1
|
Xu J, Hou J, Ding M, Wang Z, Chen T. Riboswitches, from cognition to transformation. Synth Syst Biotechnol 2023; 8:357-370. [PMID: 37325181 PMCID: PMC10265488 DOI: 10.1016/j.synbio.2023.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/20/2023] [Accepted: 05/25/2023] [Indexed: 06/17/2023] Open
Abstract
Riboswitches are functional RNA elements that regulate gene expression by directly detecting metabolites. Twenty years have passed since it was first discovered, researches on riboswitches are becoming increasingly standardized and refined, which could significantly promote people's cognition of RNA function as well. Here, we focus on some representative orphan riboswitches, enumerate the structural and functional transformation and artificial design of riboswitches including the coupling with ribozymes, hoping to attain a comprehensive understanding of riboswitch research.
Collapse
Affiliation(s)
- Jingdong Xu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China
- Frontier Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin, 300350, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, 300350, China
| | - Junyuan Hou
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China
- Frontier Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin, 300350, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, 300350, China
| | - Mengnan Ding
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China
- Frontier Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin, 300350, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, 300350, China
| | - Zhiwen Wang
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China
- Frontier Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin, 300350, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, 300350, China
| | - Tao Chen
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China
- Frontier Science Center for Synthetic Biology, Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin, 300350, China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, 300350, China
| |
Collapse
|
2
|
Tabuchi T, Yokobayashi Y. High-throughput screening of cell-free riboswitches by fluorescence-activated droplet sorting. Nucleic Acids Res 2022; 50:3535-3550. [PMID: 35253887 PMCID: PMC8989549 DOI: 10.1093/nar/gkac152] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/15/2022] [Accepted: 02/20/2022] [Indexed: 11/14/2022] Open
Abstract
Cell-free systems that display complex functions without using living cells are emerging as new platforms to test our understanding of biological systems as well as for practical applications such as biosensors and biomanufacturing. Those that use cell-free protein synthesis (CFPS) systems to enable genetically programmed protein synthesis have relied on genetic regulatory components found or engineered in living cells. However, biological constraints such as cell permeability, metabolic stability, and toxicity of signaling molecules prevent development of cell-free devices using living cells even if cell-free systems are not subject to such constraints. Efforts to engineer regulatory components directly in CFPS systems thus far have been based on low-throughput experimental approaches, limiting the availability of basic components to build cell-free systems with diverse functions. Here, we report a high-throughput screening method to engineer cell-free riboswitches that respond to small molecules. Droplet-sorting of riboswitch variants in a CFPS system rapidly identified cell-free riboswitches that respond to compounds that are not amenable to bacterial screening methods. Finally, we used a histamine riboswitch to demonstrate chemical communication between cell-sized droplets.
Collapse
Affiliation(s)
- Takeshi Tabuchi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
| | - Yohei Yokobayashi
- Nucleic Acid Chemistry and Engineering Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa 904-0495, Japan
| |
Collapse
|
3
|
Santos‐Moreno J, Schaerli Y. Using Synthetic Biology to Engineer Spatial Patterns. ACTA ACUST UNITED AC 2018; 3:e1800280. [DOI: 10.1002/adbi.201800280] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/14/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Javier Santos‐Moreno
- Department of Fundamental MicrobiologyUniversity of LausanneBiophore Building 1015 Lausanne Switzerland
| | - Yolanda Schaerli
- Department of Fundamental MicrobiologyUniversity of LausanneBiophore Building 1015 Lausanne Switzerland
| |
Collapse
|
4
|
Etzel M, Mörl M. Synthetic Riboswitches: From Plug and Pray toward Plug and Play. Biochemistry 2017; 56:1181-1198. [PMID: 28206750 DOI: 10.1021/acs.biochem.6b01218] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In synthetic biology, metabolic engineering, and gene therapy, there is a strong demand for orthogonal or externally controlled regulation of gene expression. Here, RNA-based regulatory devices represent a promising emerging alternative to proteins, allowing a fast and direct control of gene expression, as no synthesis of regulatory proteins is required. Besides programmable ribozyme elements controlling mRNA stability, regulatory RNA structures in untranslated regions are highly interesting for engineering approaches. Riboswitches are especially well suited, as they show a modular composition of sensor and response elements, allowing a free combination of different modules in a plug-and-play-like mode. The sensor or aptamer domain specifically interacts with a trigger molecule as a ligand, modulating the activity of the adjacent response domain that controls the expression of the genes located downstream, in most cases at the level of transcription or translation. In this review, we discuss the recent advances and strategies for designing such synthetic riboswitches based on natural or artificial components and readout systems, from trial-and-error approaches to rational design strategies. As the past several years have shown dramatic development in this fascinating field of research, we can give only a limited overview of the basic riboswitch design principles that is far from complete, and we apologize for not being able to consider every successful and interesting approach described in the literature.
Collapse
Affiliation(s)
- Maja Etzel
- Institute for Biochemistry, Leipzig University , Brüderstrasse 34, 04103 Leipzig, Germany
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University , Brüderstrasse 34, 04103 Leipzig, Germany
| |
Collapse
|
5
|
Mellin JR, Cossart P. Unexpected versatility in bacterial riboswitches. Trends Genet 2015; 31:150-6. [PMID: 25708284 DOI: 10.1016/j.tig.2015.01.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/23/2015] [Accepted: 01/23/2015] [Indexed: 12/11/2022]
Abstract
Bacterial riboswitches are elements present in the 5'-untranslated regions (UTRs) of mRNA molecules that bind to ligands and regulate the expression of downstream genes. Riboswitches typically regulate the expression of protein-coding genes. However, mechanisms of riboswitch-mediated regulation have recently been shown to be more diverse than originally thought, with reports showing that riboswitches can regulate the expression of noncoding RNAs and control the access of proteins, such as transcription termination factor Rho and RNase E, to a nascent RNA. Riboswitches are also increasingly used in biotechnology, with advances in the engineering of synthetic riboswitches and the development of riboswitch-based sensors. In this review we address the emerging roles and mechanisms of riboswitch-mediated regulation in natura and recent progress in the development of riboswitch-based technology.
Collapse
Affiliation(s)
- J R Mellin
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, 75015 Paris, France; Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 604, 75015 Paris, France; Institut National de la Recherche Agronomique (INRA) Unité USC2020, 75015 Paris, France
| | - Pascale Cossart
- Institut Pasteur, Unité des Interactions Bactéries-Cellules, 75015 Paris, France; Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 604, 75015 Paris, France; Institut National de la Recherche Agronomique (INRA) Unité USC2020, 75015 Paris, France.
| |
Collapse
|
6
|
Cao J, Arha M, Sudrik C, Schaffer DV, Kane RS. Bidirectional Regulation of mRNA Translation in Mammalian Cells by Using PUF Domains. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201402095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
7
|
Cao J, Arha M, Sudrik C, Schaffer DV, Kane RS. Bidirectional regulation of mRNA translation in mammalian cells by using PUF domains. Angew Chem Int Ed Engl 2014; 53:4900-4. [PMID: 24677733 DOI: 10.1002/anie.201402095] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Indexed: 12/12/2022]
Abstract
The regulation of gene expression is crucial in diverse areas of biological science, engineering, and medicine. A genetically encoded system based on the RNA binding domain of the Pumilio and FBF (PUF) proteins was developed for the bidirectional regulation (i.e., either upregulation or downregulation) of the translation of a target mRNA. PUF domains serve as designable scaffolds for the recognition of specific RNA elements and the specificity can be easily altered to target any 8-nucleotide RNA sequence. The expression of a reporter could be varied by over 17-fold when using PUF-based activators and repressors. The specificity of the method was established by using wild-type and mutant PUF domains. Furthermore, this method could be used to activate the translation of target mRNA downstream of PUF binding sites in a light-dependent manner. Such specific bidirectional control of mRNA translation could be particularly useful in the fields of synthetic biology, developmental biology, and metabolic engineering.
Collapse
Affiliation(s)
- Jicong Cao
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180 (USA)
| | | | | | | | | |
Collapse
|
8
|
Martini L, Mansy SS. Measuring riboswitch activity in vitro and in artificial cells with purified transcription-translation machinery. Methods Mol Biol 2014; 1111:153-164. [PMID: 24549618 DOI: 10.1007/978-1-62703-755-6_11] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We present a simple method to measure the real-time activity of riboswitches with purified components in vitro and inside of artificial cells. Typically, riboswitch activity is measured in vivo by exploiting β-galactosidase encoding constructs with a putative riboswitch sequence in the untranslated region. Additional in vitro characterization often makes use of in-line probing to explore conformational changes induced by ligand binding to the mRNA or analyses of transcript lengths in the presence and absence of ligand. However, riboswitches ultimately control protein levels and often times require accessory factors. Therefore, an in vitro system capable of monitoring protein production with fully defined components that can be supplemented with accessory factors would greatly aid riboswitch studies. Herein we present a system that is amenable to such analyses. Further, since the described system can be easily reconstituted within compartments to build artificial, cellular mimics with sensing capability, protocols are provided for building sense-response systems within water-in-oil emulsion compartments and lipid vesicles. Only standard laboratory equipment and commercially available material are exploited for the described assays, including DNA, purified transcription-translation machinery, i.e., the PURE system, and a spectrofluorometer.
Collapse
|
9
|
Vazquez-Anderson J, Contreras LM. Regulatory RNAs: charming gene management styles for synthetic biology applications. RNA Biol 2013; 10:1778-97. [PMID: 24356572 DOI: 10.4161/rna.27102] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
RNAs have many important functional properties, including that they are independently controllable and highly tunable. As a result of these advantageous properties, their use in a myriad of sophisticated devices has been widely explored. Yet, the exploitation of RNAs for synthetic applications is highly dependent on the ability to characterize the many new molecules that continue to be discovered by large-scale sequencing and high-throughput screening techniques. In this review, we present an exhaustive survey of the most recent synthetic bacterial riboswitches and small RNAs while emphasizing their virtues in gene expression management. We also explore the use of these RNA components as building blocks in the RNA synthetic biology toolbox and discuss examples of synthetic RNA components used to rewire bacterial regulatory circuitry. We anticipate that this field will expand its catalog of smart devices by mimicking and manipulating natural RNA mechanisms and functions.
Collapse
Affiliation(s)
- Jorge Vazquez-Anderson
- McKetta Department of Chemical Engineering; University of Texas at Austin; Austin, TX USA
| | - Lydia M Contreras
- McKetta Department of Chemical Engineering; University of Texas at Austin; Austin, TX USA
| |
Collapse
|
10
|
Huang W, Kim J, Jha S, Aboul-ela F. The impact of a ligand binding on strand migration in the SAM-I riboswitch. PLoS Comput Biol 2013; 9:e1003069. [PMID: 23704854 PMCID: PMC3656099 DOI: 10.1371/journal.pcbi.1003069] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Accepted: 04/09/2013] [Indexed: 11/29/2022] Open
Abstract
Riboswitches sense cellular concentrations of small molecules and use this information to adjust synthesis rates of related metabolites. Riboswitches include an aptamer domain to detect the ligand and an expression platform to control gene expression. Previous structural studies of riboswitches largely focused on aptamers, truncating the expression domain to suppress conformational switching. To link ligand/aptamer binding to conformational switching, we constructed models of an S-adenosyl methionine (SAM)-I riboswitch RNA segment incorporating elements of the expression platform, allowing formation of an antiterminator (AT) helix. Using Anton, a computer specially developed for long timescale Molecular Dynamics (MD), we simulated an extended (three microseconds) MD trajectory with SAM bound to a modeled riboswitch RNA segment. Remarkably, we observed a strand migration, converting three base pairs from an antiterminator (AT) helix, characteristic of the transcription ON state, to a P1 helix, characteristic of the OFF state. This conformational switching towards the OFF state is observed only in the presence of SAM. Among seven extended trajectories with three starting structures, the presence of SAM enhances the trend towards the OFF state for two out of three starting structures tested. Our simulation provides a visual demonstration of how a small molecule (<500 MW) binding to a limited surface can trigger a large scale conformational rearrangement in a 40 kDa RNA by perturbing the Free Energy Landscape. Such a mechanism can explain minimal requirements for SAM binding and transcription termination for SAM-I riboswitches previously reported experimentally.
Collapse
Affiliation(s)
- Wei Huang
- Department of Biological Science, Louisiana State University, Baton Rouge, Louisiana, United States of America
- Center for Computation & Technology, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Joohyun Kim
- Center for Computation & Technology, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Shantenu Jha
- Center for Computation & Technology, Louisiana State University, Baton Rouge, Louisiana, United States of America
- Department of Electrical and Computer Engineering, Rutgers University, Piscataway, New Jersey, United States of America
| | - Fareed Aboul-ela
- Department of Biological Science, Louisiana State University, Baton Rouge, Louisiana, United States of America
| |
Collapse
|
11
|
Qi H, Blanchard A, Lu T. Engineered genetic information processing circuits. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2013; 5:273-87. [DOI: 10.1002/wsbm.1216] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
12
|
Recent Advances in Ribonucleic Acid Interference (RNAi). NATIONAL ACADEMY SCIENCE LETTERS 2013. [DOI: 10.1007/s40009-012-0102-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
13
|
Loakes D. Nucleotides and nucleic acids; oligo- and polynucleotides. ORGANOPHOSPHORUS CHEMISTRY 2012. [DOI: 10.1039/9781849734875-00169] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- David Loakes
- Medical Research Council Laboratory of Molecular Biology, Hills Road Cambridge CB2 2QH UK
| |
Collapse
|
14
|
Chang AL, Wolf JJ, Smolke CD. Synthetic RNA switches as a tool for temporal and spatial control over gene expression. Curr Opin Biotechnol 2012; 23:679-88. [PMID: 22305712 DOI: 10.1016/j.copbio.2012.01.005] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 01/10/2012] [Accepted: 01/12/2012] [Indexed: 11/17/2022]
Abstract
The engineering of biological systems offers significant promise for advances in areas including health and medicine, chemical synthesis, energy production, and environmental sustainability. Realizing this potential requires tools that enable design of sophisticated genetic systems. The functional diversity of RNA makes it an attractive and versatile substrate for programming sensing, information processing, computation, and control functions. Recent advances in the design of synthetic RNA switches capable of detecting and responding to molecular and environmental signals enable dynamic modulation of gene expression through diverse mechanisms, including transcription, splicing, stability, RNA interference, and translation. Furthermore, implementation of these switches in genetic circuits highlights the potential for building synthetic cell systems targeted to applications in environmental remediation and next-generation therapeutics and diagnostics.
Collapse
Affiliation(s)
- Andrew L Chang
- Department of Chemistry, Stanford University, Stanford, CA 94305, United States
| | | | | |
Collapse
|
15
|
Gredell JA, Frei CS, Cirino PC. Protein and RNA engineering to customize microbial molecular reporting. Biotechnol J 2011; 7:477-99. [PMID: 22031507 DOI: 10.1002/biot.201100266] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/20/2011] [Accepted: 08/23/2011] [Indexed: 12/19/2022]
Abstract
Nature takes advantage of the malleability of protein and RNA sequence and structure to employ these macromolecules as molecular reporters whose conformation and functional roles depend on the presence of a specific ligand (an "effector" molecule). By following nature's example, ligand-responsive proteins and RNA molecules are now routinely engineered and incorporated into customized molecular reporting systems (biosensors). Microbial small-molecule biosensors and endogenous molecular reporters based on these sensing components find a variety of applications that include high-throughput screening of biosynthesis libraries, environmental monitoring, and novel gene regulation in synthetic biology. Here, we review recent advances in engineering small-molecule recognition by proteins and RNA and in coupling in vivo ligand binding to reporter-gene expression or to allosteric activation of a protein conferring a detectable phenotype. Emphasis is placed on microbial screening systems that serve as molecular reporters and facilitate engineering the ligand-binding component to recognize new molecules.
Collapse
Affiliation(s)
- Joseph A Gredell
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, TX, USA
| | | | | |
Collapse
|
16
|
Hodgman CE, Jewett MC. Cell-free synthetic biology: thinking outside the cell. Metab Eng 2011; 14:261-9. [PMID: 21946161 DOI: 10.1016/j.ymben.2011.09.002] [Citation(s) in RCA: 268] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 08/19/2011] [Accepted: 09/09/2011] [Indexed: 01/19/2023]
Abstract
Cell-free synthetic biology is emerging as a powerful approach aimed to understand, harness, and expand the capabilities of natural biological systems without using intact cells. Cell-free systems bypass cell walls and remove genetic regulation to enable direct access to the inner workings of the cell. The unprecedented level of control and freedom of design, relative to in vivo systems, has inspired the rapid development of engineering foundations for cell-free systems in recent years. These efforts have led to programmed circuits, spatially organized pathways, co-activated catalytic ensembles, rational optimization of synthetic multi-enzyme pathways, and linear scalability from the micro-liter to the 100-liter scale. It is now clear that cell-free systems offer a versatile test-bed for understanding why nature's designs work the way they do and also for enabling biosynthetic routes to novel chemicals, sustainable fuels, and new classes of tunable materials. While challenges remain, the emergence of cell-free systems is poised to open the way to novel products that until now have been impractical, if not impossible, to produce by other means.
Collapse
Affiliation(s)
- C Eric Hodgman
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, IL 60208, USA
| | | |
Collapse
|
17
|
Muranaka N, Yokobayashi Y. A synthetic riboswitch with chemical band-pass response. Chem Commun (Camb) 2010; 46:6825-7. [DOI: 10.1039/c0cc01438a] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|