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Jiang G, Gao Y, Zhou N, Wang B. CRISPR-powered RNA sensing in vivo. Trends Biotechnol 2024:S0167-7799(24)00094-5. [PMID: 38734565 DOI: 10.1016/j.tibtech.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 04/02/2024] [Accepted: 04/02/2024] [Indexed: 05/13/2024]
Abstract
RNA sensing in vivo evaluates past or ongoing endogenous RNA disturbances, which is crucial for identifying cell types and states and diagnosing diseases. Recently, the CRISPR-driven genetic circuits have offered promising solutions to burgeoning challenges in RNA sensing. This review delves into the cutting-edge developments of CRISPR-powered RNA sensors in vivo, reclassifying these RNA sensors into four categories based on their working mechanisms, including programmable reassembly of split single-guide RNA (sgRNA), RNA-triggered RNA processing and protein cleavage, miRNA-triggered RNA interference (RNAi), and strand displacement reactions. Then, we discuss the advantages and challenges of existing methodologies in diverse application scenarios and anticipate and analyze obstacles and opportunities in forthcoming practical implementations.
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Affiliation(s)
- Guo Jiang
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, Zhejiang, China; ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311200, Zhejiang, China
| | - Yuanli Gao
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, Zhejiang, China; ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311200, Zhejiang, China; School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Nan Zhou
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, Zhejiang, China; ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311200, Zhejiang, China
| | - Baojun Wang
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, Zhejiang, China; ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 311200, Zhejiang, China.
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2
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Gao Y, Wang L, Wang B. Customizing cellular signal processing by synthetic multi-level regulatory circuits. Nat Commun 2023; 14:8415. [PMID: 38110405 PMCID: PMC10728147 DOI: 10.1038/s41467-023-44256-1] [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: 09/13/2023] [Accepted: 12/05/2023] [Indexed: 12/20/2023] Open
Abstract
As synthetic biology permeates society, the signal processing circuits in engineered living systems must be customized to meet practical demands. Towards this mission, novel regulatory mechanisms and genetic circuits with unprecedented complexity have been implemented over the past decade. These regulatory mechanisms, such as transcription and translation control, could be integrated into hybrid circuits termed "multi-level circuits". The multi-level circuit design will tremendously benefit the current genetic circuit design paradigm, from modifying basic circuit dynamics to facilitating real-world applications, unleashing our capabilities to customize cellular signal processing and address global challenges through synthetic biology.
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Affiliation(s)
- Yuanli Gao
- College of Chemical and Biological Engineering & ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou, 310058, China
- School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3FF, UK
| | - Lei Wang
- Center of Synthetic Biology and Integrated Bioengineering & School of Engineering, Westlake University, Hangzhou, 310030, China.
| | - Baojun Wang
- College of Chemical and Biological Engineering & ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou, 310058, China.
- Research Center for Biological Computation, Zhejiang Lab, Hangzhou, 311100, China.
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3
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Shi X, Won M, Tang C, Ding Q, Sharma A, Wang F, Kim JS. RNA splicing based on reporter genes system: Detection, imaging and applications. Coord Chem Rev 2023. [DOI: 10.1016/j.ccr.2022.214929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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Gambill L, Staubus A, Mo KW, Ameruoso A, Chappell J. A split ribozyme that links detection of a native RNA to orthogonal protein outputs. Nat Commun 2023; 14:543. [PMID: 36725852 PMCID: PMC9892565 DOI: 10.1038/s41467-023-36073-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 01/13/2023] [Indexed: 02/03/2023] Open
Abstract
Individual RNA remains a challenging signal to synthetically transduce into different types of cellular information. Here, we describe Ribozyme-ENabled Detection of RNA (RENDR), a plug-and-play strategy that uses cellular transcripts to template the assembly of split ribozymes, triggering splicing reactions that generate orthogonal protein outputs. To identify split ribozymes that require templating for splicing, we use laboratory evolution to evaluate the activities of different split variants of the Tetrahymena thermophila ribozyme. The best design delivers a 93-fold dynamic range of splicing with RENDR controlling fluorescent protein production in response to an RNA input. We further resolve a thermodynamic model to guide RENDR design, show how input signals can be transduced into diverse outputs, demonstrate portability across different bacteria, and use RENDR to detect antibiotic-resistant bacteria. This work shows how transcriptional signals can be monitored in situ and converted into different types of biochemical information using RNA synthetic biology.
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Affiliation(s)
- Lauren Gambill
- PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, 77005, USA
| | - August Staubus
- Department of Biosciences, Rice University, Houston, TX, 77005, USA
| | - Kim Wai Mo
- Department of Biosciences, Rice University, Houston, TX, 77005, USA
| | - Andrea Ameruoso
- Department of Biosciences, Rice University, Houston, TX, 77005, USA
| | - James Chappell
- PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, 77005, USA. .,Department of Biosciences, Rice University, Houston, TX, 77005, USA. .,Department of Bioengineering, Rice University, Houston, TX, 77005, USA.
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5
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Pelea O, Fulga TA, Sauka-Spengler T. RNA-Responsive gRNAs for Controlling CRISPR Activity: Current Advances, Future Directions, and Potential Applications. CRISPR J 2022; 5:642-659. [PMID: 36206027 PMCID: PMC9618385 DOI: 10.1089/crispr.2022.0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
CRISPR-Cas9 has emerged as a major genome manipulation tool. As Cas9 can cause off-target effects, several methods for controlling the expression of CRISPR systems were developed. Recent studies have shown that CRISPR activity could be controlled by sensing expression levels of endogenous transcripts. This is particularly interesting, as endogenous RNAs could harbor important information about the cell type, disease state, and environmental challenges cells are facing. Single-guide RNA (sgRNA) engineering played a major role in the development of RNA-responsive CRISPR systems. Following further optimizations, RNA-responsive sgRNAs could enable the development of novel therapeutic and research applications. This review introduces engineering strategies that could be employed to modify Streptococcus pyogenes sgRNAs with a focus on recent advances made toward the development of RNA-responsive sgRNAs. Future directions and potential applications of these technologies are also discussed.
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Affiliation(s)
- Oana Pelea
- Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; and Kansas City, Missouri, USA.,Address correspondence to: Oana Pelea, Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom,
| | - Tudor A. Fulga
- Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; and Kansas City, Missouri, USA
| | - Tatjana Sauka-Spengler
- Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; and Kansas City, Missouri, USA.,Stowers Institute for Medical Research, Kansas City, Missouri, USA.,Address correspondence to: Tatjana Sauka-Spengler, Radcliffe Department of Medicine, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom,
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6
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Miller CA, Ho JML, Bennett MR. Strategies for Improving Small-Molecule Biosensors in Bacteria. BIOSENSORS 2022; 12:bios12020064. [PMID: 35200325 PMCID: PMC8869690 DOI: 10.3390/bios12020064] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 05/03/2023]
Abstract
In recent years, small-molecule biosensors have become increasingly important in synthetic biology and biochemistry, with numerous new applications continuing to be developed throughout the field. For many biosensors, however, their utility is hindered by poor functionality. Here, we review the known types of mechanisms of biosensors within bacterial cells, and the types of approaches for optimizing different biosensor functional parameters. Discussed approaches for improving biosensor functionality include methods of directly engineering biosensor genes, considerations for choosing genetic reporters, approaches for tuning gene expression, and strategies for incorporating additional genetic modules.
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Affiliation(s)
- Corwin A. Miller
- Department of Biosciences, Rice University MS-140, 6100 Main St., Houston, TX 77005, USA; (C.A.M.); (J.M.L.H.)
| | - Joanne M. L. Ho
- Department of Biosciences, Rice University MS-140, 6100 Main St., Houston, TX 77005, USA; (C.A.M.); (J.M.L.H.)
| | - Matthew R. Bennett
- Department of Biosciences, Rice University MS-140, 6100 Main St., Houston, TX 77005, USA; (C.A.M.); (J.M.L.H.)
- Department of Bioengineering, Rice University MS-140, 6100 Main St., Houston, TX 77005, USA
- Correspondence:
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7
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Debiais M, Lelievre A, Smietana M, Müller S. Splitting aptamers and nucleic acid enzymes for the development of advanced biosensors. Nucleic Acids Res 2020; 48:3400-3422. [PMID: 32112111 PMCID: PMC7144939 DOI: 10.1093/nar/gkaa132] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/12/2020] [Accepted: 02/18/2020] [Indexed: 12/16/2022] Open
Abstract
In analogy to split-protein systems, which rely on the appropriate fragmentation of protein domains, split aptamers made of two or more short nucleic acid strands have emerged as novel tools in biosensor set-ups. The concept relies on dissecting an aptamer into a series of two or more independent fragments, able to assemble in the presence of a specific target. The stability of the assembled structure can further be enhanced by functionalities that upon folding would lead to covalent end-joining of the fragments. To date, only a few aptamers have been split successfully, and application of split aptamers in biosensing approaches remains as promising as it is challenging. Further improving the stability of split aptamer target complexes and with that the sensitivity as well as efficient working modes are important tasks. Here we review functional nucleic acid assemblies that are derived from aptamers and ribozymes/DNAzymes. We focus on the thrombin, the adenosine/ATP and the cocaine split aptamers as the three most studied DNA split systems and on split DNAzyme assemblies. Furthermore, we extend the subject into split light up RNA aptamers used as mimics of the green fluorescent protein (GFP), and split ribozymes.
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Affiliation(s)
- Mégane Debiais
- Institut des Biomolécules Max Mousseron, University of Montpellier, CNRS, ENCSM, Montpellier, France
| | - Amandine Lelievre
- University Greifswald, Institute for Biochemistry, Greifswald, Germany
| | - Michael Smietana
- Institut des Biomolécules Max Mousseron, University of Montpellier, CNRS, ENCSM, Montpellier, France
| | - Sabine Müller
- University Greifswald, Institute for Biochemistry, Greifswald, Germany
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Shi Y, Liu W, Zheng H, Li Z, Shi X, Cai S, Jiao Z, Mao W, Xie J, Tian J, Wang F. Imaging of pre-mRNA splicing in living subjects using a genetically encoded luciferase reporter. BIOMEDICAL OPTICS EXPRESS 2018; 9:518-528. [PMID: 29552390 PMCID: PMC5854055 DOI: 10.1364/boe.9.000518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/13/2017] [Accepted: 12/20/2017] [Indexed: 06/08/2023]
Abstract
Pre-mRNA splicing is an essential step in gene expression in most eukaryote genes. Here we present the feasibility of a genetically encoded luciferase reporter to monitor the pre-mRNA splicing process in living cells and animals. We showed that the splicing activity change induced by isoginkgetin could be readily visualized in vitro both in a dose and time dependent manner. Moreover, the pre-mRNA splicing process could be also obviously detected in mice by bioluminescence imaging and confirmed by RT-PCR. Our work provided a reporter system that allows high-throughput screening of chemical libraries to identify potential compounds leading to aberrant patterns of splicing.
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Affiliation(s)
- Yaru Shi
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
- Equal contribution
| | - Wei Liu
- Department of Hepatobiliary Surgery, Xijing Hospital, The Fourth Military Medical University, Xi’an, Shaanxi 710032, China
- Equal contribution
| | - Haifeng Zheng
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Zhiqiang Li
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Xiaorui Shi
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Shixuan Cai
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Zhiqiang Jiao
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Wenjie Mao
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Jinrong Xie
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
| | - Jie Tian
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
- CAS Key Laboratory of Molecular Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Fu Wang
- Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, School of Life Science and Technology, Xidian University, Xi’an, Shaanxi 710071, China
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9
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Göhring J, Fulcher N, Schilcher K, Barta A, Jacak J. Suitable transfection methods for single particle tracing in plant suspension cells. PLANT METHODS 2014; 10:15. [PMID: 24991230 PMCID: PMC4076440 DOI: 10.1186/1746-4811-10-15] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 05/15/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND A multitude of different imaging systems are already available to image genetically altered RNA species; however, only a few of these techniques are actually suitable to visualize endogenous RNA. One possibility is to use fluorescently-labelled and hybridization-sensitive probes. In order to yield more information about the exact localization and movement of a single RNA molecule, it is necessary to image such probes with highly sensitive microscope setups. More challenges arise if such experiments are conducted in plant cells due to their high autofluorescence and demanding transfection procedures. RESULTS Here, we report in planta imaging of single RNA molecules using fluorescently labeled molecular beacons. We tested three different transfection protocols in order to identify optimal conditions for transfection of fluorescent DNA probes and their subsequent detection at the single molecule level. CONCLUSIONS We found that an optimized heat shock protocol provided a vastly improved transfection method for small DNA molecules which were used for subsequent single RNA molecule detection in living plant suspension cells.
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Affiliation(s)
- Janett Göhring
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohrgasse 9/3, Vienna, Austria
| | - Nick Fulcher
- Gregor Mendel Institute, Dr. Bohrgasse 3, Vienna, Austria
| | - Kurt Schilcher
- Upper Austria University of Applied Sciences, Campus Linz, Linz, 4020, Austria
| | - Andrea Barta
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohrgasse 9/3, Vienna, Austria
| | - Jaroslaw Jacak
- Max F. Perutz Laboratories, Medical University of Vienna, Dr. Bohrgasse 9/3, Vienna, Austria
- Upper Austria University of Applied Sciences, Campus Linz, Linz, 4020, Austria
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10
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Franzini RM, Kool ET. Two successive reactions on a DNA template: a strategy for improving background fluorescence and specificity in nucleic acid detection. Chemistry 2011; 17:2168-75. [PMID: 21294182 DOI: 10.1002/chem.201002426] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Indexed: 12/24/2022]
Abstract
We report a new strategy for template-mediated fluorogenic chemistry that results in enhanced performance for the fluorescence detection of nucleic acids. In this approach, two successive templated reactions are required to induce a fluorescence signal, rather than only one. These novel fluorescein-labeled oligonucleotide probes, termed 2-STAR (STAR = Staudinger-triggered α-azidoether release) probes, contain two quencher groups tethered by separate reductively cleavable linkers. When a 2-STAR quenched probe successively binds adjacent to two mono-triphenylphosphine-(TPP)-DNAs or one dual-TPP-DNA, the two quenchers are released, resulting in a fluorescence signal. Because of the requirement for two consecutive reactions, 2-STAR probes display an unprecedented level of sequence specificity for template-mediated probe designs. At the same time, background emission generated by off-template reactions or incomplete quenching is among the lowest of any fluorogenic reactive probes for the detection of DNA or RNA.
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Affiliation(s)
- Raphael M Franzini
- Department of Chemistry, Stanford University, Stanford, CA-94305-5080, USA
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11
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Hasegawa S, Furukawa T, Saga T. Molecular MR imaging of cancer gene therapy: ferritin transgene reporter takes the stage. Magn Reson Med Sci 2010; 9:37-47. [PMID: 20585193 DOI: 10.2463/mrms.9.37] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Molecular imaging using magnetic resonance (MR) imaging has been actively investigated and made rapid progress in the past decade. Applied to cancer gene therapy, the technique's high spatial resolution allows evaluation of gene delivery into target tissues. Because noninvasive monitoring of the duration, location, and magnitude of transgene expression in tumor tissues or cells provides useful information for assessing therapeutic efficacy and optimizing protocols, molecular imaging is expected to become a critical step in the success of cancer gene therapy in the near future. We present a brief overview of the current status of molecular MR imaging, especially in vivo reporter gene imaging using ferritin and other reporters, discuss its application to cancer gene therapy, and present our research of MR imaging detection of electroporation-mediated cancer gene therapy using the ferritin reporter gene.
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Affiliation(s)
- Sumitaka Hasegawa
- Molecular Imaging Center, National Institute of Radiological Sciences, Inage-ku, Chiba, Japan.
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Masu H, Narita A, Tokunaga T, Ohashi M, Aoyama Y, Sando S. An Activatable siRNA Probe: Trigger-RNA-Dependent Activation of RNAi Function. Angew Chem Int Ed Engl 2009; 48:9481-3. [DOI: 10.1002/anie.200903925] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Masu H, Narita A, Tokunaga T, Ohashi M, Aoyama Y, Sando S. An Activatable siRNA Probe: Trigger-RNA-Dependent Activation of RNAi Function. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200903925] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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14
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Sando S, Narita A, Hayami M, Aoyama Y. Transcription monitoring using fused RNA with a dye-binding light-up aptamer as a tag: a blue fluorescent RNA. Chem Commun (Camb) 2008:3858-60. [PMID: 18726014 DOI: 10.1039/b808449a] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The "light-up" RNA aptamer-Hoechst pair can be used as a fluorescent tag to monitor transcription processes.
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Affiliation(s)
- Shinsuke Sando
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, Japan.
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Sando S, Narita A, Aoyama Y. Light-up Hoechst-DNA aptamer pair: generation of an aptamer-selective fluorophore from a conventional DNA-staining dye. Chembiochem 2008; 8:1795-803. [PMID: 17806095 DOI: 10.1002/cbic.200700325] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We have designed a strategy to generate a light-up fluorophore-aptamer pair based on a down-modification of a conventional DNA-staining dye to suppress its affinity to the original dsDNA targets, followed by reselection of aptamers that would bind to the modified dye. Following this line, we prepared a micropolarity-sensitive Hoechst derivative possessing two tBu groups with low affinity to the usual AT-rich dsDNA targets. DNA aptamers selected in vitro from a random pool worked as triggers to enhance the fluorescence of an otherwise nonfluorescent Hoechst derivative, and the shortened 25-mer sequence showed remarkable enhancement (light-up). The 25-mer sequence was split into binary aptamer probes, thus enabling us to detect a target nucleic acid sequence with a single-nucleotide resolution by use of unmodified DNA as a probe.
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Affiliation(s)
- Shinsuke Sando
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
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Abstract
Ribozymes are RNA molecules capable of associating with other RNA molecules through base-pairing and catalyzing various reactions involving phosphate group transfer. Of particular interest to us is the well known ribozyme from Tetrahymena thermophila capable of catalyzing RNA splicing in eukaryotic systems, chiefly because of its potential use as a gene therapy agent. In this article we review the progress made towards visualizing the RNA splicing mediated by the Tetrahymena ribozyme in single living mammalian cells with the beta-lactamase reporter system and highlight the development made in imaging RNA splicing with the luciferase reporter system in living animals.
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Affiliation(s)
- Gayatri Gowrishankar
- Molecular Imaging Program at Stanford, Department of Radiology & Bio-X Program, Cancer Biology Program, Stanford University School of Medicine, 1201 Welch Road, Stanford, California 94305-5484, USA.
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