOI: 10.1016/j.bpj.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 09/29/2023] [Accepted: 11/01/2023] [Indexed: 11/06/2023] Open
Abstract
One of the earliest living systems was likely based on RNA ("the RNA world"). Mineral surfaces have been postulated to be an important environment for the prebiotic chemistry of RNA. In addition to adsorbing RNA and thus potentially reducing the chance of parasitic takeover through limited diffusion, minerals have been shown to promote a range of processes related to the emergence of life, including RNA polymerization, peptide bond formation, and self-assembly of vesicles. In addition, self-cleaving ribozymes have been shown to retain activity when adsorbed to the clay mineral montmorillonite. However, simulation studies suggest that adsorption to minerals is likely to interfere with RNA folding and, thus, function. To further evaluate the plausibility of a mineral-adsorbed RNA world, here we studied the effect of the synthetic clay montmorillonite K10 on the malachite green RNA aptamer, including binding of the clay to malachite green and RNA, as well as on the formation of secondary structures in model RNA and DNA oligonucleotides. We evaluated the fluorescence of the aptamer complex, adsorption to the mineral, melting curves, Förster resonance energy transfer interactions, and 1H-NMR signals to study the folding and functionality of these nucleic acids. Our results indicate that while some base pairings are unperturbed, the overall folding and binding of the malachite green aptamer are substantially disrupted by montmorillonite. These findings suggest that minerals would constrain the structures, and possibly the functions, available to an adsorbed RNA world.
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Affiliation(s)
- Ranajay Saha
- Department of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, University of California, Los Angeles, California; Department of Chemistry and Biochemistry, University of California, Santa Barbara, California
| | - Wei-Ling Kao
- Department of Biochemistry, University of Missouri, Columbia, Missouri
| | - Brandon Malady
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California
| | - Xiao Heng
- Department of Biochemistry, University of Missouri, Columbia, Missouri
| | - Irene A Chen
- Department of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, University of California, Los Angeles, California; Department of Chemistry and Biochemistry, University of California, Santa Barbara, California.
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3
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Shchaslyvyi AY, Antonenko SV, Tesliuk MG, Telegeev GD. Current State of Human Gene Therapy: Approved Products and Vectors. Pharmaceuticals (Basel) 2023; 16:1416. [PMID: 37895887 PMCID: PMC10609992 DOI: 10.3390/ph16101416] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/13/2023] [Accepted: 09/19/2023] [Indexed: 10/29/2023] Open
Abstract
In the realm of gene therapy, a pivotal moment arrived with Paul Berg's groundbreaking identification of the first recombinant DNA in 1972. This achievement set the stage for future breakthroughs. Conditions once considered undefeatable, like melanoma, pancreatic cancer, and a host of other ailments, are now being addressed at their root cause-the genetic level. Presently, the gene therapy landscape stands adorned with 22 approved in vivo and ex vivo products, including IMLYGIC, LUXTURNA, Zolgensma, Spinraza, Patisiran, and many more. In this comprehensive exploration, we delve into a rich assortment of 16 drugs, from siRNA, miRNA, and CRISPR/Cas9 to DNA aptamers and TRAIL/APO2L, as well as 46 carriers, from AAV, AdV, LNPs, and exosomes to naked mRNA, sonoporation, and magnetofection. The article also discusses the advantages and disadvantages of each product and vector type, as well as the current challenges faced in the practical use of gene therapy and its future potential.
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Affiliation(s)
- Aladdin Y. Shchaslyvyi
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150, Zabolotnogo Str., 03143 Kyiv, Ukraine; (S.V.A.); (M.G.T.); (G.D.T.)
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4
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Chen Z, Chen W, Reheman Z, Jiang H, Wu J, Li X. Genetically encoded RNA-based sensors with Pepper fluorogenic aptamer. Nucleic Acids Res 2023; 51:8322-8336. [PMID: 37486780 PMCID: PMC10484673 DOI: 10.1093/nar/gkad620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 07/21/2023] [Indexed: 07/26/2023] Open
Abstract
Sensors to measure the abundance and signaling of intracellular molecules are crucial for understanding their physiological functions. Although conventional fluorescent protein-based sensors have been designed, RNA-based sensors are promising imaging tools. Numerous RNA-based sensors have been developed. These sensors typically contain RNA G-quadruplex (RG4) motifs and thus may be suboptimal in living cells. Here we describe RNA-based sensors based on Pepper, a fluorogenic RNA without an RG4 motif. With Pepper, we engineered various sensors for metabolites, synthetic compounds, proteins and metal ions in vitro and in living cells. In addition, these sensors show high activation and selectivity, demonstrating their universality and robustness. In the case of sensors responding to S-adenosylmethionine (SAM), a metabolite produced by methionine adenosyltransferase (MATase), we showed that our sensors exhibited positively correlated fluorescence responding to different SAM levels. Importantly, we revealed the SAM biosynthesis pathway and monitored MATase activity and gene expression spatiotemporally in living individual human cells. Additionally, we constructed a ratiometric SAM sensor to determine the inhibition efficacy of a MATase inhibitor in living cells. Together, these sensors comprising Pepper provide a useful platform for imaging diverse cellular targets and their signaling pathway.
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Affiliation(s)
- Zhenyin Chen
- Beijing Institute of Life Sciences, Chinese Academy of Sciences, Beijing 100101, China
- Department of Pulmonary and Critical Care Medicine, Department of Inflammation and Clinical Allergology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Chen
- Beijing Institute of Life Sciences, Chinese Academy of Sciences, Beijing 100101, China
- Institute of Cytology and Genetics, the Hengyang Key Laboratory of Cellular Stress Biology, Hengyang Medical School, University of South China, Hengyang, Hunan 421001, China
| | - Zhayila Reheman
- Beijing Institute of Life Sciences, Chinese Academy of Sciences, Beijing 100101, China
- School of Life Science, Hebei University, Baoding, Hebei 071000, China
| | - Haodong Jiang
- Beijing Institute of Life Sciences, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiahui Wu
- Department of Chemistry, University of Massachusetts, Amherst, MA01003, USA
| | - Xing Li
- Beijing Institute of Life Sciences, Chinese Academy of Sciences, Beijing 100101, China
- Department of Pulmonary and Critical Care Medicine, Department of Inflammation and Clinical Allergology, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan 646000, China
- Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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5
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Chen K, Zhu L, Du Z, Lan X, Huang K, Zhang W, Xu W. Docking-aided rational tailoring of a fluorescence- and affinity-enhancing aptamer for a label-free ratiometric malachite green point-of-care aptasensor. JOURNAL OF HAZARDOUS MATERIALS 2023; 447:130798. [PMID: 36669418 DOI: 10.1016/j.jhazmat.2023.130798] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 06/17/2023]
Abstract
Although nucleic acid aptasensors are increasingly applied in the detection of environmentally hazardous biomolecules, several formidable challenges remain with this technique because of their vulnerability, high cost and suboptimal sensitivity. Here, a docking-aided rational tailoring (DART) strategy was established at three levels and in two dimensions for the refinement of malachite green (MG) DNA aptamers. Guided by in silico molecular docking, coarse and fine tailoring were conducted at three levels each, to significantly enhance fluorescence activation intensity and binding affinity in two dimensions. Empowered by the results of the rational tailoring, a mechanistic view of the MG DNA aptamer-target interaction was thoroughly analyzed via four types of interactions. To meet the demand for point-of-care testing (POCT), a label-free and ratiometric fluorescent aptasensor was developed leveraging the tailored MG aptamer, based on the binding site competition-equilibrium effect via the introduction of a reference dye. This sensitive, specific, low-cost and rapid aptasensor subsequently demonstrated outstanding detection performance, achieving an ideal signal response range of 5 nmol·L-1 - 6 μmol·L-1 and a low limit of detection (LOD) of 1.49 nmol·L-1. The DART strategy and systematic exploration of the MG DNA luminescent aptamers herein will provide a valuable reference in the field of aptamer tailoring, biosensing and bioimaging. The proposed label-free ratiometric aptasensor also provides a highly generalizable strategy for hazardous biomolecular detection.
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Affiliation(s)
- Keren Chen
- Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Longjiao Zhu
- Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China
| | - Zaihui Du
- Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Xinyue Lan
- Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Kunlun Huang
- Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Wenqiang Zhang
- Department of Mechanical Design and Manufacturing, College of Engineering, China Agricultural University, Beijing 100083, China
| | - Wentao Xu
- Food Laboratory of Zhongyuan, Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100193, China; Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
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6
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Werner A. Translational and rotational diffusion of short ribonucleic acids. Biochem Biophys Res Commun 2023; 650:17-20. [PMID: 36764208 DOI: 10.1016/j.bbrc.2023.01.028] [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: 12/27/2022] [Revised: 01/11/2023] [Accepted: 01/11/2023] [Indexed: 02/05/2023]
Abstract
Inevitable precondition for ribonucleic acids to regulate gene expression and to perform gene editing is diffusion. Free three-dimensional translational diffusion velocity of RNA of up to 200 nucleotides could be predicted with high accuracy by the empirical model D = 4.58 10-10 N-0.39 m2s-1. Furthermore, the biological function of ribonucleic acids is determined by rotational diffusion. In the presented work, an empirical model is derived applying atom-level shell-modeling of electron density maps, Dr = 1.62 109 N-1.20 s-1, to predict the rotational diffusion coefficient of short ribonucleic acids based on the polymer size.
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Affiliation(s)
- Arne Werner
- Institute for Biochemistry and Molecular Biology, Department of Chemistry, Faculty of Mathematics, Computer Science and Natural Science, Hamburg University, Germany.
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7
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Morishita EC. Discovery of RNA-targeted small molecules through the merging of experimental and computational technologies. Expert Opin Drug Discov 2023; 18:207-226. [PMID: 36322542 DOI: 10.1080/17460441.2022.2134852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION The field of RNA-targeted small molecules is rapidly evolving, owing to the advances in experimental and computational technologies. With the identification of several bioactive small molecules that target RNA, including the FDA-approved risdiplam, the biopharmaceutical industry is gaining confidence in the field. This review, based on the literature obtained from PubMed, aims to disseminate information about the various technologies developed for targeting RNA with small molecules and propose areas for improvement to develop drugs more efficiently, particularly those linked to diseases with unmet medical needs. AREAS COVERED The technologies for the identification of RNA targets, screening of chemical libraries against RNA, assessing the bioactivity and target engagement of the hit compounds, structure determination, and hit-to-lead optimization are reviewed. Along with the description of the technologies, their strengths, limitations, and examples of how they can impact drug discovery are provided. EXPERT OPINION Many existing technologies employed for protein targets have been repurposed for use in the discovery of RNA-targeted small molecules. In addition, technologies tailored for RNA targets have been developed. Nevertheless, more improvements are necessary, such as artificial intelligence to dissect important RNA structures and RNA-small-molecule interactions and more powerful chemical probing and structure prediction techniques.
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8
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Dong X, Qi S, Khan IM, Sun Y, Zhang Y, Wang Z. Advances in riboswitch-based biosensor as food samples detection tool. Compr Rev Food Sci Food Saf 2023; 22:451-472. [PMID: 36511082 DOI: 10.1111/1541-4337.13077] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 10/09/2022] [Accepted: 10/25/2022] [Indexed: 12/14/2022]
Abstract
Food safety has always been a hot issue of social concern, and biosensing has been widely used in the field of food safety detection. Compared with traditional aptamer-based biosensors, aptamer-based riboswitch biosensing represents higher precision and programmability. A riboswitch is an elegant example of controlling gene expression, where the target is coupled to the aptamer domain, resulting in a conformational change in the downstream expression domain and determining the signal output. Riboswitch-based biosensing can be extensively applied to the portable real-time detection of food samples. The numerous key features of riboswitch-based biosensing emphasize their sustainability, renewable, and testing, which promises to transform engineering applications in the field of food safety. This review covers recent developments in riboswitch-based biosensors. The brief history, definition, and modular design (regulatory mode, reporter, and expression platform) of riboswitch-based biosensors are explained for better insight into the design and construction. We summarize recent advances in various riboswitch-based biosensors involving theophylline, malachite green, tetracycline, neomycin, fluoride, thrombin, naringenin, ciprofloxacin, and paromomycin, aiming to provide general guidance for the design of riboswitch-based biosensors. Finally, the challenges and prospects are also summarized as a way forward stratagem and signs of progress.
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Affiliation(s)
- Xiaoze Dong
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Shuo Qi
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Imran Mahmood Khan
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Yuhan Sun
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Yin Zhang
- Key Laboratory of Meat Processing of Sichuan, Chengdu University, Chengdu, China
| | - Zhouping Wang
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China.,School of Food Science and Technology, Jiangnan University, Wuxi, China.,Key Laboratory of Meat Processing of Sichuan, Chengdu University, Chengdu, China.,National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, China.,Collaborative innovation center of food safety and quality control in Jiangsu Province, Food, Jiangnan University, Wuxi, China
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9
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Maloshenok LG, Abushinova GA, Ryazanova AY, Bruskin SA, Zherdeva VV. Visualizing the Nucleome Using the CRISPR–Cas9 System: From in vitro to in vivo. BIOCHEMISTRY (MOSCOW) 2023; 88:S123-S149. [PMID: 37069118 PMCID: PMC9940691 DOI: 10.1134/s0006297923140080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
One of the latest methods in modern molecular biology is labeling genomic loci in living cells using fluorescently labeled Cas protein. The NIH Foundation has made the mapping of the 4D nucleome (the three-dimensional nucleome on a timescale) a priority in the studies aimed to improve our understanding of chromatin organization. Fluorescent methods based on CRISPR-Cas are a significant step forward in visualization of genomic loci in living cells. This approach can be used for studying epigenetics, cell cycle, cellular response to external stimuli, rearrangements during malignant cell transformation, such as chromosomal translocations or damage, as well as for genome editing. In this review, we focused on the application of CRISPR-Cas fluorescence technologies as components of multimodal imaging methods for in vivo mapping of chromosomal loci, in particular, attribution of fluorescence signal to morphological and anatomical structures in a living organism. The review discusses the approaches to the highly sensitive, high-precision labeling of CRISPR-Cas components, delivery of genetically engineered constructs into cells and tissues, and promising methods for molecular imaging.
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Affiliation(s)
- Liliya G Maloshenok
- Bach Institute of Biochemistry, Federal Research Center for Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Gerel A Abushinova
- Bach Institute of Biochemistry, Federal Research Center for Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Alexandra Yu Ryazanova
- Bach Institute of Biochemistry, Federal Research Center for Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia
| | - Sergey A Bruskin
- Bach Institute of Biochemistry, Federal Research Center for Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia
- Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, 119991, Russia
| | - Victoria V Zherdeva
- Bach Institute of Biochemistry, Federal Research Center for Biotechnology of the Russian Academy of Sciences, Moscow, 119071, Russia.
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10
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Recent advance of RNA aptamers and DNAzymes for MicroRNA detection. Biosens Bioelectron 2022; 212:114423. [DOI: 10.1016/j.bios.2022.114423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2022] [Revised: 04/19/2022] [Accepted: 05/23/2022] [Indexed: 02/02/2023]
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Rees HC, Gogacz W, Li NS, Koirala D, Piccirilli JA. Structural Basis for Fluorescence Activation by Pepper RNA. ACS Chem Biol 2022; 17:1866-1875. [PMID: 35759696 PMCID: PMC9969808 DOI: 10.1021/acschembio.2c00290] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pepper is a fluorogenic RNA aptamer tag that binds to a variety of benzylidene-cyanophenyl (HBC) derivatives with tight affinity and activates their fluorescence. To investigate how Pepper RNA folds to create a binding site for HBC, we used antibody-assisted crystallography to determine the structures of Pepper bound to HBC530 and HBC599 to 2.3 and 2.7 Å resolutions, respectively. The structural data show that Pepper folds into an elongated structure and organizes nucleotides within an internal bulge to create the ligand binding site, assisted by an out-of-plane platform created by tertiary interactions with an adjacent bulge. As predicted from a lack of K+ dependence, Pepper does not use a G-quadruplex to form a binding pocket for HBC. Instead, Pepper uses a unique base-quadruple·base-triple stack to sandwich the ligand with a U·G wobble pair. Site-bound Mg2+ ions support ligand binding structurally and energetically. This research provides insight into the structural features that allow the Pepper aptamer to bind HBC and show how Pepper's function may expand to allow the in vivo detection of other small molecules and metals.
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Affiliation(s)
- Huw C. Rees
- Department of Chemistry, University of Chicago, Chicago, Illinois, 60637, United States
| | - Wojciech Gogacz
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, 60637, United States
| | - Nan-Sheng Li
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, 60637, United States
| | - Deepak Koirala
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, 60637, United States
| | - Joseph A. Piccirilli
- Department of Chemistry, University of Chicago, Chicago, Illinois, 60637, United States,Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, 60637, United States,corresponding author
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Crowdsourced RNA design discovers diverse, reversible, efficient, self-contained molecular switches. Proc Natl Acad Sci U S A 2022; 119:e2112979119. [PMID: 35471911 PMCID: PMC9170038 DOI: 10.1073/pnas.2112979119] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Internet-based scientific communities promise a means to apply distributed, diverse human intelligence toward previously intractable scientific problems. However, current implementations have not allowed communities to propose experiments to test all emerging hypotheses at scale or to modify hypotheses in response to experiments. We report high-throughput methods for molecular characterization of nucleic acids that enable the large-scale video game–based crowdsourcing of RNA sensor design, followed by high-throughput functional characterization. Iterative design testing of thousands of crowdsourced RNA sensor designs produced near–thermodynamically optimal and reversible RNA switches that act as self-contained molecular sensors and couple five distinct small molecule inputs to three distinct protein binding and fluorogenic outputs. This work suggests a paradigm for widely distributed experimental bioscience.
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Qian S, Chang D, He S, Li Y. Aptamers from random sequence space: Accomplishments, gaps and future considerations. Anal Chim Acta 2022; 1196:339511. [DOI: 10.1016/j.aca.2022.339511] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 01/12/2022] [Accepted: 01/15/2022] [Indexed: 02/07/2023]
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14
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The fluorescent aptamer Squash extensively repurposes the adenine riboswitch fold. Nat Chem Biol 2022; 18:191-198. [PMID: 34937911 PMCID: PMC9812287 DOI: 10.1038/s41589-021-00931-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 10/21/2021] [Indexed: 01/07/2023]
Abstract
Squash is an RNA aptamer that strongly activates the fluorescence of small-molecule analogs of the fluorophore of green fluorescent protein (GFP). Unlike other fluorogenic aptamers, isolated de novo from random-sequence RNA, Squash was evolved from the bacterial adenine riboswitch to leverage its optimized in vivo folding and stability. We now report the 2.7-Å resolution cocrystal structure of fluorophore-bound Squash, revealing that while the overall fold of the riboswitch is preserved, the architecture of the ligand-binding core is dramatically transformed. Unlike previously characterized aptamers that activate GFP-derived fluorophores, Squash does not harbor a G-quadruplex, sandwiching its fluorophore between a base triple and a noncanonical base quadruple in a largely apolar pocket. The expanded structural core of Squash allows it to recognize unnatural fluorophores that are larger than the simple purine ligand of the parental adenine riboswitch, and suggests that stable RNA scaffolds can tolerate larger variation than has hitherto been appreciated.
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15
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Kim DH, Seo JM, Shin KJ, Yang SG. Design and clinical developments of aptamer-drug conjugates for targeted cancer therapy. Biomater Res 2021; 25:42. [PMID: 34823601 PMCID: PMC8613924 DOI: 10.1186/s40824-021-00244-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/09/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Aptamer has been called "chemical antibody" which displays the specific affinity to target molecules compared to that of antibodies and possesses several therapeutic advantages over antibodies in terms of size, accessibility to synthesis, and modification. Based on the attractive properties, aptamers have been interested in many directions and now are emerged as new target-designed cancer drug. MAIN BODY Currently, new types of aptamers have been reported and attracted many scientists' interesting. Due to simplicity of chemical modification and ready-made molecular engineering, scientists have developed newly designed aptamers conjugated with a wide range of therapeutics, aptamer-drug conjugates; ApDCs, from chemotherapy to phototherapy, gene therapy, and vaccines. ApDCs display synergistic therapeutic effects in cancer treatment. CONCLUSION In this paper, we reviewed various kinds of ApDCs, i.e., ApDC nucleotide analogs, ApDC by drug intercalation, and ApDC by using chemical linker. Current data prove these ApDCs have sufficient potential to complete clinical development soon. Advanced technology of cancer drug delivery and combination treatment of cancers enables aptamer and conjugated drug (ApDCs) efficient means for targeted cancer treatment that reduces potential toxicity and increases therapeutic efficacy.
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Affiliation(s)
- Do-Hun Kim
- Department of Biomedical Science, BK21 FOUR Program in Biomedical Science and Engineering, Inha University College of Medicine, Incheon, 22212, South Korea.,Inha Institute of Aerospace Medicine, Inha University College of Medicine, Incheon, 22332, South Korea
| | - Jin-Myung Seo
- Department of Biomedical Science, BK21 FOUR Program in Biomedical Science and Engineering, Inha University College of Medicine, Incheon, 22212, South Korea.,Inha Institute of Aerospace Medicine, Inha University College of Medicine, Incheon, 22332, South Korea
| | - Kyung-Ju Shin
- Department of Biomedical Science, BK21 FOUR Program in Biomedical Science and Engineering, Inha University College of Medicine, Incheon, 22212, South Korea
| | - Su-Geun Yang
- Department of Biomedical Science, BK21 FOUR Program in Biomedical Science and Engineering, Inha University College of Medicine, Incheon, 22212, South Korea. .,Inha Institute of Aerospace Medicine, Inha University College of Medicine, Incheon, 22332, South Korea.
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16
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Fluorescent functional nucleic acid: Principles, properties and applications in bioanalyzing. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116292] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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17
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Truong JQ, Nguyen S, Bruning JB, Shearwin KE. Simplified heavy-atom derivatization of protein structures via co-crystallization with the MAD tetragon tetrabromoterephthalic acid. Acta Crystallogr F Struct Biol Commun 2021; 77:156-162. [PMID: 33949976 PMCID: PMC8098126 DOI: 10.1107/s2053230x21004052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/15/2021] [Indexed: 11/10/2022] Open
Abstract
The phase problem is a persistent bottleneck that impedes the structure-determination pipeline and must be solved to obtain atomic resolution crystal structures of macromolecules. Although molecular replacement has become the predominant method of solving the phase problem, many scenarios still exist in which experimental phasing is needed. Here, a proof-of-concept study is presented that shows the efficacy of using tetrabromoterephthalic acid (B4C) as an experimental phasing compound. Incorporating B4C into the crystal lattice using co-crystallization, the crystal structure of hen egg-white lysozyme was solved using MAD phasing. The strong anomalous signal generated by its four Br atoms coupled with its compatibility with commonly used crystallization reagents render B4C an effective experimental phasing compound that can be used to overcome the phase problem.
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Affiliation(s)
- Jia Q. Truong
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Stephanie Nguyen
- Institute of Photonics and Advanced Sensing (IPAS), School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - John B. Bruning
- Institute of Photonics and Advanced Sensing (IPAS), School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Keith E. Shearwin
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
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18
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A malachite green light-up aptasensor for the detection of theophylline. Talanta 2021; 232:122417. [PMID: 34074405 DOI: 10.1016/j.talanta.2021.122417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 04/01/2021] [Accepted: 04/08/2021] [Indexed: 11/24/2022]
Abstract
Biosensors are of interest for the quantitative detection of small molecules (metabolites, drugs and contaminants for instance). To this end, fluorescence is a widely used technique that is easily associated to aptamers. Light-up aptamers constitute a particular class of oligonucleotides that, specifically induce fluorescence emission when binding to cognate fluorogenic ligands such as malachite green (MG). We engineered a dual aptasensor for theophylline (Th) based on the combination of switching hairpin aptamers specific for MG on the one hand and for Th on the other hand, hence their names: malaswitch (Msw) and theoswitch (Thsw). The two aptaswitches form a loop-loop or kissing Msw-Thsw complex only in the presence of theophylline, allowing binding of MG, subsequently generating a fluorescent signal. The combination of the best Msw and Thsw variants, MswG12 and Thsw19.1, results in a 20-fold fluorescence enhancement of MG at saturating theophylline concentration. This aptasensor discriminates between theophylline and its analogues caffeine and theobromine. Kissing aptaswitches derived from light-up aptamers constitute a novel sensing device.
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19
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Abstract
Technologies for RNA imaging in live cells play an important role in understanding the function and regulatory process of RNAs. One approach for genetically encoded fluorescent RNA imaging involves fluorescent light-up aptamers (FLAPs), which are short RNA sequences that can bind cognate fluorogens and activate their fluorescence greatly. Over the past few years, FLAPs have emerged as genetically encoded RNA-based fluorescent biosensors for the cellular imaging and detection of various targets of interest. In this review, we first give a brief overview of the development of the current FLAPs based on various fluorogens. Then we further discuss on the photocycles of the reversibly photoswitching properties in FLAPs and their photostability. Finally, we focus on the applications of FLAPs as genetically encoded RNA-based fluorescent biosensors in biosensing and bioimaging, including RNA, non-nucleic acid molecules, metal ions imaging and quantitative imaging. Their design strategies and recent cellular applications are emphasized and summarized in detail.
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Affiliation(s)
- Huangmei Zhou
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China
| | - Sanjun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai, China.,Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan, Shanxi, China.,NYU-ECNU Institute of Physics at NYU Shanghai, Shanghai, China
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20
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Ryckelynck M. Development and Applications of Fluorogen/Light-Up RNA Aptamer Pairs for RNA Detection and More. Methods Mol Biol 2021; 2166:73-102. [PMID: 32710404 DOI: 10.1007/978-1-0716-0712-1_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The central role of RNA in living systems made it highly desirable to have noninvasive and sensitive technologies allowing for imaging the synthesis and the location of these molecules in living cells. This need motivated the development of small pro-fluorescent molecules called "fluorogens" that become fluorescent upon binding to genetically encodable RNAs called "light-up aptamers." Yet, the development of these fluorogen/light-up RNA pairs is a long and thorough process starting with the careful design of the fluorogen and pursued by the selection of a specific and efficient synthetic aptamer. This chapter summarizes the main design and the selection strategies used up to now prior to introducing the main pairs. Then, the vast application potential of these molecules for live-cell RNA imaging and other applications is presented and discussed.
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Affiliation(s)
- Michael Ryckelynck
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France.
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21
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An RNA-centric historical narrative around the Protein Data Bank. J Biol Chem 2021; 296:100555. [PMID: 33744291 PMCID: PMC8080527 DOI: 10.1016/j.jbc.2021.100555] [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: 11/05/2020] [Revised: 02/17/2021] [Accepted: 03/16/2021] [Indexed: 01/06/2023] Open
Abstract
Some of the amazing contributions brought to the scientific community by the Protein Data Bank (PDB) are described. The focus is on nucleic acid structures with a bias toward RNA. The evolution and key roles in science of the PDB and other structural databases for nucleic acids illustrate how small initial ideas can become huge and indispensable resources with the unflinching willingness of scientists to cooperate globally. The progress in the understanding of the molecular interactions driving RNA architectures followed the rapid increase in RNA structures in the PDB. That increase was consecutive to improvements in chemical synthesis and purification of RNA molecules, as well as in biophysical methods for structure determination and computer technology. The RNA modeling efforts from the early beginnings are also described together with their links to the state of structural knowledge and technological development. Structures of RNA and of its assemblies are physical objects, which, together with genomic data, allow us to integrate present-day biological functions and the historical evolution in all living species on earth.
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22
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Shanaa OA, Rumyantsev A, Sambuk E, Padkina M. In Vivo Production of RNA Aptamers and Nanoparticles: Problems and Prospects. Molecules 2021; 26:molecules26051422. [PMID: 33800717 PMCID: PMC7961669 DOI: 10.3390/molecules26051422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 03/04/2021] [Accepted: 03/04/2021] [Indexed: 12/26/2022] Open
Abstract
RNA aptamers are becoming increasingly attractive due to their superior properties. This review discusses the early stages of aptamer research, the main developments in this area, and the latest technologies being developed. The review also highlights the advantages of RNA aptamers in comparison to antibodies, considering the great potential of RNA aptamers and their applications in the near future. In addition, it is shown how RNA aptamers can form endless 3-D structures, giving rise to various structural and functional possibilities. Special attention is paid to the Mango, Spinach and Broccoli fluorescent RNA aptamers, and the advantages of split RNA aptamers are discussed. The review focuses on the importance of creating a platform for the synthesis of RNA nanoparticles in vivo and examines yeast, namely Saccharomyces cerevisiae, as a potential model organism for the production of RNA nanoparticles on a large scale.
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Affiliation(s)
- Ousama Al Shanaa
- Department of Genetics and Biotechnology, Saint Petersburg State University, 199034 Saint Petersburg, Russia; (A.R.); (E.S.)
- Atomic Energy Commission of Syria, Damascus P.O.B 6091, Syria
- Correspondence: (O.A.S.); (M.P.); Tel.: +7-812-328-2822 (O.A.S.); +7-812-327-9827 (M.P.)
| | - Andrey Rumyantsev
- Department of Genetics and Biotechnology, Saint Petersburg State University, 199034 Saint Petersburg, Russia; (A.R.); (E.S.)
| | - Elena Sambuk
- Department of Genetics and Biotechnology, Saint Petersburg State University, 199034 Saint Petersburg, Russia; (A.R.); (E.S.)
| | - Marina Padkina
- Department of Genetics and Biotechnology, Saint Petersburg State University, 199034 Saint Petersburg, Russia; (A.R.); (E.S.)
- Correspondence: (O.A.S.); (M.P.); Tel.: +7-812-328-2822 (O.A.S.); +7-812-327-9827 (M.P.)
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23
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Swetha P, Fan Z, Wang F, Jiang JH. Genetically encoded light-up RNA aptamers and their applications for imaging and biosensing. J Mater Chem B 2021; 8:3382-3392. [PMID: 31984401 DOI: 10.1039/c9tb02668a] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Intracellular small ligands and biomacromolecules are playing crucial roles not only as executors but also as regulators. It is essential to develop tools to investigate their dynamics to interrogate their functions and reflect the cellular status. Light-up RNA aptamers are RNA sequences that can bind with their cognate nonfluorescent fluorogens and greatly activate their fluorescence. The emergence of genetically encoded light-up RNA aptamers has provided fascinating tools for studying intracellular small ligands and biomacromolecules owing to their high fluorescence activation degree and facile programmability. Here we review the burgeoning field of light-up RNA aptamers. We first briefly introduce light-up RNA aptamers with a focus on the photophysical properties of the fluorogens. Then design strategies of genetically encoded light-up RNA aptamer based sensors including turn-on, signal amplification and ratiometric rationales are emphasized.
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Affiliation(s)
- Puchakayala Swetha
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hu-nan University, Changsha, 410082, P. R. China.
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24
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Yang H, Eremeeva E, Abramov M, Herdewijn P. The Network of Replication, Transcription, and Reverse Transcription of a Synthetic Genetic Cassette. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202011887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Hui Yang
- Medicinal Chemistry Rega Institute for Medical Research KU Leuven Herestraat 49, Box-1041 3000 Leuven Belgium
| | - Elena Eremeeva
- Medicinal Chemistry Rega Institute for Medical Research KU Leuven Herestraat 49, Box-1041 3000 Leuven Belgium
| | - Mikhail Abramov
- Medicinal Chemistry Rega Institute for Medical Research KU Leuven Herestraat 49, Box-1041 3000 Leuven Belgium
| | - Piet Herdewijn
- Medicinal Chemistry Rega Institute for Medical Research KU Leuven Herestraat 49, Box-1041 3000 Leuven Belgium
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25
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Al Mazid MF, Shkel O, Kharkivska Y, Lee JS. Application of fluorescent turn-on aptamers in RNA studies. Mol Omics 2021; 17:483-491. [PMID: 34137415 DOI: 10.1039/d1mo00085c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
RNA is an intermediate player between DNA transcription and protein translation. RNAs also interact with other macromolecules and metabolites and regulate their fate. The emerging number of RNA identifications expanded new areas of study to determine their applicability and functional analysis. Recently, extensive research has been focused on visualizing RNA in living biological samples and a method has been developed by the evolution of specific fluorophore-binding aptamers through the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) method. Several promising fluorescent turn-on aptamers are currently available, and they can detect RNA-RNA, RNA-protein, ligand binding, small molecule, and metabolite interactions in vitro and under live-cell conditions. Here we review the currently available fluorescent turn-on aptamers and discuss their applicability for analyzing the fate of targeted RNAs in in vitro and in vivo systems.
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Affiliation(s)
| | - Olha Shkel
- Bio-Med Program KIST-School UST, Seoul, 02792, Republic of Korea
| | | | - Jun-Seok Lee
- Department of Pharmacology, Korea University College of Medicine, Seoul, 02841, Republic of Korea.
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26
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Feng Y, Huang SY. ITScore-NL: An Iterative Knowledge-Based Scoring Function for Nucleic Acid-Ligand Interactions. J Chem Inf Model 2020; 60:6698-6708. [PMID: 33291885 DOI: 10.1021/acs.jcim.0c00974] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nucleic acid-ligand complexes underlie numerous cellular processes, such as gene function expression and regulation, in which their three-dimensional structures are important to understand their functions and thus to develop therapeutic interventions. Given the high cost and technical difficulties in experimental methods, computational methods such as molecular docking have been actively used to investigate nucleic acid-ligand interactions in which an accurate scoring function is crucial. However, because of the limited number of experimental nucleic acid-ligand binding data and structures, the scoring function development for nucleic acid-ligand interactions falls far behind that for protein-protein and protein-ligand interactions. Here, based on our statistical mechanics-based iterative approach, we have developed an iterative knowledge-based scoring function for nucleic acid-ligand interactions, named as ITScore-NL, by explicitly including stacking and electrostatic potentials. Our ITScore-NL scoring function was extensively evaluated for its ability in the binding mode and binding affinity predictions on three diverse test sets and compared with state-of-the-art scoring functions. Overall, ITScore-NL obtained significantly better performance than the other 12 scoring functions and predicted near-native poses with rmsd ≤ 1.5 Å for 71.43% of the cases when the top three binding modes were considered and a good correlation of R = 0.64 in binding affinity prediction on the large test set of 77 nucleic acid-ligand complexes. These results suggested the accuracy of ITScore-NL and the necessity of explicitly including stacking and electrostatic potentials.
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Affiliation(s)
- Yuyu Feng
- School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China
| | - Sheng-You Huang
- School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, P. R. China
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27
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Yang H, Eremeeva E, Abramov M, Herdewijn P. The Network of Replication, Transcription, and Reverse Transcription of a Synthetic Genetic Cassette. Angew Chem Int Ed Engl 2020; 60:4175-4182. [PMID: 33142013 DOI: 10.1002/anie.202011887] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/27/2020] [Indexed: 11/07/2022]
Abstract
Synthetic nucleic acids, with four non-canonical nucleobases, can function as genetic materials. A comprehensive analysis of PCR amplification, transcription, reverse transcription, and cloning was done to screen for alternative genetic monomers. A small library of six modified nucleobases was selected: the modified 2'-deoxyribonucleoside (dZTPs) and ribonucleoside (rZTPs) triphosphates of 7-deaza-adenine, 5-chlorouracil, 7-deaza-guanine or inosine together with 5-fluorocytosine or 5-bromocytosine. The fragments composed of one to four modified nucleotides (denoted as DZA) have been successfully recognized and transcribed to natural or modified RNA (denoted as RZA) by T7 RNA polymerase. The fully modified RZA fragment could be reverse transcribed and then amplified in the presence of various dZTPs. Noticeably, modified fragments could function as genetic templates in vivo by encoding the 678 base pair gene of a fluorescent protein in bacteria. These results demonstrate the existence of a fully simulated genetic circuit that uses synthetic materials.
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Affiliation(s)
- Hui Yang
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, Box-1041, 3000, Leuven, Belgium
| | - Elena Eremeeva
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, Box-1041, 3000, Leuven, Belgium
| | - Mikhail Abramov
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, Box-1041, 3000, Leuven, Belgium
| | - Piet Herdewijn
- Medicinal Chemistry, Rega Institute for Medical Research, KU Leuven, Herestraat 49, Box-1041, 3000, Leuven, Belgium
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28
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Micura R, Höbartner C. Fundamental studies of functional nucleic acids: aptamers, riboswitches, ribozymes and DNAzymes. Chem Soc Rev 2020; 49:7331-7353. [PMID: 32944725 DOI: 10.1039/d0cs00617c] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This review aims at juxtaposing common versus distinct structural and functional strategies that are applied by aptamers, riboswitches, and ribozymes/DNAzymes. Focusing on recently discovered systems, we begin our analysis with small-molecule binding aptamers, with emphasis on in vitro-selected fluorogenic RNA aptamers and their different modes of ligand binding and fluorescence activation. Fundamental insights are much needed to advance RNA imaging probes for detection of exo- and endogenous RNA and for RNA process tracking. Secondly, we discuss the latest gene expression-regulating mRNA riboswitches that respond to the alarmone ppGpp, to PRPP, to NAD+, to adenosine and cytidine diphosphates, and to precursors of thiamine biosynthesis (HMP-PP), and we outline new subclasses of SAM and tetrahydrofolate-binding RNA regulators. Many riboswitches bind protein enzyme cofactors that, in principle, can catalyse a chemical reaction. For RNA, however, only one system (glmS ribozyme) has been identified in Nature thus far that utilizes a small molecule - glucosamine-6-phosphate - to participate directly in reaction catalysis (phosphodiester cleavage). We wonder why that is the case and what is to be done to reveal such likely existing cellular activities that could be more diverse than currently imagined. Thirdly, this brings us to the four latest small nucleolytic ribozymes termed twister, twister-sister, pistol, and hatchet as well as to in vitro selected DNA and RNA enzymes that promote new chemistry, mainly by exploiting their ability for RNA labelling and nucleoside modification recognition. Enormous progress in understanding the strategies of nucleic acids catalysts has been made by providing thorough structural fundaments (e.g. first structure of a DNAzyme, structures of ribozyme transition state mimics) in combination with functional assays and atomic mutagenesis.
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Affiliation(s)
- Ronald Micura
- Institute of Organic Chemistry and Center for Molecular Biosciences Innsbruck CMBI, Leopold-Franzens University Innsbruck, Innsbruck, Austria.
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29
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Sett A, Zara L, Dausse E, Toulmé JJ. Engineering Light-Up Aptamers for the Detection of RNA Hairpins through Kissing Interaction. Anal Chem 2020; 92:9113-9117. [PMID: 32498509 DOI: 10.1021/acs.analchem.0c01378] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Aptasensors are biosensors that include aptamers for detecting a target of interest. We engineered signaling aptasensors for the detection of RNA hairpins from the previously described malachite green (MG) RNA aptamer. The top part of this imperfect hairpin aptamer was modified in such a way that it can engage loop-loop (so-called kissing) interactions with RNA hairpins displaying partly complementary apical loops. These newly derived oligonucleotides named malaswitches bind their cognate fluorogenic ligand (MG) exclusively when RNA-RNA kissing complexes are formed, whereas MG does not bind to malaswitches alone. Consequently, the formation of the ternary target RNA-malaswitch RNA-MG complex results in fluorescence emission, and malaswitches constitute sensors for detecting RNA hairpins. Malaswitches were designed that specifically detect precursors of microRNAs let7b and miR-206.
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Affiliation(s)
- Arghya Sett
- ARNA Laboratory, Inserm U1212, CNRS UMR5320, University of Bordeaux, 33076 Bordeaux, France
| | - Lorena Zara
- ARNA Laboratory, Inserm U1212, CNRS UMR5320, University of Bordeaux, 33076 Bordeaux, France.,Novaptech, 146 rue Léo Saignat, 33076 Bordeaux, France
| | - Eric Dausse
- ARNA Laboratory, Inserm U1212, CNRS UMR5320, University of Bordeaux, 33076 Bordeaux, France
| | - Jean-Jacques Toulmé
- ARNA Laboratory, Inserm U1212, CNRS UMR5320, University of Bordeaux, 33076 Bordeaux, France.,Novaptech, 146 rue Léo Saignat, 33076 Bordeaux, France
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30
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The Growing Interest in Development of Innovative Optical Aptasensors for the Detection of Antimicrobial Residues in Food Products. BIOSENSORS-BASEL 2020; 10:bios10030021. [PMID: 32138274 PMCID: PMC7146278 DOI: 10.3390/bios10030021] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/20/2020] [Accepted: 02/24/2020] [Indexed: 12/26/2022]
Abstract
The presence of antimicrobial residues in food-producing animals can lead to harmful effects on the consumer (e.g., allergies, antimicrobial resistance, toxicological effects) and cause issues in food transformation (i.e., cheese, yogurts production). Therefore, to control antimicrobial residues in food products of animal origin, screening methods are of utmost importance. Microbiological and immunological methods (e.g., ELISA, dipsticks) are conventional screening methods. Biosensors are an innovative solution for the development of more performant screening methods. Among the different kinds of biosensing elements (e.g., antibodies, aptamers, molecularly imprinted polymers (MIP), enzymes), aptamers for targeting antimicrobial residues are in continuous development since 2000. Therefore, this review has highlighted recent advances in the development of aptasensors, which present multiple advantages over immunosensors. Most of the aptasensors described in the literature for the detection of antimicrobial residues in animal-derived food products are either optical or electrochemical sensors. In this review, I have focused on optical aptasensors and showed how nanotechnologies (nanomaterials, micro/nanofluidics, and signal amplification techniques) largely contribute to the improvement of their performance (sensitivity, specificity, miniaturization, portability). Finally, I have explored different techniques to develop multiplex screening methods. Multiplex screening methods are necessary for the wide spectrum detection of antimicrobials authorized for animal treatment (i.e., having maximum residue limits).
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31
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Duchardt-Ferner E, Juen M, Bourgeois B, Madl T, Kreutz C, Ohlenschläger O, Wöhnert J. Structure of an RNA aptamer in complex with the fluorophore tetramethylrhodamine. Nucleic Acids Res 2020; 48:949-961. [PMID: 31754719 PMCID: PMC6954400 DOI: 10.1093/nar/gkz1113] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 11/08/2019] [Accepted: 11/11/2019] [Indexed: 12/23/2022] Open
Abstract
RNA aptamers-artificially created RNAs with high affinity and selectivity for their target ligand generated from random sequence pools-are versatile tools in the fields of biotechnology and medicine. On a more fundamental level, they also further our general understanding of RNA-ligand interactions e. g. in regard to the relationship between structural complexity and ligand affinity and specificity, RNA structure and RNA folding. Detailed structural knowledge on a wide range of aptamer-ligand complexes is required to further our understanding of RNA-ligand interactions. Here, we present the atomic resolution structure of an RNA-aptamer binding to the fluorescent xanthene dye tetramethylrhodamine. The high resolution structure, solved by NMR-spectroscopy in solution, reveals binding features both common and different from the binding mode of other aptamers with affinity for ligands carrying planar aromatic ring systems such as the malachite green aptamer which binds to the tetramethylrhodamine related dye malachite green or the flavin mononucleotide aptamer.
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Affiliation(s)
- Elke Duchardt-Ferner
- Institute for Molecular Biosciences, Goethe University, Frankfurt/M., Max-von-Laue-Str. 9, D-60438 Frankfurt, Germany and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt/M., Max-von-Laue-Str. 9, D-60438 Frankfurt, Germany
| | - Michael Juen
- Institute of Organic Chemistry, Centre for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Benjamin Bourgeois
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Institute of Molecular Biology & Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Austria
| | - Tobias Madl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Institute of Molecular Biology & Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Austria
- BioTechMed-Graz, Graz, Austria
| | - Christoph Kreutz
- Institute of Organic Chemistry, Centre for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Oliver Ohlenschläger
- Leibniz-Institute on Aging - Fritz-Lipmann-Institute, Beutenbergstrasse 11, D-07745 Jena, Germany
| | - Jens Wöhnert
- Institute for Molecular Biosciences, Goethe University, Frankfurt/M., Max-von-Laue-Str. 9, D-60438 Frankfurt, Germany and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt/M., Max-von-Laue-Str. 9, D-60438 Frankfurt, Germany
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32
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A dimerization-based fluorogenic dye-aptamer module for RNA imaging in live cells. Nat Chem Biol 2019; 16:69-76. [PMID: 31636432 PMCID: PMC6920041 DOI: 10.1038/s41589-019-0381-8] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Accepted: 08/22/2019] [Indexed: 01/19/2023]
Abstract
Live-cell imaging of RNA has remained a challenge because of the lack of naturally fluorescent RNAs. Recently developed RNA aptamers that can light-up small fluorogenic dyes could overcome this limitation, but they still suffer from poor brightness and photostability. Here, we propose a concept of cell-permeable fluorogenic dimer of sulforhodamine B dyes (Gemini-561) and corresponding dimerized aptamer (o-Coral) that can drastically enhance performance of the current RNA imaging method. The unprecedented brightness and photostability together with high affinity of this complex allowed, for the first time, direct fluorescence imaging in live mammalian cells of RNA polymerase-III transcription products as well as messenger RNAs labelled with a single copy of the aptamer, i.e. without tag multimerization. The developed fluorogenic module enables fast and sensitive detection of RNA inside live cells, while the proposed design concept opens the route to new generation of ultrabright RNA probes.
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Danilevich VN, Kozlov SA, Shevchuk TV, Oleinikov VA, Sizova SV, Khodarovich YM, Mulyukin AL. Ribonucleic acid (RNA) condensation by thermal cycling with metal cations: yield of nanoparticles and their applicability for transfection. J Biomol Struct Dyn 2019; 38:3959-3971. [PMID: 31543001 DOI: 10.1080/07391102.2019.1671228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To the present, different efficient but expensive, multistage, and time-consuming technologies have been developed to deliver ribonucleic acids (RNA) into eukaryotic cells. Here, we report a simple and feasible solution to design RNA nanocarriers based on nucleic acid condensation by bi- and trivalent metal ions during thermal cycling. Efficient RNA conversion to nanoparticles with small size (10-50 nm) suitable for transfection was achieved using cations Ni2+, Co2+ or Cu2+ alone or in combination with Ca2+ at the specially selected concentrations (2.0 mM-3.5 mM), low ionic strength, and narrow pH range (8.0-8.5). Other ions - Mn2+, Zn2+, Tb3+, or Gd3+ - caused RNA-cleaving effect that was abolished in the presence of Ni2+, Co2+, Zn2+, or Cu2+. Naked RNA-metal ion nanoparticles were extremely unstable in phosphate buffer and sensitive to serum ribonucleases (RNases), and this problem was solved by treatment with polyarginines-16 and 8. Polyarginine-stabilized nanoparticles, containing malachite green (MG) aptamer RNA and metal cations, crossed the cell membrane, dissociated in the cytoplasm, and preserved the functionality of transported RNA, as judged from efficient transfection of human embryonic kidney 293 cells. The technology, involving RNA condensation by metal cations, can be used as a cheap alternative to produce nanoscale carriers to deliver various RNAs into cells in vitro and in vivo.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Vasily N Danilevich
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Sergey A Kozlov
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Taras V Shevchuk
- Branch of the M. M. Shemyakin and Yu. A. Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Pushchino, Moscow, Russia
| | - Vladimir A Oleinikov
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Svetlana V Sizova
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Yuriy M Khodarovich
- Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Science, Moscow, Russia
| | - Andrey L Mulyukin
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow, Russia
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Mitra J, Ha T. Nanomechanics and co-transcriptional folding of Spinach and Mango. Nat Commun 2019; 10:4318. [PMID: 31541108 PMCID: PMC6754394 DOI: 10.1038/s41467-019-12299-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/03/2019] [Indexed: 11/24/2022] Open
Abstract
Recent advances in fluorogen-binding “light-up” RNA aptamers have enabled protein-free detection of RNA in cells. Detailed biophysical characterization of folding of G-Quadruplex (GQ)-based light-up aptamers such as Spinach, Mango and Corn is still lacking despite the potential implications on their folding and function. In this work we employ single-molecule fluorescence-force spectroscopy to examine mechanical responses of Spinach2, iMangoIII and MangoIV. Spinach2 unfolds in four discrete steps as force is increased to 7 pN and refolds in reciprocal steps upon force relaxation. In contrast, GQ-core unfolding in iMangoIII and MangoIV occurs in one discrete step at forces >10 pN and refolding occurred at lower forces showing hysteresis. Co-transcriptional folding using superhelicases shows reduced misfolding propensity and allowed a folding pathway different from refolding. Under physiologically relevant pico-Newton levels of force, these aptamers may unfold in vivo and subsequently misfold. Understanding of the dynamics of RNA aptamers will aid engineering of improved fluorogenic modules for cellular applications. Light-up aptamers are widely used for fluorescence visualization of non-coding RNA in vivo. Here the authors employ single-molecule fluorescence-force spectroscopy to characterize the mechanical responses of the G-Quadruplex based light-up aptamers Spinach2, iMangoIII and MangoIV, which is of interest for the development of improved fluorogenic modules for imaging applications.
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Affiliation(s)
- Jaba Mitra
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Taekjip Ha
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins University, Baltimore, MD, 21205, USA. .,Department of Biophysics, Johns Hopkins University, Baltimore, MD, 21218, USA. .,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21218, USA. .,Howard Hughes Medical Institute, Baltimore, MD, 21218, USA.
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35
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Saha R, Chen IA. Effect of UV Radiation on Fluorescent RNA Aptamers' Functional and Templating Ability. Chembiochem 2019; 20:2609-2617. [PMID: 31125512 PMCID: PMC6899979 DOI: 10.1002/cbic.201900261] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Indexed: 12/25/2022]
Abstract
Damage from ultraviolet (UV) radiation was likely to be an important selection pressure during the origin of life. RNA is believed to have been central to the origin of life and might form the basis for simple synthetic cells. Although photodamage of DNA has been extensively studied, photodamage is highly dependent on local molecular context, and damage to functional RNAs has been relatively under‐studied. We irradiated two fluorescent RNA aptamers and monitored the loss of activity, folding, and the kinetics of lesion accumulation. The loss of activity differed depending on the aptamer, with the Spinach2 aptamer retaining substantial activity after long exposure times. The binding pocket was particularly susceptible to damage, and melting of the duplex regions increased susceptibility; this is consistent with the view that duplex formation is protective. At the same time, susceptibility varied greatly depending on context, thus emphasizing the importance of studying many different RNAs to understand UV hardiness.
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Affiliation(s)
- Ranajay Saha
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Irene A Chen
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, CA, 93106, USA.,Program in Biomolecular Sciences and Engineering, University of California, Santa Barbara, CA, 93106, USA.,Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, CA, 90095, USA
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Tracking RNA with light: selection, structure, and design of fluorescence turn-on RNA aptamers. Q Rev Biophys 2019; 52:e8. [PMID: 31423956 DOI: 10.1017/s0033583519000064] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Fluorescence turn-on aptamers, in vitro evolved RNA molecules that bind conditional fluorophores and activate their fluorescence, have emerged as RNA counterparts of the fluorescent proteins. Turn-on aptamers have been selected to bind diverse fluorophores, and they achieve varying degrees of specificity and affinity. These RNA-fluorophore complexes, many of which exceed the brightness of green fluorescent protein and their variants, can be used as tags for visualizing RNA localization and transport in live cells. Structure determination of several fluorescent RNAs revealed that they have diverse, unrelated overall architectures. As most of these RNAs activate the fluorescence of their ligands by restraining their photoexcited states into a planar conformation, their fluorophore binding sites have in common a planar arrangement of several nucleobases, most commonly a G-quartet. Nonetheless, each turn-on aptamer has developed idiosyncratic structural solutions to achieve specificity and efficient fluorescence turn-on. The combined structural diversity of fluorophores and turn-on RNA aptamers has already produced combinations that cover the visual spectrum. Further molecular evolution and structure-guided engineering is likely to produce fluorescent tags custom-tailored to specific applications.
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Luo X, Chen Z, Li H, Li W, Cui L, Huang J. Exploiting the application of l-aptamer with excellent stability: an efficient sensing platform for malachite green in fish samples. Analyst 2019; 144:4204-4209. [PMID: 31187804 DOI: 10.1039/c9an00332k] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Effective monitoring of the content of malachite green (MG) in aquaculture is of great importance for food safety. Traditional methods for MG assay, such as chromatography and spectroscopy, have been criticized for expensive instrumentation and complicated pretreatments. An MG RNA aptamer (MGA) is a powerful tool for immediate and rapid detection of MG. However, RNA is easily degraded by nucleases and is unstable in the environment, making accurate and reliable detection of MG difficult. In order to address the problems, an innovative levo (l)-MGA with excellent stability is designed to perform the specific recognition function. Interestingly, the gel electrophoresis and fluorescence measurement results indicate that this unnaturally occurring l-aptamer is resistant to nuclease degradation and it can be kept intact in the standard buffer solution under room temperature for quite a long time. A label-free, simple, and efficient method has been developed for sensitive detection of MG in fish tissue, which holds promising potential in food analysis and environmental monitoring.
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Affiliation(s)
- Xiaowei Luo
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Biomaterials Research Center, School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China. and Department of Chemistry, University of Washington, Washington 98195, USA
| | - Zhifeng Chen
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Biomaterials Research Center, School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China.
| | - Hongfeng Li
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Biomaterials Research Center, School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China.
| | - Wenqin Li
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Biomaterials Research Center, School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China.
| | - Liang Cui
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310008, China.
| | - Jiahao Huang
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering, Guangdong Provincial Key Laboratory of Medical Image Processing, Biomaterials Research Center, School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China.
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Hewitt WM, Calabrese DR, Schneekloth JS. Evidence for ligandable sites in structured RNA throughout the Protein Data Bank. Bioorg Med Chem 2019; 27:2253-2260. [PMID: 30982658 PMCID: PMC8283815 DOI: 10.1016/j.bmc.2019.04.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 04/01/2019] [Accepted: 04/06/2019] [Indexed: 10/27/2022]
Abstract
RNA has attracted considerable attention as a target for small molecules. However, methods to identify, study, and characterize suitable RNA targets have lagged behind strategies for protein targets. One approach that has received considerable attention for protein targets has been to utilize computational analysis to investigate ligandable "pockets" on proteins that are amenable to small molecule binding. These studies have shown that selected physical properties of pockets are important parameters that govern the ability of a structure to bind to small molecules. This work describes a similar analysis to study pockets on all RNAs in the Protein Data Bank (PDB). Using parameters such as buriedness, hydrophobicity, volume, and other properties, the set of all RNAs is analyzed and compared to all proteins. Considerable overlap is observed between the properties of pockets on RNAs and proteins. Thus, many RNAs are capable of populating conformations with pockets that are likely suitable for small molecule binding. Further, principal moment of inertia (PMI) calculations reveal that liganded RNAs exist in diverse structural space, much of which overlaps with protein structural space. Taken together, these results suggest that complex folded RNAs adopt unique structures with pockets that may represent viable opportunities for small molecule targeting.
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Affiliation(s)
- William M Hewitt
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, United States
| | - David R Calabrese
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, United States
| | - John S Schneekloth
- Chemical Biology Laboratory, National Cancer Institute, Frederick, MD 21702, United States.
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39
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Shah M, Shah LA, Khan MS, Nasar MQ, Rasheed S. Synthesis, fabrication and characterization of polymer microgel/photochromic dye-based sandwiched sensors. IRANIAN POLYMER JOURNAL 2019. [DOI: 10.1007/s13726-019-00719-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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40
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Truong L, Ferré-D'Amaré AR. From fluorescent proteins to fluorogenic RNAs: Tools for imaging cellular macromolecules. Protein Sci 2019; 28:1374-1386. [PMID: 31017335 DOI: 10.1002/pro.3632] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 04/23/2019] [Indexed: 01/01/2023]
Abstract
The explosion in genome-wide sequencing has revealed that noncoding RNAs are ubiquitous and highly conserved in biology. New molecular tools are needed for their study in live cells. Fluorescent RNA-small molecule complexes have emerged as powerful counterparts to fluorescent proteins, which are well established, universal tools in the study of proteins in cell biology. No naturally fluorescent RNAs are known; all current fluorescent RNA tags are in vitro evolved or engineered molecules that bind a conditionally fluorescent small molecule and turn on its fluorescence by up to 5000-fold. Structural analyses of several such fluorescence turn-on aptamers show that these compact (30-100 nucleotides) RNAs have diverse molecular architectures that can restrain their photoexcited fluorophores in their maximally fluorescent states, typically by stacking between planar nucleotide arrangements, such as G-quadruplexes, base triples, or base pairs. The diversity of fluorogenic RNAs as well as fluorophores that are cell permeable and bind weakly to endogenous cellular macromolecules has already produced RNA-fluorophore complexes that span the visual spectrum and are useful for tagging and visualizing RNAs in cells. Because the ligand binding sites of fluorogenic RNAs are not constrained by the need to autocatalytically generate fluorophores as are fluorescent proteins, they may offer more flexibility in molecular engineering to generate photophysical properties that are tailored to experimental needs.
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Affiliation(s)
- Lynda Truong
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, Maryland, 20892-8012
| | - Adrian R Ferré-D'Amaré
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, Maryland, 20892-8012
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41
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Jasinski DL, Binzel DW, Guo P. One-Pot Production of RNA Nanoparticles via Automated Processing and Self-Assembly. ACS NANO 2019; 13:4603-4612. [PMID: 30888787 PMCID: PMC6542271 DOI: 10.1021/acsnano.9b00649] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
From the original sequencing of the human genome, it was found that about 98.5% of the genome did not code for proteins. Subsequent studies have now revealed that a much larger portion of the genome is related to short or long noncoding RNAs that regulate cellular activities. In addition to the milestones of chemical and protein drugs, it has been proposed that RNA drugs or drugs targeting RNA will become the third milestone in drug development ( Shu , Y. ; Adv. Drug Deliv. Rev. 2014 , 66 , 74 . ). Currently, the yield and cost for RNA nanoparticle or RNA drug production requires improvement in order to advance the RNA field in both research and clinical translation by reducing the multiple tedious manufacturing steps. For example, with 98.5% incorporation efficiency of chemical synthesis of a 100 nucleotide RNA strand, RNA oligos will result with 78% contamination of aborted byproducts. Thus, RNA nanotechnology is one of the remedies, because large RNA can be assembled from small RNA fragments via bottom-up self-assembly. Here we report the one-pot production of RNA nanoparticles via automated processing and self-assembly. The continuous production of RNA by rolling circle transcription (RCT) using a circular dsDNA template is coupled with self-cleaving ribozymes encoded in the concatemeric RNA transcripts. Production was monitored in real-time. Automatic production of RNA fragments enabled their assembly either in situ or via one-pot co-transcription to obtain RNA nanoparticles of desired motifs and functionalities from bottom-up assembly of multiple RNA fragments. In combination with the RNA nanoparticle construction process, a purification method using a large-scale electrophoresis column was also developed.
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Affiliation(s)
| | | | - Peixuan Guo
- Center for RNA Nanobiotechnology and Nanomedicine; College of Pharmacy, Division of Pharmaceutics and Pharmaceutical Chemistry; College of Medicine, Department of Physiology & Cell Biology; Dorothy M. Davis Heart and Lung Research Institute; and James Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, United States
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42
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Chopra A, Sagredo S, Grossi G, Andersen ES, Simmel FC. Out-of-Plane Aptamer Functionalization of RNA Three-Helix Tiles. NANOMATERIALS 2019; 9:nano9040507. [PMID: 30986942 PMCID: PMC6523889 DOI: 10.3390/nano9040507] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 03/23/2019] [Accepted: 03/27/2019] [Indexed: 12/15/2022]
Abstract
Co-transcriptionally folding RNA nanostructures have great potential as biomolecular scaffolds, which can be used to organize small molecules or proteins into spatially ordered assemblies. Here, we develop an RNA tile composed of three parallel RNA double helices, which can associate into small hexagonal assemblies via kissing loop interactions between its two outer helices. The inner RNA helix is modified with an RNA motif found in the internal ribosome entry site (IRES) of the hepatitis C virus (HCV), which provides a 90° bend. This modification is used to functionalize the RNA structures with aptamers pointing perpendicularly away from the tile plane. We demonstrate modifications with the fluorogenic malachite green and Spinach aptamers as well with the protein-binding PP7 and streptavidin aptamers. The modified structures retain the ability to associate into larger assemblies, representing a step towards RNA hybrid nanostructures extending in three dimensions.
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Affiliation(s)
- Aradhana Chopra
- Physik-Department E14, Technische Universität München, 85748 Garching, Germany.
| | - Sandra Sagredo
- Physik-Department E14, Technische Universität München, 85748 Garching, Germany.
| | - Guido Grossi
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark.
| | - Ebbe S Andersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, 8000 Aarhus C, Denmark.
| | - Friedrich C Simmel
- Physik-Department E14, Technische Universität München, 85748 Garching, Germany.
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43
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Autour A, Bouhedda F, Cubi R, Ryckelynck M. Optimization of fluorogenic RNA-based biosensors using droplet-based microfluidic ultrahigh-throughput screening. Methods 2019; 161:46-53. [PMID: 30902664 DOI: 10.1016/j.ymeth.2019.03.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Revised: 03/17/2019] [Accepted: 03/18/2019] [Indexed: 12/19/2022] Open
Abstract
Biosensors are biological molecules able to detect and report the presence of a target molecule by the emission of a signal. Nucleic acids are particularly appealing for the design of such molecule since their great structural plasticity makes them able to specifically interact with a wide range of ligands and their structure can rearrange upon recognition to trigger a reporting event. A biosensor is typically made of three main domains: a sensing domain that is connected to a reporting domain via a communication module in charge of transmitting the sensing event through the molecule. The communication module is therefore an instrumental element of the sensor. This module is usually empirically developed through a trial-and-error strategy with the testing of only a few combinations judged relevant by the experimenter. In this work, we introduce a novel method combining the use of droplet-based microfluidics and next generation sequencing. This method allows to functionally characterize up to a million of different sequences in a single set of experiments and, by doing so, to exhaustively test every possible sequence permutations of the communication module. Here, we demonstrate the efficiency of the approach by isolating a set of optimized RNA biosensors able to sense theophylline and to convert this recognition into fluorescence emission.
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Affiliation(s)
- Alexis Autour
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, F-67000 Strasbourg, France
| | - Farah Bouhedda
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, F-67000 Strasbourg, France
| | - Roger Cubi
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, F-67000 Strasbourg, France
| | - Michael Ryckelynck
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, F-67000 Strasbourg, France.
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O'Hara JM, Marashi D, Morton S, Jaeger L, Grabow WW. Optimization of the Split-Spinach Aptamer for Monitoring Nanoparticle Assembly Involving Multiple Contiguous RNAs. NANOMATERIALS 2019; 9:nano9030378. [PMID: 30845655 PMCID: PMC6474029 DOI: 10.3390/nano9030378] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/04/2019] [Accepted: 03/04/2019] [Indexed: 12/16/2022]
Abstract
The fact that structural RNA motifs can direct RNAs to fold and self-assemble into predictable pre-defined structures is an attractive quality and driving force for RNA’s use in nanotechnology. RNA’s recognized diversity concerning cellular and synthetically selected functionalities, however, help explain why it continues to draw attention for new nano-applications. Herein, we report the modification of a bifurcated reporter system based on the previously documented Spinach aptamer/DFHBI fluorophore pair that affords the ability to confirm the assembly of contiguous RNA strands within the context of the previously reported multi-stranded RNA nanoring. Exploration of the sequence space associated with the base pairs flanking the aptamer core demonstrate that fluorescent feedback can be optimized to minimize the fluorescence associated with partially-assembled RNA nanorings. Finally, we demonstrate that the aptamer-integrated nanoring is capable of assembling directly from transcribed DNA in one pot.
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Affiliation(s)
- Jack M O'Hara
- Department of Chemistry and Biochemistry, Seattle Pacific University, Seattle, WA 918119-1997, USA.
| | - Dylan Marashi
- Department of Chemistry and Biochemistry, Seattle Pacific University, Seattle, WA 918119-1997, USA.
| | - Sean Morton
- Department of Chemistry and Biochemistry, Seattle Pacific University, Seattle, WA 918119-1997, USA.
| | - Luc Jaeger
- Department of Chemistry and Biochemistry, Biomolecular Science and Engineering Program, University of California, Santa Barbara, CA 93106-9510, USA.
| | - Wade W Grabow
- Department of Chemistry and Biochemistry, Seattle Pacific University, Seattle, WA 918119-1997, USA.
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45
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Silverman AD, Kelley-Loughnane N, Lucks JB, Jewett MC. Deconstructing Cell-Free Extract Preparation for in Vitro Activation of Transcriptional Genetic Circuitry. ACS Synth Biol 2019; 8:403-414. [PMID: 30596483 PMCID: PMC6584022 DOI: 10.1021/acssynbio.8b00430] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recent advances in cell-free gene expression (CFE) systems have enabled their use for a host of synthetic biology applications, particularly for rapid prototyping of genetic circuits and biosensors. Despite the proliferation of cell-free protein synthesis platforms, the large number of currently existing protocols for making CFE extracts muddles the collective understanding of how the extract preparation method affects its functionality. A key aspect of extract performance relevant to many applications is the activity of the native host transcriptional machinery that can mediate protein synthesis. However, protein yields from genes transcribed in vitro by the native Escherichia coli RNA polymerase are variable for different extract preparation techniques, and specifically low in some conventional crude extracts originally optimized for expression by the bacteriophage transcriptional machinery. Here, we show that cell-free expression of genes under bacterial σ70 promoters is constrained by the rate of transcription in crude extracts, and that processing the extract with a ribosomal runoff reaction and subsequent dialysis alleviates this constraint. Surprisingly, these processing steps only enhance protein synthesis in genes under native regulation, indicating that the translation rate is unaffected. We further investigate the role of other common extract preparation process variants on extract performance and demonstrate that bacterial transcription is inhibited by including glucose in the growth culture but is unaffected by flash-freezing the cell pellet prior to lysis. Our final streamlined and detailed protocol for preparing extract by sonication generates extract that facilitates expression from a diverse set of sensing modalities including protein and RNA regulators. We anticipate that this work will clarify the methodology for generating CFE extracts that are active for biosensing using native transcriptional machinery and will encourage the further proliferation of cell-free gene expression technology for new applications.
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Affiliation(s)
- Adam D. Silverman
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Nancy Kelley-Loughnane
- 711th Human Performance Wing, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Julius B. Lucks
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, Illinois 60208, United States
- Member, Robert H. Lurie Comprehensive Cancer Center, and Member, Simpson Querrey Institute, Northwestern University, Chicago, Illinois 60611, United States
| | - Michael C. Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
- Interdisciplinary Biological Sciences Program, Northwestern University, Evanston, Illinois 60208, United States
- Member, Robert H. Lurie Comprehensive Cancer Center, and Member, Simpson Querrey Institute, Northwestern University, Chicago, Illinois 60611, United States
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Neubacher S, Hennig S. RNA Structure and Cellular Applications of Fluorescent Light-Up Aptamers. Angew Chem Int Ed Engl 2019; 58:1266-1279. [PMID: 30102012 PMCID: PMC6391945 DOI: 10.1002/anie.201806482] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Indexed: 12/16/2022]
Abstract
The cellular functions of RNA are not limited to their role as blueprints for protein synthesis. In particular, noncoding RNA, such as, snRNAs, lncRNAs, miRNAs, play important roles. With increasing numbers of RNAs being identified, it is well known that the transcriptome outnumbers the proteome by far. This emphasizes the great importance of functional RNA characterization and the need to further develop tools for these investigations, many of which are still in their infancy. Fluorescent light-up aptamers (FLAPs) are RNA sequences that can bind nontoxic, cell-permeable small-molecule fluorogens and enhance their fluorescence over many orders of magnitude upon binding. FLAPs can be encoded on the DNA level using standard molecular biology tools and are subsequently transcribed into RNA by the cellular machinery, so that they can be used as fluorescent RNA tags (FLAP-tags). In this Minireview, we give a brief overview of the fluorogens that have been developed and their binding RNA aptamers, with a special focus on published crystal structures. A summary of current and future cellular FLAP applications with an emphasis on the study of RNA-RNA and RNA-protein interactions using split-FLAP and Förster resonance energy transfer (FRET) systems is given.
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Affiliation(s)
- Saskia Neubacher
- Department of Chemistry & Pharmaceutical SciencesVU University AmsterdamDe Boelelaan 11081081HZAmsterdamThe Netherlands
| | - Sven Hennig
- Department of Chemistry & Pharmaceutical SciencesVU University AmsterdamDe Boelelaan 11081081HZAmsterdamThe Netherlands
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Fluorogenic RNA Aptamers: A Nano-platform for Fabrication of Simple and Combinatorial Logic Gates. NANOMATERIALS 2018; 8:nano8120984. [PMID: 30486495 PMCID: PMC6315349 DOI: 10.3390/nano8120984] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 11/16/2018] [Accepted: 11/20/2018] [Indexed: 12/14/2022]
Abstract
RNA aptamers that bind non-fluorescent dyes and activate their fluorescence are highly sensitive, nonperturbing, and convenient probes in the field of synthetic biology. These RNA molecules, referred to as light-up aptamers, operate as molecular nanoswitches that alter folding and fluorescence function in response to ligand binding, which is important in biosensing and molecular computing. Herein, we demonstrate a conceptually new generation of smart RNA nano-devices based on malachite green (MG)-binding RNA aptamer, which fluorescence output controlled by addition of short DNA oligonucleotides inputs. Four types of RNA switches possessing AND, OR, NAND, and NOR Boolean logic functions were created in modular form, allowing MG dye binding affinity to be changed by altering 3D conformation of the RNA aptamer. It is essential to develop higher-level logic circuits for the production of multi-task nanodevices for data processing, typically requiring combinatorial logic gates. Therefore, we further designed and synthetized higher-level half adder logic circuit by “in parallel” integration of two logic gates XOR and AND within a single RNA nanoparticle. The design utilizes fluorescence emissions from two different RNA aptamers: MG-binding RNA aptamer (AND gate) and Broccoli RNA aptamer that binds DFHBI dye (XOR gate). All computationally designed RNA devices were synthesized and experimentally tested in vitro. The ability to design smart nanodevices based on RNA binding aptamers offers a new route to engineer “label-free” ligand-sensing regulatory circuits, nucleic acid detection systems, and gene control elements.
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Neubacher S, Hennig S. RNA Structure and Cellular Applications of Fluorescent Light-Up Aptamers. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201806482] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Saskia Neubacher
- Department of Chemistry & Pharmaceutical Sciences; VU University Amsterdam; De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
| | - Sven Hennig
- Department of Chemistry & Pharmaceutical Sciences; VU University Amsterdam; De Boelelaan 1108 1081 HZ Amsterdam The Netherlands
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Shelke SA, Shao Y, Laski A, Koirala D, Weissman BP, Fuller JR, Tan X, Constantin TP, Waggoner AS, Bruchez MP, Armitage BA, Piccirilli JA. Structural basis for activation of fluorogenic dyes by an RNA aptamer lacking a G-quadruplex motif. Nat Commun 2018; 9:4542. [PMID: 30382099 PMCID: PMC6208384 DOI: 10.1038/s41467-018-06942-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 09/26/2018] [Indexed: 12/24/2022] Open
Abstract
The DIR2s RNA aptamer, a second-generation, in-vitro selected binder to dimethylindole red (DIR), activates the fluorescence of cyanine dyes, DIR and oxazole thiazole blue (OTB), allowing detection of two well-resolved emission colors. Using Fab BL3-6 and its cognate hairpin as a crystallization module, we solved the crystal structures of both the apo and OTB-SO3 bound forms of DIR2s at 2.0 Å and 1.8 Å resolution, respectively. DIR2s adopts a compact, tuning fork-like architecture comprised of a helix and two short stem-loops oriented in parallel to create the ligand binding site through tertiary interactions. The OTB-SO3 fluorophore binds in a planar conformation to a claw-like structure formed by a purine base-triple, which provides a stacking platform for OTB-SO3, and an unpaired nucleotide, which partially caps the binding site from the top. The absence of a G-quartet or base tetrad makes the DIR2s aptamer unique among fluorogenic RNAs with known 3D structure. The DIR2s RNA aptamer activates the fluorescence of cyanine dyes allowing detection of two well-resolved emission colors. Here authors solve the crystal structures of the apo and OTB-SO3 fluorophore-bound DIR2s and show how the fluorophore ligand is bound.
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Affiliation(s)
- Sandip A Shelke
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | - Yaming Shao
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | - Artur Laski
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | - Deepak Koirala
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | | | - James R Fuller
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA
| | - Xiaohong Tan
- Center for Nucleic Acids Science and Technology, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Tudor P Constantin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Alan S Waggoner
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Marcel P Bruchez
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Bruce A Armitage
- Center for Nucleic Acids Science and Technology, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.,Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA
| | - Joseph A Piccirilli
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL, 60637, USA. .,Department of Chemistry, The University of Chicago, Chicago, IL, 60637, USA.
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Saha S, Hetzke T, Prisner TF, Sigurdsson ST. Noncovalent spin-labeling of RNA: the aptamer approach. Chem Commun (Camb) 2018; 54:11749-11752. [PMID: 30276367 DOI: 10.1039/c8cc05597a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the first example of site-directed spin-labeling of unmodified RNA, a pyrrolidine-nitroxide derivative of tetramethylrosamine (TMR) was shown to bind with high affinity to the malachite green (MG) aptamer, as determined by continuous-wave (CW) electron paramagnetic resonance (EPR), pulsed electron-electron double resonance (PELDOR) and fluorescence spectroscopies.
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Affiliation(s)
- Subham Saha
- Department of Chemistry, Science Institute, Dunhaga 3, 107 Reykjavik, Iceland.
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