1
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Dolcemascolo R, Ruiz R, Baldanta S, Goiriz L, Heras-Hernández M, Montagud-Martínez R, Rodrigo G. Probing the orthogonality and robustness of the mammalian RNA-binding protein Musashi-1 in Escherichia coli. J Biol Eng 2024; 18:52. [PMID: 39350178 PMCID: PMC11443895 DOI: 10.1186/s13036-024-00448-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 09/15/2024] [Indexed: 10/04/2024] Open
Abstract
RNA recognition motifs (RRMs) are widespread RNA-binding protein domains in eukaryotes, which represent promising synthetic biology tools due to their compact structure and efficient activity. Yet, their use in prokaryotes is limited and their functionality poorly characterized. Recently, we repurposed a mammalian Musashi protein containing two RRMs as a translation regulator in Escherichia coli. Here, employing high-throughput RNA sequencing, we explored the impact of Musashi expression on the transcriptomic and translatomic profiles of E. coli, revealing certain metabolic interference, induction of post-transcriptional regulatory processes, and spurious protein-RNA interactions. Engineered Musashi protein mutants displayed compromised regulatory activity, emphasizing the importance of both RRMs for specific and sensitive RNA binding. We found that a mutation known to impede allosteric regulation led to similar translation control activity. Evolutionary experiments disclosed a loss of function of the synthetic circuit in about 40 generations, with the gene coding for the Musashi protein showing a stability comparable to other heterologous genes. Overall, this work expands our understanding of RRMs for post-transcriptional regulation in prokaryotes and highlight their potential for biotechnological and biomedical applications.
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Affiliation(s)
- Roswitha Dolcemascolo
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain
| | - Raúl Ruiz
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain
| | - Sara Baldanta
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain
| | - Lucas Goiriz
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain
- Pure and Applied Mathematics University Research Institute (IUMPA), Polytechnic University of Valencia, Valencia, 46022, Spain
| | - María Heras-Hernández
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain
| | - Roser Montagud-Martínez
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain
| | - Guillermo Rodrigo
- Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, Paterna, 46980, Spain.
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2
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Koksaldi I, Park D, Atilla A, Kang H, Kim J, Seker UOS. RNA-Based Sensor Systems for Affordable Diagnostics in the Age of Pandemics. ACS Synth Biol 2024; 13:1026-1037. [PMID: 38588603 PMCID: PMC11036506 DOI: 10.1021/acssynbio.3c00698] [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: 11/21/2023] [Revised: 03/25/2024] [Accepted: 03/25/2024] [Indexed: 04/10/2024]
Abstract
In the era of the COVID-19 pandemic, the significance of point-of-care (POC) diagnostic tools has become increasingly vital, driven by the need for quick and precise virus identification. RNA-based sensors, particularly toehold sensors, have emerged as promising candidates for POC detection systems due to their selectivity and sensitivity. Toehold sensors operate by employing an RNA switch that changes the conformation when it binds to a target RNA molecule, resulting in a detectable signal. This review focuses on the development and deployment of RNA-based sensors for POC viral RNA detection with a particular emphasis on toehold sensors. The benefits and limits of toehold sensors are explored, and obstacles and future directions for improving their performance within POC detection systems are presented. The use of RNA-based sensors as a technology for rapid and sensitive detection of viral RNA holds great potential for effectively managing (dealing/coping) with present and future pandemics in resource-constrained settings.
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Affiliation(s)
- Ilkay
Cisil Koksaldi
- UNAM
− Institute of Materials Science and Nanotechnology, National
Nanotechnology Research Center (UNAM), Bilkent
University, Ankara 06800, Turkey
| | - Dongwon Park
- Department
of Life Sciences, Pohang University of Science
and Technology, Pohang 37673, South Korea
| | - Abdurahman Atilla
- UNAM
− Institute of Materials Science and Nanotechnology, National
Nanotechnology Research Center (UNAM), Bilkent
University, Ankara 06800, Turkey
| | - Hansol Kang
- Department
of Life Sciences, Pohang University of Science
and Technology, Pohang 37673, South Korea
| | - Jongmin Kim
- Department
of Life Sciences, Pohang University of Science
and Technology, Pohang 37673, South Korea
| | - Urartu Ozgur Safak Seker
- UNAM
− Institute of Materials Science and Nanotechnology, National
Nanotechnology Research Center (UNAM), Bilkent
University, Ankara 06800, Turkey
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3
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Buson F, Gao Y, Wang B. Genetic Parts and Enabling Tools for Biocircuit Design. ACS Synth Biol 2024; 13:697-713. [PMID: 38427821 DOI: 10.1021/acssynbio.3c00691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
Synthetic biology aims to engineer biological systems for customized tasks through the bottom-up assembly of fundamental building blocks, which requires high-quality libraries of reliable, modular, and standardized genetic parts. To establish sets of parts that work well together, synthetic biologists created standardized part libraries in which every component is analyzed in the same metrics and context. Here we present a state-of-the-art review of the currently available part libraries for designing biocircuits and their gene expression regulation paradigms at transcriptional, translational, and post-translational levels in Escherichia coli. We discuss the necessary facets to integrate these parts into complex devices and systems along with the current efforts to catalogue and standardize measurement data. To better display the range of available parts and to facilitate part selection in synthetic biology workflows, we established biopartsDB, a curated database of well-characterized and useful genetic part and device libraries with detailed quantitative data validated by the published literature.
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Affiliation(s)
- Felipe Buson
- 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, U.K
| | - 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, U.K
| | - Baojun Wang
- College of Chemical and Biological Engineering & ZJU-Hangzhou Global Scientific and Technological Innovation Center, Zhejiang University, Hangzhou 310058, China
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4
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Sumi S, Hamada M, Saito H. Deep generative design of RNA family sequences. Nat Methods 2024; 21:435-443. [PMID: 38238559 DOI: 10.1038/s41592-023-02148-8] [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: 05/01/2023] [Accepted: 12/07/2023] [Indexed: 03/13/2024]
Abstract
RNA engineering has immense potential to drive innovation in biotechnology and medicine. Despite its importance, a versatile platform for the automated design of functional RNA is still lacking. Here, we propose RNA family sequence generator (RfamGen), a deep generative model that designs RNA family sequences in a data-efficient manner by explicitly incorporating alignment and consensus secondary structure information. RfamGen can generate novel and functional RNA family sequences by sampling points from a semantically rich and continuous representation. We have experimentally demonstrated the versatility of RfamGen using diverse RNA families. Furthermore, we confirmed the high success rate of RfamGen in designing functional ribozymes through a quantitative massively parallel assay. Notably, RfamGen successfully generates artificial sequences with higher activity than natural sequences. Overall, RfamGen significantly improves our ability to design functional RNA and opens up new potential for generative RNA engineering in synthetic biology.
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Affiliation(s)
- Shunsuke Sumi
- Department of Life Science Frontiers, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
- Graduate School of Medicine, Kyoto University, Kyoto, Japan
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Michiaki Hamada
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan.
- Computational Bio Big-Data Open Innovation Laboratory (CBBD-OIL), National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan.
- Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
| | - Hirohide Saito
- Department of Life Science Frontiers, Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, Japan.
- Graduate School of Medicine, Kyoto University, Kyoto, Japan.
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5
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Dolcemascolo R, Heras-Hernández M, Goiriz L, Montagud-Martínez R, Requena-Menéndez A, Ruiz R, Pérez-Ràfols A, Higuera-Rodríguez RA, Pérez-Ropero G, Vranken WF, Martelli T, Kaiser W, Buijs J, Rodrigo G. Repurposing the mammalian RNA-binding protein Musashi-1 as an allosteric translation repressor in bacteria. eLife 2024; 12:RP91777. [PMID: 38363283 PMCID: PMC10942595 DOI: 10.7554/elife.91777] [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] [Indexed: 02/17/2024] Open
Abstract
The RNA recognition motif (RRM) is the most common RNA-binding protein domain identified in nature. However, RRM-containing proteins are only prevalent in eukaryotic phyla, in which they play central regulatory roles. Here, we engineered an orthogonal post-transcriptional control system of gene expression in the bacterium Escherichia coli with the mammalian RNA-binding protein Musashi-1, which is a stem cell marker with neurodevelopmental role that contains two canonical RRMs. In the circuit, Musashi-1 is regulated transcriptionally and works as an allosteric translation repressor thanks to a specific interaction with the N-terminal coding region of a messenger RNA and its structural plasticity to respond to fatty acids. We fully characterized the genetic system at the population and single-cell levels showing a significant fold change in reporter expression, and the underlying molecular mechanism by assessing the in vitro binding kinetics and in vivo functionality of a series of RNA mutants. The dynamic response of the system was well recapitulated by a bottom-up mathematical model. Moreover, we applied the post-transcriptional mechanism engineered with Musashi-1 to specifically regulate a gene within an operon, implement combinatorial regulation, and reduce protein expression noise. This work illustrates how RRM-based regulation can be adapted to simple organisms, thereby adding a new regulatory layer in prokaryotes for translation control.
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Affiliation(s)
- Roswitha Dolcemascolo
- Institute for Integrative Systems Biology (I2SysBio), CSIC – University of ValenciaPaternaSpain
- Department of Biotechnology, Polytechnic University of ValenciaValenciaSpain
| | - María Heras-Hernández
- Institute for Integrative Systems Biology (I2SysBio), CSIC – University of ValenciaPaternaSpain
| | - Lucas Goiriz
- Institute for Integrative Systems Biology (I2SysBio), CSIC – University of ValenciaPaternaSpain
- Department of Applied Mathematics, Polytechnic University of ValenciaValenciaSpain
| | - Roser Montagud-Martínez
- Institute for Integrative Systems Biology (I2SysBio), CSIC – University of ValenciaPaternaSpain
- Department of Biotechnology, Polytechnic University of ValenciaValenciaSpain
| | | | - Raúl Ruiz
- Institute for Integrative Systems Biology (I2SysBio), CSIC – University of ValenciaPaternaSpain
| | - Anna Pérez-Ràfols
- Giotto Biotech SRLSesto FiorentinoItaly
- Magnetic Resonance Center (CERM), Department of Chemistry Ugo Schiff, Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine (CIRMMP), University of FlorenceSesto FiorentinoItaly
| | - R Anahí Higuera-Rodríguez
- Dynamic Biosensors GmbHPlaneggGermany
- Department of Physics, Technical University of MunichGarchingGermany
| | - Guillermo Pérez-Ropero
- Ridgeview Instruments ABUppsalaSweden
- Department of Chemistry – BMC, Uppsala UniversityUppsalaSweden
| | - Wim F Vranken
- Structural Biology Brussels, Vrije Universiteit BrusselBrusselsBelgium
- Interuniversity Institute of Bioinformatics in Brussels, Université Libre de Bruxelles – Vrije Universiteit BrusselBrusselsBelgium
| | | | | | - Jos Buijs
- Ridgeview Instruments ABUppsalaSweden
- Department of Immunology, Genetics, and Pathology, Uppsala UniversityUppsalaSweden
| | - Guillermo Rodrigo
- Institute for Integrative Systems Biology (I2SysBio), CSIC – University of ValenciaPaternaSpain
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6
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Lauro C, Colarusso A, Calvanese M, Parrilli E, Tutino ML. Conditional gene silencing in the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125. Res Microbiol 2022; 173:103939. [DOI: 10.1016/j.resmic.2022.103939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 03/02/2022] [Accepted: 03/09/2022] [Indexed: 10/18/2022]
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7
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Yu Q, Ren K, You M. Genetically encoded RNA nanodevices for cellular imaging and regulation. NANOSCALE 2021; 13:7988-8003. [PMID: 33885099 PMCID: PMC8122502 DOI: 10.1039/d0nr08301a] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Nucleic acid-based nanodevices have been widely used in the fields of biosensing and nanomedicine. Traditionally, the majority of these nanodevices were first constructed in vitro using synthetic DNA or RNA oligonucleotides and then delivered into cells. Nowadays, the emergence of genetically encoded RNA nanodevices has provided a promising alternative approach for intracellular analysis and regulation. These genetically encoded RNA-based nanodevices can be directly transcribed and continuously produced inside living cells. A variety of highly precise and programmable nanodevices have been constructed in this way during the last decade. In this review, we will summarize the recent advances in the design and function of these artificial genetically encoded RNA nanodevices. In particular, we will focus on their applications in regulating cellular gene expression, imaging, logic operation, structural biology, and optogenetics. We believe these versatile RNA-based nanodevices will be broadly used in the near future to probe and program cells and other biological systems.
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Affiliation(s)
- Qikun Yu
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
| | - Kewei Ren
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
| | - Mingxu You
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA.
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8
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Kelly VW, Liang BK, Sirk SJ. Living Therapeutics: The Next Frontier of Precision Medicine. ACS Synth Biol 2020; 9:3184-3201. [PMID: 33205966 DOI: 10.1021/acssynbio.0c00444] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Modern medicine has long studied the mechanism and impact of pathogenic microbes on human hosts, but has only recently shifted attention toward the complex and vital roles that commensal and probiotic microbes play in both health and dysbiosis. Fueled by an enhanced appreciation of the human-microbe holobiont, the past decade has yielded countless insights and established many new avenues of investigation in this area. In this review, we discuss advances, limitations, and emerging frontiers for microbes as agents of health maintenance, disease prevention, and cure. We highlight the flexibility of microbial therapeutics across disease states, with special consideration for the rational engineering of microbes toward precision medicine outcomes. As the field advances, we anticipate that tools of synthetic biology will be increasingly employed to engineer functional living therapeutics with the potential to address longstanding limitations of traditional drugs.
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Affiliation(s)
- Vince W. Kelly
- Department of Bioengineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Benjamin K. Liang
- Department of Bioengineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Shannon J. Sirk
- Department of Bioengineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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9
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Hoyos M, Huber M, Förstner KU, Papenfort K. Gene autoregulation by 3' UTR-derived bacterial small RNAs. eLife 2020; 9:58836. [PMID: 32744240 PMCID: PMC7398697 DOI: 10.7554/elife.58836] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/23/2020] [Indexed: 01/01/2023] Open
Abstract
Negative feedback regulation, that is the ability of a gene to repress its own synthesis, is the most abundant regulatory motif known to biology. Frequently reported for transcriptional regulators, negative feedback control relies on binding of a transcription factor to its own promoter. Here, we report a novel mechanism for gene autoregulation in bacteria relying on small regulatory RNA (sRNA) and the major endoribonuclease, RNase E. TIER-seq analysis (transiently-inactivating-an-endoribonuclease-followed-by-RNA-seq) revealed ~25,000 RNase E-dependent cleavage sites in Vibrio cholerae, several of which resulted in the accumulation of stable sRNAs. Focusing on two examples, OppZ and CarZ, we discovered that these sRNAs are processed from the 3' untranslated region (3' UTR) of the oppABCDF and carAB operons, respectively, and base-pair with their own transcripts to inhibit translation. For OppZ, this process also triggers Rho-dependent transcription termination. Our data show that sRNAs from 3' UTRs serve as autoregulatory elements allowing negative feedback control at the post-transcriptional level.
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Affiliation(s)
- Mona Hoyos
- Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany.,Faculty of Biology I, Ludwig-Maximilians-University of Munich, Martinsried, Germany
| | - Michaela Huber
- Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany.,Faculty of Biology I, Ludwig-Maximilians-University of Munich, Martinsried, Germany
| | - Konrad U Förstner
- TH Köln - University of Applied Sciences, Institute of Information Science, Cologne, Germany.,ZB MED - Information Centre for Life Sciences, Cologne, Germany
| | - Kai Papenfort
- Friedrich Schiller University Jena, Institute of Microbiology, Jena, Germany.,Faculty of Biology I, Ludwig-Maximilians-University of Munich, Martinsried, Germany.,Microverse Cluster, Friedrich Schiller University Jena, Jena, Germany
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10
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Braun M, Fernau S, Dabrock P. (Re-)Designing Nature? An Overview and Outlook on the Ethical and Societal Challenges in Synthetic Biology. ACTA ACUST UNITED AC 2020; 3:e1800326. [PMID: 32648715 DOI: 10.1002/adbi.201800326] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 03/12/2019] [Indexed: 12/21/2022]
Abstract
This structured literature analysis aims to map the current, emerging, and predicted future of synthetic biology (SB) by putting the focus on the implied conceptual, societal, and ethical challenges. The central objective of the analysis is to provide an initial systematization of the ethical and socio-scientific debate on SB by structuring and categorizing widely discussed issues within the debate in recent years. Starting with the quest for possible definitions, issues of biosafety and biosecurity are emphasized. Furthermore, the focus is on the more conceptual challenges of SB, including the relationship between natural and synthetic, or concepts of life and living. From the very beginning, one specific characteristic of SB has been a strong entanglement with different forms of public participation. In some respects SB has already taken a leading position in claiming and orchestrating itself as an integrative and participatory discipline. After addressing SB as an emerging biotechnology at the interface between science and society, a venture is initiated to focus on the possible regulatory and governmental challenges which are entangled in SB.
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Affiliation(s)
- Matthias Braun
- Chair of Systematic Theology II (Ethics), Friedrich-Alexander-Universität Erlangen-Nürnberg, Kochstraße 6, 91054, Erlangen, Germany
| | - Sandra Fernau
- Chair of Systematic Theology II (Ethics), Friedrich-Alexander-Universität Erlangen-Nürnberg, Kochstraße 6, 91054, Erlangen, Germany
| | - Peter Dabrock
- Chair of Systematic Theology II (Ethics), Friedrich-Alexander-Universität Erlangen-Nürnberg, Kochstraße 6, 91054, Erlangen, Germany
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11
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Rahmat E, Kang Y. Yeast metabolic engineering for the production of pharmaceutically important secondary metabolites. Appl Microbiol Biotechnol 2020; 104:4659-4674. [DOI: 10.1007/s00253-020-10587-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 01/30/2020] [Accepted: 03/24/2020] [Indexed: 11/29/2022]
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12
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Montagud-Martínez R, Ventura J, Ballesteros-Garrido R, Rosado A, Rodrigo G. Probing the operability regime of an engineered ribocomputing unit in terms of dynamic range maintenance with extracellular changes and time. J Biol Eng 2020; 14:12. [PMID: 32226483 PMCID: PMC7098154 DOI: 10.1186/s13036-020-00234-5] [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: 11/07/2019] [Accepted: 03/10/2020] [Indexed: 11/16/2022] Open
Abstract
Synthetic biology aims at engineering gene regulatory circuits to end with cells (re)programmed on purpose to implement novel functions or discover natural behaviors. However, one overlooked question is whether the resulting circuits perform as intended in variety of environments or with time. Here, we considered a recently engineered genetic system that allows programming the cell to work as a minimal computer (arithmetic logic unit) in order to analyze its operability regime. This system involves transcriptional and post-transcriptional regulations. In particular, we studied the analog behavior of the system, the effect of physicochemical changes in the environment, the impact on cell growth rate of the heterologous expression, and the ability to maintain the arithmetic functioning over time. Conclusively, our results suggest 1) that there are wide input concentration ranges that the system can correctly process, the resulting outputs being predictable with a simple mathematical model, 2) that the engineered circuitry is quite sensitive to temperature effects, 3) that the expression of heterologous small RNAs is costly for the cell, not only of heterologous proteins, and 4) that a proper genetic reorganization of the system to reduce the amount of heterologous DNA in the cell can improve its evolutionary stability.
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Affiliation(s)
- Roser Montagud-Martínez
- 1Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, 46980 Paterna, Valencia Spain
| | - Jordi Ventura
- 1Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, 46980 Paterna, Valencia Spain
| | - Rafael Ballesteros-Garrido
- 1Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, 46980 Paterna, Valencia Spain.,2Present address: Department of Organic Chemistry, University of Valencia, 46100 Burjassot, Valencia Spain
| | - Arantxa Rosado
- 1Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, 46980 Paterna, Valencia Spain
| | - Guillermo Rodrigo
- 1Institute for Integrative Systems Biology (I2SysBio), CSIC - University of Valencia, 46980 Paterna, Valencia Spain
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13
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Haning K, Engels SM, Williams P, Arnold M, Contreras LM. Applying a New REFINE Approach in Zymomonas mobilis Identifies Novel sRNAs That Confer Improved Stress Tolerance Phenotypes. Front Microbiol 2020; 10:2987. [PMID: 31998271 PMCID: PMC6970203 DOI: 10.3389/fmicb.2019.02987] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/10/2019] [Indexed: 12/19/2022] Open
Abstract
As global controllers of gene expression, small RNAs represent powerful tools for engineering complex phenotypes. However, a general challenge prevents the more widespread use of sRNA engineering strategies: mechanistic analysis of these regulators in bacteria lags far behind their high-throughput search and discovery. This makes it difficult to understand how to efficiently identify useful sRNAs to engineer a phenotype of interest. To help address this, we developed a forward systems approach to identify naturally occurring sRNAs relevant to a desired phenotype: RNA-seq Examiner for Phenotype-Informed Network Engineering (REFINE). This pipeline uses existing RNA-seq datasets under different growth conditions. It filters the total transcriptome to locate and rank regulatory-RNA-containing regions that can influence a metabolic phenotype of interest, without the need for previous mechanistic characterization. Application of this approach led to the uncovering of six novel sRNAs related to ethanol tolerance in non-model ethanol-producing bacterium Zymomonas mobilis. Furthermore, upon overexpressing multiple sRNA candidates predicted by REFINE, we demonstrate improved ethanol tolerance reflected by up to an approximately twofold increase in relative growth rate compared to controls not expressing these sRNAs in 7% ethanol (v/v) RMG-supplemented media. In this way, the REFINE approach informs strain-engineering strategies that we expect are applicable for general strain engineering.
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Affiliation(s)
- Katie Haning
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, United States
| | - Sean M. Engels
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, United States
| | - Paige Williams
- Department of Aerospace Engineering & Engineering Mechanics, The University of Texas at Austin, Austin, TX, United States
| | - Margaret Arnold
- Department of Computer Science and Engineering, School of Engineering and Applied Sciences, University at Buffalo, Buffalo, NY, United States
| | - Lydia M. Contreras
- McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX, United States
- Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, United States
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14
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Reprogramming bacteria with RNA regulators. Biochem Soc Trans 2019; 47:1279-1289. [DOI: 10.1042/bst20190173] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/20/2022]
Abstract
Abstract
The revolution of genomics and growth of systems biology urged the creation of synthetic biology, an engineering discipline aiming at recreating and reprogramming cellular functions for industrial needs. There has been a huge effort in synthetic biology to develop versatile and programmable genetic regulators that would enable the precise control of gene expression. Synthetic RNA components have emerged as a solution, offering a diverse range of programmable functions, including signal sensing, gene regulation and the modulation of molecular interactions. Owing to their compactness, structure and way of action, several types of RNA devices that act on DNA, RNA and protein have been characterized and applied in synthetic biology. RNA-based approaches are more ‘economical' for the cell, since they are generally not translated. These RNA-based strategies act on a much shorter time scale than transcription-based ones and can be more efficient than protein-based mechanisms. In this review, we explore these RNA components as building blocks in the RNA synthetic biology field, first by explaining their natural mode of action and secondly discussing how these RNA components have been exploited to rewire bacterial regulatory circuitry.
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15
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Khambhati K, Bhattacharjee G, Gohil N, Braddick D, Kulkarni V, Singh V. Exploring the Potential of Cell-Free Protein Synthesis for Extending the Abilities of Biological Systems. Front Bioeng Biotechnol 2019; 7:248. [PMID: 31681738 PMCID: PMC6797904 DOI: 10.3389/fbioe.2019.00248] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 09/16/2019] [Indexed: 12/19/2022] Open
Abstract
Cell-free protein synthesis (CFPS) system is a simple, rapid, and sensitive tool that is devoid of membrane-bound barriers, yet contains all the mandatory substrates, biomolecules, and machineries required for the synthesis of the desired proteins. It has the potential to overcome loopholes in the current in vivo production systems and is a promising tool in both basic and applied scientific research. It facilitates a simplified organization of desired experiments with a variety of reaction conditions, making CFPS a powerful tool in biological research. It has been used for the expansion of genetic code, assembly of viruses, and in metabolic engineering for production of toxic and complex proteins. Subsequently, CFPS systems have emerged as potent technology for high-throughput production of membrane proteins, enzymes, and therapeutics. The present review highlights the recent advances and uses of CFPS systems in biomedical, therapeutic, and biotechnological applications. Additionally, we highlight possible solutions to the potential biosafety issues that may be encountered while using CFPS technology.
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Affiliation(s)
- Khushal Khambhati
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, India
| | - Gargi Bhattacharjee
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, India
| | - Nisarg Gohil
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, India
| | | | - Vishwesh Kulkarni
- School of Engineering, University of Warwick, Coventry, United Kingdom
| | - Vijai Singh
- Department of Biological Sciences and Biotechnology, Institute of Advanced Research, Gandhinagar, India
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16
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Vogel M, Weigand JE, Kluge B, Grez M, Suess B. A small, portable RNA device for the control of exon skipping in mammalian cells. Nucleic Acids Res 2019; 46:e48. [PMID: 29420816 PMCID: PMC5934650 DOI: 10.1093/nar/gky062] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 01/29/2018] [Indexed: 12/17/2022] Open
Abstract
Splicing is an essential and highly regulated process in mammalian cells. We developed a synthetic riboswitch that efficiently controls alternative splicing of a cassette exon in response to the small molecule ligand tetracycline. The riboswitch was designed to control the accessibility of the 3' splice site by placing the latter inside the closing stem of a conformationally controlled tetracycline aptamer. In the presence of tetracycline, the cassette exon is skipped, whereas it is included in the ligand's absence. The design allows for an easy, context-independent integration of the regulatory device into any gene of interest. Portability of the device was shown through its functionality in four different systems: a synthetic minigene, a reporter gene and two endogenous genes. Furthermore, riboswitch functionality to control cellular signaling cascades was demonstrated by using it to specifically induce cell death through the conditionally controlled expression of CD20, which is a target in cancer therapy.
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Affiliation(s)
- Marc Vogel
- Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany
| | - Julia E Weigand
- Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany
| | - Britta Kluge
- Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany
| | - Manuel Grez
- Institute for Tumor Biology and Experimental Therapy, Georg-Speyer-Haus, Paul-Ehrlich-Str. 42-44, 60596 Frankfurt/M, Germany
| | - Beatrix Suess
- Department of Biology, Technical University Darmstadt, Schnittspahnstr. 10, 64287 Darmstadt, Germany
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17
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Chu CC, Plangger R, Kreutz C, Al-Hashimi HM. Dynamic ensemble of HIV-1 RRE stem IIB reveals non-native conformations that disrupt the Rev-binding site. Nucleic Acids Res 2019; 47:7105-7117. [PMID: 31199872 PMCID: PMC6649712 DOI: 10.1093/nar/gkz498] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 05/21/2019] [Accepted: 06/07/2019] [Indexed: 01/01/2023] Open
Abstract
The HIV-1 Rev response element (RRE) RNA element mediates the nuclear export of intron containing viral RNAs by forming an oligomeric complex with the viral protein Rev. Stem IIB and nearby stem II three-way junction nucleate oligomerization through cooperative binding of two Rev molecules. Conformational flexibility at this RRE region has been shown to be important for Rev binding. However, the nature of the flexibility has remained elusive. Here, using NMR relaxation dispersion, including a new strategy for directly observing transient conformational states in large RNAs, we find that stem IIB alone or when part of the larger RREII three-way junction robustly exists in dynamic equilibrium with non-native excited state (ES) conformations that have a combined population of ∼20%. The ESs disrupt the Rev-binding site by changing local secondary structure, and their stabilization via point substitution mutations decreases the binding affinity to the Rev arginine-rich motif (ARM) by 15- to 80-fold. The ensemble clarifies the conformational flexibility observed in stem IIB, reveals long-range conformational coupling between stem IIB and the three-way junction that may play roles in cooperative Rev binding, and also identifies non-native RRE conformational states as new targets for the development of anti-HIV therapeutics.
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Affiliation(s)
- Chia-Chieh Chu
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Raphael Plangger
- Institute of Organic Chemistry and Center for Molecular Biosciences (CMBI), Universität Innsbruck, 6020 Innsbruck, Austria
| | - Christoph Kreutz
- Institute of Organic Chemistry and Center for Molecular Biosciences (CMBI), Universität Innsbruck, 6020 Innsbruck, Austria
| | - Hashim M Al-Hashimi
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Chemistry, Duke University, Durham, NC 27708, USA
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18
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Evolving methods for rational de novo design of functional RNA molecules. Methods 2019; 161:54-63. [PMID: 31059832 DOI: 10.1016/j.ymeth.2019.04.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/26/2019] [Accepted: 04/29/2019] [Indexed: 12/16/2022] Open
Abstract
Artificial RNA molecules with novel functionality have many applications in synthetic biology, pharmacy and white biotechnology. The de novo design of such devices using computational methods and prediction tools is a resource-efficient alternative to experimental screening and selection pipelines. In this review, we describe methods common to many such computational approaches, thoroughly dissect these methods and highlight open questions for the individual steps. Initially, it is essential to investigate the biological target system, the regulatory mechanism that will be exploited, as well as the desired components in order to define design objectives. Subsequent computational design is needed to combine the selected components and to obtain novel functionality. This process can usually be split into constrained sequence sampling, the formulation of an optimization problem and an in silico analysis to narrow down the number of candidates with respect to secondary goals. Finally, experimental analysis is important to check whether the defined design objectives are indeed met in the target environment and detailed characterization experiments should be performed to improve the mechanistic models and detect missing design requirements.
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19
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Advances in engineered trans-acting regulatory RNAs and their application in bacterial genome engineering. J Ind Microbiol Biotechnol 2019; 46:819-830. [PMID: 30887255 DOI: 10.1007/s10295-019-02160-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 03/05/2019] [Indexed: 12/15/2022]
Abstract
Small noncoding RNAs, a large class of ancient posttranscriptional regulators, are increasingly recognized and utilized as key modulators of gene expression in a broad range of microorganisms. Owing to their small molecular size and the central role of Watson-Crick base pairing in defining their interactions, structure and function, numerous diverse types of trans-acting RNA regulators that are functional at the DNA, mRNA and protein levels have been experimentally characterized. It has become increasingly clear that most small RNAs play critical regulatory roles in many processes and are, therefore, considered to be powerful tools for genetic engineering and synthetic biology. The trans-acting regulatory RNAs accelerate this ability to establish potential framework for genetic engineering and genome-scale engineering, which allows RNA structure characterization, easier to design and model compared to DNA or protein-based systems. In this review, we summarize recent advances in engineered trans-acting regulatory RNAs that are used in bacterial genome-scale engineering and in novel cellular capabilities as well as their implementation in wide range of biotechnological, biological and medical applications.
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20
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Norouzi M, Pickford AR, Butt LE, Vincent HA, Callaghan AJ. Application of mRNA Arrays for the Production of mCherry Reporter-Protein Arrays for Quantitative Gene Expression Analysis. ACS Synth Biol 2019; 8:207-215. [PMID: 30682244 DOI: 10.1021/acssynbio.8b00266] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The development of programmable regulators that precisely and predictably control gene expression is a major goal of synthetic biology. Consequently, rapid high-throughput biochemical methods capable of quantitatively analyzing all components of gene expression would be of value in the characterization and optimization of regulator performance. In this study we demonstrate a novel application of RNA arrays, involving the production of reporter-protein arrays, to gene expression analysis. This method enables simultaneous quantification of both the transcription and post-transcription/translation components of gene expression, and it also allows the assessment of the orthogonality of multiple regulators. We use our method to directly compare the performance of a series of previously characterized synthetic post-transcriptional riboregulators, thus demonstrating its utility in the development of synthetic regulatory modules and evaluation of gene expression regulation in general.
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Affiliation(s)
- Masoud Norouzi
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Andrew R. Pickford
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Louise E. Butt
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Helen A. Vincent
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
| | - Anastasia J. Callaghan
- School of Biological Sciences and Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth PO1 2DY, United Kingdom
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21
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Leistra AN, Curtis NC, Contreras LM. Regulatory non-coding sRNAs in bacterial metabolic pathway engineering. Metab Eng 2018; 52:190-214. [PMID: 30513348 DOI: 10.1016/j.ymben.2018.11.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 10/31/2018] [Accepted: 11/29/2018] [Indexed: 12/11/2022]
Abstract
Non-coding RNAs (ncRNAs) are versatile and powerful controllers of gene expression that have been increasingly linked to cellular metabolism and phenotype. In bacteria, identified and characterized ncRNAs range from trans-acting, multi-target small non-coding RNAs to dynamic, cis-encoded regulatory untranslated regions and riboswitches. These native regulators have inspired the design and construction of many synthetic RNA devices. In this work, we review the design, characterization, and impact of ncRNAs in engineering both native and exogenous metabolic pathways in bacteria. We also consider the opportunities afforded by recent high-throughput approaches for characterizing sRNA regulators and their corresponding networks to showcase their potential applications and impact in engineering bacterial metabolism.
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Affiliation(s)
- Abigail N Leistra
- McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E. Dean Keeton Street Stop C0400, Austin, TX 78712, USA
| | - Nicholas C Curtis
- McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E. Dean Keeton Street Stop C0400, Austin, TX 78712, USA
| | - Lydia M Contreras
- McKetta Department of Chemical Engineering, University of Texas at Austin, 200 E. Dean Keeton Street Stop C0400, Austin, TX 78712, USA.
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22
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Wang Y, Hoinka J, Liang Y, Adamus T, Swiderski P, Przytycka TM. AptaBlocks: Designing RNA complexes and accelerating RNA-based drug delivery systems. Nucleic Acids Res 2018; 46:8133-8142. [PMID: 29986050 PMCID: PMC6144873 DOI: 10.1093/nar/gky577] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 06/12/2018] [Accepted: 07/04/2018] [Indexed: 12/15/2022] Open
Abstract
RNA-based therapeutics, i.e. the utilization of synthetic RNA molecules to alter cellular functions, have the potential to address targets which are currently out of scope for traditional drug design pipelines. This potential however hinges on the ability to selectively deliver and internalize therapeutic RNAs into cells of interest. Cell internalizing RNA aptamers selected against surface receptors and discriminatively expressed on target cells hold particular promise as suitable candidates for such delivery agents. Specifically, these aptamers can be combined with a therapeutic cargo and facilitate internalization of the cargo into the cell of interest. A recently proposed method to obtain such aptamer-cargo constructs employs a double-stranded "sticky bridge" where the complementary strands constituting the bridge are conjugated with the aptamer and the cargo respectively. The design of appropriate sticky bridge sequences however has proven highly challenging given the structural and functional constraints imposed on them during synthesis and administration. These include, but are not limited to, guaranteed formation and stability of the complex, non-interference with the aptamer or the cargo, as well as the prevention of spurious aggregation of the molecules during incubation. In order to address these issues, we have developed AptaBlocks - a computational method to design RNA complexes that hybridize via sticky bridges. The effectiveness of our approach has been verified computationally, and experimentally in the context of drug delivery to pancreatic cancer cells. Importantly, AptaBlocks is a general method for the assembly of nucleic acid systems that, in addition to designing of RNA-based drug delivery systems, can be used in other applications of RNA nanotechnology. AptaBlocks is available at https://github.com/wyjhxq/AptaBlocks.
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Affiliation(s)
- Yijie Wang
- National Center of Biotechnology Information, National Library of Medicine, NIH, Bethesda MD 20894, USA
| | - Jan Hoinka
- National Center of Biotechnology Information, National Library of Medicine, NIH, Bethesda MD 20894, USA
| | - Yong Liang
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA
| | - Tomasz Adamus
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA
| | - Piotr Swiderski
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA
| | - Teresa M Przytycka
- National Center of Biotechnology Information, National Library of Medicine, NIH, Bethesda MD 20894, USA
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23
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Binary addition in a living cell based on riboregulation. PLoS Genet 2018; 14:e1007548. [PMID: 30024870 PMCID: PMC6067762 DOI: 10.1371/journal.pgen.1007548] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 07/31/2018] [Accepted: 07/09/2018] [Indexed: 11/19/2022] Open
Abstract
Synthetic biology aims at (re-)programming living cells like computers to perform new functions for a variety of applications. Initial work rested on transcription factors, but regulatory RNAs have recently gained much attention due to their high programmability. However, functional circuits mainly implemented with regulatory RNAs are quite limited. Here, we report the engineering of a fundamental arithmetic logic unit based on de novo riboregulation to sum two bits of information encoded in molecular concentrations. Our designer circuit robustly performs the intended computation in a living cell encoding the result as fluorescence amplitudes. The whole system exploits post-transcriptional control to switch on tightly silenced genes with small RNAs, together with allosteric transcription factors to sense the molecular signals. This important result demonstrates that regulatory RNAs can be key players in synthetic biology, and it paves the way for engineering more complex RNA-based biocomputers using this designer circuit as a building block.
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24
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Atitey K, Loskot P, Rees P. Determining the Transcription Rates Yielding Steady-State Production of mRNA in the Lac Genetic Switch of Escherichia coli. J Comput Biol 2018; 25:1023-1039. [PMID: 29957031 DOI: 10.1089/cmb.2018.0055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
To elucidate the regulatory dynamics of the gene expression activation and inactivation, an in silico biochemical model of the lac circuit in Escherichia coli was used to evaluate the transcription rates that yield the steady-state mRNA production in active and inactive states of the lac circuit. This result can be used in synthetic biology applications to understand the limits of the genetic synthesis. Since most genetic networks involve many interconnected components with positive and negative feedback control, intuitive understanding of their dynamics is often difficult to obtain. Although the kinetic model of the lac circuit considered involves only a single positive feedback, the developed computational framework can be used to evaluate supported ranges of other reaction rates in genetic circuits with more complex regulatory networks. More specifically, the inducible lac gene switch in E. coli is regulated by unbinding and binding of the inducer-repressor complexes to or from the DNA operator to switch the gene expression on and off. The dependency of mRNA production at steady state on different transcription rates and the repressor complexes has been studied by computer simulations in the Lattice Microbe software. Provided that the lac circuit is in active state, the transcription rate is independent of the inducer-repressor complexes present in the cell. In inactive state, the transcription rate is dependent on the specific inducer-repressor complex bound to the operator that inactivates the gene expression. We found that the repressor complex with the largest affinity to the operator yields the smallest range of the feasible transcription rates to yield the steady state while the lac circuit is in inactive state. In contrast, the steady state in active state can be obtained for any value of the transcription rate.
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Affiliation(s)
- Komlan Atitey
- College of Engineering, Swansea University , Swansea, United Kingdom
| | - Pavel Loskot
- College of Engineering, Swansea University , Swansea, United Kingdom
| | - Paul Rees
- College of Engineering, Swansea University , Swansea, United Kingdom
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25
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Zhang L, Wang M, Li N, Wang H, Qiu P, Pei L, Xu Z, Wang T, Gao E, Liu J, Liu S, Hu Q, Miao Y, Lindsey K, Tu L, Zhu L, Zhang X. Long noncoding RNAs involve in resistance to Verticillium dahliae, a fungal disease in cotton. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:1172-1185. [PMID: 29149461 PMCID: PMC5978870 DOI: 10.1111/pbi.12861] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 10/13/2017] [Accepted: 11/01/2017] [Indexed: 05/20/2023]
Abstract
Long noncoding RNAs (lncRNAs) have several known functions in plant development, but their possible roles in responding to plant disease remain largely unresolved. In this study, we described a comprehensive disease-responding lncRNA profiles in defence against a cotton fungal disease Verticillium dahliae. We further revealed the conserved and specific characters of disease-responding process between two cotton species. Conservatively for two cotton species, we found the expression dominance of induced lncRNAs in the Dt subgenome, indicating a biased induction pattern in the co-existing subgenomes of allotetraploid cotton. Comparative analysis of lncRNA expression and their proposed functions in resistant Gossypium barbadense cv. '7124' versus susceptible Gossypium hirsutum cv. 'YZ1' revealed their distinct disease response mechanisms. Species-specific (LS) lncRNAs containing more SNPs displayed a fiercer inducing level postinfection than the species-conserved (core) lncRNAs. Gene Ontology enrichment of LS lncRNAs and core lncRNAs indicates distinct roles in the process of biotic stimulus. Further functional analysis showed that two core lncRNAs, GhlncNAT-ANX2- and GhlncNAT-RLP7-silenced seedlings, displayed an enhanced resistance towards V. dahliae and Botrytis cinerea, possibly associated with the increased expression of LOX1 and LOX2. This study represents the first characterization of lncRNAs involved in resistance to fungal disease and provides new clues to elucidate cotton disease response mechanism.
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Affiliation(s)
- Lin Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Maojun Wang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Nannan Li
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Honglei Wang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Ping Qiu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Liuling Pei
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Zheng Xu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Tianyi Wang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Erlin Gao
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Junxia Liu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Shiming Liu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Qin Hu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Yuhuan Miao
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Keith Lindsey
- Integrative Cell Biology LaboratorySchool of Biological and Biomedical SciencesDurham UniversityDurhamUK
| | - Lili Tu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Longfu Zhu
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
| | - Xianlong Zhang
- National Key Laboratory of Crop Genetic ImprovementHuazhong Agricultural UniversityWuhanHubeiChina
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26
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Wang X, He Q, Yang Y, Wang J, Haning K, Hu Y, Wu B, He M, Zhang Y, Bao J, Contreras LM, Yang S. Advances and prospects in metabolic engineering of Zymomonas mobilis. Metab Eng 2018; 50:57-73. [PMID: 29627506 DOI: 10.1016/j.ymben.2018.04.001] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/31/2018] [Accepted: 04/01/2018] [Indexed: 12/22/2022]
Abstract
Biorefinery of biomass-based biofuels and biochemicals by microorganisms is a competitive alternative of traditional petroleum refineries. Zymomonas mobilis is a natural ethanologen with many desirable characteristics, which makes it an ideal industrial microbial biocatalyst for commercial production of desirable bioproducts through metabolic engineering. In this review, we summarize the metabolic engineering progress achieved in Z. mobilis to expand its substrate and product ranges as well as to enhance its robustness against stressful conditions such as inhibitory compounds within the lignocellulosic hydrolysates and slurries. We also discuss a few metabolic engineering strategies that can be applied in Z. mobilis to further develop it as a robust workhorse for economic lignocellulosic bioproducts. In addition, we briefly review the progress of metabolic engineering in Z. mobilis related to the classical synthetic biology cycle of "Design-Build-Test-Learn", as well as the progress and potential to develop Z. mobilis as a model chassis for biorefinery practices in the synthetic biology era.
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Affiliation(s)
- Xia Wang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Qiaoning He
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Yongfu Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Jingwen Wang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Katie Haning
- Institute for Cellular and Molecular Biology, Department of Chemical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX, United States.
| | - Yun Hu
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
| | - Bo Wu
- Key Laboratory of Development and Application of Rural Renewable Energy, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, South Renmin Road, Chengdu 610041, China.
| | - Mingxiong He
- Key Laboratory of Development and Application of Rural Renewable Energy, Biomass Energy Technology Research Centre, Biogas Institute of Ministry of Agriculture, South Renmin Road, Chengdu 610041, China.
| | - Yaoping Zhang
- DOE-Great Lakes Bioenergy Research Center (GLBRC), University of Wisconsin-Madison, Madison, WI, United States.
| | - Jie Bao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China.
| | - Lydia M Contreras
- Institute for Cellular and Molecular Biology, Department of Chemical Engineering, Cockrell School of Engineering, University of Texas at Austin, Austin, TX, United States.
| | - Shihui Yang
- Hubei Collaborative Innovation Center for Green Transformation of Bio-resources, Environmental Microbial Technology Center of Hubei Province, Hubei Key Laboratory of Industrial Biotechnology, College of Life Sciences, Hubei University, Wuhan 430062, China.
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27
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Lee YJ, Kim SJ, Moon TS. Multilevel Regulation of Bacterial Gene Expression with the Combined STAR and Antisense RNA System. ACS Synth Biol 2018; 7:853-865. [PMID: 29429328 DOI: 10.1021/acssynbio.7b00322] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Synthetic small RNA regulators have emerged as a versatile tool to predictably control bacterial gene expression. Owing to their simple design principles, small size, and highly orthogonal behavior, these engineered genetic parts have been incorporated into genetic circuits. However, efforts to achieve more sophisticated cellular functions using RNA regulators have been hindered by our limited ability to integrate different RNA regulators into complex circuits. Here, we present a combined RNA regulatory system in Escherichia coli that uses small transcription activating RNA (STAR) and antisense RNA (asRNA) to activate or deactivate target gene expression in a programmable manner. Specifically, we demonstrated that the activated target output by the STAR system can be deactivated by expressing two different types of asRNAs: one binds to and sequesters the STAR regulator, affecting the transcription process, while the other binds to the target mRNA, affecting the translation process. We improved deactivation efficiencies (up to 96%) by optimizing each type of asRNA and then integrating the two optimized asRNAs into a single circuit. Furthermore, we demonstrated that the combined STAR and asRNA system can control gene expression in a reversible way and can regulate expression of a gene in the genome. Lastly, we constructed and simultaneously tested two A AND NOT B logic gates in the same cell to show sophisticated multigene regulation by the combined system. Our approach establishes a methodology for integrating multiple RNA regulators to rationally control multiple genes.
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Affiliation(s)
- Young Je Lee
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Soo-Jung Kim
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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28
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Tian S, Das R. Primerize-2D: automated primer design for RNA multidimensional chemical mapping. Bioinformatics 2018; 33:1405-1406. [PMID: 28453672 DOI: 10.1093/bioinformatics/btw814] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 12/23/2016] [Indexed: 11/14/2022] Open
Abstract
Summary Rapid RNA synthesis of comprehensive single mutant libraries and targeted multiple mutant libraries is enabling new multidimensional chemical approaches to solve RNA structures. PCR assembly of DNA templates and in vitro transcription allow synthesis and purification of hundreds of RNA mutants in a cost-effective manner, with sharing of primers across constructs allowing significant reductions in expense. However, these protocols require organization of primer locations across numerous 96 well plates and guidance for pipetting, non-trivial tasks for which informatics and visualization tools can prevent costly errors. We report here an online tool to accelerate synthesis of large libraries of desired mutants through design and efficient organization of primers. The underlying program and graphical interface have been experimentally tested in our laboratory for RNA domains with lengths up to 300 nucleotides and libraries encompassing up to 960 variants. In addition to the freely available Primerize-2D server, the primer design code is available as a stand-alone Python package for broader applications. Availability and Implementation http://primerize2d.stanford.edu. Contact rhiju@stanford.edu. Supplementary information Supplementary data are available at Bioinformatics online.
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Affiliation(s)
| | - Rhiju Das
- Department of Biochemistry.,Department of Physics, Stanford University, Stanford, CA 94305, USA
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29
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Lee YJ, Moon TS. Design rules of synthetic non-coding RNAs in bacteria. Methods 2018; 143:58-69. [PMID: 29309838 DOI: 10.1016/j.ymeth.2018.01.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/31/2017] [Accepted: 01/03/2018] [Indexed: 12/21/2022] Open
Abstract
One of the long-term goals of synthetic biology is to develop designable genetic parts with predictable behaviors that can be utilized to implement diverse cellular functions. The discovery of non-coding RNAs and their importance in cellular processing have rapidly attracted researchers' attention towards designing functional non-coding RNA molecules. These synthetic non-coding RNAs have simple design principles governed by Watson-Crick base pairing, but exhibit increasingly complex functions. Importantly, due to their specific and modular behaviors, synthetic non-coding RNAs have been widely adopted to modulate transcription and translation of target genes. In this review, we summarize various design rules and strategies employed to engineer synthetic non-coding RNAs. Specifically, we discuss how RNA molecules can be transformed into powerful regulators and utilized to control target gene expression. With the establishment of generalizable non-coding RNA design rules, the research community will shift its focus to RNA regulators from protein regulators.
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Affiliation(s)
- Young Je Lee
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA.
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30
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Park SY, Yang D, Ha SH, Lee SY. Metabolic Engineering of Microorganisms for the Production of Natural Compounds. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/adbi.201700190] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Seon Young Park
- Metabolic and Biomolecular Engineering National Research Laboratory; Department of Chemical and Biomolecular Engineering (BK21 Plus Program); Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon 34141 Republic of Korea
| | - Dongsoo Yang
- Metabolic and Biomolecular Engineering National Research Laboratory; Department of Chemical and Biomolecular Engineering (BK21 Plus Program); Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon 34141 Republic of Korea
| | - Shin Hee Ha
- Metabolic and Biomolecular Engineering National Research Laboratory; Department of Chemical and Biomolecular Engineering (BK21 Plus Program); Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon 34141 Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory; Department of Chemical and Biomolecular Engineering (BK21 Plus Program); Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon 34141 Republic of Korea
- BioProcess Engineering Research Center; KAIST; Daejeon 34141 Republic of Korea
- BioInformatics Research Center; KAIST; Daejeon 34141 Republic of Korea
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31
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Chappell J, Westbrook A, Verosloff M, Lucks JB. Computational design of small transcription activating RNAs for versatile and dynamic gene regulation. Nat Commun 2017; 8:1051. [PMID: 29051490 PMCID: PMC5648800 DOI: 10.1038/s41467-017-01082-6] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/17/2017] [Indexed: 01/04/2023] Open
Abstract
A longstanding goal of synthetic biology has been the programmable control of cellular functions. Central to this is the creation of versatile regulatory toolsets that allow for programmable control of gene expression. Of the many regulatory molecules available, RNA regulators offer the intriguing possibility of de novo design-allowing for the bottom-up molecular-level design of genetic control systems. Here we present a computational design approach for the creation of a bacterial regulator called Small Transcription Activating RNAs (STARs) and create a library of high-performing and orthogonal STARs that achieve up to ~ 9000-fold gene activation. We demonstrate the versatility of these STARs-from acting synergistically with existing constitutive and inducible regulators, to reprogramming cellular phenotypes and controlling multigene metabolic pathway expression. Finally, we combine these new STARs with themselves and CRISPRi transcriptional repressors to deliver new types of RNA-based genetic circuitry that allow for sophisticated and temporal control of gene expression.
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Affiliation(s)
- James Chappell
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL, 60208, USA
| | - Alexandra Westbrook
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, 113 Ho Plaza, Ithaca, NY, 14583, USA
| | - Matthew Verosloff
- Interdisciplinary Biological Sciences Graduate Program, Northwestern University, 2204 Tech Drive, Evanston, IL, 60208, USA
| | - Julius B Lucks
- Department of Chemical and Biological Engineering, Northwestern University, 2145 Sheridan Rd, Evanston, IL, 60208, USA. .,Interdisciplinary Biological Sciences Graduate Program, Northwestern University, 2204 Tech Drive, Evanston, IL, 60208, USA.
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Marcus JI, Hassoun S, Nair NU. Computational prediction of functional abortive RNA in E. coli. Genomics 2017; 109:196-203. [PMID: 28347827 DOI: 10.1016/j.ygeno.2017.03.003] [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: 09/30/2016] [Revised: 02/24/2017] [Accepted: 03/22/2017] [Indexed: 11/26/2022]
Abstract
Failure by RNA polymerase to break contacts with promoter DNA results in release of bound RNA and re-initiation of transcription. These abortive RNAs were assumed to be non-functional but have recently been shown to affect termination in bacteriophage T7. Little is known about the functional role of these RNA in other genetic models. Using a computational approach, we investigated whether abortive RNA could exert function in E. coli. Fragments generated from 3780 transcription units were used as query sequences within their respective transcription units to search for possible binding sites. Sites that fell within known regulatory features were then ranked based upon the free energy of hybridization to the abortive. We further hypothesize about mechanisms of regulatory action for a select number of likely matches. Future experimental validation of these putative abortive-mRNA pairs may confirm our findings and promote exploration of functional abortive RNAs (faRNAs) in natural and synthetic systems.
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Affiliation(s)
- Jeremy I Marcus
- Department of Computer Science, Tufts University, Medford, MA 02155, United States
| | - Soha Hassoun
- Department of Computer Science, Tufts University, Medford, MA 02155, United States; Department of Chemical and Biological Engineering, Tufts University, Medford, MA 02155, United States
| | - Nikhil U Nair
- Department of Chemical and Biological Engineering, Tufts University, Medford, MA 02155, United States.
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33
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Exploring the potential of genome editing CRISPR-Cas9 technology. Gene 2017; 599:1-18. [DOI: 10.1016/j.gene.2016.11.008] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 10/18/2016] [Accepted: 11/06/2016] [Indexed: 12/26/2022]
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34
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Hoynes-O’Connor A, Moon TS. Development of Design Rules for Reliable Antisense RNA Behavior in E. coli. ACS Synth Biol 2016; 5:1441-1454. [PMID: 27434774 DOI: 10.1021/acssynbio.6b00036] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A key driver of synthetic biology is the development of designable genetic parts with predictable behaviors that can be quickly implemented in complex genetic systems. However, the intrinsic complexity of gene regulation can make the rational design of genetic parts challenging. This challenge is apparent in the design of antisense RNA (asRNA) regulators. Though asRNAs are well-known regulators, the literature governing their design is conflicting and leaves the synthetic biology community without clear asRNA design rules. The goal of this study is to perform a comprehensive experimental characterization and statistical analysis of 121 unique asRNA regulators in order to resolve the conflicts that currently exist in the literature. asRNAs usually consist of two regions, the Hfq binding site and the target binding region (TBR). First, the behaviors of several high-performing Hfq binding sites were compared, in terms of their ability to improve repression efficiencies and their orthogonality. Next, a large-scale analysis of TBR design parameters identified asRNA length, the thermodynamics of asRNA-mRNA complex formation, and the percent of target mismatch as key parameters for TBR design. These parameters were used to develop simple asRNA design rules. Finally, these design rules were applied to construct both a simple and a complex genetic circuit containing different asRNAs, and predictable behavior was observed in both circuits. The results presented in this study will drive synthetic biology forward by providing useful design guidelines for the construction of asRNA regulators with predictable behaviors.
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Affiliation(s)
- Allison Hoynes-O’Connor
- Department
of Energy, Environmental
and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Tae Seok Moon
- Department
of Energy, Environmental
and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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35
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Gebetsberger J, Micura R. Unwinding the twister ribozyme: from structure to mechanism. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 8. [PMID: 27863022 PMCID: PMC5408937 DOI: 10.1002/wrna.1402] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 09/12/2016] [Accepted: 10/10/2016] [Indexed: 11/12/2022]
Abstract
The twister ribozyme motif has been identified by bioinformatic means very recently. Currently, four crystal structures with ordered active sites together with a series of chemical and biochemical data provide insights into how this RNA accomplishes its efficient self‐cleavage. Of particular interest for a mechanistic proposal are structural distinctions observed in the active sites that concern the conformation of the U‐A cleavage site dinucleotide (in‐line alignment of the attacking 2′‐O nucleophile to the to‐be‐cleaved P—O5′ bond versus suboptimal alignments) as well as the presence/absence of Mg2+ ions at the scissile phosphate. All structures support the notion that an active site guanine and the conserved adenine at the cleavage site are important contributors to cleavage chemistry, likely being involved in general acid base catalysis. Evidence for innersphere coordination of a Mg2+ ion to the pro‐S nonbridging oxygen of the scissile phosphate stems from two of the four crystal structures. Together with the finding of thio/rescue effects for phosphorothioate substrates, this suggests the participation of divalent ions in the overall catalytic strategy employed by twister ribozymes. In this context, it is notable that twister retains wild‐type activity when the phylogenetically conserved stem P1 is deleted, able to cleave a single nucleotide only. WIREs RNA 2017, 8:e1402. doi: 10.1002/wrna.1402 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Jennifer Gebetsberger
- Institute of Organic Chemistry, Leopold-Franzens University and Center of Molecular Biosciences Innsbruck CMBI, Innsbruck, Austria
| | - Ronald Micura
- Institute of Organic Chemistry, Leopold-Franzens University and Center of Molecular Biosciences Innsbruck CMBI, Innsbruck, Austria
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36
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Regulatory RNAs in Bacillus subtilis: a Gram-Positive Perspective on Bacterial RNA-Mediated Regulation of Gene Expression. Microbiol Mol Biol Rev 2016; 80:1029-1057. [PMID: 27784798 DOI: 10.1128/mmbr.00026-16] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bacteria can employ widely diverse RNA molecules to regulate their gene expression. Such molecules include trans-acting small regulatory RNAs, antisense RNAs, and a variety of transcriptional attenuation mechanisms in the 5' untranslated region. Thus far, most regulatory RNA research has focused on Gram-negative bacteria, such as Escherichia coli and Salmonella. Hence, there is uncertainty about whether the resulting insights can be extrapolated directly to other bacteria, such as the Gram-positive soil bacterium Bacillus subtilis. A recent study identified 1,583 putative regulatory RNAs in B. subtilis, whose expression was assessed across 104 conditions. Here, we review the current understanding of RNA-based regulation in B. subtilis, and we categorize the newly identified putative regulatory RNAs on the basis of their conservation in other bacilli and the stability of their predicted secondary structures. Our present evaluation of the publicly available data indicates that RNA-mediated gene regulation in B. subtilis mostly involves elements at the 5' ends of mRNA molecules. These can include 5' secondary structure elements and metabolite-, tRNA-, or protein-binding sites. Importantly, sense-independent segments are identified as the most conserved and structured potential regulatory RNAs in B. subtilis. Altogether, the present survey provides many leads for the identification of new regulatory RNA functions in B. subtilis.
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37
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Horbal L, Luzhetskyy A. Dual control system - A novel scaffolding architecture of an inducible regulatory device for the precise regulation of gene expression. Metab Eng 2016; 37:11-23. [PMID: 27040671 PMCID: PMC4915818 DOI: 10.1016/j.ymben.2016.03.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 03/29/2016] [Accepted: 03/30/2016] [Indexed: 12/17/2022]
Abstract
Here, we present a novel scaffolding architecture of an inducible regulatory device. This dual control system is completely silent in the off stage and is coupled to the regulation of gene expression at both the transcriptional and translational levels. This system also functions as an AND gate. We demonstrated the effectiveness of the cumate-riboswitch dual control system for the control of pamamycin production in Streptomyces albus. Placing the cre recombinase gene under the control of this system permitted the construction of synthetic devices with non-volatile memory that sense the signal and respond by altering DNA at the chromosomal level, thereby producing changes that are heritable. In addition, we present a library of synthetic inducible promoters based on the previously described cumate switch. With only one inducer and different promoters, we demonstrate that simultaneous modulation of the expression of several genes to different levels in various operons is possible. Because all modules of the AND gates are functional in bacteria other than Streptomyces, we anticipate that these regulatory devices can be used to control gene expression in other Actinobacteria. The features described in this study make these systems promising tools for metabolic engineering and biotechnology in Actinobacteria.
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Affiliation(s)
- L Horbal
- Helmholtz Institute for Pharmaceutical Research, 66123 Saarbrücken, Germany; University of Saarland, Pharmaceutical Biotechnology, 66123 Saarbrucken, Germany
| | - A Luzhetskyy
- Helmholtz Institute for Pharmaceutical Research, 66123 Saarbrücken, Germany; University of Saarland, Pharmaceutical Biotechnology, 66123 Saarbrucken, Germany.
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38
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Mougiakos I, Bosma EF, de Vos WM, van Kranenburg R, van der Oost J. Next Generation Prokaryotic Engineering: The CRISPR-Cas Toolkit. Trends Biotechnol 2016; 34:575-587. [DOI: 10.1016/j.tibtech.2016.02.004] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 02/03/2016] [Accepted: 02/04/2016] [Indexed: 01/10/2023]
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39
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Rodrigo G, Majer E, Prakash S, Daròs JA, Jaramillo A, Poyatos JF. Exploring the Dynamics and Mutational Landscape of Riboregulation with a Minimal Synthetic Circuit in Living Cells. Biophys J 2016; 109:1070-6. [PMID: 26331264 DOI: 10.1016/j.bpj.2015.07.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 06/26/2015] [Accepted: 07/17/2015] [Indexed: 11/15/2022] Open
Abstract
The regulation of gene expression, triggered by conformational changes in RNA molecules, is widely observed in cellular systems. Here, we examine this mode of control by means of a model-based design and construction of a fully synthetic riboregulatory device. We present a theoretical framework that rests on a simple energy model to predict the dynamic response of such a system. Following an equilibrium description, our framework integrates thermodynamic properties—anticipated with an RNA physicochemical model—with a detailed description of the intermolecular interaction. The theoretical calculations are confirmed with an experimental characterization of the action of the riboregulatory device within living cells. This illustrates, more broadly, the predictability of genetic robustness on synthetic systems, and the faculty to engineer gene expression programs from a minimal set of first principles.
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Affiliation(s)
- Guillermo Rodrigo
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, Valencia, Spain; Institute of Systems and Synthetic Biology, Centre National de la Recherche Scientifique-Université d'Evry-Val d'Essonne, Évry, France.
| | - Eszter Majer
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, Valencia, Spain
| | - Satya Prakash
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - José-Antonio Daròs
- Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, Valencia, Spain
| | - Alfonso Jaramillo
- Institute of Systems and Synthetic Biology, Centre National de la Recherche Scientifique-Université d'Evry-Val d'Essonne, Évry, France; School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Juan F Poyatos
- Centro Nacional Biotecnología, Consejo Superior de Investigaciones Científicas, Madrid, Spain
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40
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Cuba Samaniego C, Giordano G, Kim J, Blanchini F, Franco E. Molecular Titration Promotes Oscillations and Bistability in Minimal Network Models with Monomeric Regulators. ACS Synth Biol 2016; 5:321-33. [PMID: 26797494 DOI: 10.1021/acssynbio.5b00176] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Molecular titration is emerging as an important biochemical interaction mechanism within synthetic devices built with nucleic acids and the CRISPR/Cas system. We show that molecular titration in the context of feedback circuits is a suitable mechanism to enhance the emergence of oscillations and bistable behaviors. We consider biomolecular modules that can be inhibited or activated by input monomeric regulators; the regulators compete with constitutive titrating species to determine the activity of their target. By tuning the titration rate and the concentration of titrating species, it is possible to modulate the delay and convergence speed of the transient response, and the steepness and dead zone of the stationary response of the modules. These phenomena favor the occurrence of oscillations when modules are interconnected to create a negative feedback loop; bistability is favored in a positive feedback interconnection. Numerical simulations are supported by mathematical analysis showing that the capacity of the closed loop systems to exhibit oscillations or bistability is structural.
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Affiliation(s)
- Christian Cuba Samaniego
- Mechanical Engineering, University of California at Riverside, Riverside, California 92521, United States
| | - Giulia Giordano
- Mathematics and Computer Science, University of Udine, 33100 Udine, Italy
| | - Jongmin Kim
- Wyss Institute for Biologically Inspired Engineering, Harvard University, 3 Blackfan Circle, Boston, Massachusetts 02115, United States
| | - Franco Blanchini
- Mathematics and Computer Science, University of Udine, 33100 Udine, Italy
| | - Elisa Franco
- Mechanical Engineering, University of California at Riverside, Riverside, California 92521, United States
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41
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Lee YJ, Hoynes-O'Connor A, Leong MC, Moon TS. Programmable control of bacterial gene expression with the combined CRISPR and antisense RNA system. Nucleic Acids Res 2016; 44:2462-73. [PMID: 26837577 PMCID: PMC4797300 DOI: 10.1093/nar/gkw056] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 01/20/2016] [Accepted: 01/20/2016] [Indexed: 12/16/2022] Open
Abstract
A central goal of synthetic biology is to implement diverse cellular functions by predictably controlling gene expression. Though research has focused more on protein regulators than RNA regulators, recent advances in our understanding of RNA folding and functions have motivated the use of RNA regulators. RNA regulators provide an advantage because they are easier to design and engineer than protein regulators, potentially have a lower burden on the cell and are highly orthogonal. Here, we combine the CRISPR system from Streptococcus pyogenes and synthetic antisense RNAs (asRNAs) in Escherichia coli strains to repress or derepress a target gene in a programmable manner. Specifically, we demonstrate for the first time that the gene target repressed by the CRISPR system can be derepressed by expressing an asRNA that sequesters a small guide RNA (sgRNA). Furthermore, we demonstrate that tunable levels of derepression can be achieved (up to 95%) by designing asRNAs that target different regions of a sgRNA and by altering the hybridization free energy of the sgRNA-asRNA complex. This new system, which we call the combined CRISPR and asRNA system, can be used to reversibly repress or derepress multiple target genes simultaneously, allowing for rational reprogramming of cellular functions.
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Affiliation(s)
- Young Je Lee
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Allison Hoynes-O'Connor
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Matthew C Leong
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
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42
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Luo S, Lu JY, Liu L, Yin Y, Chen C, Han X, Wu B, Xu R, Liu W, Yan P, Shao W, Lu Z, Li H, Na J, Tang F, Wang J, Zhang YE, Shen X. Divergent lncRNAs Regulate Gene Expression and Lineage Differentiation in Pluripotent Cells. Cell Stem Cell 2016; 18:637-52. [PMID: 26996597 DOI: 10.1016/j.stem.2016.01.024] [Citation(s) in RCA: 276] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 12/17/2015] [Accepted: 01/29/2016] [Indexed: 01/17/2023]
Abstract
Divergent lncRNAs that are transcribed in the opposite direction to nearby protein-coding genes comprise a significant proportion (∼20%) of total lncRNAs in mammalian genomes. Through genome-wide analysis, we found that the distribution of this lncRNA class strongly correlates with essential developmental regulatory genes. In pluripotent cells, divergent lncRNAs regulate the transcription of nearby genes. As an example, the divergent lncRNA Evx1as promotes transcription of its neighbor gene, EVX1, and regulates mesendodermal differentiation. At a single-cell level, early broad expression of Evx1as is followed by a rapid, high-level transcription of EVX1, supporting the idea that Evx1as plays an upstream role to facilitate EVX1 transcription. Mechanistically, Evx1as RNA binds to regulatory sites on chromatin, promotes an active chromatin state, and interacts with Mediator. Based on our analyses, we propose that the biological function of thousands of uncharacterized lncRNAs of this class may be inferred from the role of their neighboring adjacent genes.
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Affiliation(s)
- Sai Luo
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - J Yuyang Lu
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Lichao Liu
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Yafei Yin
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Chunyan Chen
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xue Han
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Bohou Wu
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Ronggang Xu
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Wei Liu
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Pixi Yan
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Wen Shao
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Zhi Lu
- School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Haitao Li
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Jie Na
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Fuchou Tang
- Biodynamic Optical Imaging Center, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China
| | - Jianlong Wang
- The Black Family Stem Cell Institute, Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yong E Zhang
- Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiaohua Shen
- Tsinghua-Peking Center for Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China.
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43
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McKeague M, Wong RS, Smolke CD. Opportunities in the design and application of RNA for gene expression control. Nucleic Acids Res 2016; 44:2987-99. [PMID: 26969733 PMCID: PMC4838379 DOI: 10.1093/nar/gkw151] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 02/29/2016] [Indexed: 12/15/2022] Open
Abstract
The past decade of synthetic biology research has witnessed numerous advances in the development of tools and frameworks for the design and characterization of biological systems. Researchers have focused on the use of RNA for gene expression control due to its versatility in sensing molecular ligands and the relative ease by which RNA can be modeled and designed compared to proteins. We review the recent progress in the field with respect to RNA-based genetic devices that are controlled through small molecule and protein interactions. We discuss new approaches for generating and characterizing these devices and their underlying components. We also highlight immediate challenges, future directions and recent applications of synthetic RNA devices in engineered biological systems.
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Affiliation(s)
- Maureen McKeague
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Remus S Wong
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Christina D Smolke
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
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Kong W, Kapuganti VS, Lu T. A gene network engineering platform for lactic acid bacteria. Nucleic Acids Res 2016; 44:e37. [PMID: 26503255 PMCID: PMC4770204 DOI: 10.1093/nar/gkv1093] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 10/08/2015] [Accepted: 10/09/2015] [Indexed: 11/28/2022] Open
Abstract
Recent developments in synthetic biology have positioned lactic acid bacteria (LAB) as a major class of cellular chassis for applications. To achieve the full potential of LAB, one fundamental prerequisite is the capacity for rapid engineering of complex gene networks, such as natural biosynthetic pathways and multicomponent synthetic circuits, into which cellular functions are encoded. Here, we present a synthetic biology platform for rapid construction and optimization of large-scale gene networks in LAB. The platform involves a copy-controlled shuttle for hosting target networks and two associated strategies that enable efficient genetic editing and phenotypic validation. By using a nisin biosynthesis pathway and its variants as examples, we demonstrated multiplex, continuous editing of small DNA parts, such as ribosome-binding sites, as well as efficient manipulation of large building blocks such as genes and operons. To showcase the platform, we applied it to expand the phenotypic diversity of the nisin pathway by quickly generating a library of 63 pathway variants. We further demonstrated its utility by altering the regulatory topology of the nisin pathway for constitutive bacteriocin biosynthesis. This work demonstrates the feasibility of rapid and advanced engineering of gene networks in LAB, fostering their applications in biomedicine and other areas.
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Affiliation(s)
- Wentao Kong
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Venkata S Kapuganti
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Ting Lu
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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Tools and Principles for Microbial Gene Circuit Engineering. J Mol Biol 2016; 428:862-88. [DOI: 10.1016/j.jmb.2015.10.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 10/05/2015] [Accepted: 10/06/2015] [Indexed: 12/26/2022]
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KARAGIANNIS P, FUJITA Y, SAITO H. RNA-based gene circuits for cell regulation. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2016; 92:412-422. [PMID: 27840389 PMCID: PMC5328788 DOI: 10.2183/pjab.92.412] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 08/24/2016] [Indexed: 05/20/2023]
Abstract
A major goal of synthetic biology is to control cell behavior. RNA-mediated genetic switches (RNA switches) are devices that serve this purpose, as they can control gene expressions in response to input signals. In general, RNA switches consist of two domains: an aptamer domain, which binds to an input molecule, and an actuator domain, which controls the gene expression. An input binding to the aptamer can cause the actuator to alter the RNA structure, thus changing access to translation machinery. The assembly of multiple RNA switches has led to complex gene circuits for cell therapies, including the selective killing of pathological cells and purification of cell populations. The inclusion of RNA binding proteins, such as L7Ae, increases the repertoire and precision of the circuit. In this short review, we discuss synthetic RNA switches for gene regulation and their potential therapeutic applications.
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Affiliation(s)
- Peter KARAGIANNIS
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Yoshihiko FUJITA
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Hirohide SAITO
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, Sakyo-ku, Kyoto, Japan
- Correspondence should be addressed: H. Saito, Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan (e-mail: )
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Programmable genetic circuits for pathway engineering. Curr Opin Biotechnol 2015; 36:115-21. [DOI: 10.1016/j.copbio.2015.08.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Revised: 08/04/2015] [Accepted: 08/09/2015] [Indexed: 02/06/2023]
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Regulatory RNA-assisted genome engineering in microorganisms. Curr Opin Biotechnol 2015; 36:85-90. [DOI: 10.1016/j.copbio.2015.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 07/18/2015] [Accepted: 08/09/2015] [Indexed: 01/05/2023]
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Synthetic scaffolds for pathway enhancement. Curr Opin Biotechnol 2015; 36:98-106. [DOI: 10.1016/j.copbio.2015.08.009] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 07/31/2015] [Accepted: 08/09/2015] [Indexed: 12/11/2022]
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Qi H, Li BZ, Zhang WQ, Liu D, Yuan YJ. Modularization of genetic elements promotes synthetic metabolic engineering. Biotechnol Adv 2015; 33:1412-9. [DOI: 10.1016/j.biotechadv.2015.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 01/12/2015] [Accepted: 04/05/2015] [Indexed: 01/24/2023]
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