1
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Kalvaitytė M, Gabrilavičiūtė S, Balciunas D. Rapid generation of single-insertion transgenics by Tol2 transposition in zebrafish. Dev Dyn 2024. [PMID: 38946125 DOI: 10.1002/dvdy.719] [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: 10/12/2023] [Revised: 05/06/2024] [Accepted: 05/14/2024] [Indexed: 07/02/2024] Open
Abstract
BACKGROUND The Tol2 transposable element is the most widely used transgenesis tool in zebrafish. However, its high activity almost always leads to multiple unlinked integrations of the transgenic cassette in F1 fish. Each of these transgenes is susceptible to positional effects from the surrounding regulatory landscape, which can lead to altered expression and, consequently, activity. Scientists therefore must strike a balance between the need to maximize reproducibility by establishing single-insertion transgenic lines and the need to complete experiments within a reasonable timeframe. RESULTS In this article, we introduce a simple competitive dilution strategy for rapid generation of single-insertion transgenics. By using cry:BFP reporter plasmid as a competitor, we achieved a nearly fourfold reduction in the number of the transgene of interest integrations while simultaneously increasing the proportion of single-insertion F1 generation transgenics to over 50%. We also observed variations in transgene of interest expression among independent single-insertion transgenics, highlighting that the commonly used ubiquitous ubb promoter is susceptible to position effects. CONCLUSIONS Wide application of our competitive dilution strategy will save time, reduce animal usage, and improve reproducibility of zebrafish research.
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Affiliation(s)
- Miglė Kalvaitytė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Sofija Gabrilavičiūtė
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Darius Balciunas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
- Department of Biology, Temple University, Philadelphia, Pennsylvania, USA
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2
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Lalonde RL, Wells HH, Kemmler CL, Nieuwenhuize S, Lerma R, Burger A, Mosimann C. pIGLET: Safe harbor landing sites for reproducible and efficient transgenesis in zebrafish. SCIENCE ADVANCES 2024; 10:eadn6603. [PMID: 38838146 PMCID: PMC11152119 DOI: 10.1126/sciadv.adn6603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 05/03/2024] [Indexed: 06/07/2024]
Abstract
Standard zebrafish transgenesis involves random transgene integration with resource-intensive screening. While phiC31 integrase-based attP/attB recombination has streamlined transgenesis in mice and Drosophila, validated attP-based landing sites for universal applications are lacking in zebrafish. Here, we developed phiC31 Integrase Genomic Loci Engineered for Transgenesis (pIGLET) as transgenesis approach, with two attP landing sites pIGLET14a and pIGLET24b from well-validated Tol2 transgenes. Both sites facilitate diverse transgenesis applications including reporters and Cre/loxP transgenes. The pIGLET14a and pIGLET24b landing sites consistently yield 25 to 50% germline transmission, substantially reducing the resources needed for transgenic line generation. Transgenesis into these sites enables reproducible expression patterns in F0 zebrafish embryos for enhancer discovery and testing of gene regulatory variants. Together, our new landing sites streamline targeted, reproducible zebrafish transgenesis as a robust platform for various applications while minimizing the workload for generating transgenic lines.
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Affiliation(s)
| | | | - Cassie L. Kemmler
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Susan Nieuwenhuize
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Raymundo Lerma
- University of Colorado School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
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3
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Gunamalai L, Singh P, Berg B, Shi L, Sanchez E, Smith A, Breton G, Bedford MT, Balciunas D, Kapoor A. Functional characterization of QT interval associated SCN5A enhancer variants identify combined additive effects. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.11.584440. [PMID: 38559211 PMCID: PMC10979898 DOI: 10.1101/2024.03.11.584440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Several empirical and theoretical studies suggest presence of multiple enhancers per gene that collectively regulate gene expression, and that common sequence variation impacting on the activities of these enhancers is a major source of inter-individual variability in gene expression. However, for vast majority of genes, enhancers and the underlying regulatory variation remains unknown. Even for the genes with well-characterized enhancers, the nature of the combined effects from multiple enhancers and their variants, when known, on gene expression regulation remains unexplored. Here, we have evaluated the combined effects from five SCN5A enhancers and their regulatory variants that are known to collectively correlate with SCN5A cardiac expression and underlie QT interval association in the general population. Using small deletions centered at the regulatory variants in episomal reporter assays in a mouse cardiomyocyte cell line we demonstrate that the variants and their flanking sequences play critical role in individual enhancer activities, likely being a transcription factor (TF) binding site. By performing oligonucleotide-based pulldown assays on predicted TFs we identify the TFs likely driving allele-specific enhancer activities. Using all 32 possible allelic synthetic constructs in reporter assays, representing the five biallelic enhancers in tandem in their genomic order, we demonstrate combined additive effects on overall enhancer activities. Using transient enhancer assays in developing zebrafish embryos we demonstrate the four out the five enhancer elements act as enhancers in vivo . Together, these studies extend the previous findings to uncover the TFs driving the enhancer activities of QT interval associated SCN5A regulatory variants, reveal the additive effects from allelic combinations of these regulatory variants, and prove their potential to act as enhancers in vivo .
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4
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Eck E, Moretti B, Schlomann BH, Bragantini J, Lange M, Zhao X, VijayKumar S, Valentin G, Loureiro C, Soroldoni D, Royer LA, Oates AC, Garcia HG. Single-cell transcriptional dynamics in a living vertebrate. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.03.574108. [PMID: 38260569 PMCID: PMC10802376 DOI: 10.1101/2024.01.03.574108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
The ability to quantify transcriptional dynamics in individual cells via live imaging has revolutionized our understanding of gene regulation. However, such measurements are lacking in the context of vertebrate embryos. We addressed this deficit by applying MS2-MCP mRNA labeling to the quantification of transcription in zebrafish, a model vertebrate. We developed a platform of transgenic organisms, light sheet fluorescence microscopy, and optimized image analysis that enables visualization and quantification of MS2 reporters. We used these tools to obtain the first single-cell, real-time measurements of transcriptional dynamics of the segmentation clock. Our measurements challenge the traditional view of smooth clock oscillations and instead suggest a model of discrete transcriptional bursts that are organized in space and time. Together, these results highlight how measuring single-cell transcriptional activity can reveal unexpected features of gene regulation and how this data can fuel the dialogue between theory and experiment.
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Affiliation(s)
- Elizabeth Eck
- Biophysics Graduate Group, University of California at Berkeley, Berkeley, USA
| | - Bruno Moretti
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA, USA
| | - Brandon H. Schlomann
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | | | - Merlin Lange
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA, USA
| | - Xiang Zhao
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA, USA
| | | | | | | | | | - Loïc A. Royer
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA, USA
| | - Andrew C. Oates
- Institute of Bioengineering, EPFL; Lausanne, CH
- Department of Cell and Developmental Biology, UCL; London, UK
- The Francis Crick Institute; London, UK
| | - Hernan G. Garcia
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Department of Physics, University of California, Berkeley, CA, USA
- Institute for Quantitative Biosciences-QB3, University of California, Berkeley, CA, USA
- Chan Zuckerberg Biohub – San Francisco, San Francisco, CA, USA
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5
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Mulligan TS, Mumm JS. Selective Cell Ablation Using an Improved Prodrug-Converting Nitroreductase. Methods Mol Biol 2024; 2707:223-234. [PMID: 37668916 DOI: 10.1007/978-1-0716-3401-1_15] [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: 09/06/2023]
Abstract
Selective cell ablation is an invaluable tool to investigate the function of cell types, the regeneration of cells, and the modeling of diseases associated with cell loss. The nitroreductase (NTR)-mediated cell ablation system is a simple method enabling the elimination of targeted cells through the expression of a nitroreductase enzyme and the application of a prodrug (such as metronidazole). The prodrug is reduced to a cytotoxic product by nitroreductase, thereby leading to DNA damage-induced cell death. In species with elevated regenerative capacity such as zebrafish, removing the prodrug allows endogenous tissue to replace the lost cells. Herein, we describe a method for the use of a markedly improved nitroreductase enzyme for spatially and temporally controlled targeted cell ablation in the zebrafish. Recently, we identified an NTR variant (NTR 2.0) that achieves effective targeted cell ablation at concentrations of metronidazole well below those causing toxic side effects. NTR 2.0 thereby enables the ablation of "resistant" cell types and novel cell ablation paradigms. These advances simplify investigations of cell function, enable interrogations of the effects of chronic inflammation on regenerative processes and facilitate modeling of degenerative diseases associated with chronic cell loss. Techniques for transgenic nitroreductase expression and prodrug application are discussed.
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Affiliation(s)
- Timothy S Mulligan
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Jeff S Mumm
- Department of Ophthalmology, Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA.
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6
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Lalonde RL, Wells HH, Kemmler CL, Nieuwenhuize S, Lerma R, Burger A, Mosimann C. pIGLET: Safe harbor landing sites for reproducible and efficient transgenesis in zebrafish. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.08.570868. [PMID: 38106217 PMCID: PMC10723424 DOI: 10.1101/2023.12.08.570868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Standard methods for transgenesis in zebrafish depend on random transgene integration into the genome followed by resource-intensive screening and validation. Targeted vector integration into validated genomic loci using phiC31 integrase-based attP/attB recombination has transformed mouse and Drosophila transgenesis. However, while the phiC31 system functions in zebrafish, validated loci carrying attP-based landing or safe harbor sites suitable for universal transgenesis applications in zebrafish have not been established. Here, using CRISPR-Cas9, we converted two well-validated single insertion Tol2-based zebrafish transgenes with long-standing genetic stability into two attP landing sites, called phiC31 Integrase Genomic Loci Engineered for Transgenesis (pIGLET). Generating fluorescent reporters, loxP-based Switch lines, CreERT2 drivers, and gene-regulatory variant reporters in the pIGLET14a and pIGLET24b landing site alleles, we document their suitability for transgenesis applications across cell types and developmental stages. For both landing sites, we routinely achieve 25-50% germline transmission of targeted transgene integrations, drastically reducing the number of required animals and necessary resources to generate individual transgenic lines. We document that phiC31 integrase-based transgenesis into pIGLET14a and pIGLET24b reproducibly results in representative reporter expression patterns in injected F0 zebrafish embryos suitable for enhancer discovery and qualitative and quantitative comparison of gene-regulatory element variants. Taken together, our new phiC31 integrase-based transgene landing sites establish reproducible, targeted zebrafish transgenesis for numerous applications while greatly reducing the workload of generating new transgenic zebrafish lines.
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Affiliation(s)
- Robert L. Lalonde
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Harrison H. Wells
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Cassie L. Kemmler
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Susan Nieuwenhuize
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Raymundo Lerma
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Alexa Burger
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
| | - Christian Mosimann
- University of Colorado, School of Medicine, Anschutz Medical Campus, Department of Pediatrics, Section of Developmental Biology, 12801 E 17th Avenue, Aurora, CO 80045, USA
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Papadogiannis V, Hockman D, Mercurio S, Ramsay C, Hintze M, Patthey C, Streit A, Shimeld SM. Evolution of the expression and regulation of the nuclear hormone receptor ERR gene family in the chordate lineage. Dev Biol 2023; 504:12-24. [PMID: 37696353 DOI: 10.1016/j.ydbio.2023.09.003] [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: 04/27/2023] [Revised: 09/01/2023] [Accepted: 09/09/2023] [Indexed: 09/13/2023]
Abstract
The Estrogen Related Receptor (ERR) nuclear hormone receptor genes have a wide diversity of roles in vertebrate development. In embryos, ERR genes are expressed in several tissues, including the central and peripheral nervous systems. Here we seek to establish the evolutionary history of chordate ERR genes, their expression and their regulation. We examine ERR expression in mollusc, amphioxus and sea squirt embryos, finding the single ERR orthologue is expressed in the nervous system in all three, with muscle expression also found in the two chordates. We show that most jawed vertebrates and lampreys have four ERR paralogues, and that vertebrate ERR genes were ancestrally linked to Estrogen Receptor genes. One of the lamprey paralogues shares conserved expression domains with jawed vertebrate ERRγ in the embryonic vestibuloacoustic ganglion, eye, brain and spinal cord. Hypothesising that conserved expression derives from conserved regulation, we identify a suite of pan-vertebrate conserved non-coding sequences in ERR introns. We use transgenesis in lamprey and chicken embryos to show that these sequences are regulatory and drive reporter gene expression in the nervous system. Our data suggest an ancient association between ERR and the nervous system, including expression in cells associated with photosensation and mechanosensation. This includes the origin in the vertebrate common ancestor of a suite of regulatory elements in the 3' introns that drove nervous system expression and have been conserved from this point onwards.
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Affiliation(s)
| | - Dorit Hockman
- Division of Cell Biology, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa; Neuroscience Institute, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Silvia Mercurio
- Department of Environmental Science and Policy, Università Degli Studi di Milano, Via Celoria 2, 20133, Milano, Italy
| | - Claire Ramsay
- Department of Biology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK
| | - Mark Hintze
- Centre for Craniofacial & Regenerative Biology, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Cedric Patthey
- Department of Radiosciences, Umeå University, 901 85, Umeå, Sweden
| | - Andrea Streit
- Centre for Craniofacial & Regenerative Biology, Faculty of Dentistry, Oral and Craniofacial Sciences, King's College London, London, UK
| | - Sebastian M Shimeld
- Department of Biology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK.
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8
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Jimenez Gonzalez A, Baranasic D, Müller F. Zebrafish regulatory genomic resources for disease modelling and regeneration. Dis Model Mech 2023; 16:dmm050280. [PMID: 37529920 PMCID: PMC10417509 DOI: 10.1242/dmm.050280] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023] Open
Abstract
In the past decades, the zebrafish has become a disease model with increasing popularity owing to its advantages that include fast development, easy genetic manipulation, simplicity for imaging, and sharing conserved disease-associated genes and pathways with those of human. In parallel, studies of disease mechanisms are increasingly focusing on non-coding mutations, which require genome annotation maps of regulatory elements, such as enhancers and promoters. In line with this, genomic resources for zebrafish research are expanding, producing a variety of genomic data that help in defining regulatory elements and their conservation between zebrafish and humans. Here, we discuss recent developments in generating functional annotation maps for regulatory elements of the zebrafish genome and how this can be applied to human diseases. We highlight community-driven developments, such as DANIO-CODE, in generating a centralised and standardised catalogue of zebrafish genomics data and functional annotations; consider the advantages and limitations of current annotation maps; and offer considerations for interpreting and integrating existing maps with comparative genomics tools. We also discuss the need for developing standardised genomics protocols and bioinformatic pipelines and provide suggestions for the development of analysis and visualisation tools that will integrate various multiomic bulk sequencing data together with fast-expanding data on single-cell methods, such as single-cell assay for transposase-accessible chromatin with sequencing. Such integration tools are essential to exploit the multiomic chromatin characterisation offered by bulk genomics together with the cell-type resolution offered by emerging single-cell methods. Together, these advances will build an expansive toolkit for interrogating the mechanisms of human disease in zebrafish.
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Affiliation(s)
- Ada Jimenez Gonzalez
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Damir Baranasic
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, London SW7 2AZ, UK
- MRC London Institute of Medical Sciences, London W12 0NN, UK
- Division of Electronics, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia
| | - Ferenc Müller
- Institute of Cancer and Genomic Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
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9
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Hadzhiev Y, Wheatley L, Cooper L, Ansaloni F, Whalley C, Chen Z, Finaurini S, Gustincich S, Sanges R, Burgess S, Beggs A, Müller F. The miR-430 locus with extreme promoter density forms a transcription body during the minor wave of zygotic genome activation. Dev Cell 2023; 58:155-170.e8. [PMID: 36693321 PMCID: PMC9904021 DOI: 10.1016/j.devcel.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 08/10/2022] [Accepted: 12/16/2022] [Indexed: 01/24/2023]
Abstract
In anamniote embryos, the major wave of zygotic genome activation starts during the mid-blastula transition. However, some genes escape global genome repression, are activated substantially earlier, and contribute to the minor wave of genome activation. The mechanisms underlying the minor wave of genome activation are little understood. We explored the genomic organization and cis-regulatory mechanisms of a transcription body, in which the minor wave of genome activation is first detected in zebrafish. We identified the miR-430 cluster as having excessive copy number and the highest density of Pol-II-transcribed promoters in the genome, and this is required for forming the transcription body. However, this transcription body is not essential for, nor does it encompasse, minor wave transcription globally. Instead, distinct minor-wave-specific promoter architecture suggests that promoter-autonomous mechanisms regulate the minor wave of genome activation. The minor-wave-specific features also suggest distinct transcription initiation mechanisms between the minor and major waves of genome activation.
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Affiliation(s)
- Yavor Hadzhiev
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Lucy Wheatley
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Ledean Cooper
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Federico Ansaloni
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK; Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy; Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), 16163 Genoa, Italy
| | - Celina Whalley
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Zhelin Chen
- South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-2152, USA
| | - Sara Finaurini
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy
| | - Stefano Gustincich
- Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), 16163 Genoa, Italy
| | - Remo Sanges
- Area of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy; Central RNA Laboratory, Istituto Italiano di Tecnologia (IIT), 16163 Genoa, Italy
| | - Shawn Burgess
- Translational and Functional Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-2152, USA
| | - Andrew Beggs
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Ferenc Müller
- Institute of Cancer and Genomics Sciences, Birmingham Centre for Genome Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
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10
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Gene expression changes during the evolution of the tetrapod limb. Biol Futur 2022; 73:411-426. [PMID: 36355308 DOI: 10.1007/s42977-022-00136-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 10/26/2022] [Indexed: 11/11/2022]
Abstract
Major changes in the vertebrate anatomy have preceded the conquest of land by the members of this taxon, and continuous changes in limb shape and use have occurred during the later radiation of tetrapods. While the main, conserved mechanisms of limb development have been discerned over the past century using a combination of classical embryological and molecular methods, only recent advances made it possible to identify and study the regulatory changes that have contributed to the evolution of the tetrapod appendage. These advances include the expansion of the model repertoire from traditional genetic model species to non-conventional ones, a proliferation of predictive mathematical models that describe gene interactions, an explosion in genomic data and the development of high-throughput methodologies. These revolutionary innovations make it possible to identify specific mutations that are behind specific transitions in limb evolution. Also, as we continue to apply them to more and more extant species, we can expect to gain a fine-grained view of this evolutionary transition that has been so consequential for our species as well.
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11
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Lalonde RL, Kemmler CL, Riemslagh FW, Aman AJ, Kresoja-Rakic J, Moran HR, Nieuwenhuize S, Parichy DM, Burger A, Mosimann C. Heterogeneity and genomic loci of ubiquitous transgenic Cre reporter lines in zebrafish. Dev Dyn 2022; 251:1754-1773. [PMID: 35582941 PMCID: PMC10069295 DOI: 10.1002/dvdy.499] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 05/10/2022] [Accepted: 05/11/2022] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND The most-common strategy for zebrafish Cre/lox-mediated lineage labeling experiments combines ubiquitously expressed, lox-based Switch reporter transgenes with tissue-specific Cre or 4-OH-Tamoxifen-inducible CreERT2 driver lines. Although numerous Cre driver lines have been produced, only a few broadly expressed Switch reporters exist in zebrafish and their generation by random transgene integration has been challenging due to position-effect sensitivity of the lox-flanked recombination cassettes. Here, we compare commonly used Switch reporter lines for their recombination efficiency and reporter expression pattern during zebrafish development. RESULTS Using different experimental setups, we show that ubi:Switch and hsp70l:Switch outperform current generations of the two additional Switch reporters actb2:BFP-DsRed and actb2:Stop-DsRed. Our comparisons also document preferential Cre-dependent recombination of ubi:Switch and hsp70l:Switch in distinct zebrafish tissues at early developmental stages. To investigate what genomic features may influence Cre accessibility and lox recombination efficiency in highly functional Switch lines, we mapped these transgenes and charted chromatin dynamics at their integration sites. CONCLUSIONS Our data documents the heterogeneity among lox-based Switch transgenes toward informing suitable transgene selection for lineage labeling experiments. Our work further proposes that ubi:Switch and hsp70l:Switch define genomic integration sites suitable for universal transgene or switch reporter knock-in in zebrafish.
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Affiliation(s)
- Robert L Lalonde
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Cassie L Kemmler
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Fréderike W Riemslagh
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Andrew J Aman
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA.,Department of Biology and Department of Cell Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Jelena Kresoja-Rakic
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Hannah R Moran
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Susan Nieuwenhuize
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - David M Parichy
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA.,Department of Biology and Department of Cell Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Alexa Burger
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Christian Mosimann
- Department of Pediatrics, Section of Developmental Biology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, Colorado, USA
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12
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Kalvaitytė M, Balciunas D. Conditional mutagenesis strategies in zebrafish. Trends Genet 2022; 38:856-868. [PMID: 35662532 DOI: 10.1016/j.tig.2022.04.007] [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: 11/16/2021] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 10/18/2022]
Abstract
Gene disruption or knockout is an essential tool for elucidating gene function. Conditional knockout methodology was developed to further advance these studies by enabling gene disruption at a predefined time and/or in discrete cells. While the conditional knockout method is widely used in the mouse, technical limitations have stifled direct adoption of this methodology in other animal models including the zebrafish. Recent advances in genome editing have enabled engineering of distinct classes of conditional mutants in zebrafish. To further accelerate the development and application of conditional mutants, we will review diverse methods of conditional knockout engineering and discuss the advantages of different conditional alleles.
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Affiliation(s)
| | - Darius Balciunas
- Life Sciences Center, Vilnius University, Vilnius, Lithuania; Department of Biology, Temple University, Philadelphia, PA, USA.
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13
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Stepaniak MD, Square TA, Miller CT. Evolved Bmp6 enhancer alleles drive spatial shifts in gene expression during tooth development in sticklebacks. Genetics 2021; 219:6374454. [PMID: 34849839 PMCID: PMC8664583 DOI: 10.1093/genetics/iyab151] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/31/2021] [Indexed: 11/13/2022] Open
Abstract
Mutations in enhancers have been shown to often underlie natural variation but the evolved differences in enhancer activity can be difficult to identify in vivo. Threespine sticklebacks (Gasterosteus aculeatus) are a robust system for studying enhancer evolution due to abundant natural genetic variation, a diversity of evolved phenotypes between ancestral marine and derived freshwater forms, and the tractability of transgenic techniques. Previous work identified a series of polymorphisms within an intronic enhancer of the Bone morphogenetic protein 6 (Bmp6) gene that are associated with evolved tooth gain, a derived increase in freshwater tooth number that arises late in development. Here, we use a bicistronic reporter construct containing a genetic insulator and a pair of reciprocal two-color transgenic reporter lines to compare enhancer activity of marine and freshwater alleles of this enhancer. In older fish, the two alleles drive partially overlapping expression in both mesenchyme and epithelium of developing teeth, but the freshwater enhancer drives a reduced mesenchymal domain and a larger epithelial domain relative to the marine enhancer. In younger fish, these spatial shifts in enhancer activity are less pronounced. Comparing Bmp6 expression by in situ hybridization in developing teeth of marine and freshwater fish reveals similar evolved spatial shifts in gene expression. Together, these data support a model in which the polymorphisms within this enhancer underlie evolved tooth gain by shifting the spatial expression of Bmp6 during tooth development, and provide a general strategy to identify spatial differences in enhancer activity in vivo.
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Affiliation(s)
- Mark D Stepaniak
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Tyler A Square
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Craig T Miller
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
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14
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Bhatia S, Kleinjan DJ, Uttley K, Mann A, Dellepiane N, Bickmore WA. Quantitative spatial and temporal assessment of regulatory element activity in zebrafish. eLife 2021; 10:65601. [PMID: 34796872 PMCID: PMC8604437 DOI: 10.7554/elife.65601] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 10/28/2021] [Indexed: 12/11/2022] Open
Abstract
Mutations or genetic variation in noncoding regions of the genome harbouring cis-regulatory elements (CREs), or enhancers, have been widely implicated in human disease and disease risk. However, our ability to assay the impact of these DNA sequence changes on enhancer activity is currently very limited because of the need to assay these elements in an appropriate biological context. Here, we describe a method for simultaneous quantitative assessment of the spatial and temporal activity of wild-type and disease-associated mutant human CRE alleles using live imaging in zebrafish embryonic development. We generated transgenic lines harbouring a dual-CRE dual-reporter cassette in a pre-defined neutral docking site in the zebrafish genome. The activity of each CRE allele is reported via expression of a specific fluorescent reporter, allowing simultaneous visualisation of where and when in development the wild-type allele is active and how this activity is altered by mutation.
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Affiliation(s)
- Shipra Bhatia
- MRC Human Genetics Unit, Institute of Genetics & Cancer, University of Edinburgh, Edinburgh, United Kingdom
| | - Dirk Jan Kleinjan
- Centre for Mammalian Synthetic Biology at the Institute of Quantitative Biology, Biochemistry, and Biotechnology, SynthSys, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Kirsty Uttley
- MRC Human Genetics Unit, Institute of Genetics & Cancer, University of Edinburgh, Edinburgh, United Kingdom
| | - Anita Mann
- MRC Human Genetics Unit, Institute of Genetics & Cancer, University of Edinburgh, Edinburgh, United Kingdom
| | - Nefeli Dellepiane
- MRC Human Genetics Unit, Institute of Genetics & Cancer, University of Edinburgh, Edinburgh, United Kingdom
| | - Wendy A Bickmore
- MRC Human Genetics Unit, Institute of Genetics & Cancer, University of Edinburgh, Edinburgh, United Kingdom
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15
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Lepanto P, Levin-Ferreyra F, Koziol U, Malacrida L, Badano JL. Insights into in vivo adipocyte differentiation through cell-specific labeling in zebrafish. Biol Open 2021; 10:271875. [PMID: 34409430 PMCID: PMC8443861 DOI: 10.1242/bio.058734] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 08/10/2021] [Indexed: 01/04/2023] Open
Abstract
White adipose tissue hyperplasia has been shown to be crucial for handling excess energy in healthy ways. Though adipogenesis mechanisms have been underscored in vitro, we lack information on how tissue and systemic factors influence the differentiation of new adipocytes. While this could be studied in zebrafish, adipocyte identification currently relies on neutral lipid labeling, thus precluding access to cells in early stages of differentiation. Here we report the generation and analysis of a zebrafish line with the transgene fabp4a(-2.7):EGFPcaax. In vivo confocal microscopy of the pancreatic and abdominal visceral depots of transgenic larvae, revealed the presence of labeled mature adipocytes as well as immature cells in earlier stages of differentiation. Through co-labeling for blood vessels, we observed a close interaction of differentiating adipocytes with endothelial cells through cell protrusions. Finally, we implemented hyperspectral imaging and spectral phasor analysis in Nile Red-labeled transgenic larvae and revealed the lipid metabolic transition towards neutral lipid accumulation of differentiating adipocytes. Altogether our work presents the characterization of a novel adipocyte-specific label in zebrafish and uncovers previously unknown aspects of in vivo adipogenesis. This article has an associated First Person interview with the first author of the paper. Summary: Analysis of the differentiation of adipocytes in vivo through cell-specific labeling in zebrafish, revealed their early interaction with blood vessels as well as early lipid metabolic changes.
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Affiliation(s)
- Paola Lepanto
- Human Molecular Genetics Lab, Institut Pasteur de Montevideo, Montevideo, Mataojo 2020, CP11400, Uruguay
| | - Florencia Levin-Ferreyra
- Human Molecular Genetics Lab, Institut Pasteur de Montevideo, Montevideo, Mataojo 2020, CP11400, Uruguay
| | - Uriel Koziol
- Sección Biología Celular, Facultad de Ciencias, Universidad de la República, Montevideo, Igua 4225, CP11400, Uruguay
| | - Leonel Malacrida
- Advanced Bioimaging Unit, Institut Pasteur de Montevideo and Universidad de la República, Montevideo, Mataojo 2020, CP11400, Uruguay.,Departamento de Fisiopatología, Hospital de Clínicas, Facultad de Medicina, Universidad de la República, Montevideo, Av. Italia s/n, CP11600, Uruguay
| | - José L Badano
- Human Molecular Genetics Lab, Institut Pasteur de Montevideo, Montevideo, Mataojo 2020, CP11400, Uruguay
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16
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Matinyan N, Karkhanis MS, Gonzalez Y, Jain A, Saltzman A, Malovannaya A, Sarrion-Perdigones A, Dierick HA, Venken KJT. Multiplexed drug-based selection and counterselection genetic manipulations in Drosophila. Cell Rep 2021; 36:109700. [PMID: 34525356 PMCID: PMC8480232 DOI: 10.1016/j.celrep.2021.109700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 06/10/2021] [Accepted: 08/20/2021] [Indexed: 01/27/2023] Open
Abstract
The power of Drosophila melanogaster as a model system relies on tractable germline genetic manipulations. Despite Drosophila's expansive genetics toolbox, such manipulations are still accomplished one change at a time and depend predominantly on phenotypic screening. We describe a drug-based genetic platform consisting of four selection and two counterselection markers, eliminating the need to screen for modified progeny. These markers work reliably individually or in combination to produce specific genetic outcomes. We demonstrate three example applications of multiplexed drug-based genetics by generating (1) transgenic animals, expressing both components of binary overexpression systems in a single transgenesis step; (2) dual selectable and counterselectable balancer chromosomes; and (3) selectable, fluorescently tagged P[acman] bacterial artificial chromosome (BAC) strains. We perform immunoprecipitation followed by proteomic analysis on one tagged BAC line, demonstrating our platform's applicability to biological discovery. Lastly, we provide a plasmid library resource to facilitate custom transgene design and technology transfer to other model systems.
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Affiliation(s)
- Nick Matinyan
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA; Integrative Molecular Biomedical Sciences Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mansi S Karkhanis
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yezabel Gonzalez
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Antrix Jain
- Advanced Technology Cores, Mass Spectrometry Proteomics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Alexander Saltzman
- Advanced Technology Cores, Mass Spectrometry Proteomics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Anna Malovannaya
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA; Advanced Technology Cores, Mass Spectrometry Proteomics, Baylor College of Medicine, Houston, TX 77030, USA; Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Alejandro Sarrion-Perdigones
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Herman A Dierick
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Koen J T Venken
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA; Integrative Molecular Biomedical Sciences Graduate Program, Baylor College of Medicine, Houston, TX 77030, USA; Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA; Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, TX 77030, USA; McNair Medical Institute at The Robert and Janice McNair Foundation, Baylor College of Medicine, Houston, TX 77030, USA.
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17
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Figiel DM, Elsayed R, Nelson AC. Investigating the molecular guts of endoderm formation using zebrafish. Brief Funct Genomics 2021:elab013. [PMID: 33754635 DOI: 10.1093/bfgp/elab013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/27/2021] [Accepted: 02/19/2021] [Indexed: 02/07/2023] Open
Abstract
The vertebrate endoderm makes major contributions to the respiratory and gastrointestinal tracts and all associated organs. Zebrafish and humans share a high degree of genetic homology and strikingly similar endodermal organ systems. Combined with a multitude of experimental advantages, zebrafish are an attractive model organism to study endoderm development and disease. Recent functional genomics studies have shed considerable light on the gene regulatory programs governing early zebrafish endoderm development, while advances in biological and technological approaches stand to further revolutionize our ability to investigate endoderm formation, function and disease. Here, we discuss the present understanding of endoderm specification in zebrafish compared to other vertebrates, how current and emerging methods will allow refined and enhanced analysis of endoderm formation, and how integration with human data will allow modeling of the link between non-coding sequence variants and human disease.
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Affiliation(s)
- Daniela M Figiel
- Medical Research Council Doctoral Training Partnership in Interdisciplinary Biomedical Research at Warwick Medical School
| | - Randa Elsayed
- Medical Research Council Doctoral Training Partnership in Interdisciplinary Biomedical Research at Warwick Medical School
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18
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An interhemispheric neural circuit allowing binocular integration in the optic tectum. Nat Commun 2019; 10:5471. [PMID: 31784529 PMCID: PMC6884480 DOI: 10.1038/s41467-019-13484-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 10/30/2019] [Indexed: 11/16/2022] Open
Abstract
Binocular stereopsis requires the convergence of visual information from corresponding points in visual space seen by two different lines of sight. This may be achieved by superposition of retinal input from each eye onto the same downstream neurons via ipsi- and contralaterally projecting optic nerve fibers. Zebrafish larvae can perceive binocular cues during prey hunting but have exclusively contralateral retinotectal projections. Here we report brain activity in the tectal neuropil ipsilateral to the visually stimulated eye, despite the absence of ipsilateral retinotectal projections. This activity colocalizes with arbors of commissural neurons, termed intertectal neurons (ITNs), that connect the tectal hemispheres. ITNs are GABAergic, establish tectal synapses bilaterally and respond to small moving stimuli. ITN-ablation impairs capture swim initiation when prey is positioned in the binocular strike zone. We propose an intertectal circuit that controls execution of the prey-capture motor program following binocular localization of prey, without requiring ipsilateral retinotectal projections. Zebrafish larvae can binocularly detect prey objects in order to strike but lack ipsilateral retinotectal fibers for binocular superposition of visual information. Here the authors describe commissural intertectal neurons and show that they are required for the initiation of capture strikes.
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19
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Mann A, Bhatia S. Zebrafish: A Powerful Model for Understanding the Functional Relevance of Noncoding Region Mutations in Human Genetic Diseases. Biomedicines 2019; 7:E71. [PMID: 31527394 PMCID: PMC6784013 DOI: 10.3390/biomedicines7030071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 08/28/2019] [Accepted: 08/29/2019] [Indexed: 02/06/2023] Open
Abstract
Determining aetiology of genetic disorders caused by damaging mutations in protein-coding genes is well established. However, understanding how mutations in the vast stretches of the noncoding genome contribute to genetic abnormalities remains a huge challenge. Cis-regulatory elements (CREs) or enhancers are an important class of noncoding elements. CREs function as the primary determinants of precise spatial and temporal regulation of their target genes during development by serving as docking sites for tissue-specific transcription factors. Although a large number of potential disease-associated CRE mutations are being identified in patients, lack of robust methods for mechanistically linking these mutations to disease phenotype is currently hampering the understanding of their roles in disease aetiology. Here, we have described the various systems available for testing the CRE potential of stretches of noncoding regions harbouring mutations implicated in human disease. We highlight advances in the field leading to the establishment of zebrafish as a powerful system for robust and cost-effective functional assays of CRE activity, enabling rapid identification of causal variants in regulatory regions and the validation of their role in disruption of appropriate gene expression.
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Affiliation(s)
- Anita Mann
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK.
| | - Shipra Bhatia
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, The University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK.
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20
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Haussmann IU, Ustaoglu P, Brauer U, Hemani Y, Dix TC, Soller M. Plasmid-based gap-repair recombineered transgenes reveal a central role for introns in mutually exclusive alternative splicing in Down Syndrome Cell Adhesion Molecule exon 4. Nucleic Acids Res 2019; 47:1389-1403. [PMID: 30541104 PMCID: PMC6379703 DOI: 10.1093/nar/gky1254] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/22/2018] [Accepted: 12/03/2018] [Indexed: 12/18/2022] Open
Abstract
Alternative splicing is a key feature of human genes, yet studying its regulation is often complicated by large introns. The Down Syndrome Cell Adhesion Molecule (Dscam) gene from Drosophila is one of the most complex genes generating vast molecular diversity by mutually exclusive alternative splicing. To resolve how alternative splicing in Dscam is regulated, we first developed plasmid-based UAS reporter genes for the Dscam variable exon 4 cluster and show that its alternative splicing is recapitulated by GAL4-mediated expression in neurons. We then developed gap-repair recombineering to very efficiently manipulate these large reporter plasmids in Escherichia coli using restriction enzymes or sgRNA/Cas9 DNA scission to capitalize on the many benefits of plasmids in phiC31 integrase-mediated transgenesis. Using these novel tools, we show that inclusion of Dscam exon 4 variables differs little in development and individual flies, and is robustly determined by sequences harbored in variable exons. We further show that introns drive selection of both proximal and distal variable exons. Since exon 4 cluster introns lack conserved sequences that could mediate robust long-range base-pairing to bring exons into proximity for splicing, our data argue for a central role of introns in mutually exclusive alternative splicing of Dscam exon 4 cluster.
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Affiliation(s)
- Irmgard U Haussmann
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.,School of Life Science, CSELS, Coventry University, Coventry CV1 5FB, UK
| | - Pinar Ustaoglu
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Ulrike Brauer
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Yash Hemani
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Thomas C Dix
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Matthias Soller
- School of Biosciences, College of Life and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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21
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Mukherjee K, Liao EC. Generation and characterization of a zebrafish muscle specific inducible Cre line. Transgenic Res 2018; 27:559-569. [PMID: 30353407 PMCID: PMC6364321 DOI: 10.1007/s11248-018-0098-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 10/01/2018] [Indexed: 01/18/2023]
Abstract
Zebrafish transgenic lines provide valuable insights into gene functions, cell lineages and cell behaviors during development. Spatiotemporal control over transgene expression is a critical need in many experimental approaches, with applications in loss- and gain-of-function expression, ectopic expression and lineage tracing experiments. The Cre/loxP recombination system is a powerful tool to provide this control and the demand for validated Cre and loxP zebrafish transgenics is high. One of the major challenges to widespread application of Cre/loxP technology in zebrafish is comparatively small numbers of established tissue-specific Cre or CreERT2 lines. We used Tol2-mediated transgenesis to generate Tg(CrymCherry;-1.9mylz2:CreERT2) which provides an inducible CreERT2 source driven by muscle-specific mylz2 promoter. The transgenic specifically labels the trunk and tail skeletal muscles. We assessed the temporal responsiveness of the transgenic by screening with a validated loxP reporter transgenic ubi:Switch. Further, we evaluated the recombination efficiency in the transgenic with varying concentrations of 4-OHT, for different induction time periods and at different stages of embryogenesis and observed that higher recombination efficiency is achieved when embryos are induced with 10 μM 4-OHT from 10-somites or 24 hpf till 48 or 72 hpf. The transgenic is an addition to currently available zebrafish transgenesis toolbox and a significant tool to advance muscle biology studies in zebrafish.
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Affiliation(s)
- Kusumika Mukherjee
- Center for Regenerative Medicine, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA, 02114, USA
- Division of Plastic and Reconstructive Surgery, Massachusetts General Hospital, Boston, MA, 02114, USA
- Harvard Medical School, Harvard University, Boston, MA, 02115, USA
| | - Eric C Liao
- Center for Regenerative Medicine, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA, 02114, USA.
- Division of Plastic and Reconstructive Surgery, Massachusetts General Hospital, Boston, MA, 02114, USA.
- Harvard Medical School, Harvard University, Boston, MA, 02115, USA.
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22
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Burg L, Palmer N, Kikhi K, Miroshnik ES, Rueckert H, Gaddy E, MacPherson Cunningham C, Mattonet K, Lai SL, Marín-Juez R, Waring RB, Stainier DYR, Balciunas D. Conditional mutagenesis by oligonucleotide-mediated integration of loxP sites in zebrafish. PLoS Genet 2018; 14:e1007754. [PMID: 30427827 PMCID: PMC6261631 DOI: 10.1371/journal.pgen.1007754] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 11/28/2018] [Accepted: 10/10/2018] [Indexed: 02/07/2023] Open
Abstract
Many eukaryotic genes play essential roles in multiple biological processes in several different tissues. Conditional mutants are needed to analyze genes with such pleiotropic functions. In vertebrates, conditional gene inactivation has only been feasible in the mouse, leaving other model systems to rely on surrogate experimental approaches such as overexpression of dominant negative proteins and antisense-based tools. Here, we have developed a simple and straightforward method to integrate loxP sequences at specific sites in the zebrafish genome using the CRISPR/Cas9 technology and oligonucleotide templates for homology directed repair. We engineered conditional (floxed) mutants of tbx20 and fleer, and demonstrate excision of exons flanked by loxP sites using tamoxifen-inducible CreERT2 recombinase. To demonstrate broad applicability of our method, we also integrated loxP sites into two additional genes, aldh1a2 and tcf21. The ease of this approach will further expand the use of zebrafish to study various aspects of vertebrate biology, especially post-embryonic processes such as regeneration. Some genes are expressed and function in a single tissue, and the effect of their loss on that tissue can be readily determined. Frequently, however, genes that are necessary for the development or maintenance of one tissue are also important for other tissues or cell types. Genes of the latter type are difficult to analyze because of the complications resulting from an organism having multiple defects in different tissues. The solution pioneered by mouse geneticists is to inactivate the gene of interest in only one tissue at a time. This elegant approach requires the ability to make specific edits to the genome, a technology that was not readily available to zebrafish researchers until recently. Using the CRISPR/Cas9 genome editing tool, we have developed a simple, reliable, and efficient method to insert DNA sequences into the zebrafish genome that enable conditional gene inactivation. Our methodology will be useful not only for the study of genes that play important roles in multiple tissues, but also for the genetic analysis of biological processes which occur in adult animals.
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Affiliation(s)
- Leonard Burg
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Nicholas Palmer
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Khrievono Kikhi
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Evgeniya S. Miroshnik
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Helen Rueckert
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Eleanor Gaddy
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Carlee MacPherson Cunningham
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Kenny Mattonet
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Shih-Lei Lai
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rubén Marín-Juez
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Richard B. Waring
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
| | - Didier Y. R. Stainier
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Darius Balciunas
- Department of Biology, College of Science and Technology, Temple University, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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23
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Overexpressing ovotransferrin and avian β-defensin-3 improves antimicrobial capacity of chickens and poultry products. Transgenic Res 2018; 28:51-76. [PMID: 30374651 DOI: 10.1007/s11248-018-0101-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/22/2018] [Indexed: 02/08/2023]
Abstract
Zoonotic and foodborne diseases pose a significant burden, decreasing both human and animal health. Modifying chickens to overexpress antimicrobials has the potential to decrease bacterial growth on poultry products and boost chicken innate immunity. Chickens overexpressing either ovotransferrin or avian β-defensin-3 (AvβD3) were generated using Tol-2 transposons. Transgene expression at the RNA and protein level was seen in egg white, breast muscle, and serum. There were significant differences in the immune cell populations in the blood, bursa, and spleen associated with transgene expression including an increased proportion of CD8+ cells in the blood of ovotransferrin and AvβD3 transgenic birds. Expression of the antimicrobials inhibited the in vitro growth of human and chicken bacterial pathogens and spoilage bacteria. For example, transgene expression significantly reduced growth of aerobic and coliform bacteria in breast muscle and decreased the growth of Salmonella enterica in egg white. Overall these results indicate that overexpression of antimicrobials in the chicken can impact the immune system and increase the antimicrobial capacity of poultry products.
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24
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A Collection of Transgenic Medaka Strains for Efficient Site-Directed Transgenesis Mediated by phiC31 Integrase. G3-GENES GENOMES GENETICS 2018; 8:2585-2593. [PMID: 29848622 PMCID: PMC6071608 DOI: 10.1534/g3.118.200130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Genetic analysis is facilitated by the efficient production of transgenic strains expressing a DNA of interest as a single copy at a designated chromosomal location. However, technical progress toward this goal in medaka fish (Oryzias latipes), a vertebrate model organism, has been slow. It is well known that phiC31 integrase enables efficient site-directed transgenesis by catalyzing the recombination of an attP DNA motif in a host genome with an attB motif in a targeting vector. This system was pioneered in medaka using the Sleeping Beauty transposon system, and the attP site was established at three chromosomal locations. However, this number appeared insufficient with regard to genetic linkage between the attP-landing site and a genetically modified locus of interest. Here, to establish a collection of transgenic strains of medaka, we introduced an attP motif into the medaka genome using the Ac/Ds maize transposon system and established 12 independent transgenic strains harboring a single copy of the attP motif in at least 11 of the 24 medaka chromosomes. We designed an attB-targeting vector that was integrated efficiently and precisely into the attP-landing site, and with which the DNA of interest was efficiently transmitted to germline cells. Extraneous sequences in the integrants derived from the bacterial backbone of the attB-targeting vector as well as a transgenic fluorescence marker present in the attP-landing site were removable through flippase-mediated recombination. Further, an advanced targeting vector with a heart-specific recombination marker served as a useful tool for easily screening phiC31 integrase-mediated recombinant G0 embryos, leading to the efficient establishment of transgenic strains. Thus, our resources advance genetic research in medaka.
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25
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Carney TJ, Mosimann C. Switch and Trace: Recombinase Genetics in Zebrafish. Trends Genet 2018; 34:362-378. [PMID: 29429760 DOI: 10.1016/j.tig.2018.01.004] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/04/2018] [Accepted: 01/08/2018] [Indexed: 01/04/2023]
Abstract
Transgenic approaches are instrumental for labeling and manipulating cells and cellular machineries in vivo. Transgenes have traditionally been static entities that remained unaltered following genome integration, limiting their versatility. The development of DNA recombinase-based methods to modify, excise, or rearrange transgene cassettes has introduced versatile control of transgene activity and function. In particular, recombinase-controlled transgenes enable regulation of exogenous gene expression, conditional mutagenesis, and genetic lineage tracing. In zebrafish, transgenesis-based recombinase genetics using Cre/lox, Flp/FRT, and ΦC31 are increasingly applied to study development and homeostasis, and to generate disease models. Intersected with the versatile imaging capacity of the zebrafish model and recent breakthroughs in genome editing, we review and discuss past, current, and potential future approaches and resources for recombinase-based techniques in zebrafish.
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Affiliation(s)
- Tom J Carney
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore; Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), Singapore.
| | - Christian Mosimann
- Institute of Molecular Life Sciences, University of Zürich, Zürich, Switzerland.
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26
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Lalonde RL, Akimenko MA. Effects of fin fold mesenchyme ablation on fin development in zebrafish. PLoS One 2018; 13:e0192500. [PMID: 29420592 PMCID: PMC5805328 DOI: 10.1371/journal.pone.0192500] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 01/24/2018] [Indexed: 11/19/2022] Open
Abstract
The evolution of the tetrapod limb involved an expansion and elaboration of the endoskeletal elements, while the fish fin rays were lost. Loss of fin-specific genes, and regulatory changes in key appendicular patterning genes have been identified as mechanisms of limb evolution, however their contributions to cellular organization and tissue differences between fins and limbs remains poorly understood. During early larval fin development, hoxa13a/hoxd13a-expressing fin fold mesenchyme migrate through the median and pectoral fin along actinotrichia fibrils, non-calcified skeletal elements crucial for supporting the fin fold. Fin fold mesenchyme migration defects have previously been proposed as a mechanism of fin dermal bone loss during tetrapod evolution as it has been shown they contribute directly to the fin ray osteoblast population. Using the nitroreductase/metronidazole system, we genetically ablated a subset of hoxa13a/hoxd13a-expressing fin fold mesenchyme to assess its contributions to fin development. Following the ablation of fin fold mesenchyme in larvae, the actinotrichia are unable to remain rigid and the median and pectoral fin folds collapse, resulting in a reduced fin fold size. The remaining cells following ablation are unable to migrate and show decreased actinodin1 mesenchymal reporter activity. Actinodin proteins are crucial structural component of the actinotrichia. Additionally, we show a decrease in hoxa13a, hoxd13a, fgf10a and altered shha, and ptch2 expression during larval fin development. A continuous treatment of metronidazole leads to fin ray defects at 30dpf. Fewer rays are present compared to stage-matched control larvae, and these rays are shorter and less defined. These results suggest the targeted hoxa13a/hoxd13a-expressing mesenchyme contribute to their own successful migration through their contributions to actinotrichia. Furthermore, due to their fate as fin ray osteoblasts, we propose their initial ablation, and subsequent disorganization produces truncated fin dermal bone elements during late larval stages.
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Affiliation(s)
- Robert L. Lalonde
- Department of Biology, University of Ottawa, 20 Marie-Curie, Ottawa, Ontario, Canada
| | - Marie-Andrée Akimenko
- Department of Biology, University of Ottawa, 20 Marie-Curie, Ottawa, Ontario, Canada
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27
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Abstract
The zebrafish (Danio rerio) possesses a vertebrate-type retina that is extraordinarily conserved in evolution. This well-organized and anatomically easily accessible part of the central nervous system has been widely investigated in zebrafish, promoting general understanding of retinal development, morphology, function and associated diseases. Over the recent years, genome and protein engineering as well as imaging techniques have experienced revolutionary advances and innovations, creating new possibilities and methods to study zebrafish development and function. In this review, we focus on some of these emerging technologies and how they may impact retinal research in the future. We place an emphasis on genetic techniques, such as transgenic approaches and the revolutionizing new possibilities in genome editing.
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Affiliation(s)
- Stephanie Niklaus
- a Institute of Molecular Life Sciences , University of Zurich , Zurich , Switzerland.,b Life Science Zurich Graduate Program - Neuroscience , Zurich , Switzerland
| | - Stephan C F Neuhauss
- a Institute of Molecular Life Sciences , University of Zurich , Zurich , Switzerland
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28
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Chen J, Xia L, Bruchas MR, Solnica-Krezel L. Imaging early embryonic calcium activity with GCaMP6s transgenic zebrafish. Dev Biol 2017; 430:385-396. [PMID: 28322738 PMCID: PMC5835148 DOI: 10.1016/j.ydbio.2017.03.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 01/12/2017] [Accepted: 03/11/2017] [Indexed: 12/02/2022]
Abstract
Intracellular Ca2+ signaling regulates cellular activities during embryogenesis and in adult organisms. We generated stable Tg[βactin2:GCaMP6s]stl351 and Tg[ubi:GCaMP6s]stl352 transgenic lines that combine the ubiquitously-expressed Ca2+ indicator GCaMP6s with the transparent characteristics of zebrafish embryos to achieve superior in vivo Ca2+ imaging. Using the Tg[βactin2:GCaMP6s]stl351 line featuring strong GCaMP6s expression from cleavage through gastrula stages, we detected higher frequency of Ca2+ transients in the superficial blastomeres during the blastula stages preceding the midblastula transition. Additionally, GCaMP6s also revealed that dorsal-biased Ca2+ signaling that follows the midblastula transition persisted longer during gastrulation, compared with earlier studies. We observed that dorsal-biased Ca2+ signaling is diminished in ventralized ichabod/β-catenin2 mutant embryos and ectopically induced in embryos dorsalized by excess β-catenin. During gastrulation, we directly visualized Ca2+ signaling in the dorsal forerunner cells, which form in a Nodal signaling dependent manner and later give rise to the laterality organ. We found that excess Nodal increases the number and the duration of Ca2+ transients specifically in the dorsal forerunner cells. The GCaMP6s transgenic lines described here enable unprecedented visualization of dynamic Ca2+ events from embryogenesis through adulthood, augmenting the zebrafish toolbox.
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Affiliation(s)
- Jiakun Chen
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Li Xia
- Department of Anesthesiology, Division of Basic Research, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St Louis, MO, 63105, USA
| | - Michael R Bruchas
- Department of Anesthesiology, Division of Basic Research, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Biomedical Engineering, Washington University in St. Louis, St Louis, MO, 63105, USA; Department of Neuroscience, Washington University in St. Louis, St. Louis, MO, USA
| | - Lilianna Solnica-Krezel
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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29
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Baxendale S, van Eeden F, Wilkinson R. The Power of Zebrafish in Personalised Medicine. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1007:179-197. [PMID: 28840558 DOI: 10.1007/978-3-319-60733-7_10] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The goal of personalised medicine is to develop tailor-made therapies for patients in whom currently available therapeutics fail. This approach requires correlating individual patient genotype data to specific disease phenotype data and using these stratified data sets to identify bespoke therapeutics. Applications for personalised medicine include common complex diseases which may have multiple targets, as well as rare monogenic disorders, for which the target may be unknown. In both cases, whole genome sequence analysis (WGS) is discovering large numbers of disease associated mutations in new candidate genes and potential modifier genes. Currently, the main limiting factor is the determination of which mutated genes are important for disease progression and therefore represent potential targets for drug discovery. Zebrafish have gained popularity as a model organism for understanding developmental processes, disease mechanisms and more recently for drug discovery and toxicity testing. In this chapter, we will examine the diverse roles that zebrafish can make in the expanding field of personalised medicine, from generating humanised disease models to xenograft screening of different cancer cell lines, through to finding new drugs via in vivo phenotypic screens. We will discuss the tools available for zebrafish research and recent advances in techniques, highlighting the advantages and potential of using zebrafish for high throughput disease modeling and precision drug discovery.
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Affiliation(s)
- Sarah Baxendale
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK.
| | - Freek van Eeden
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK
| | - Robert Wilkinson
- The Bateson Centre, Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, UK.,Department of Infection, Immunity and Cardiovascular Disease, Medical School, Beech Hill Rd, University of Sheffield, Sheffield, S10 2RX, UK
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30
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Genome-Wide Analysis of Transposon and Retroviral Insertions Reveals Preferential Integrations in Regions of DNA Flexibility. G3-GENES GENOMES GENETICS 2016; 6:805-17. [PMID: 26818075 PMCID: PMC4825651 DOI: 10.1534/g3.115.026849] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
DNA transposons and retroviruses are important transgenic tools for genome engineering. An important consideration affecting the choice of transgenic vector is their insertion site preferences. Previous large-scale analyses of Ds transposon integration sites in plants were done on the basis of reporter gene expression or germ-line transmission, making it difficult to discern vertebrate integration preferences. Here, we compare over 1300 Ds transposon integration sites in zebrafish with Tol2 transposon and retroviral integration sites. Genome-wide analysis shows that Ds integration sites in the presence or absence of marker selection are remarkably similar and distributed throughout the genome. No strict motif was found, but a preference for structural features in the target DNA associated with DNA flexibility (Twist, Tilt, Rise, Roll, Shift, and Slide) was observed. Remarkably, this feature is also found in transposon and retroviral integrations in maize and mouse cells. Our findings show that structural features influence the integration of heterologous DNA in genomes, and have implications for targeted genome engineering.
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31
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Felker A, Mosimann C. Contemporary zebrafish transgenesis with Tol2 and application for Cre/lox recombination experiments. Methods Cell Biol 2016; 135:219-44. [PMID: 27443928 DOI: 10.1016/bs.mcb.2016.01.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Spatiotemporal transgene regulation by transgenic DNA recombinases is a central tool for reverse genetics in multicellular organisms, with excellent applications for misexpression and lineage tracing experiments. One of the most widespread technologies for this purpose is Cre recombinase-controlled lox site recombination that is attracting increasing interest in the zebrafish field. Tol2-mediated zebrafish transgenesis provides a stable platform to integrate lox cassette transgenes, while the amenability of the zebrafish embryo to drug treatments makes the model an ideal candidate for tamoxifen-inducible CreERT2 experiments. In addition, advanced transgenesis technologies such as phiC31 or CRISPR-Cas9-based knock-ins are even further promoting zebrafish transgenesis for Cre/lox applications. In this chapter, we will first introduce the basics of Cre/lox methodology, CreERT2 regulation by tamoxifen, as well as the utility of Tol2 and other contemporary transgenesis techniques for Cre/lox experiments. We will then outline in detail practical experimental steps for efficient transgenesis toward the creation of single-insertion transgenes and will introduce protocols for 4-hydroxytamoxifen-mediated CreERT2 induction to perform spatiotemporal lox transgene regulation experiments in zebrafish embryos. Last, we will discuss advanced experimental applications of Cre/lox beyond traditional lineage tracing approaches.
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Affiliation(s)
- A Felker
- University of Zürich, Zürich, Switzerland
| | - C Mosimann
- University of Zürich, Zürich, Switzerland
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32
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Mayrhofer M, Mione M. The Toolbox for Conditional Zebrafish Cancer Models. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 916:21-59. [PMID: 27165348 DOI: 10.1007/978-3-319-30654-4_2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Here we describe the conditional zebrafish cancer toolbox, which allows for fine control of the expression of oncogenes or downregulation of tumor suppressors at the spatial and temporal level. Methods such as the Gal4/UAS or the Cre/lox systems paved the way to the development of elegant tumor models, which are now being used to study cancer cell biology, clonal evolution, identification of cancer stem cells and anti-cancer drug screening. Combination of these tools, as well as novel developments such as the promising genome editing system through CRISPR/Cas9 and clever application of light reactive proteins will enable the development of even more sophisticated zebrafish cancer models. Here, we introduce this growing toolbox of conditional transgenic approaches, discuss its current application in zebrafish cancer models and provide an outlook on future perspectives.
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Affiliation(s)
- Marie Mayrhofer
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Marina Mione
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany.
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33
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Erickson T, Nicolson T. Cell type-specific transcriptomic analysis by thiouracil tagging in zebrafish. Methods Cell Biol 2016; 135:309-28. [DOI: 10.1016/bs.mcb.2016.04.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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34
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Hadzhiev Y, Miguel-Escalada I, Balciunas D, Müller F. Testing of Cis-Regulatory Elements by Targeted Transgene Integration in Zebrafish Using PhiC31 Integrase. Methods Mol Biol 2016; 1451:81-91. [PMID: 27464802 DOI: 10.1007/978-1-4939-3771-4_6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Herein we present several strategies for testing the function of cis-regulatory elements using the PhiC31 integrase system. Firstly, we present two different strategies to analyze the activity of candidate enhancer elements. Targeted integration of candidate enhancers into the same genomic location circumvents the variability-associated random integration and position effects. This method is suitable for testing of candidate enhancers identified through computational or other analyses a priori. Secondly, we present methodology for targeted integration of BACs into the same genomic location(s). By using additional reporters integrated into a BAC, this enables experimental testing whether cis-regulatory elements are functional in the sequence inserted in the BAC.
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Affiliation(s)
- Yavor Hadzhiev
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Irene Miguel-Escalada
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Darius Balciunas
- Department of Biology, Temple University, Philadelphia, PA, 19122, USA
| | - Ferenc Müller
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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35
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Abstract
In this study, we describe the adaptation of the split Gal4 system for zebrafish. The Gal4-UAS system is widely used for expression of genes-of-interest by crossing driver lines expressing the transcription factor Gal4 (under the control of the promoter of interest) with reporter lines where upstream activating sequence (UAS) repeats (recognized by Gal4) drive expression of the genes-of-interest. In the Split Gal4 system, hemi-drivers separately encode the DNA-binding domain (DBD) and the activation domain (AD) of Gal4. When encoded under two different promoters, only those cells in the intersection of the promoters' expression pattern and in which both promoters are active reconstitute a functional Gal4 and activate expression from a UAS-driven transgene. We split the zebrafish-optimized version of Gal4, KalTA4, and generated a hemi-driver encoding the KalTA4 DBD and a hemi-driver encoding KalTA4's AD. We show that split KalTA4 domains can assemble in vivo and transactivate a UAS reporter transgene and that each hemi-driver alone cannot transactivate the reporter. Also, transactivation can happen in several cell types, with similar efficiency to intact KalTA4. Finally, in transient mosaic expression assays, we show that when hemi-drivers are preceded by two distinct promoters, they restrict the expression of an UAS-driven reporter from a broader pattern (sox10) to its constituent smaller neuronal pattern. The Split KalTA4 system should be useful for expression of genes-of-interest in an intersectional manner, allowing for more refined manipulations of cell populations in zebrafish.
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Affiliation(s)
- Rafael Gois Almeida
- 1 Centre for Neuroregeneration, University of Edinburgh , Edinburgh, United Kingdom .,2 MS Society Centre for Translational Research, University of Edinburgh , Edinburgh, United Kingdom .,3 Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh , Edinburgh, United Kingdom
| | - David Anthony Lyons
- 1 Centre for Neuroregeneration, University of Edinburgh , Edinburgh, United Kingdom .,2 MS Society Centre for Translational Research, University of Edinburgh , Edinburgh, United Kingdom .,3 Euan MacDonald Centre for Motor Neurone Disease Research, University of Edinburgh , Edinburgh, United Kingdom
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36
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Venken KJT, Sarrion-Perdigones A, Vandeventer PJ, Abel NS, Christiansen AE, Hoffman KL. Genome engineering: Drosophila melanogaster and beyond. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 5:233-67. [PMID: 26447401 DOI: 10.1002/wdev.214] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 08/03/2015] [Accepted: 08/20/2015] [Indexed: 12/26/2022]
Abstract
A central challenge in investigating biological phenomena is the development of techniques to modify genomic DNA with nucleotide precision that can be transmitted through the germ line. Recent years have brought a boon in these technologies, now collectively known as genome engineering. Defined genomic manipulations at the nucleotide level enable a variety of reverse engineering paradigms, providing new opportunities to interrogate diverse biological functions. These genetic modifications include controlled removal, insertion, and substitution of genetic fragments, both small and large. Small fragments up to a few kilobases (e.g., single nucleotide mutations, small deletions, or gene tagging at single or multiple gene loci) to large fragments up to megabase resolution can be manipulated at single loci to create deletions, duplications, inversions, or translocations of substantial sections of whole chromosome arms. A specialized substitution of chromosomal portions that presumably are functionally orthologous between different organisms through syntenic replacement, can provide proof of evolutionary conservation between regulatory sequences. Large transgenes containing endogenous or synthetic DNA can be integrated at defined genomic locations, permitting an alternative proof of evolutionary conservation, and sophisticated transgenes can be used to interrogate biological phenomena. Precision engineering can additionally be used to manipulate the genomes of organelles (e.g., mitochondria). Novel genome engineering paradigms are often accelerated in existing, easily genetically tractable model organisms, primarily because these paradigms can be integrated in a rigorous, existing technology foundation. The Drosophila melanogaster fly model is ideal for these types of studies. Due to its small genome size, having just four chromosomes, the vast amount of cutting-edge genetic technologies, and its short life-cycle and inexpensive maintenance requirements, the fly is exceptionally amenable to complex genetic analysis using advanced genome engineering. Thus, highly sophisticated methods developed in the fly model can be used in nearly any sequenced organism. Here, we summarize different ways to perform precise inheritable genome engineering using integrases, recombinases, and DNA nucleases in the D. melanogaster. For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Koen J T Venken
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA.,Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA.,Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX, USA.,Program in Integrative Molecular and Biomedical Sciences, Baylor College of Medicine, Houston, TX, USA
| | | | - Paul J Vandeventer
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA
| | - Nicholas S Abel
- Department of Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Audrey E Christiansen
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA
| | - Kristi L Hoffman
- Department of Biochemistry and Molecular Biology, Verna and Marrs McLean, Houston, TX, USA
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37
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The integration characteristics of the exogenous growth hormone gene in a transgenic common carp (Cyprinus carpio L.) with fast-growth performance. Sci Bull (Beijing) 2015. [DOI: 10.1007/s11434-015-0893-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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38
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Bhatia S, Gordon CT, Foster RG, Melin L, Abadie V, Baujat G, Vazquez MP, Amiel J, Lyonnet S, van Heyningen V, Kleinjan DA. Functional assessment of disease-associated regulatory variants in vivo using a versatile dual colour transgenesis strategy in zebrafish. PLoS Genet 2015; 11:e1005193. [PMID: 26030420 PMCID: PMC4452300 DOI: 10.1371/journal.pgen.1005193] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 04/02/2015] [Indexed: 11/26/2022] Open
Abstract
Disruption of gene regulation by sequence variation in non-coding regions of the genome is now recognised as a significant cause of human disease and disease susceptibility. Sequence variants in cis-regulatory elements (CREs), the primary determinants of spatio-temporal gene regulation, can alter transcription factor binding sites. While technological advances have led to easy identification of disease-associated CRE variants, robust methods for discerning functional CRE variants from background variation are lacking. Here we describe an efficient dual-colour reporter transgenesis approach in zebrafish, simultaneously allowing detailed in vivo comparison of spatio-temporal differences in regulatory activity between putative CRE variants and assessment of altered transcription factor binding potential of the variant. We validate the method on known disease-associated elements regulating SHH, PAX6 and IRF6 and subsequently characterise novel, ultra-long-range SOX9 enhancers implicated in the craniofacial abnormality Pierre Robin Sequence. The method provides a highly cost-effective, fast and robust approach for simultaneously unravelling in a single assay whether, where and when in embryonic development a disease-associated CRE-variant is affecting its regulatory function. Cis-regulatory elements (CREs) play a vital role in gene regulation by providing spatial and temporal specificity to the expression of their target genes. Understanding how these regions of the genome work is of vital importance for human health as it has been demonstrated that genetic changes in these regions can result in incorrect gene expression, leading to a variety of human diseases. Functional characterization of putative CREs and the effects of mutations on their activity is currently a major bottleneck in many studies towards understanding the causes and mechanisms of disease and disease susceptibility. We describe a robust in-vivo approach using dual-colour reporter transgenesis in zebrafish for unambiguous assessment of the effects of disease-associated CRE mutations on CRE activity during the entire time-course of embryonic development. The highly efficient, cost-effective and modular design of the assay allows rapid analysis of several CRE-variants in parallel. We illustrate the robustness of our approach using examples of CRE-variants associated with a broad spectrum of genetic diseases including brain, limb, eye and jaw disorders. In a single assay the method can address where and when in development the CRE variant affects its activity, what potential target genes are misregulated by the change and what upstream trans-acting factors are likely to mediate this effect.
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Affiliation(s)
- Shipra Bhatia
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail: (SB); (VvH); (DAK)
| | - Christopher T. Gordon
- INSERM U781, Hôpital Necker-Enfants Malades and Université Paris Descartes-Sorbonne Paris Cité, Institute Imagine, Paris, France
| | - Robert G. Foster
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Lucie Melin
- INSERM U781, Hôpital Necker-Enfants Malades and Université Paris Descartes-Sorbonne Paris Cité, Institute Imagine, Paris, France
| | - Véronique Abadie
- Service de Pédiatrie Générale, Université Paris Descartes, Hôpital Necker-Enfants Malades, Paris, France
| | - Geneviève Baujat
- Departement de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris France
| | - Marie-Paule Vazquez
- Service de Chirurgie Maxillo-Faciale et Plastique, CRMR des Malformations de la Face et de la Cavité Buccale, Hôpital Necker-Enfants Malades, Paris, France
| | - Jeanne Amiel
- INSERM U781, Hôpital Necker-Enfants Malades and Université Paris Descartes-Sorbonne Paris Cité, Institute Imagine, Paris, France
- Departement de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris France
| | - Stanislas Lyonnet
- INSERM U781, Hôpital Necker-Enfants Malades and Université Paris Descartes-Sorbonne Paris Cité, Institute Imagine, Paris, France
- Departement de Génétique, Hôpital Necker-Enfants Malades, AP-HP, Paris France
| | - Veronica van Heyningen
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail: (SB); (VvH); (DAK)
| | - Dirk A. Kleinjan
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail: (SB); (VvH); (DAK)
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39
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Pitzschke A. Modes of MAPK substrate recognition and control. TRENDS IN PLANT SCIENCE 2015; 20:49-55. [PMID: 25301445 DOI: 10.1016/j.tplants.2014.09.006] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/10/2014] [Accepted: 09/16/2014] [Indexed: 05/04/2023]
Abstract
Mitogen-activated protein kinase (MAPK) cascades are universal, evolutionary conserved signalling modules, which translate environmental information into appropriate responses via phosphorylation of their substrate proteins. In Arabidopsis, the MAPK MPK3 regulates numerous cellular processes, including the adaptation to abiotic and biotic stresses. The molecular steps immediately downstream of MPK3 induction have, therefore, received abundant attention, and a respectable number of MPK3 targets are known by now. These proteins illustrate the substrate promiscuity of MPK3. They also are evidence for how manifold phosphorylation-regulated functions can be. This review presents the current knowledge about the function and regulation of MPK3-targeted proteins, takes a close look at their primary protein sequences, and proposes a model of how MPK3 recognises, binds, and phosphorylates its targets.
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Affiliation(s)
- Andrea Pitzschke
- Department of Applied Genetics and Cell Biology (DAGZ), University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, Vienna A-1190, Austria.
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40
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Abstract
The use of transgenics in fish is a relatively recent development for advancing understanding of genetic mechanisms and developmental processes, improving aquaculture, and for pharmaceutical discovery. Transgenic fish have also been applied in ecotoxicology where they have the potential to provide more advanced and integrated systems for assessing health impacts of chemicals. The zebrafish (Daniorerio) is the most popular fish for transgenic models, for reasons including their high fecundity, transparency of their embryos, rapid organogenesis and availability of extensive genetic resources. The most commonly used technique for producing transgenic zebrafish is via microinjection of transgenes into fertilized eggs. Transposon and meganuclease have become the most reliable methods for insertion of the genetic construct in the production of stable transgenic fish lines. The GAL4-UAS system, where GAL4 is placed under the control of a desired promoter and UAS is fused with a fluorescent marker, has greatly enhanced model development for studies in ecotoxicology. Transgenic fish have been developed to study for the effects of heavy metal toxicity (via heat-shock protein genes), oxidative stress (via an electrophile-responsive element), for various organic chemicals acting through the aryl hydrocarbon receptor, thyroid and glucocorticoid response pathways, and estrogenicity. These models vary in their sensitivity with only very few able to detect responses for environmentally relevant exposures. Nevertheless, the potential of these systems for analyses of chemical effects in real time and across multiple targets in intact organisms is considerable. Here we illustrate the techniques used for generating transgenic zebrafish and assess progress in the development and application of transgenic fish (principally zebrafish) for studies in environmental toxicology. We further provide a viewpoint on future development opportunities.
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Affiliation(s)
- Okhyun Lee
- Biosciences, College of Life & Environmental Sciences, University of Exeter , Exeter, Devon , UK
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41
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Braasch I, Peterson SM, Desvignes T, McCluskey BM, Batzel P, Postlethwait JH. A new model army: Emerging fish models to study the genomics of vertebrate Evo-Devo. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2014; 324:316-41. [PMID: 25111899 DOI: 10.1002/jez.b.22589] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Revised: 06/19/2014] [Accepted: 06/25/2014] [Indexed: 01/08/2023]
Abstract
Many fields of biology--including vertebrate Evo-Devo research--are facing an explosion of genomic and transcriptomic sequence information and a multitude of fish species are now swimming in this "genomic tsunami." Here, we first give an overview of recent developments in sequencing fish genomes and transcriptomes that identify properties of fish genomes requiring particular attention and propose strategies to overcome common challenges in fish genomics. We suggest that the generation of chromosome-level genome assemblies--for which we introduce the term "chromonome"--should be a key component of genomic investigations in fish because they enable large-scale conserved synteny analyses that inform orthology detection, a process critical for connectivity of genomes. Orthology calls in vertebrates, especially in teleost fish, are complicated by divergent evolution of gene repertoires and functions following two rounds of genome duplication in the ancestor of vertebrates and a third round at the base of teleost fish. Second, using examples of spotted gar, basal teleosts, zebrafish-related cyprinids, cavefish, livebearers, icefish, and lobefin fish, we illustrate how next generation sequencing technologies liberate emerging fish systems from genomic ignorance and transform them into a new model army to answer longstanding questions on the genomic and developmental basis of their biodiversity. Finally, we discuss recent progress in the genetic toolbox for the major fish models for functional analysis, zebrafish, and medaka, that can be transferred to many other fish species to study in vivo the functional effect of evolutionary genomic change as Evo-Devo research enters the postgenomic era.
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Affiliation(s)
- Ingo Braasch
- Institute of Neuroscience, University of Oregon, Eugene, Oregon
| | | | | | | | - Peter Batzel
- Institute of Neuroscience, University of Oregon, Eugene, Oregon
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Park JT, Johnson N, Liu S, Levesque M, Wang YJ, Ho H, Huso D, Maitra A, Parsons MJ, Prescott JD, Leach SD. Differential in vivo tumorigenicity of diverse KRAS mutations in vertebrate pancreas: A comprehensive survey. Oncogene 2014; 34:2801-6. [PMID: 25065594 PMCID: PMC4836617 DOI: 10.1038/onc.2014.223] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 06/09/2014] [Accepted: 06/15/2014] [Indexed: 12/30/2022]
Abstract
Somatic activation of the KRAS proto-oncogene is evident in almost all pancreatic cancers, and appears to represent an initiating event. These mutations occur primarily at codon 12 and less frequently at codons 13 and 61. While some studies have suggested that different KRAS mutations may have variable oncogenic properties, to date there has been no comprehensive functional comparison of multiple KRAS mutations in an in vivo vertebrate tumorigenesis system. We generated a Gal4/UAS-based zebrafish model of pancreatic tumorigenesis in which the pancreatic expression of UAS-regulated oncogenes is driven by a ptf1a:Gal4-VP16 driver line. This system allowed us to rapidly compare the ability of 12 different KRAS mutations (G12A, G12C, G12D, G12F, G12R, G12S, G12V, G13C, G13D, Q61L, Q61R, and A146T) to drive pancreatic tumorigenesis in vivo. Among fish injected with one of five KRAS mutations reported in other tumor types but not in human pancreatic cancer, 2/79 (0.25%) developed pancreatic tumors, with both tumors arising in fish injected with A146T. In contrast, among fish injected with one of seven KRAS mutations known to occur in human pancreatic cancer, 22/106 (20.8%) developed pancreatic cancer. All eight tumorigenic KRAS mutations were associated with downstream MAPK/ERK pathway activation in preneoplastic pancreatic epithelium, while non-tumorigenic mutations were not. These results suggest that the spectrum of KRAS mutations observed in human pancreatic cancer reflects selection based upon variable tumorigenic capacities, including the ability to activate MAPK/ERK signaling.
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Affiliation(s)
- J T Park
- Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - N Johnson
- Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - S Liu
- Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - M Levesque
- Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - Y J Wang
- Graduate Program in Human Genetics, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - H Ho
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - D Huso
- Department of Molecular & Comparative Pathobiology, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - A Maitra
- Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - M J Parsons
- 1] Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA [2] Graduate Program in Human Genetics, Johns Hopkins Medical Institutions, Baltimore, MD, USA [3] Institute of Genetic Medicine, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - J D Prescott
- Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - S D Leach
- 1] Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, MD, USA [2] Graduate Program in Human Genetics, Johns Hopkins Medical Institutions, Baltimore, MD, USA [3] Institute of Genetic Medicine, Johns Hopkins Medical Institutions, Baltimore, MD, USA
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Patten SA, Armstrong GAB, Lissouba A, Kabashi E, Parker JA, Drapeau P. Fishing for causes and cures of motor neuron disorders. Dis Model Mech 2014; 7:799-809. [PMID: 24973750 PMCID: PMC4073270 DOI: 10.1242/dmm.015719] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Motor neuron disorders (MNDs) are a clinically heterogeneous group of neurological diseases characterized by progressive degeneration of motor neurons, and share some common pathological pathways. Despite remarkable advances in our understanding of these diseases, no curative treatment for MNDs exists. To better understand the pathogenesis of MNDs and to help develop new treatments, the establishment of animal models that can be studied efficiently and thoroughly is paramount. The zebrafish (Danio rerio) is increasingly becoming a valuable model for studying human diseases and in screening for potential therapeutics. In this Review, we highlight recent progress in using zebrafish to study the pathology of the most common MNDs: spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS) and hereditary spastic paraplegia (HSP). These studies indicate the power of zebrafish as a model to study the consequences of disease-related genes, because zebrafish homologues of human genes have conserved functions with respect to the aetiology of MNDs. Zebrafish also complement other animal models for the study of pathological mechanisms of MNDs and are particularly advantageous for the screening of compounds with therapeutic potential. We present an overview of their potential usefulness in MND drug discovery, which is just beginning and holds much promise for future therapeutic development.
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Affiliation(s)
- Shunmoogum A Patten
- Department of Neuroscience, FRQS Groupe de Recherche sur le Système Nerveux Central and CRCHUM, University of Montréal, Montréal, QC H3A 2B4, Canada
| | - Gary A B Armstrong
- Department of Neuroscience, FRQS Groupe de Recherche sur le Système Nerveux Central and CRCHUM, University of Montréal, Montréal, QC H3A 2B4, Canada
| | - Alexandra Lissouba
- Department of Neuroscience, FRQS Groupe de Recherche sur le Système Nerveux Central and CRCHUM, University of Montréal, Montréal, QC H3A 2B4, Canada
| | - Edor Kabashi
- Institut du Cerveau et de la Moelle Épinière, Centre de Recherche, CHU Pitié-Salpétrière, 75013 Paris, France
| | - J Alex Parker
- Department of Neuroscience, FRQS Groupe de Recherche sur le Système Nerveux Central and CRCHUM, University of Montréal, Montréal, QC H3A 2B4, Canada
| | - Pierre Drapeau
- Department of Neuroscience, FRQS Groupe de Recherche sur le Système Nerveux Central and CRCHUM, University of Montréal, Montréal, QC H3A 2B4, Canada.
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