1
|
Yao HT, Marchand B, Berkemer SJ, Ponty Y, Will S. Infrared: a declarative tree decomposition-powered framework for bioinformatics. Algorithms Mol Biol 2024; 19:13. [PMID: 38493130 PMCID: PMC10943887 DOI: 10.1186/s13015-024-00258-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 02/13/2024] [Indexed: 03/18/2024] Open
Abstract
MOTIVATION Many bioinformatics problems can be approached as optimization or controlled sampling tasks, and solved exactly and efficiently using Dynamic Programming (DP). However, such exact methods are typically tailored towards specific settings, complex to develop, and hard to implement and adapt to problem variations. METHODS We introduce the Infrared framework to overcome such hindrances for a large class of problems. Its underlying paradigm is tailored toward problems that can be declaratively formalized as sparse feature networks, a generalization of constraint networks. Classic Boolean constraints specify a search space, consisting of putative solutions whose evaluation is performed through a combination of features. Problems are then solved using generic cluster tree elimination algorithms over a tree decomposition of the feature network. Their overall complexities are linear on the number of variables, and only exponential in the treewidth of the feature network. For sparse feature networks, associated with low to moderate treewidths, these algorithms allow to find optimal solutions, or generate controlled samples, with practical empirical efficiency. RESULTS Implementing these methods, the Infrared software allows Python programmers to rapidly develop exact optimization and sampling applications based on a tree decomposition-based efficient processing. Instead of directly coding specialized algorithms, problems are declaratively modeled as sets of variables over finite domains, whose dependencies are captured by constraints and functions. Such models are then automatically solved by generic DP algorithms. To illustrate the applicability of Infrared in bioinformatics and guide new users, we model and discuss variants of bioinformatics applications. We provide reimplementations and extensions of methods for RNA design, RNA sequence-structure alignment, parsimony-driven inference of ancestral traits in phylogenetic trees/networks, and design of coding sequences. Moreover, we demonstrate multidimensional Boltzmann sampling. These applications of the framework-together with our novel results-underline the practical relevance of Infrared. Remarkably, the achieved complexities are typically equivalent to the ones of specialized algorithms and implementations. AVAILABILITY Infrared is available at https://amibio.gitlabpages.inria.fr/Infrared with extensive documentation, including various usage examples and API reference; it can be installed using Conda or from source.
Collapse
Affiliation(s)
- Hua-Ting Yao
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France.
- Department of Theoretical Chemistry, University of Vienna, Vienna, Austria.
- School of Computer Science, McGill University, Montreal, Canada.
| | - Bertrand Marchand
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
| | - Sarah J Berkemer
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Yann Ponty
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
| | - Sebastian Will
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France.
| |
Collapse
|
2
|
Yao HT, Ponty Y, Will S. Developing Complex RNA Design Applications in the Infrared Framework. Methods Mol Biol 2024; 2726:285-313. [PMID: 38780736 DOI: 10.1007/978-1-0716-3519-3_12] [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: 05/25/2024]
Abstract
Applications in biotechnology and bio-medical research call for effective strategies to design novel RNAs with very specific properties. Such advanced design tasks require support by computational tools but at the same time put high demands on their flexibility and expressivity to model the application-specific requirements. To address such demands, we present the computational framework Infrared. It supports developing advanced customized design tools, which generate RNA sequences with specific properties, often in a few lines of Python code. This text guides the reader in tutorial format through the development of complex design applications. Thanks to the declarative, compositional approach of Infrared, we can describe this development as a step-by-step extension of an elementary design task. Thus, we start with generating sequences that are compatible with a single RNA structure and go all the way to RNA design targeting complex positive and negative design objectives with respect to single or even multiple target structures. Finally, we present a "real-world" application of computational design to create an RNA device for biotechnology: we use Infrared to generate design candidates of an artificial "AND" riboswitch, which activates gene expression in the simultaneous presence of two different small metabolites. In these applications, we exploit that the system can generate, in an efficient (fixed-parameter tractable) way, multiple diverse designs that satisfy a number of constraints and have high quality w.r.t. to an objective (by sampling from a Boltzmann distribution).
Collapse
Affiliation(s)
- Hua-Ting Yao
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
- School of Computer Science, McGill University, Montreal, Canada
- Department of Theoretical Chemistry, University of Vienna, Vienna, Austria
| | - Yann Ponty
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France
| | - Sebastian Will
- LIX, CNRS UMR 7161, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France.
| |
Collapse
|
3
|
Ender A, Stadler PF, Mörl M, Findeiß S. RNA Design Principles for Riboswitches that Regulate RNase P-Mediated tRNA Processing. Methods Mol Biol 2022; 2518:179-202. [PMID: 35666446 DOI: 10.1007/978-1-0716-2421-0_11] [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: 06/15/2023]
Abstract
Riboswitches are an attractive target for the directed design of RNA-based regulators by in silico prediction. These noncoding RNA elements consist of an aptamer platform for the highly selective ligand recognition and an expression platform which controls gene activity typically at the level of transcription or translation. In previous work, we could successfully apply RNA folding prediction to implement a new riboswitch mechanism regulating processing of a tRNA by RNase P. In this contribution, we present detailed information about our pipeline consisting of in silico design combined with the biochemical analysis for the verification of the implemented mechanism. Furthermore, we discuss the applicability of the presented biochemical in vivo and in vitro methods for the characterization of other artificial riboswitches.
Collapse
Affiliation(s)
- Anna Ender
- Institute for Biochemistry, Leipzig University, Leipzig, Germany
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, Leipzig University, Leipzig, Germany
- Max Planck Institute for Mathematics in the Science, Leipzig, Germany
- Institute for Theoretical Chemistry, University of Vienna, Vienna, Austria
- Santa Fe Institute, Santa Fe, NM, USA
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University, Leipzig, Germany
| | - Sven Findeiß
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, Leipzig University, Leipzig, Germany.
| |
Collapse
|
4
|
Advanced Design of Structural RNAs Using RNARedPrint. Methods Mol Biol 2021. [PMID: 33835434 DOI: 10.1007/978-1-0716-1307-8_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
RNA design addresses the need to build novel RNAs, e.g., for biotechnological applications in synthetic biology, equipped with desired functional properties. This chapter describes how to use the software RNARedPrint for the de novo rational design of RNA sequences adopting one or several desired secondary structures. Depending on the application, these structures could represent alternate configurations or kinetic pathways. The software makes such design convenient and sufficiently fast for practical routine, where it even overcomes notorious problems in the application of RNA design, e.g., it maintains realistic GC content.
Collapse
|
5
|
Huang FW, Barrett CL, Reidys CM. The energy-spectrum of bicompatible sequences. Algorithms Mol Biol 2021; 16:7. [PMID: 34074304 PMCID: PMC8167974 DOI: 10.1186/s13015-021-00187-4] [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: 10/28/2020] [Accepted: 05/24/2021] [Indexed: 12/04/2022] Open
Abstract
Background Genotype-phenotype maps provide a meaningful filtration of sequence space and RNA secondary structures are particular such phenotypes. Compatible sequences, which satisfy the base-pairing constraints of a given RNA structure, play an important role in the context of neutral evolution. Sequences that are simultaneously compatible with two given structures (bicompatible sequences), are beacons in phenotypic transitions, induced by erroneously replicating populations of RNA sequences. RNA riboswitches, which are capable of expressing two distinct secondary structures without changing the underlying sequence, are one example of bicompatible sequences in living organisms. Results We present a full loop energy model Boltzmann sampler of bicompatible sequences for pairs of structures. The sequence sampler employs a dynamic programming routine whose time complexity is polynomial when assuming the maximum number of exposed vertices, \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\kappa $$\end{document}κ, is a constant. The parameter \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\kappa $$\end{document}κ depends on the two structures and can be very large. We introduce a novel topological framework encapsulating the relations between loops that sheds light on the understanding of \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\kappa $$\end{document}κ. Based on this framework, we give an algorithm to sample sequences with minimum \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$\kappa $$\end{document}κ on a particular topologically classified case as well as giving hints to the solution in the other cases. As a result, we utilize our sequence sampler to study some established riboswitches. Conclusion Our analysis of riboswitch sequences shows that a pair of structures needs to satisfy key properties in order to facilitate phenotypic transitions and that pairs of random structures are unlikely to do so. Our analysis observes a distinct signature of riboswitch sequences, suggesting a new criterion for identifying native sequences and sequences subjected to evolutionary pressure. Our free software is available at: https://github.com/FenixHuang667/Bifold.
Collapse
|
6
|
Ender A, Etzel M, Hammer S, Findeiß S, Stadler P, Mörl M. Ligand-dependent tRNA processing by a rationally designed RNase P riboswitch. Nucleic Acids Res 2021; 49:1784-1800. [PMID: 33469651 PMCID: PMC7897497 DOI: 10.1093/nar/gkaa1282] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 12/21/2020] [Accepted: 12/29/2020] [Indexed: 11/29/2022] Open
Abstract
We describe a synthetic riboswitch element that implements a regulatory principle which directly addresses an essential tRNA maturation step. Constructed using a rational in silico design approach, this riboswitch regulates RNase P-catalyzed tRNA 5′-processing by either sequestering or exposing the single-stranded 5′-leader region of the tRNA precursor in response to a ligand. A single base pair in the 5′-leader defines the regulatory potential of the riboswitch both in vitro and in vivo. Our data provide proof for prior postulates on the importance of the structure of the leader region for tRNA maturation. We demonstrate that computational predictions of ligand-dependent structural rearrangements can address individual maturation steps of stable non-coding RNAs, thus making them amenable as promising target for regulatory devices that can be used as functional building blocks in synthetic biology.
Collapse
Affiliation(s)
- Anna Ender
- Institute for Biochemistry, Leipzig University, Brüderstr. 34, 04103 Leipzig, Germany
| | - Maja Etzel
- Institute for Biochemistry, Leipzig University, Brüderstr. 34, 04103 Leipzig, Germany
| | - Stefan Hammer
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, Leipzig University, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Sven Findeiß
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, Leipzig University, Härtelstr. 16-18, 04107 Leipzig, Germany
| | - Peter Stadler
- Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, Leipzig University, Härtelstr. 16-18, 04107 Leipzig, Germany.,Max Planck Institute for Mathematics in the Science, Inselstr. 22, 04103 Leipzig, Germany.,Institute for Theoretical Chemistry, University of Vienna, Währingerstr. 17, A-1090 Vienna, Austria.,Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University, Brüderstr. 34, 04103 Leipzig, Germany
| |
Collapse
|
7
|
Harima H, Orba Y, Torii S, Qiu Y, Kajihara M, Eto Y, Matsuta N, Hang'ombe BM, Eshita Y, Uemura K, Matsuno K, Sasaki M, Yoshii K, Nakao R, Hall WW, Takada A, Abe T, Wolfinger MT, Simuunza M, Sawa H. An African tick flavivirus forming an independent clade exhibits unique exoribonuclease-resistant RNA structures in the genomic 3'-untranslated region. Sci Rep 2021; 11:4883. [PMID: 33649491 PMCID: PMC7921595 DOI: 10.1038/s41598-021-84365-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 02/15/2021] [Indexed: 12/16/2022] Open
Abstract
Tick-borne flaviviruses (TBFVs) infect mammalian hosts through tick bites and can cause various serious illnesses, such as encephalitis and hemorrhagic fevers, both in humans and animals. Despite their importance to public health, there is limited epidemiological information on TBFV infection in Africa. Herein, we report that a novel flavivirus, Mpulungu flavivirus (MPFV), was discovered in a Rhipicephalus muhsamae tick in Zambia. MPFV was found to be genetically related to Ngoye virus detected in ticks in Senegal, and these viruses formed a unique lineage in the genus Flavivirus. Analyses of dinucleotide contents of flaviviruses indicated that MPFV was similar to those of other TBFVs with a typical vertebrate genome signature, suggesting that MPFV may infect vertebrate hosts. Bioinformatic analyses of the secondary structures in the 3′-untranslated regions (UTRs) revealed that MPFV exhibited unique exoribonuclease-resistant RNA (xrRNA) structures. Utilizing biochemical approaches, we clarified that two xrRNA structures of MPFV in the 3′-UTR could prevent exoribonuclease activity. In summary, our findings provide new information regarding the geographical distribution of TBFV and xrRNA structures in the 3′-UTR of flaviviruses.
Collapse
Affiliation(s)
- Hayato Harima
- Hokudai Center for Zoonosis Control in Zambia, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Yasuko Orba
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Shiho Torii
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Yongjin Qiu
- Hokudai Center for Zoonosis Control in Zambia, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Masahiro Kajihara
- Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Yoshiki Eto
- Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Naoya Matsuta
- Department of Electrical and Information Engineering, Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Bernard M Hang'ombe
- Department of Para-Clinical Studies, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia.,Africa Center of Excellence for Infectious Diseases of Humans and Animals, The University of Zambia, Lusaka, Zambia
| | - Yuki Eshita
- Hokudai Center for Zoonosis Control in Zambia, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Kentaro Uemura
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Drug Discovery and Disease Research Laboratory, Shionogi & Co., Ltd., Osaka, Japan
| | - Keita Matsuno
- International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Unit of Risk Analysis and Management, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Michihito Sasaki
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan
| | - Kentaro Yoshii
- Laboratory of Public Health, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.,National Research Center for the Control and Prevention of Infectious Diseases (CCPID), Nagasaki University, Nagasaki, Japan
| | - Ryo Nakao
- Laboratory of Parasitology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - William W Hall
- International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,National Virus Reference Laboratory, School of Medicine, University College Dublin, Dublin, Ireland.,Centre for Research in Infectious Diseases, School of Medicine, University College Dublin, Dublin, Ireland.,Global Virus Network, Baltimore, MD, USA
| | - Ayato Takada
- International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Division of Global Epidemiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.,Africa Center of Excellence for Infectious Diseases of Humans and Animals, The University of Zambia, Lusaka, Zambia.,Department of Disease Control, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
| | - Takashi Abe
- Department of Electrical and Information Engineering, Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Michael T Wolfinger
- Department of Theoretical Chemistry, University of Vienna, Vienna, Austria.,Research Group Bioinformatics and Computational Biology, Faculty of Computer Science, University of Vienna, Vienna, Austria
| | - Martin Simuunza
- Africa Center of Excellence for Infectious Diseases of Humans and Animals, The University of Zambia, Lusaka, Zambia.,Department of Disease Control, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia
| | - Hirofumi Sawa
- Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan. .,International Collaboration Unit, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan. .,Africa Center of Excellence for Infectious Diseases of Humans and Animals, The University of Zambia, Lusaka, Zambia. .,Global Virus Network, Baltimore, MD, USA. .,Department of Disease Control, School of Veterinary Medicine, The University of Zambia, Lusaka, Zambia.
| |
Collapse
|
8
|
Retwitzer MD, Reinharz V, Churkin A, Ponty Y, Waldispühl J, Barash D. incaRNAfbinv 2.0: a webserver and software with motif control for fragment-based design of RNAs. Bioinformatics 2020; 36:2920-2922. [PMID: 31971575 DOI: 10.1093/bioinformatics/btaa039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 11/25/2019] [Accepted: 01/15/2020] [Indexed: 11/12/2022] Open
Abstract
SUMMARY RNA design has conceptually evolved from the inverse RNA folding problem. In the classical inverse RNA problem, the user inputs an RNA secondary structure and receives an output RNA sequence that folds into it. Although modern RNA design methods are based on the same principle, a finer control over the resulting sequences is sought. As an important example, a substantial number of non-coding RNA families show high preservation in specific regions, while being more flexible in others and this information should be utilized in the design. By using the additional information, RNA design tools can help solve problems of practical interest in the growing fields of synthetic biology and nanotechnology. incaRNAfbinv 2.0 utilizes a fragment-based approach, enabling a control of specific RNA secondary structure motifs. The new version allows significantly more control over the general RNA shape, and also allows to express specific restrictions over each motif separately, in addition to other advanced features. AVAILABILITY AND IMPLEMENTATION incaRNAfbinv 2.0 is available through a standalone package and a web-server at https://www.cs.bgu.ac.il/incaRNAfbinv. Source code, command-line and GUI wrappers can be found at https://github.com/matandro/RNAsfbinv. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Matan Drory Retwitzer
- Department of Computer Science, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| | - Vladimir Reinharz
- Department of Computer Science, Université du Québec à Montréal, Montreal, H2X 3Y7, Canada.,Institute for Basic Science, Daejeon 34126, South Korea
| | - Alexander Churkin
- Software Engineering Department, Sami Shamoon College of Engineering, Beer-Sheva 84100, Israel
| | - Yann Ponty
- Laboratoire d'Informatique de l'École Polytechnique (LIX CNRS UMR 7161), Ecole Polytechnique, Palaiseau 91120, France
| | - Jérôme Waldispühl
- School of Computer Science, McGill University Montréal H3A 0E9, Canada
| | - Danny Barash
- Department of Computer Science, Ben Gurion University of the Negev, Beer Sheva 84105, Israel
| |
Collapse
|
9
|
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.
Collapse
|
10
|
Hammer S, Wang W, Will S, Ponty Y. Fixed-parameter tractable sampling for RNA design with multiple target structures. BMC Bioinformatics 2019; 20:209. [PMID: 31023239 PMCID: PMC6482512 DOI: 10.1186/s12859-019-2784-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 03/28/2019] [Indexed: 01/09/2023] Open
Abstract
Background The design of multi-stable RNA molecules has important applications in biology, medicine, and biotechnology. Synthetic design approaches profit strongly from effective in-silico methods, which substantially reduce the need for costly wet-lab experiments. Results We devise a novel approach to a central ingredient of most in-silico design methods: the generation of sequences that fold well into multiple target structures. Based on constraint networks, our approach supports generic Boltzmann-weighted sampling, which enables the positive design of RNA sequences with specific free energies (for each of multiple, possibly pseudoknotted, target structures) and GC-content. Moreover, we study general properties of our approach empirically and generate biologically relevant multi-target Boltzmann-weighted designs for an established design benchmark. Our results demonstrate the efficacy and feasibility of the method in practice as well as the benefits of Boltzmann sampling over the previously best multi-target sampling strategy—even for the case of negative design of multi-stable RNAs. Besides empirically studies, we finally justify the algorithmic details due to a fundamental theoretic result about multi-stable RNA design, namely the #P-hardness of the counting of designs. Conclusion introduces a novel, flexible, and effective approach to multi-target RNA design, which promises broad applicability and extensibility. Our free software is available at: https://github.com/yannponty/RNARedPrint
Supplementary data are available online. Electronic supplementary material The online version of this article (10.1186/s12859-019-2784-7) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Stefan Hammer
- Dept. Computer Science, and Interdisciplinary Center for Bioinformatics, Univ. Leipzig, Härtelstr. 16-18, Leipzig, D-04107, Germany.,Dept. Theoretical Chemistry, Univ. Vienna, Währingerstr. 17, Wien, A-1090, Austria.,Bioinformatics and Computational Biology Research Group, Univ. Vienna, Währingerstr. 17, Wien, A-1090, Austria
| | - Wei Wang
- CNRS UMR 7161 LIX, Ecole Polytechnique, Bat. Alan Turing, Palaiseau, 91120, France
| | - Sebastian Will
- Dept. Theoretical Chemistry, Univ. Vienna, Währingerstr. 17, Wien, A-1090, Austria. .,Bioinformatics and Computational Biology Research Group, Univ. Vienna, Währingerstr. 17, Wien, A-1090, Austria.
| | - Yann Ponty
- CNRS UMR 7161 LIX, Ecole Polytechnique, Bat. Alan Turing, Palaiseau, 91120, France.
| |
Collapse
|
11
|
Efficient computation of co-transcriptional RNA-ligand interaction dynamics. Methods 2018; 143:70-76. [PMID: 29730250 DOI: 10.1016/j.ymeth.2018.04.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 04/26/2018] [Accepted: 04/29/2018] [Indexed: 11/23/2022] Open
Abstract
Riboswitches form an abundant class of cis-regulatory RNA elements that mediate gene expression by binding a small metabolite. For synthetic biology applications, they are becoming cheap and accessible systems for selectively triggering transcription or translation of downstream genes. Many riboswitches are kinetically controlled, hence knowledge of their co-transcriptional mechanisms is essential. We present here an efficient implementation for analyzing co-transcriptional RNA-ligand interaction dynamics. This approach allows for the first time to model concentration-dependent metabolite binding/unbinding kinetics. We exemplify this novel approach by means of the recently studied I-A 2'-deoxyguanosine (2'dG)-sensing riboswitch from Mesoplasma florum.
Collapse
|
12
|
Findeiß S, Hammer S, Wolfinger MT, Kühnl F, Flamm C, Hofacker IL. In silico design of ligand triggered RNA switches. Methods 2018; 143:90-101. [PMID: 29660485 DOI: 10.1016/j.ymeth.2018.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/06/2018] [Accepted: 04/06/2018] [Indexed: 02/06/2023] Open
Abstract
This contribution sketches a work flow to design an RNA switch that is able to adapt two structural conformations in a ligand-dependent way. A well characterized RNA aptamer, i.e., knowing its Kd and adaptive structural features, is an essential ingredient of the described design process. We exemplify the principles using the well-known theophylline aptamer throughout this work. The aptamer in its ligand-binding competent structure represents one structural conformation of the switch while an alternative fold that disrupts the binding-competent structure forms the other conformation. To keep it simple we do not incorporate any regulatory mechanism to control transcription or translation. We elucidate a commonly used design process by explicitly dissecting and explaining the necessary steps in detail. We developed a novel objective function which specifies the mechanistics of this simple, ligand-triggered riboswitch and describe an extensive in silico analysis pipeline to evaluate important kinetic properties of the designed sequences. This protocol and the developed software can be easily extended or adapted to fit novel design scenarios and thus can serve as a template for future needs.
Collapse
Affiliation(s)
- Sven Findeiß
- Bioinformatics, Institute of Computer Science, and Interdisciplinary Center for Bioinformatics, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany; University of Vienna, Faculty of Computer Science, Research Group Bioinformatics and Computational Biology, Währingerstraße 29, 1090 Vienna, Austria; University of Vienna, Faculty of Chemistry, Department of Theoretical Chemistry, Währingerstraße 17, 1090 Vienna, Austria.
| | - Stefan Hammer
- Bioinformatics, Institute of Computer Science, and Interdisciplinary Center for Bioinformatics, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany; University of Vienna, Faculty of Computer Science, Research Group Bioinformatics and Computational Biology, Währingerstraße 29, 1090 Vienna, Austria; University of Vienna, Faculty of Chemistry, Department of Theoretical Chemistry, Währingerstraße 17, 1090 Vienna, Austria
| | - Michael T Wolfinger
- University of Vienna, Faculty of Chemistry, Department of Theoretical Chemistry, Währingerstraße 17, 1090 Vienna, Austria; Medical University of Vienna, Center for Anatomy and Cell Biology, Währingerstraße 13, 1090 Vienna, Austria
| | - Felix Kühnl
- Bioinformatics, Institute of Computer Science, and Interdisciplinary Center for Bioinformatics, Leipzig University, Härtelstraße 16-18, 04107 Leipzig, Germany
| | - Christoph Flamm
- University of Vienna, Faculty of Chemistry, Department of Theoretical Chemistry, Währingerstraße 17, 1090 Vienna, Austria
| | - Ivo L Hofacker
- University of Vienna, Faculty of Computer Science, Research Group Bioinformatics and Computational Biology, Währingerstraße 29, 1090 Vienna, Austria; University of Vienna, Faculty of Chemistry, Department of Theoretical Chemistry, Währingerstraße 17, 1090 Vienna, Austria
| |
Collapse
|
13
|
Findeiß S, Etzel M, Will S, Mörl M, Stadler PF. Design of Artificial Riboswitches as Biosensors. SENSORS 2017; 17:s17091990. [PMID: 28867802 PMCID: PMC5621056 DOI: 10.3390/s17091990] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 08/23/2017] [Accepted: 08/25/2017] [Indexed: 12/11/2022]
Abstract
RNA aptamers readily recognize small organic molecules, polypeptides, as well as other nucleic acids in a highly specific manner. Many such aptamers have evolved as parts of regulatory systems in nature. Experimental selection techniques such as SELEX have been very successful in finding artificial aptamers for a wide variety of natural and synthetic ligands. Changes in structure and/or stability of aptamers upon ligand binding can propagate through larger RNA constructs and cause specific structural changes at distal positions. In turn, these may affect transcription, translation, splicing, or binding events. The RNA secondary structure model realistically describes both thermodynamic and kinetic aspects of RNA structure formation and refolding at a single, consistent level of modelling. Thus, this framework allows studying the function of natural riboswitches in silico. Moreover, it enables rationally designing artificial switches, combining essentially arbitrary sensors with a broad choice of read-out systems. Eventually, this approach sets the stage for constructing versatile biosensors.
Collapse
Affiliation(s)
- Sven Findeiß
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
- Faculty of Computer Science, Research Group Bioinformatics and Computational Biology, University of Vienna, Währingerstraße 29, A-1090 Vienna, Austria.
- Faculty of Chemistry, Department of Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria.
| | - Maja Etzel
- Institute for Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Sebastian Will
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
- Faculty of Chemistry, Department of Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria.
- Institute for Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
- Faculty of Chemistry, Department of Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria.
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103 Leipzig, Germany.
- Max Planck Institute for Mathematics in the Sciences, Inselstraße 22, 04103 Leipzig, Germany.
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstrasse 1, 04103 Leipzig, Germany.
- Center for RNA in Technology and Health, University of Copenhagen, Grønnegårdsvej 3, 1870 Frederiksberg , Denmark.
- Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA.
| |
Collapse
|