1
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Shui S, Scheller L, Correia BE. Protein-based bandpass filters for controlling cellular signaling with chemical inputs. Nat Chem Biol 2024; 20:586-593. [PMID: 37957273 PMCID: PMC11062894 DOI: 10.1038/s41589-023-01463-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 09/29/2023] [Indexed: 11/15/2023]
Abstract
Biological signal processing is vital for cellular function. Similar to electronic circuits, cells process signals via integrated mechanisms. In electronics, bandpass filters transmit frequencies with defined ranges, but protein-based counterparts for controlled responses are lacking in engineered biological systems. Here, we rationally design protein-based, chemically responsive bandpass filters (CBPs) showing OFF-ON-OFF patterns that respond to chemical concentrations within a specific range and reject concentrations outside that range. Employing structure-based strategies, we designed a heterodimeric construct that dimerizes in response to low concentrations of a small molecule (ON), and dissociates at high concentrations of the same molecule (OFF). The CBPs have a multidomain architecture in which we used known drug receptors, a computationally designed protein binder and small-molecule inhibitors. This modular system allows fine-tuning for optimal performance in terms of bandwidth, response, cutoff and fold changes. The CBPs were used to regulate cell surface receptor signaling pathways to control cellular activities in engineered cells.
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Affiliation(s)
- Sailan Shui
- Laboratory of Protein Design and Immunoengineering (LPDI)-STI-EPFL, Lausanne, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Leo Scheller
- Laboratory of Protein Design and Immunoengineering (LPDI)-STI-EPFL, Lausanne, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Bruno E Correia
- Laboratory of Protein Design and Immunoengineering (LPDI)-STI-EPFL, Lausanne, Switzerland.
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland.
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2
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Mousavi R, Lobo D. Automatic design of gene regulatory mechanisms for spatial pattern formation. NPJ Syst Biol Appl 2024; 10:35. [PMID: 38565850 PMCID: PMC10987498 DOI: 10.1038/s41540-024-00361-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 03/19/2024] [Indexed: 04/04/2024] Open
Abstract
Gene regulatory mechanisms (GRMs) control the formation of spatial and temporal expression patterns that can serve as regulatory signals for the development of complex shapes. Synthetic developmental biology aims to engineer such genetic circuits for understanding and producing desired multicellular spatial patterns. However, designing synthetic GRMs for complex, multi-dimensional spatial patterns is a current challenge due to the nonlinear interactions and feedback loops in genetic circuits. Here we present a methodology to automatically design GRMs that can produce any given two-dimensional spatial pattern. The proposed approach uses two orthogonal morphogen gradients acting as positional information signals in a multicellular tissue area or culture, which constitutes a continuous field of engineered cells implementing the same designed GRM. To efficiently design both the circuit network and the interaction mechanisms-including the number of genes necessary for the formation of the target spatial pattern-we developed an automated algorithm based on high-performance evolutionary computation. The tolerance of the algorithm can be configured to design GRMs that are either simple to produce approximate patterns or complex to produce precise patterns. We demonstrate the approach by automatically designing GRMs that can produce a diverse set of synthetic spatial expression patterns by interpreting just two orthogonal morphogen gradients. The proposed framework offers a versatile approach to systematically design and discover complex genetic circuits producing spatial patterns.
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Affiliation(s)
- Reza Mousavi
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD, USA
| | - Daniel Lobo
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD, USA.
- Greenebaum Comprehensive Cancer Center and Center for Stem Cell Biology & Regenerative Medicine, University of Maryland, Baltimore, Baltimore, MD, USA.
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3
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Mousavi R, Lobo D. Automatic design of gene regulatory mechanisms for spatial pattern formation. bioRxiv 2023:2023.07.26.550573. [PMID: 37546866 PMCID: PMC10402059 DOI: 10.1101/2023.07.26.550573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Synthetic developmental biology aims to engineer gene regulatory mechanisms (GRMs) for understanding and producing desired multicellular patterns and shapes. However, designing GRMs for spatial patterns is a current challenge due to the nonlinear interactions and feedback loops in genetic circuits. Here we present a methodology to automatically design GRMs that can produce any given spatial pattern. The proposed approach uses two orthogonal morphogen gradients acting as positional information signals in a multicellular tissue area or culture, which constitutes a continuous field of engineered cells implementing the same designed GRM. To efficiently design both the circuit network and the interaction mechanisms-including the number of genes necessary for the formation of the target pattern-we developed an automated algorithm based on high-performance evolutionary computation. The tolerance of the algorithm can be configured to design GRMs that are either simple to produce approximate patterns or complex to produce precise patterns. We demonstrate the approach by automatically designing GRMs that can produce a diverse set of synthetic spatial expression patterns by interpreting just two orthogonal morphogen gradients. The proposed framework offers a versatile approach to systematically design and discover pattern-producing genetic circuits.
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Affiliation(s)
- Reza Mousavi
- Department of Biological Sciences, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
| | - Daniel Lobo
- Department of Biological Sciences, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
- Greenebaum Comprehensive Cancer Center and Center for Stem Cell Biology & Regenerative Medicine, University of Maryland, School of Medicine, 22 S. Greene Street, Baltimore, MD 21201, USA
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4
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Roy U, Singh D, Vincent N, Haritas CK, Jolly MK. Spatiotemporal Patterning Enabled by Gene Regulatory Networks. ACS Omega 2023; 8:3713-3725. [PMID: 36743018 PMCID: PMC9893257 DOI: 10.1021/acsomega.2c04581] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 11/24/2022] [Indexed: 06/18/2023]
Abstract
Spatiotemporal pattern formation plays a key role in various biological phenomena including embryogenesis and neural network formation. Though the reaction-diffusion systems enabling pattern formation have been studied phenomenologically, the biomolecular mechanisms behind these processes have not been modeled in detail. Here, we study the emergence of spatiotemporal patterns due to simple, synthetic and commonly observed two- and three-node gene regulatory network motifs coupled with their molecular diffusion in one- and two-dimensional space. We investigate the patterns formed due to the coupling of inherent multistable and oscillatory behavior of the toggle switch, toggle switch with double self-activation, toggle triad, and repressilator with the effect of spatial diffusion of these molecules. We probe multiple parameter regimes corresponding to different regions of stability (monostable, multistable, oscillatory) and assess the impact of varying diffusion coefficients. This analysis offers valuable insights into the design principles of pattern formation facilitated by these network motifs, and it suggests the mechanistic underpinnings of biological pattern formation.
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Affiliation(s)
- Ushasi Roy
- Centre
for BioSystems Science and Engineering, Indian Institute of Science, Bangalore560012, India
| | - Divyoj Singh
- Undergraduate
Programme, Indian Institute of Science, Bangalore560012, India
| | - Navin Vincent
- Undergraduate
Programme, Indian Institute of Science, Bangalore560012, India
| | - Chinmay K. Haritas
- Undergraduate
Programme, Indian Institute of Science, Bangalore560012, India
| | - Mohit Kumar Jolly
- Centre
for BioSystems Science and Engineering, Indian Institute of Science, Bangalore560012, India
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5
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Baumschlager A, Rullan M, Khammash M. Exploiting natural chemical photosensitivity of anhydrotetracycline and tetracycline for dynamic and setpoint chemo-optogenetic control. Nat Commun 2020; 11:3834. [PMID: 32737309 PMCID: PMC7395757 DOI: 10.1038/s41467-020-17677-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 07/02/2020] [Indexed: 01/02/2023] Open
Abstract
The transcriptional inducer anhydrotetracycline (aTc) and the bacteriostatic antibiotic tetracycline (Tc) are commonly used in all fields of biology for control of transcription or translation. A drawback of these and other small molecule inducers is the difficulty of their removal from cell cultures, limiting their application for dynamic control. Here, we describe a simple method to overcome this limitation, and show that the natural photosensitivity of aTc/Tc can be exploited to turn them into highly predictable optogenetic transcriptional- and growth-regulators. This new optogenetic class uniquely features both dynamic and setpoint control which act via population-memory adjustable through opto-chemical modulation. We demonstrate this method by applying it for dynamic gene expression control and for enhancing the performance of an existing optogenetic system. We then expand the utility of the aTc system by constructing a new chemical bandpass filter that increases its aTc response range. The simplicity of our method enables scientists and biotechnologists to use their existing systems employing aTc/Tc for dynamic optogenetic experiments without genetic modification.
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Affiliation(s)
- Armin Baumschlager
- Department of Biosystems Science and Engineering (D-BSSE), ETH-Zürich, Mattenstrasse 26, 4058, Basel, Switzerland
| | - Marc Rullan
- Department of Biosystems Science and Engineering (D-BSSE), ETH-Zürich, Mattenstrasse 26, 4058, Basel, Switzerland
| | - Mustafa Khammash
- Department of Biosystems Science and Engineering (D-BSSE), ETH-Zürich, Mattenstrasse 26, 4058, Basel, Switzerland.
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6
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Molinari S, Shis DL, Bhakta SP, Chappell J, Igoshin OA, Bennett MR. A synthetic system for asymmetric cell division in Escherichia coli. Nat Chem Biol 2019; 15:917-924. [PMID: 31406375 PMCID: PMC6702073 DOI: 10.1038/s41589-019-0339-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 07/03/2019] [Indexed: 11/30/2022]
Abstract
We describe a synthetic genetic circuit for controlling asymmetric cell division in E. coli in which a progenitor cell creates a differentiated daughter cell while retaining its original phenotype. Specifically, we engineered an inducible system that can bind and segregate plasmid DNA to a single position in the cell. Upon cell division, co-localized plasmids are kept by one and only one of the daughter cells. The other daughter cell receives no plasmid DNA and is hence irreversibly differentiated from its sibling. In this way, we achieved asymmetric cell division through asymmetric plasmid partitioning. We then used this system to achieve physical separation of genetically distinct cells by tying motility to differentiation. Finally, we characterized an orthogonal inducible circuit that enables the simultaneous asymmetric partitioning of two plasmid species, resulting in cells that have four distinct differentiated states. These results point the way towards engineering multicellular systems from prokaryotic hosts.
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Affiliation(s)
- Sara Molinari
- Department of Biosciences, Rice University, Houston, TX, USA.,PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, USA
| | - David L Shis
- Department of Biosciences, Rice University, Houston, TX, USA
| | - Shyam P Bhakta
- Department of Biosciences, Rice University, Houston, TX, USA.,PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, USA
| | - James Chappell
- Department of Biosciences, Rice University, Houston, TX, USA.,PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, USA
| | - Oleg A Igoshin
- Department of Biosciences, Rice University, Houston, TX, USA.,Department of Bioengineering, Rice University, Houston, TX, USA.,Center for Theoretical Biological Physics, Rice University, Houston, TX, USA
| | - Matthew R Bennett
- Department of Biosciences, Rice University, Houston, TX, USA. .,PhD Program in Systems, Synthetic, and Physical Biology, Rice University, Houston, TX, USA. .,Department of Bioengineering, Rice University, Houston, TX, USA.
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7
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Abstract
Natural biological materials exhibit remarkable properties: self-assembly from simple raw materials, precise control of morphology, diverse physical and chemical properties, self-repair, and the ability to sense-and-respond to environmental stimuli. Despite having found numerous uses in human industry and society, the utility of natural biological materials is limited. But, could it be possible to genetically program microbes to create entirely new and useful biological materials? At the intersection between microbiology, material science, and synthetic biology, the emerging field of biological engineered living materials (ELMs) aims to answer this question. Here we review recent efforts to program cells to produce living materials with novel functional properties, focusing on microbial systems that can be engineered to grow materials and on new genetic circuits for pattern formation that could be used to produce the more complex systems of the future.
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Affiliation(s)
- Charlie Gilbert
- Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, U.K
- Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
| | - Tom Ellis
- Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, U.K
- Department of Bioengineering, Imperial College London, London SW7 2AZ, U.K
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8
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Brechun KE, Arndt KM, Woolley GA. Selection of Protein-Protein Interactions of Desired Affinities with a Bandpass Circuit. J Mol Biol 2019; 431:391-400. [PMID: 30448232 DOI: 10.1016/j.jmb.2018.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/07/2018] [Accepted: 11/08/2018] [Indexed: 11/17/2022]
Abstract
We have developed a genetic circuit in Escherichia coli that can be used to select for protein-protein interactions of different strengths by changing antibiotic concentrations in the media. The genetic circuit links protein-protein interaction strength to β-lactamase activity while simultaneously imposing tuneable positive and negative selection pressure for β-lactamase activity. Cells only survive if they express interacting proteins with affinities that fall within set high- and low-pass thresholds; i.e. the circuit therefore acts as a bandpass filter for protein-protein interactions. We show that the circuit can be used to recover protein-protein interactions of desired affinity from a mixed population with a range of affinities. The circuit can also be used to select for inhibitors of protein-protein interactions of defined strength.
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Affiliation(s)
- Katherine E Brechun
- Department of Chemistry, University of Toronto, Toronto, Canada; Molecular Biotechnology, University of Potsdam, Potsdam, Germany
| | - Katja M Arndt
- Molecular Biotechnology, University of Potsdam, Potsdam, Germany.
| | - G Andrew Woolley
- Department of Chemistry, University of Toronto, Toronto, Canada.
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9
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Santos‐Moreno J, Schaerli Y. Using Synthetic Biology to Engineer Spatial Patterns. ACTA ACUST UNITED AC 2018; 3:e1800280. [DOI: 10.1002/adbi.201800280] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/14/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Javier Santos‐Moreno
- Department of Fundamental MicrobiologyUniversity of LausanneBiophore Building 1015 Lausanne Switzerland
| | - Yolanda Schaerli
- Department of Fundamental MicrobiologyUniversity of LausanneBiophore Building 1015 Lausanne Switzerland
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10
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Abstract
Modern genetic tools allow the dissection and emulation of fundamental mechanisms shaping morphogenesis in multicellular organisms. Several synthetic genetic circuits for control of multicellular patterning have been reported to date. However, hierarchical induction of gene expression domains has received little attention from synthetic biologists, despite its importance in biological self-organization. Here we report a synthetic genetic system implementing population-based AND-logic for programmed autonomous induction of bacterial gene expression domains. We develop a ratiometric assay for bacteriophage T7 RNA polymerase activity and use it to systematically characterize different intact and split enzyme variants. We then utilize the best-performing variant to build a three-color patterning system responsive to two different homoserine lactones. We validate the AND gate-like behavior of this system both in cell suspension and in surface culture. Finally, we use the synthetic circuit in a membrane-based spatial assay to demonstrate programmed hierarchical patterning of gene expression across bacterial populations.
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Affiliation(s)
- Christian R Boehm
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, 14476, Potsdam, Germany
| | - Paul K Grant
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK
- Microsoft Research, 21 Station Road, Cambridge, CB1 2FB, UK
| | - Jim Haseloff
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EA, UK.
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11
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Abstract
Synthesizing spatial patterns with genetic networks is an ongoing challenge in synthetic biology. A successful demonstration of pattern formation would imply a better understanding of systems in the natural world and advance applications in synthetic biology. In developmental systems, transient patterning may suffice in order to imprint instructions for long-term development. In this paper we show that transient but persistent patterns can emerge from a realizable synthetic gene network based on a toggle switch. We show that a bistable system incorporating diffusible molecules can generate patterns that resemble Turing patterns but are distinctly different in the underlying mechanism: diffusion of mutually inhibiting molecules creates a prolonged "tug-of-war" between patches of cells at opposing bistable states. The patterns are transient but longer wavelength patterns persist for extended periods of time. Analysis of a representative small scale model implies the eigenvalues of the persistent modes are just above the threshold of stability. The results are verified through simulation of biologically relevant models.
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Affiliation(s)
- Marcella M. Gomez
- Electrical Engineering and Computer Sciences, UC Berkeley, Berkeley, CA, USA
| | - Murat Arcak
- Electrical Engineering and Computer Sciences, UC Berkeley, Berkeley, CA, USA
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12
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Scholes NS, Isalan M. A three-step framework for programming pattern formation. Curr Opin Chem Biol 2017; 40:1-7. [DOI: 10.1016/j.cbpa.2017.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/24/2017] [Accepted: 04/10/2017] [Indexed: 12/31/2022]
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13
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Hsu CY, Pan ZM, Hu RH, Chang CC, Cheng HC, Lin C, Chen BS. Systematic Biological Filter Design with a Desired I/O Filtering Response Based on Promoter-RBS Libraries. IEEE/ACM Trans Comput Biol Bioinform 2015; 12:712-725. [PMID: 26357282 DOI: 10.1109/tcbb.2014.2372790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this study, robust biological filters with an external control to match a desired input/output (I/O) filtering response are engineered based on the well-characterized promoter-RBS libraries and a cascade gene circuit topology. In the field of synthetic biology, the biological filter system serves as a powerful detector or sensor to sense different molecular signals and produces a specific output response only if the concentration of the input molecular signal is higher or lower than a specified threshold. The proposed systematic design method of robust biological filters is summarized into three steps. Firstly, several well-characterized promoter-RBS libraries are established for biological filter design by identifying and collecting the quantitative and qualitative characteristics of their promoter-RBS components via nonlinear parameter estimation method. Then, the topology of synthetic biological filter is decomposed into three cascade gene regulatory modules, and an appropriate promoter-RBS library is selected for each module to achieve the desired I/O specification of a biological filter. Finally, based on the proposed systematic method, a robust externally tunable biological filter is engineered by searching the promoter-RBS component libraries and a control inducer concentration library to achieve the optimal reference match for the specified I/O filtering response.
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14
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Heng BC, Aubel D, Fussenegger M. Prosthetic gene networks as an alternative to standard pharmacotherapies for metabolic disorders. Curr Opin Biotechnol 2015; 35:37-45. [PMID: 25679308 DOI: 10.1016/j.copbio.2015.01.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 01/28/2015] [Accepted: 01/28/2015] [Indexed: 12/19/2022]
Abstract
Synthetic biology makes inroads into clinical therapy with the debut of closed-loop prosthetic gene networks specifically designed to treat human diseases. Prosthetic networks are synthetic sensor/effector devices that could functionally integrate and interface with host metabolism to monitor disease states and coordinate appropriate therapeutic responses in a self-sufficient, timely and automatic manner. Prosthetic networks hold particular promise for the current global epidemic of closely interrelated metabolic disorders encompassing obesity, type 2 diabetes, hypertension and hyperlipidaemia, which arise from the unhealthy lifestyle and dietary factors in the modern urbanised world. This review will critically examine the various attempts at constructing prosthetic gene networks for the treatment of these metabolic disorders, as well as provide insight into future developments in the field.
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Affiliation(s)
- Boon Chin Heng
- Department of Biological Sciences, Sunway University, Bandar Sunway 47500, Selangor Darul Ehsan, Malaysia; Department of Biosystems Science and Engineering (D-BSSE), ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland
| | - Dominique Aubel
- IUTA Département Génie Biologique, Université Claude Bernard Lyon 1, Boulevard du 11 Novembre 1918, F-69622 Villeurbanne Cedex, France
| | - Martin Fussenegger
- Department of Biosystems Science and Engineering (D-BSSE), ETH Zurich, Mattenstrasse 26, CH-4058 Basel, Switzerland; Faculty of Science, University of Basel, Mattenstrasse 26, CH-4058 Basel, Switzerland.
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15
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Abstract
Synthetic biology has developed numerous parts for building synthetic gene circuits. However, few parts have been described for prokaryotes to integrate two signals at a promoter in an AND fashion, i.e. the promoter is only activated in the presence of both signals. Here we present a new part for this function: a split intein T7 RNA polymerase. We divide T7 RNA polymerase into two expression domains and fuse each to a split intein. Only when both domains are expressed does the split intein mediate protein trans-splicing, yielding a full-length T7 RNA polymerase that can transcribe genes via a T7 promoter. We demonstrate an AND gate with the new part: the signal-to-background ratio is very high, resulting in an almost digital signal. This has utility for more complex circuits and so we construct a band-pass filter in Escherichia coli. The split intein approach should be widely applicable for engineering artificial gene circuit parts.
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Affiliation(s)
- Yolanda Schaerli
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Magüi Gili
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Mark Isalan
- EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain Universitat Pompeu Fabra (UPF), Barcelona, Spain Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
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16
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Schaerli Y, Munteanu A, Gili M, Cotterell J, Sharpe J, Isalan M. A unified design space of synthetic stripe-forming networks. Nat Commun 2014; 5:4905. [PMID: 25247316 PMCID: PMC4172969 DOI: 10.1038/ncomms5905] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 08/02/2014] [Indexed: 12/11/2022] Open
Abstract
Synthetic biology is a promising tool to study the function and properties of gene regulatory networks. Gene circuits with predefined behaviours have been successfully built and modelled, but largely on a case-by-case basis. Here we go beyond individual networks and explore both computationally and synthetically the design space of possible dynamical mechanisms for 3-node stripe-forming networks. First, we computationally test every possible 3-node network for stripe formation in a morphogen gradient. We discover four different dynamical mechanisms to form a stripe and identify the minimal network of each group. Next, with the help of newly established engineering criteria we build these four networks synthetically and show that they indeed operate with four fundamentally distinct mechanisms. Finally, this close match between theory and experiment allows us to infer and subsequently build a 2-node network that represents the archetype of the explored design space.
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Affiliation(s)
- Yolanda Schaerli
- 1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Andreea Munteanu
- 1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Magüi Gili
- 1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - James Cotterell
- 1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - James Sharpe
- 1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Barcelona, Spain [3] Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, 08010 Barcelona, Spain
| | - Mark Isalan
- 1] EMBL/CRG Systems Biology Research Unit, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain [2] Universitat Pompeu Fabra (UPF), Barcelona, Spain [3] Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
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17
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Hsia J, Holtz WJ, Huang DC, Arcak M, Maharbiz MM. A feedback quenched oscillator produces turing patterning with one diffuser. PLoS Comput Biol 2012; 8:e1002331. [PMID: 22291582 PMCID: PMC3266880 DOI: 10.1371/journal.pcbi.1002331] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Accepted: 11/14/2011] [Indexed: 11/18/2022] Open
Abstract
Efforts to engineer synthetic gene networks that spontaneously produce patterning in multicellular ensembles have focused on Turing's original model and the "activator-inhibitor" models of Meinhardt and Gierer. Systems based on this model are notoriously difficult to engineer. We present the first demonstration that Turing pattern formation can arise in a new family of oscillator-driven gene network topologies, specifically when a second feedback loop is introduced which quenches oscillations and incorporates a diffusible molecule. We provide an analysis of the system that predicts the range of kinetic parameters over which patterning should emerge and demonstrate the system's viability using stochastic simulations of a field of cells using realistic parameters. The primary goal of this paper is to provide a circuit architecture which can be implemented with relative ease by practitioners and which could serve as a model system for pattern generation in synthetic multicellular systems. Given the wide range of oscillatory circuits in natural systems, our system supports the tantalizing possibility that Turing pattern formation in natural multicellular systems can arise from oscillator-driven mechanisms.
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Affiliation(s)
- Justin Hsia
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California, United States of America.
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18
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Abstract
A major focus in synthetic biology is the rational design and implementation of gene circuits to control dynamics of individual cells and, increasingly, cellular populations. Population-level control is highlighted in recent studies which attempt to design and implement synthetic ecosystems (or engineered microbial consortia). On the one hand, these engineered systems may serve as a critical technological foundation for practical applications. On the other hand, they may serve as well-defined model systems to examine biological questions of broad relevance. Here, using a synthetic predator-prey ecosystem as an example, we illustrate the basic experimental techniques involved in system implementation and characterization. By extension, these techniques are applicable to the analysis of other microbial-based synthetic or natural ecosystems.
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Affiliation(s)
- Stephen Payne
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
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19
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20
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Muranaka N, Yokobayashi Y. Posttranscriptional Signal Integration of Engineered Riboswitches Yields Band-Pass Output. Angew Chem Int Ed Engl 2010; 49:4653-5. [DOI: 10.1002/anie.201001482] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Pai A, Tanouchi Y, Collins CH, You L. Engineering multicellular systems by cell-cell communication. Curr Opin Biotechnol 2009; 20:461-70. [PMID: 19733047 DOI: 10.1016/j.copbio.2009.08.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Revised: 08/07/2009] [Accepted: 08/12/2009] [Indexed: 11/23/2022]
Abstract
Synthetic biology encompasses the design of new biological parts and systems as well as the modulation of existing biological networks to generate novel functions. In recent years, increasing emphasis has been placed on the engineering of population-level behaviors using cell-cell communication. From the engineering perspective, cell-cell communication serves as a versatile regulatory module that enables coordination among cells in and between populations and facilitates the generation of reliable dynamics. In addition to exploring biological 'design principles' via the construction of increasingly complex dynamics, communication-based synthetic systems can be used as well-defined model systems to study ecological and social interactions such as competition, cooperation, and predation. Here we discuss the dynamic properties of cell-cell communication modules, how they can be engineered for synthetic circuit design, and applications of these systems.
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