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Lauri A, Fasano G, Venditti M, Dallapiccola B, Tartaglia M. In vivo Functional Genomics for Undiagnosed Patients: The Impact of Small GTPases Signaling Dysregulation at Pan-Embryo Developmental Scale. Front Cell Dev Biol 2021; 9:642235. [PMID: 34124035 PMCID: PMC8194860 DOI: 10.3389/fcell.2021.642235] [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: 12/15/2020] [Accepted: 03/12/2021] [Indexed: 12/24/2022] Open
Abstract
While individually rare, disorders affecting development collectively represent a substantial clinical, psychological, and socioeconomic burden to patients, families, and society. Insights into the molecular mechanisms underlying these disorders are required to speed up diagnosis, improve counseling, and optimize management toward targeted therapies. Genome sequencing is now unveiling previously unexplored genetic variations in undiagnosed patients, which require functional validation and mechanistic understanding, particularly when dealing with novel nosologic entities. Functional perturbations of key regulators acting on signals' intersections of evolutionarily conserved pathways in these pathological conditions hinder the fine balance between various developmental inputs governing morphogenesis and homeostasis. However, the distinct mechanisms by which these hubs orchestrate pathways to ensure the developmental coordinates are poorly understood. Integrative functional genomics implementing quantitative in vivo models of embryogenesis with subcellular precision in whole organisms contribute to answering these questions. Here, we review the current knowledge on genes and mechanisms critically involved in developmental syndromes and pediatric cancers, revealed by genomic sequencing and in vivo models such as insects, worms and fish. We focus on the monomeric GTPases of the RAS superfamily and their influence on crucial developmental signals and processes. We next discuss the effectiveness of exponentially growing functional assays employing tractable models to identify regulatory crossroads. Unprecedented sophistications are now possible in zebrafish, i.e., genome editing with single-nucleotide precision, nanoimaging, highly resolved recording of multiple small molecules activity, and simultaneous monitoring of brain circuits and complex behavioral response. These assets permit accurate real-time reporting of dynamic small GTPases-controlled processes in entire organisms, owning the potential to tackle rare disease mechanisms.
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Affiliation(s)
- Antonella Lauri
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | | | | | | | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
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2
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Fabian L, Dowling JJ. Zebrafish Models of LAMA2-Related Congenital Muscular Dystrophy (MDC1A). Front Mol Neurosci 2020; 13:122. [PMID: 32742259 PMCID: PMC7364686 DOI: 10.3389/fnmol.2020.00122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/11/2020] [Indexed: 01/28/2023] Open
Abstract
LAMA2-related congenital muscular dystrophy (CMD; LAMA2-MD), also referred to as merosin deficient CMD (MDC1A), is a severe neonatal onset muscle disease caused by recessive mutations in the LAMA2 gene. LAMA2 encodes laminin α2, a subunit of the extracellular matrix (ECM) oligomer laminin 211. There are currently no treatments for MDC1A, and there is an incomplete understanding of disease pathogenesis. Zebrafish, due to their high degree of genetic conservation with humans, large clutch sizes, rapid development, and optical clarity, have emerged as an excellent model system for studying rare Mendelian diseases. They are particularly suitable as a model for muscular dystrophy because they contain at least one orthologue to all major human MD genes, have muscle that is similar to human muscle in structure and function, and manifest obvious and easily measured MD related phenotypes. In this review article, we present the existing zebrafish models of MDC1A, and discuss their contribution to the understanding of MDC1A pathomechanisms and therapy development.
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Affiliation(s)
- Lacramioara Fabian
- Program for Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada
| | - James J Dowling
- Program for Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada.,Division of Neurology, Hospital for Sick Children, Toronto, ON, Canada.,Departments of Pediatrics and Molecular Genetics, University of Toronto, Toronto, ON, Canada
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3
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Zhang X, Song J, Klymov A, Zhang Y, de Boer L, Jansen JA, van den Beucken JJ, Yang F, Zaat SA, Leeuwenburgh SC. Monitoring local delivery of vancomycin from gelatin nanospheres in zebrafish larvae. Int J Nanomedicine 2018; 13:5377-5394. [PMID: 30254441 PMCID: PMC6143646 DOI: 10.2147/ijn.s168959] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background Infections such as biomaterial-associated infection and osteomyelitis are often associated with intracellular survival of bacteria (eg, Staphylococcus aureus). Treatment of these infections remains a major challenge due to the low intracellular efficacy of many antibiotics. Therefore, local delivery systems are urgently required to improve the therapeutic efficacy of antibiotics by enabling their intracellular delivery. Purpose To assess the potential of gelatin nanospheres as carriers for local delivery of vancomycin into macrophages of zebrafish larvae in vivo and into THP-1-derived macrophages in vitro using fluorescence microscopy. Materials and methods Fluorescently labeled gelatin nanospheres were prepared and injected into transgenic zebrafish larvae with fluorescent macrophages. Both the biodistribution of gelatin nanospheres in zebrafish larvae and the co-localization of vancomycin-loaded gelatin nanospheres with zebrafish macrophages in vivo and uptake by THP-1-derived macrophages in vitro were studied. In addition, the effect of treatment with vancomycin-loaded gelatin nanospheres on survival of S. aureus-infected zebrafish larvae was investigated. Results Internalization of vancomycin-loaded gelatin nanospheres by macrophages was observed qualitatively both in vivo and in vitro. Systemically delivered vancomycin, on the other hand, was hardly internalized by macrophages without the use of gelatin nanospheres. Treatment with a single dose of vancomycin-loaded gelatin nanospheres delayed the mortality of S. aureus-infected zebrafish larvae, indicating the improved therapeutic efficacy of vancomycin against (intracellular) S. aureus infection in vivo. Conclusion The present study demonstrates that gelatin nanospheres can be used to facilitate local and intracellular delivery of vancomycin.
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Affiliation(s)
- Xiaolin Zhang
- Department of Medical Microbiology, Amsterdam Infection and Immunity Institute, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Department of Biomaterials Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, the Netherlands
| | - Jiankang Song
- Department of Biomaterials, Radboud University Medical Centre, Nijmegen, the Netherlands,
| | - Alexey Klymov
- Department of Biomaterials, Radboud University Medical Centre, Nijmegen, the Netherlands,
| | - Yang Zhang
- Department of Biomaterials, Radboud University Medical Centre, Nijmegen, the Netherlands,
| | - Leonie de Boer
- Department of Medical Microbiology, Amsterdam Infection and Immunity Institute, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - John A Jansen
- Department of Biomaterials, Radboud University Medical Centre, Nijmegen, the Netherlands,
| | | | - Fang Yang
- Department of Biomaterials, Radboud University Medical Centre, Nijmegen, the Netherlands,
| | - Sebastian Aj Zaat
- Department of Medical Microbiology, Amsterdam Infection and Immunity Institute, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Sander Cg Leeuwenburgh
- Department of Biomaterials, Radboud University Medical Centre, Nijmegen, the Netherlands,
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Chow RWY, Lamperti P, Steed E, Boselli F, Vermot J. Following Endocardial Tissue Movements via Cell Photoconversion in the Zebrafish Embryo. J Vis Exp 2018. [PMID: 29553538 DOI: 10.3791/57290] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
During embryogenesis, cells undergo dynamic changes in cell behavior, and deciphering the cellular logic behind these changes is a fundamental goal in the field of developmental biology. The discovery and development of photoconvertible proteins have greatly aided our understanding of these dynamic changes by providing a method to optically highlight cells and tissues. However, while photoconversion, time-lapse microscopy, and subsequent image analysis have proven to be very successful in uncovering cellular dynamics in organs such as the brain or the eye, this approach is generally not used in the developing heart due to challenges posed by the rapid movement of the heart during the cardiac cycle. This protocol consists of two parts. The first part describes a method for photoconverting and subsequently tracking endocardial cells (EdCs) during zebrafish atrioventricular canal (AVC) and atrioventricular heart valve development. The method involves temporally stopping the heart with a drug in order for accurate photoconversion to take place. Hearts are allowed to resume beating upon removal of the drug and embryonic development continues normally until the heart is stopped again for high-resolution imaging of photoconverted EdCs at a later developmental time point. The second part of the protocol describes an image analysis method to quantify the length of a photoconverted or non-photoconverted region in the AVC in young embryos by mapping the fluorescent signal from the three-dimensional structure onto a two-dimensional map. Together, the two parts of the protocol allows one to examine the origin and behavior of cells that make up the zebrafish AVC and atrioventricular heart valve, and can potentially be applied for studying mutants, morphants, or embryos that have been treated with reagents that disrupt AVC and/or valve development.
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Affiliation(s)
- Renee Wei-Yan Chow
- Institut de Génétique et de Biologie Moléculaire et Cellulaire; UMR7104, Centre National de la Recherche Scientifique; U964, Institut National de la Santé et de la Recherche Médicale; Université de Strasbourg
| | - Paola Lamperti
- Institut de Génétique et de Biologie Moléculaire et Cellulaire; UMR7104, Centre National de la Recherche Scientifique; U964, Institut National de la Santé et de la Recherche Médicale; Université de Strasbourg
| | - Emily Steed
- Institut de Génétique et de Biologie Moléculaire et Cellulaire; UMR7104, Centre National de la Recherche Scientifique; U964, Institut National de la Santé et de la Recherche Médicale; Université de Strasbourg
| | - Francesco Boselli
- Institut de Génétique et de Biologie Moléculaire et Cellulaire; UMR7104, Centre National de la Recherche Scientifique; U964, Institut National de la Santé et de la Recherche Médicale; Université de Strasbourg
| | - Julien Vermot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire; UMR7104, Centre National de la Recherche Scientifique; U964, Institut National de la Santé et de la Recherche Médicale; Université de Strasbourg;
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5
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Wu S, Chou H, Yuh C, Mekuria SL, Kao Y, Tsai H. Radiation-Sensitive Dendrimer-Based Drug Delivery System. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1700339. [PMID: 29610720 PMCID: PMC5827102 DOI: 10.1002/advs.201700339] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/10/2017] [Indexed: 05/13/2023]
Abstract
Combination of chemotherapy and radiotherapy is used to enhance local drug delivery while reducing off-target tissue effects. Anticancer drug doxorubicin (DOX) is loaded into l-cysteine modified G4.5 dendrimer (GC/DOX) and released at different pH values in the presence and absence of γ-radiation. Presence of γ-radiation significantly improves DOX release from the GC/DOX under acidic pH conditions, suggesting that GC dendrimer is a radiation-sensitive drug delivery system. GC/DOX is further evaluated by determining cytotoxicity in uterine cervical carcinoma HeLa cells. GC/DOX shows high affinity for cancer cells and effective drug release following an external stimulus (radiation exposure), whereas an in vivo zebrafish study confirms that l-cysteine acts as a radiosensitizer. GC/DOX treatment combined with radiotherapy synergistically and successfully inhibits cancer cell growth.
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Affiliation(s)
- Szu‐Yuan Wu
- Department of Radiation OncologyWan Fang HospitalTaipei Medical University116TaipeiTaiwan
- Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical University110TaipeiTaiwan
| | - Hsiao‐Ying Chou
- Graduate Institute of Applied Science and TechnologyNational Taiwan University of Science and Technology106TaipeiTaiwan
| | - Chiou‐Hwa Yuh
- Institute of Molecular and Genomic MedicineNational Health Research Institutes350ZhunanMiaoliTaiwan
- Institute of Bioinformatics and Structural BiologyNational Tsing Hua University300HsinchuTaiwan
- Department of Biological Science and TechnologyNational Chiao Tung University300HsinchuTaiwan
| | - Shewaye Lakew Mekuria
- Graduate Institute of Applied Science and TechnologyNational Taiwan University of Science and Technology106TaipeiTaiwan
| | - Yu‐Chih Kao
- Graduate Institute of Applied Science and TechnologyNational Taiwan University of Science and Technology106TaipeiTaiwan
| | - Hsieh‐Chih Tsai
- Graduate Institute of Applied Science and TechnologyNational Taiwan University of Science and Technology106TaipeiTaiwan
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Ocaña OH, Coskun H, Minguillón C, Murawala P, Tanaka EM, Galcerán J, Muñoz-Chápuli R, Nieto MA. A right-handed signalling pathway drives heart looping in vertebrates. Nature 2018; 549:86-90. [PMID: 28880281 PMCID: PMC5590727 DOI: 10.1038/nature23454] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 06/29/2017] [Indexed: 12/19/2022]
Abstract
The majority of animals show external bilateral symmetry, precluding the observation of multiple internal left-right (L/R) asymmetries that are fundamental for organ packaging and function1,2. In vertebrates, left identity is mediated by the left-specific Nodal-Pitx2 axis that is repressed on the right-hand side by the epithelial-mesenchymal transition (EMT) inducer Snail13,4. Despite some existing evidence3,5, it remains unclear whether an equivalent instructive pathway provides right-hand specific information to the embryo. Here we show that in zebrafish, BMP mediates the L/R asymmetric activation of another EMT inducer, Prrx1a, in the lateral plate mesoderm (LPM) with higher levels on the right. Prrx1a drives L/R differential cell movements towards the midline leading to a leftward displacement of the cardiac posterior pole through an actomyosin-dependent mechanism. Downregulation of Prrx1a prevents heart looping and leads to mesocardia. Two parallel and mutually repressed pathways, respectively driven by Nodal and BMP on the left and right LPM, converge on the asymmetric activation of Pitx2 and Prrx1, two transcription factors that integrate left and right information to govern heart morphogenesis. This mechanism is conserved in the chicken embryo and, in the mouse, Snail1 fulfills the role played by Prrx1 in fish and chick. Thus, a differential L/R EMT produces asymmetric cell movements and forces, more prominent from the right, that drive heart laterality in vertebrates.
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Affiliation(s)
- Oscar H Ocaña
- Instituto de Neurociencias (CSIC-UMH), Avenida Ramón y Cajal, s/n, Sant Joan d'Alacant, Alicante, Spain
| | - Hakan Coskun
- Instituto de Neurociencias (CSIC-UMH), Avenida Ramón y Cajal, s/n, Sant Joan d'Alacant, Alicante, Spain
| | | | - Prayag Murawala
- DFG Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Fetscherstrasse 105, Dresden, Germany
| | - Elly M Tanaka
- DFG Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Fetscherstrasse 105, Dresden, Germany
| | - Joan Galcerán
- Instituto de Neurociencias (CSIC-UMH), Avenida Ramón y Cajal, s/n, Sant Joan d'Alacant, Alicante, Spain
| | - Ramón Muñoz-Chápuli
- University of Málaga, Department of Animal Biology, E-29071 Málaga, Spain.,Andalusian Center for Nanomedicine and Biotechnology (BIONAND), Málaga, Spain
| | - M Angela Nieto
- Instituto de Neurociencias (CSIC-UMH), Avenida Ramón y Cajal, s/n, Sant Joan d'Alacant, Alicante, Spain
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Beretta CA, Dross N, Engel U, Carl M. Tracking Cells in GFP-transgenic Zebrafish Using the Photoconvertible PSmOrange System. J Vis Exp 2016:e53604. [PMID: 26891031 DOI: 10.3791/53604] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The rapid development of transparent zebrafish embryos (Danio rerio) in combination with fluorescent labelings of cells and tissues allows visualizing developmental processes as they happen in the living animal. Cells of interest can be labeled by using a tissue specific promoter to drive the expression of a fluorescent protein (FP) for the generation of transgenic lines. Using fluorescent photoconvertible proteins for this purpose additionally allows to precisely follow defined structures within the expression domain. Illuminating the protein in the region of interest, changes its emission spectrum and highlights a particular cell or cell cluster leaving other transgenic cells in their original color. A major limitation is the lack of known promoters for a large number of tissues in the zebrafish. Conversely, gene- and enhancer trap screens have generated enormous transgenic resources discretely labeling literally all embryonic structures mostly with GFP or to a lesser extend red or yellow FPs. An approach to follow defined structures in such transgenic backgrounds would be to additionally introduce a ubiquitous photoconvertible protein, which could be converted in the cell(s) of interest. However, the photoconvertible proteins available involve a green and/or less frequently a red emission state and can therefore often not be used to track cells in the FP-background of existing transgenic lines. To circumvent this problem, we have established the PSmOrange system for the zebrafish. Simple microinjection of synthetic mRNA encoding a nuclear form of this protein labels all cell nuclei with orange/red fluorescence. Upon targeted photoconversion of the protein, it switches its emission spectrum to far red. The quantum efficiency and stability of the protein makes PSmOrange a superb cell-tracking tool for zebrafish and possibly other teleost species.
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Affiliation(s)
- Carlo A Beretta
- Medical Faculty Mannheim, Department of Cell and Molecular Biology, Heidelberg University; COS and Nikon Imaging Center at the University of Heidelberg, Heidelberg University; Excellenzcluster CellNetworks, University of Heidelberg
| | - Nicolas Dross
- COS and Nikon Imaging Center at the University of Heidelberg, Heidelberg University
| | - Ulrike Engel
- COS and Nikon Imaging Center at the University of Heidelberg, Heidelberg University
| | - Matthias Carl
- Medical Faculty Mannheim, Department of Cell and Molecular Biology, Heidelberg University;
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Nedosekin DA, Verkhusha VV, Melerzanov AV, Zharov VP, Galanzha EI. In vivo photoswitchable flow cytometry for direct tracking of single circulating tumor cells. CHEMISTRY & BIOLOGY 2014; 21:792-801. [PMID: 24816228 PMCID: PMC4174400 DOI: 10.1016/j.chembiol.2014.03.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Revised: 03/06/2014] [Accepted: 03/21/2014] [Indexed: 02/04/2023]
Abstract
Photoswitchable fluorescent proteins (PSFPs) that change their color in response to light have led to breakthroughs in studying static cells. However, using PSFPs to study cells in dynamic conditions is challenging. Here we introduce a method for in vivo ultrafast photoswitching of PSFPs that provides labeling and tracking of single circulating cells. Using in vivo multicolor flow cytometry, this method demonstrated the capability for studying recirculation, migration, and distribution of circulating tumor cells (CTCs) during metastasis progression. In tumor-bearing mice, it enabled monitoring of real-time dynamics of CTCs released from primary tumor, identifying dormant cells, and imaging of CTCs colonizing a primary tumor (self-seeding) or existing metastasis (reseeding). Integration of genetically encoded PSFPs, fast photoswitching, flow cytometry, and imaging makes in vivo single cell analysis in the circulation feasible to provide insights into the behavior of CTCs and potentially immune-related and bacterial cells in circulation.
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Affiliation(s)
- Dmitry A Nedosekin
- Winthrop P. Rockefeller Cancer Institute, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences (UAMS), 4301 West Markham, Little Rock, AR 72205, USA
| | - Vladislav V Verkhusha
- Department of Anatomy and Structural Biology and Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Alexander V Melerzanov
- Moscow Institute of Physics and Technology, 9 Inststitutskii pereulok, Dolgoprudny, Moscow Region 141700, Russian Federation
| | - Vladimir P Zharov
- Winthrop P. Rockefeller Cancer Institute, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences (UAMS), 4301 West Markham, Little Rock, AR 72205, USA; Moscow Institute of Physics and Technology, 9 Inststitutskii pereulok, Dolgoprudny, Moscow Region 141700, Russian Federation
| | - Ekaterina I Galanzha
- Winthrop P. Rockefeller Cancer Institute, Arkansas Nanomedicine Center, University of Arkansas for Medical Sciences (UAMS), 4301 West Markham, Little Rock, AR 72205, USA.
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Gfrerer L, Dougherty M, Liao EC. Visualization of craniofacial development in the sox10: kaede transgenic zebrafish line using time-lapse confocal microscopy. J Vis Exp 2013:e50525. [PMID: 24121214 DOI: 10.3791/50525] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Vertebrate palatogenesis is a highly choreographed and complex developmental process, which involves migration of cranial neural crest (CNC) cells, convergence and extension of facial prominences, and maturation of the craniofacial skeleton. To study the contribution of the cranial neural crest to specific regions of the zebrafish palate a sox10: kaede transgenic zebrafish line was generated. Sox10 provides lineage restriction of the kaede reporter protein to the neural crest, thereby making the cell labeling a more precise process than traditional dye or reporter mRNA injection. Kaede is a photo-convertible protein that turns from green to red after photo activation and makes it possible to follow cells precisely. The sox10: kaede transgenic line was used to perform lineage analysis to delineate CNC cell populations that give rise to maxillary versus mandibular elements and illustrate homology of facial prominences to amniotes. This protocol describes the steps to generate a live time-lapse video of a sox10: kaede zebrafish embryo. Development of the ethmoid plate will serve as a practical example. This protocol can be applied to making a time-lapse confocal recording of any kaede or similar photoconvertible reporter protein in transgenic zebrafish. Furthermore, it can be used to capture not only normal, but also abnormal development of craniofacial structures in the zebrafish mutants.
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Affiliation(s)
- Lisa Gfrerer
- Center for Regenerative Medicine, Massachusetts General Hospital
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