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Gómez Sánchez A, Colucci P, Moran A, Moya López A, Colligris B, Álvarez Y, Kennedy BN. Systemic treatment with cigarette smoke extract affects zebrafish visual behaviour, intraocular vasculature morphology and outer segment phagocytosis. OPEN RESEARCH EUROPE 2023; 3:48. [PMID: 38283058 PMCID: PMC10822043 DOI: 10.12688/openreseurope.15491.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 11/21/2023] [Indexed: 01/30/2024]
Abstract
Introduction Cigarette smoking adversely affects multiple aspects of human health including eye disorders such as age-related macular degeneration, cataracts and dry eye disease. However, there remains a knowledge gap in how constituents of cigarette smoke affect vision and retinal biology. We used zebrafish to assess effects of short-term acute exposure to cigarette smoke extract (CSE) on visual behaviour and retinal biology. Methods Zebrafish larvae with a developed visual system at three days post-fertilization (dpf) were exposed to CSE for 4, 24 or 48 hours. Visual behaviour, hyaloid vasculature morphology, retinal histology, oxidative stress gene expression and outer segment phagocytosis were investigated using visual behavioural optokinetic and visual motor response assays (OKR and VMR), microscopy (light, fluorescence and transmission electron microscopy), and real-time PCR. Results In zebrafish larvae, 48 hours of CSE treatment resulted in significantly reduced visual behaviour. Larvae treated with 10, 15 or 20 μg/mL CSE showed an average of 13.7, 10.7 or 9.4 saccades per minute, respectively, significantly lower compared with 0.05% DMSO controls (p=0.0093, p=0.0004 and p<0.0001, respectively) that exhibited 19.7 saccades per minute. The diameter of intraocular vessels increased from 4.833 μm in 0.05% DMSO controls to 5.885 μm in the 20 μg/mL CSE-treated larvae (p=0.0333). Biometry analysis highlighted a significant axial length elongation in 20 μg/mL CSE-treated larvae (216.9 μm, p<0.0001) compared to 0.05% dimethyl sulfoxide (DMSO) controls (205.1 μm). Larvae exposed to 20 μg/mL CSE had significantly (p=0.0002) higher numbers of RPE phagosomes compared to vehicle controls (0.1425 and 0.093 phagosomes/μm RPE, respectively). Conclusions Zebrafish larvae with a developed visual system display apparent defects in visual behaviour and retinal biology after acute exposure to CSE, establishing a valuable in vivo model to investigate ocular disorders related to cigarette smoke.
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Affiliation(s)
- Alicia Gómez Sánchez
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, D04 V1W8, Ireland
- Ocupharm Diagnostic Group Research, Faculty of Optic and Optometry, Complutense University of Madrid, Madrid, Spain
| | - Patrizia Colucci
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, D04 V1W8, Ireland
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, Siena, Italy
| | - Ailis Moran
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Alexandro Moya López
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, D04 V1W8, Ireland
- Ocupharm Diagnostic Group Research, Faculty of Optic and Optometry, Complutense University of Madrid, Madrid, Spain
| | - Basilio Colligris
- Ocupharm Diagnostic Group Research, Faculty of Optic and Optometry, Complutense University of Madrid, Madrid, Spain
| | - Yolanda Álvarez
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, D04 V1W8, Ireland
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, D04 V1W8, Ireland
| | - Breandán N. Kennedy
- UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Dublin, D04 V1W8, Ireland
- UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, D04 V1W8, Ireland
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2
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Casey MA, Lusk S, Kwan KM. Eye Morphogenesis in Vertebrates. Annu Rev Vis Sci 2023; 9:221-243. [PMID: 37040791 DOI: 10.1146/annurev-vision-100720-111125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Proper eye structure is essential for visual function: Multiple essential eye tissues must take shape and assemble into a precise three-dimensional configuration. Accordingly, alterations to eye structure can lead to pathological conditions of visual impairment. Changes in eye shape can also be adaptive over evolutionary time. Eye structure is first established during development with the formation of the optic cup, which contains the neural retina, retinal pigment epithelium, and lens. This crucial yet deceptively simple hemispherical structure lays the foundation for all later elaborations of the eye. Building on descriptions of the embryonic eye that started with hand drawings and micrographs, the field is beginning to identify mechanisms driving dynamic changes in three-dimensional cell and tissue shape. A combination of molecular genetics, imaging, and pharmacological approaches is defining connections among transcription factors, signaling pathways, and the intracellular machinery governing the emergence of this crucial structure.
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Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA; , ,
| | - Sarah Lusk
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA; , ,
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA; , ,
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Seese SE, Muheisen S, Gath N, Gross JM, Semina EV. Identification of HSPA8 as an interacting partner of MAB21L2 and an important factor in eye development. Dev Dyn 2023; 252:510-526. [PMID: 36576422 PMCID: PMC10947772 DOI: 10.1002/dvdy.560] [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: 06/19/2022] [Revised: 11/04/2022] [Accepted: 11/18/2022] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Pathogenic variants in human MAB21L2 result in microphthalmia, anophthalmia, and coloboma. The exact molecular function of MAB21L2 is currently unknown. We conducted a series of yeast two-hybrid (Y2H) experiments to determine protein interactomes of normal human and zebrafish MAB21L2/mab21l2 as well as human disease-associated variant MAB21L2-p.(Arg51Gly) using human adult retina and zebrafish embryo libraries. RESULTS These screens identified klhl31, tnpo1, TNPO2/tnpo2, KLC2/klc2, and SPTBN1/sptbn1 as co-factors of MAB21L2/mab21l2. Several factors, including hspa8 and hspa5, were found to interact with MAB21L2-p.Arg51Gly but not wild-type MAB21L2/mab21l2 in Y2H screens. Further analyses via 1-by-1 Y2H assays, co-immunoprecipitation, and mass spectrometry revealed that both normal and variant MAB21L2 interact with HSPA5 and HSPA8. In situ hybridization detected co-expression of hspa5 and hspa8 with mab21l2 during eye development in zebrafish. Examination of zebrafish mutant hspa8hi138Tg identified reduced hspa8 expression associated with severe ocular developmental defects, including small eye, coloboma, and anterior segment dysgenesis. To investigate the effects of hspa8 deficiency on the mab21l2Arg51_Phe52del allele, corresponding zebrafish double mutants were generated and found to be more severely affected than single mutant lines. CONCLUSION This study identifies heat shock proteins as interacting partners of MAB21L2/mab21l2 and suggests a role for this interaction in vertebrate eye development.
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Affiliation(s)
- Sarah E. Seese
- Department of Pediatrics The Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Cell Biology, Neurobiology and Anatomy, The Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Sanaa Muheisen
- Department of Pediatrics The Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Natalie Gath
- University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Jeffrey M. Gross
- University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Elena V. Semina
- Department of Pediatrics The Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Cell Biology, Neurobiology and Anatomy, The Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Children’s of Wisconsin, Milwaukee, WI 53226, USA
- Children’s Research Institute, Medical College of Wisconsin, Children’s of Wisconsin, Milwaukee, WI 53226, USA
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4
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Paidi SK, Zhang Q, Yang Y, Xia CH, Ji N, Gong X. Adaptive optical two-photon fluorescence microscopy probes cellular organization of ocular lenses in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.17.524320. [PMID: 36711806 PMCID: PMC9882239 DOI: 10.1101/2023.01.17.524320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The mammalian ocular lens is an avascular multicellular organ that grows continuously throughout life. Traditionally, its cellular organization is investigated using dissected lenses, which eliminates in vivo environmental and structural support. Here, we demonstrated that two-photon fluorescence microscopy (2PFM) can visualize lens cells in vivo. To maintain subcellular resolution at depth, we employed adaptive optics (AO) to correct aberrations due to ocular and lens tissues, which led to substantial signal and resolution improvements. Imaging lens cells up to 980 μm deep, we observed novel cellular organizations including suture-associated voids, enlarged vacuoles, and large cavities, contrary to the conventional view of a highly ordered organization. We tracked these features longitudinally over weeks and observed the incorporation of new cells during growth. Taken together, non-invasive longitudinal in vivo imaging of lens morphology using AO 2PFM will allow us to directly observe the development or alterations of lens cellular organization in living animals.
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Affiliation(s)
- Santosh Kumar Paidi
- School of Optometry, University of California, Berkeley, California 94720, USA
| | - Qinrong Zhang
- Department of Physics, University of California, Berkeley, California 94720, USA,Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Yuhan Yang
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - Chun-Hong Xia
- School of Optometry, University of California, Berkeley, California 94720, USA,Vision Science Program, University of California, Berkeley, California 94720, USA
| | - Na Ji
- Department of Physics, University of California, Berkeley, California 94720, USA,Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA,Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA,Corresponding authors: Xiaohua Gong () and Na Ji ()
| | - Xiaohua Gong
- School of Optometry, University of California, Berkeley, California 94720, USA,Vision Science Program, University of California, Berkeley, California 94720, USA,Corresponding authors: Xiaohua Gong () and Na Ji ()
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5
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Yang G, Wang L, Qin X, Chen X, Liang Y, Jin X, Chen C, Zhang W, Pan W, Li H. Heterogeneities of zebrafish vasculature development studied by a high throughput light-sheet flow imaging system. BIOMEDICAL OPTICS EXPRESS 2022; 13:5344-5357. [PMID: 36425637 PMCID: PMC9664872 DOI: 10.1364/boe.470058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/17/2022] [Accepted: 08/30/2022] [Indexed: 06/16/2023]
Abstract
Zebrafish is one of the ideal model animals to study the structural and functional heterogeneities in development. However, the lack of high throughput 3D imaging techniques has limited studies to only a few samples, despite zebrafish spawning tens of embryos at once. Here, we report a light-sheet flow imaging system (LS-FIS) based on light-sheet illumination and a continuous flow imager. LS-FIS enables whole-larva 3D imaging of tens of samples within half an hour. The high throughput 3D imaging capability of LS-FIS was demonstrated with the developmental study of the zebrafish vasculature from 3 to 9 days post-fertilization. Statistical analysis shows significant variances in trunk vessel development but less in hyaloid vessel development.
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Affiliation(s)
- Guang Yang
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou 215163, China
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Linbo Wang
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou 215163, China
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Xiaofei Qin
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Xiaohu Chen
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Yong Liang
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou 215163, China
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Xin Jin
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Chong Chen
- School of Biomedical Engineering (Suzhou), Division of Life Sciences and Medicine, University of Science and Technology of China, Suzhou 215163, China
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
| | - Wenjuan Zhang
- Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai 200031, China
| | - Weijun Pan
- Shanghai Institute of Nutrition and Health, Chinese Academy of Sciences, Shanghai 200031, China
| | - Hui Li
- Jiangsu Key Laboratory of Medical Optics,
Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou 215163, China
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Yoon B, Yeung P, Santistevan N, Bluhm LE, Kawasaki K, Kueper J, Dubielzig R, VanOudenhove J, Cotney J, Liao EC, Grinblat Y. Zebrafish models of alx-linked frontonasal dysplasia reveal a role for Alx1 and Alx3 in the anterior segment and vasculature of the developing eye. Biol Open 2022; 11:bio059189. [PMID: 35142342 PMCID: PMC9167625 DOI: 10.1242/bio.059189] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 01/28/2022] [Indexed: 11/18/2022] Open
Abstract
The cellular and genetic mechanisms that coordinate formation of facial sensory structures with surrounding skeletal and soft tissue elements remain poorly understood. Alx1, a homeobox transcription factor, is a key regulator of midfacial morphogenesis. ALX1 mutations in humans are linked to severe congenital anomalies of the facial skeleton (frontonasal dysplasia, FND) with malformation or absence of eyes and orbital contents (micro- and anophthalmia). Zebrafish with loss-of-function alx1 mutations develop with craniofacial and ocular defects of variable penetrance, likely due to compensatory upregulation in expression of a paralogous gene, alx3. Here we show that zebrafish alx1;alx3 mutants develop with highly penetrant cranial and ocular defects that resemble human ALX1-linked FND. alx1 and alx3 are expressed in anterior cranial neural crest (aCNC), which gives rise to the anterior neurocranium (ANC), anterior segment structures of the eye and vascular pericytes. Consistent with a functional requirement for alx genes in aCNC, alx1; alx3 mutants develop with nearly absent ANC and grossly aberrant hyaloid vasculature and ocular anterior segment, but normal retina. In vivo lineage labeling identified a requirement for alx1 and alx3 during aCNC migration, and transcriptomic analysis suggested oxidative stress response as a key target mechanism of this function. Oxidative stress is a hallmark of fetal alcohol toxicity, and we found increased penetrance of facial and ocular malformations in alx1 mutants exposed to ethanol, consistent with a protective role for alx1 against ethanol toxicity. Collectively, these data demonstrate a conserved role for zebrafish alx genes in controlling ocular and facial development, and a novel role in protecting these key midfacial structures from ethanol toxicity during embryogenesis. These data also reveal novel roles for alx genes in ocular anterior segment formation and vascular development and suggest that retinal deficits in alx mutants may be secondary to aberrant ocular vascularization and anterior segment defects. This study establishes robust zebrafish models for interrogating conserved genetic mechanisms that coordinate facial and ocular development, and for exploring gene--environment interactions relevant to fetal alcohol syndrome.
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Affiliation(s)
- Baul Yoon
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
- Genetics Ph.D. Training Program, University of Wisconsin, Madison, WI 53706, USA
| | - Pan Yeung
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
| | - Nicholas Santistevan
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
- Genetics Ph.D. Training Program, University of Wisconsin, Madison, WI 53706, USA
| | - Lauren E. Bluhm
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
| | - Kenta Kawasaki
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
| | - Janina Kueper
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
- Institute of Human Genetics, University of Bonn, Venusberg-Campus 1, 53127 Bonn, Germany
| | - Richard Dubielzig
- Comparative Ocular Pathology Laboratory of Wisconsin (COPLOW), University of Wisconsin, Madison, WI 53706, USA
| | - Jennifer VanOudenhove
- University of Connecticut School of Medicine, Department of Genetics and Genome Sciences, Farmington, CT 06030, USA
| | - Justin Cotney
- University of Connecticut School of Medicine, Department of Genetics and Genome Sciences, Farmington, CT 06030, USA
| | - Eric C. Liao
- Center for Regenerative Medicine, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, 02114, USA
| | - Yevgenya Grinblat
- Departments of Integrative Biology and Neuroscience, University of Wisconsin, Madison, WI 53706, USA
- Genetics Ph.D. Training Program, University of Wisconsin, Madison, WI 53706, USA
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7
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Ranawat N, Masai I. Mechanisms underlying microglial colonization of developing neural retina in zebrafish. eLife 2021; 10:70550. [PMID: 34872632 PMCID: PMC8651297 DOI: 10.7554/elife.70550] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 11/02/2021] [Indexed: 12/13/2022] Open
Abstract
Microglia are brain-resident macrophages that function as the first line of defense in brain. Embryonic microglial precursors originate in peripheral mesoderm and migrate into the brain during development. However, the mechanism by which they colonize the brain is incompletely understood. The retina is one of the first brain regions to accommodate microglia. In zebrafish, embryonic microglial precursors use intraocular hyaloid blood vessels as a pathway to migrate into the optic cup via the choroid fissure. Once retinal progenitor cells exit the cell cycle, microglial precursors associated with hyaloid blood vessels start to infiltrate the retina preferentially through neurogenic regions, suggesting that colonization of retinal tissue depends upon the neurogenic state. Along with blood vessels and retinal neurogenesis, IL34 also participates in microglial precursor colonization of the retina. Altogether, CSF receptor signaling, blood vessels, and neuronal differentiation function as cues to create an essential path for microglial migration into developing retina. The immune system is comprised of many different cells which protect our bodies from infection and other illnesses. The brain contains its own population of immune cells called microglia. Unlike neurons, these cells form outside the brain during development. They then travel to the brain and colonize specific regions like the retina, the light-sensing part of the eye in vertebrates. It is poorly understood how newly formed microglia migrate to the retina and whether their entry depends on the developmental state of nerve cells (also known as neurons) in this region. To help answer these questions, Ranawat and Masai attached fluorescent labels that can be seen under a microscope to microglia in the embryos of zebrafish. Developing zebrafish are transparent, making it easy to trace the fluorescent microglia as they travel to the retina and insert themselves among its neurons. Ranawat and Masai found that blood vessels around the retina act as a pathway that microglia move along. Once they reach the retina, the microglia remain attached and only enter the retina at sites where brain cells are starting to mature in to adult neurons. Further experiments showed that microglia fail to infiltrate and colonize the retina when blood vessels are damaged or neuron maturation is blocked. These findings reveal some of the key elements that guide microglia to the retina during development. However, further work is needed to establish the molecular and biochemical processes that allow microglia to attach to blood vessels and detect when cells in the retina are starting to mature.
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Affiliation(s)
- Nishtha Ranawat
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Japan
| | - Ichiro Masai
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Japan
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Lubin A, Otterstrom J, Hoade Y, Bjedov I, Stead E, Whelan M, Gestri G, Paran Y, Payne E. A versatile, automated and high-throughput drug screening platform for zebrafish embryos. Biol Open 2021; 10:bio058513. [PMID: 34472582 PMCID: PMC8430230 DOI: 10.1242/bio.058513] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 06/28/2021] [Indexed: 12/29/2022] Open
Abstract
Zebrafish provide a unique opportunity for drug screening in living animals, with the fast-developing, transparent embryos allowing for relatively high-throughput, microscopy-based screens. However, the limited availability of rapid, flexible imaging and analysis platforms has limited the use of zebrafish in drug screens. We have developed an easy-to-use, customisable automated screening procedure suitable for high-throughput phenotype-based screens of live zebrafish. We utilised the WiScan® Hermes High Content Imaging System to rapidly acquire brightfield and fluorescent images of embryos, and the WiSoft® Athena Zebrafish Application for analysis, which harnesses an Artificial Intelligence-driven algorithm to automatically detect fish in brightfield images, identify anatomical structures, partition the animal into regions and exclusively select the desired side-oriented fish. Our initial validation combined structural analysis with fluorescence images to enumerate GFP-tagged haematopoietic stem and progenitor cells in the tails of embryos, which correlated with manual counts. We further validated this system to assess the effects of genetic mutations and X-ray irradiation in high content using a wide range of assays. Further, we performed simultaneous analysis of multiple cell types using dual fluorophores in high throughput. In summary, we demonstrate a broadly applicable and rapidly customisable platform for high-content screening in zebrafish. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Alexandra Lubin
- Research Department of Haematology, Cancer Institute, University College London, London WC1E 6DD, UK
| | | | - Yvette Hoade
- Research Department of Haematology, Cancer Institute, University College London, London WC1E 6DD, UK
| | - Ivana Bjedov
- Research Department of Cancer Biology, Cancer Institute, University College London, London WC1E 6DD, UK
| | - Eleanor Stead
- Research Department of Cancer Biology, Cancer Institute, University College London, London WC1E 6DD, UK
| | - Matthew Whelan
- Division of Infection and Immunity, University College London, London WC1E 6BT, UK
| | - Gaia Gestri
- Department of Cell and Developmental Biology, University College London, London WC1E 6AR, UK
| | - Yael Paran
- IDEA Bio-Medical Ltd., Rehovot 76705, Israel
| | - Elspeth Payne
- Research Department of Haematology, Cancer Institute, University College London, London WC1E 6DD, UK
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9
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Ferre-Fernández JJ, Sorokina EA, Thompson S, Collery RF, Nordquist E, Lincoln J, Semina EV. Disruption of foxc1 genes in zebrafish results in dosage-dependent phenotypes overlapping Axenfeld-Rieger syndrome. Hum Mol Genet 2021; 29:2723-2735. [PMID: 32720677 DOI: 10.1093/hmg/ddaa163] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/16/2020] [Accepted: 07/21/2020] [Indexed: 12/14/2022] Open
Abstract
The Forkhead Box C1 (FOXC1) gene encodes a forkhead/winged helix transcription factor involved in embryonic development. Mutations in this gene cause dysgenesis of the anterior segment of the eye, most commonly Axenfeld-Rieger syndrome (ARS), often with other systemic features. The developmental mechanisms and pathways regulated by FOXC1 remain largely unknown. There are two conserved orthologs of FOXC1 in zebrafish, foxc1a and foxc1b. To further examine the role of FOXC1 in vertebrates, we generated foxc1a and foxc1b single knockout zebrafish lines and bred them to obtain various allelic combinations. Three genotypes demonstrated visible phenotypes: foxc1a-/- single homozygous and foxc1-/- double knockout homozygous embryos presented with similar characteristics comprised of severe global vascular defects and early lethality, as well as microphthalmia, periocular edema and absence of the anterior chamber of the eye; additionally, fish with heterozygous loss of foxc1a combined with homozygosity for foxc1b (foxc1a+/-;foxc1b-/-) demonstrated craniofacial defects, heart anomalies and scoliosis. All other single and combined genotypes appeared normal. Analysis of foxc1 expression detected a significant increase in foxc1a levels in homozygous and heterozygous mutant eyes, suggesting a mechanism for foxc1a upregulation when its function is compromised; interestingly, the expression of another ARS-associated gene, pitx2, was responsive to the estimated level of wild-type Foxc1a, indicating a possible role for this protein in the regulation of pitx2 expression. Altogether, our results support a conserved role for foxc1 in the formation of many organs, consistent with the features observed in human patients, and highlight the importance of correct FOXC1/foxc1 dosage for vertebrate development.
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Affiliation(s)
- Jesús-José Ferre-Fernández
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Elena A Sorokina
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Samuel Thompson
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Ross F Collery
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Emily Nordquist
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Joy Lincoln
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA.,Division of Pediatric Cardiology, Herma Heart Institute, Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Elena V Semina
- Department of Pediatrics, Children's Research Institute, Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA.,Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
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10
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Casey MA, Lusk S, Kwan KM. Build me up optic cup: Intrinsic and extrinsic mechanisms of vertebrate eye morphogenesis. Dev Biol 2021; 476:128-136. [PMID: 33811855 PMCID: PMC8848517 DOI: 10.1016/j.ydbio.2021.03.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 12/16/2022]
Abstract
The basic structure of the eye, which is crucial for visual function, is established during the embryonic process of optic cup morphogenesis. Molecular pathways of specification and patterning are integrated with spatially distinct cell and tissue shape changes to generate the eye, with discrete domains and structural features: retina and retinal pigment epithelium enwrap the lens, and the optic fissure occupies the ventral surface of the eye and optic stalk. Interest in the underlying cell biology of eye morphogenesis has led to a growing body of work, combining molecular genetics and imaging to quantify cellular processes such as adhesion and actomyosin activity. These studies reveal that intrinsic machinery and spatiotemporally specific extrinsic inputs collaborate to control dynamics of cell movements and morphologies. Here we consider recent advances in our understanding of eye morphogenesis, with a focus on the mechanics of eye formation throughout vertebrate systems, including insights and potential opportunities using organoids, which may provide a tractable system to test hypotheses from embryonic models.
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Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Sarah Lusk
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA.
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11
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Seese SE, Deml B, Muheisen S, Sorokina E, Semina EV. Genetic disruption of zebrafish mab21l1 reveals a conserved role in eye development and affected pathways. Dev Dyn 2021; 250:1056-1073. [PMID: 33570754 PMCID: PMC8349561 DOI: 10.1002/dvdy.312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 01/28/2021] [Accepted: 02/01/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The male-abnormal 21 like (MAB21L) genes are important in human ocular development. Homozygous loss of MAB21L1 leads to corneal dystrophy in all affected individuals along with cataracts and buphthalmos in some. The molecular function and downstream pathways of MAB21L factors are largely undefined. RESULTS We generated the first mab21l1 zebrafish mutant carrying a putative loss-of-function allele, c.107delA p.(Lys36Argfs*7). At the final stages of embryonic development, homozygous mab21l1c.107delA fish displayed enlarged anterior chambers and corneal thinning which progressed with age. Additional studies revealed increased cell death in the mutant corneas, transformation of the cornea into a skin-like epithelium, and progressive lens degeneration with development of fibrous masses in the anterior chamber. RNA-seq of wild-type and mutant ocular transcriptomes revealed significant changes in expression of several genes, including irf1a and b, stat1, elf3, krt17, tlr9, and loxa associated with immunity and/or corneal function. Abnormal expression of lysyl oxidases have been previously linked with corneal thinning, fibrosis, and lens defects in mammals, suggesting a role for loxa misexpression in the progressive mab21l1c.107delA eye phenotype. CONCLUSIONS Zebrafish mab21l1 is essential for normal corneal development, similar to human MAB21L1. The identified molecular changes in mab21l1c.107delA mutants provide the first clues about possible affected pathways.
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Affiliation(s)
- Sarah E. Seese
- Department of Pediatrics, The Medical College of Wisconsin, Milwaukee, Wisconsin
- Cell Biology, Neurobiology and Anatomy, The Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Brett Deml
- Department of Pediatrics, The Medical College of Wisconsin, Milwaukee, Wisconsin
- Cell Biology, Neurobiology and Anatomy, The Medical College of Wisconsin, Milwaukee, Wisconsin
- PreventionGenetics, Marshfield, Wisconsin
| | - Sanaa Muheisen
- Department of Pediatrics, The Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Elena Sorokina
- Department of Pediatrics, The Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Elena V. Semina
- Department of Pediatrics, The Medical College of Wisconsin, Milwaukee, Wisconsin
- Cell Biology, Neurobiology and Anatomy, The Medical College of Wisconsin, Milwaukee, Wisconsin
- Department of Ophthalmology and Visual Sciences, Medical College of Wisconsin, Children's of Wisconsin, Milwaukee, Wisconsin
- Children's Research Institute, Medical College of Wisconsin, Children's of Wisconsin, Milwaukee, Wisconsin
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12
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Hong Y, Luo Y. Zebrafish Model in Ophthalmology to Study Disease Mechanism and Drug Discovery. Pharmaceuticals (Basel) 2021; 14:ph14080716. [PMID: 34451814 PMCID: PMC8400593 DOI: 10.3390/ph14080716] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/14/2022] Open
Abstract
Visual impairment and blindness are common and seriously affect people’s work and quality of life in the world. Therefore, the effective therapies for eye diseases are of high priority. Zebrafish (Danio rerio) is an alternative vertebrate model as a useful tool for the mechanism elucidation and drug discovery of various eye disorders, such as cataracts, glaucoma, diabetic retinopathy, age-related macular degeneration, photoreceptor degeneration, etc. The genetic and embryonic accessibility of zebrafish in combination with a behavioral assessment of visual function has made it a very popular model in ophthalmology. Zebrafish has also been widely used in ocular drug discovery, such as the screening of new anti-angiogenic compounds or neuroprotective drugs, and the oculotoxicity test. In this review, we summarized the applications of zebrafish as the models of eye disorders to study disease mechanism and investigate novel drug treatments.
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Affiliation(s)
| | - Yan Luo
- Correspondence: ; Tel.: +86-020-87335931
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13
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Halabi R, Watterston C, Hehr CL, Mori-Kreiner R, Childs SJ, McFarlane S. Semaphorin 3fa Controls Ocular Vascularization From the Embryo Through to the Adult. Invest Ophthalmol Vis Sci 2021; 62:21. [PMID: 33595613 PMCID: PMC7900886 DOI: 10.1167/iovs.62.2.21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Purpose Pathological blood vessel growth in the eye is implicated in several diseases that result in vision loss, including age-related macular degeneration and diabetic retinopathy. The limits of current disease therapies have created the need to identify and characterize new antiangiogenic drugs. Here, we identify the secreted chemorepellent semaphorin-3fa (Sema3fa) as an endogenous anti-angiogenic in the eye. Methods We generated a CRISPR/Cas9 sema3fa zebrafish mutant line, sema3faca304/304. We assessed the retinal and choroidal vasculature in both larval and adult wild-type and sema3fa mutant zebrafish. Results We find sema3fa mRNA is expressed by the ciliary marginal zone, neural retina, and retinal pigment epithelium of zebrafish larvae as choroidal vascularization emerges and the hyaloid/retinal vasculature is remodeled. The hyaloid vessels of sema3fa mutants develop appropriately but fail to remodel during the larval period, with adult mutants exhibiting a denser network of capillaries in the retinal periphery than seen in wild-type. The choroid vasculature is also defective in that it develops precociously, and aberrant, leaky sprouts are present in the normally avascular outer retina of both sema3faca304/304 larvae and adult fish. Conclusions Sema3fa is a key endogenous signal for maintaining an avascular retina and preventing pathologic vascularization. Furthermore, we provide a new experimentally accessible model for studying choroid neovascularization (CNV) resulting from primary changes in the retinal environment that lead to downstream vessel infiltration.
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Affiliation(s)
- Rami Halabi
- Graduate Program in Neuroscience, University of Calgary, Calgary, Canada.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Charlene Watterston
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Carrie Lynn Hehr
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
| | - Risa Mori-Kreiner
- Graduate Program in Neuroscience, University of Calgary, Calgary, Canada.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
| | - Sarah J Childs
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
| | - Sarah McFarlane
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
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14
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Seese SE, Reis LM, Deml B, Griffith C, Reich A, Jamieson RV, Semina EV. Identification of missense MAB21L1 variants in microphthalmia and aniridia. Hum Mutat 2021; 42:877-890. [PMID: 33973683 PMCID: PMC8238893 DOI: 10.1002/humu.24218] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/29/2021] [Accepted: 04/27/2021] [Indexed: 12/14/2022]
Abstract
Microphthalmia, coloboma, and aniridia are congenital ocular phenotypes with a strong genetic component but often unknown cause. We present a likely causative novel variant in MAB21L1, c.152G>T p.(Arg51Leu), in two family members with microphthalmia and aniridia, as well as novel or rare compound heterozygous variants of uncertain significance, c.184C>T p.(Arg62Cys)/c.-68T>C, and c.658G>C p.(Gly220Arg)/c.*529A>G, in two additional probands with microphthalmia, coloboma and/or cataracts. All variants were predicted as damaging by in silico programs. In vitro studies of coding variants revealed normal subcellular localization but variable stability for the corresponding mutant proteins. In vivo complementation assays using the zebrafish mab21l2 Q48Sfs*5 loss-of-function line demonstrated that though overexpression of wild-type MAB21L1 messenger RNA (mRNA) compensated for the loss of mab21l2, none of the coding variant mRNAs produced a statistically significant rescue, with p.(Arg51Leu) showing the highest degree of functional deficiency. Dominant variants in a close homolog of MAB21L1, MAB21L2, have been associated with microphthalmia and/or coloboma and repeatedly involved the same Arg51 residue, further supporting its pathogenicity. The possible role of p.(Arg62Cys) and p.(Gly220Arg) in microphthalmia is similarly supported by the observed functional defects, with or without an additional impact from noncoding MAB21L1 variants identified in each patient. This study suggests a broader spectrum of MAB21L1-associated disease.
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Affiliation(s)
- Sarah E. Seese
- Department of Pediatrics and Children's Research Institute, Medical College of WisconsinChildren's of WisconsinMilwaukeeWIUSA
- Department of Cell Biology, Neurobiology, and AnatomyThe Medical College of WisconsinMilwaukeeWisconsinUSA
| | - Linda M. Reis
- Department of Pediatrics and Children's Research Institute, Medical College of WisconsinChildren's of WisconsinMilwaukeeWIUSA
| | - Brett Deml
- Department of Pediatrics and Children's Research Institute, Medical College of WisconsinChildren's of WisconsinMilwaukeeWIUSA
- Present address:
PreventionGeneticsMarshfieldWisconsinUSA
| | | | | | - Robyn V. Jamieson
- Eye Genetics Research Unit, Sydney Children's Hospitals Network and Children's Medical Research InstituteUniversity of SydneySydneyNew South WalesAustralia
| | - Elena V. Semina
- Department of Pediatrics and Children's Research Institute, Medical College of WisconsinChildren's of WisconsinMilwaukeeWIUSA
- Department of Cell Biology, Neurobiology, and AnatomyThe Medical College of WisconsinMilwaukeeWisconsinUSA
- Department of Ophthalmology and Visual SciencesMedical College of WisconsinMilwaukeeWisconsinUSA
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15
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Dhakal S, Rotem-Bamberger S, Sejd JR, Sebbagh M, Ronin N, Frey RA, Beitsch M, Batty M, Taler K, Blackerby JF, Inbal A, Stenkamp DL. Selective Requirements for Vascular Endothelial Cells and Circulating Factors in the Regulation of Retinal Neurogenesis. Front Cell Dev Biol 2021; 9:628737. [PMID: 33898420 PMCID: PMC8060465 DOI: 10.3389/fcell.2021.628737] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 03/17/2021] [Indexed: 01/01/2023] Open
Abstract
Development of the vertebrate eye requires signaling interactions between neural and non-neural tissues. Interactions between components of the vascular system and the developing neural retina have been difficult to decipher, however, due to the challenges of untangling these interactions from the roles of the vasculature in gas exchange. Here we use the embryonic zebrafish, which is not yet reliant upon hemoglobin-mediated oxygen transport, together with genetic strategies for (1) temporally-selective depletion of vascular endothelial cells, (2) elimination of blood flow through the circulation, and (3) elimination of cells of the erythroid lineage, including erythrocytes. The retinal phenotypes in these genetic systems were not identical, with endothelial cell-depleted retinas displaying laminar disorganization, cell death, reduced proliferation, and reduced cell differentiation. In contrast, the lack of blood flow resulted in a milder retinal phenotype showing reduced proliferation and reduced cell differentiation, indicating that an endothelial cell-derived factor(s) is/are required for laminar organization and cell survival. The lack of erythrocytes did not result in an obvious retinal phenotype, confirming that defects in retinal development that result from vascular manipulations are not due to poor gas exchange. These findings underscore the importance of the cardiovascular system supporting and controlling retinal development in ways other than supplying oxygen. In addition, these findings identify a key developmental window for these interactions and point to distinct functions for vascular endothelial cells vs. circulating factors.
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Affiliation(s)
- Susov Dhakal
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Shahar Rotem-Bamberger
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Josilyn R Sejd
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Meyrav Sebbagh
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Nathan Ronin
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ruth A Frey
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
| | - Mya Beitsch
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Megan Batty
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States.,Department of Biology, Gonzaga University, Spokane, WA, United States
| | - Kineret Taler
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Jennifer F Blackerby
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States.,Department of Biology, Gonzaga University, Spokane, WA, United States
| | - Adi Inbal
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Deborah L Stenkamp
- Department of Biological Sciences, University of Idaho, Moscow, ID, United States
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16
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Cassar S, Dunn C, Ramos MF. Zebrafish as an Animal Model for Ocular Toxicity Testing: A Review of Ocular Anatomy and Functional Assays. Toxicol Pathol 2020; 49:438-454. [PMID: 33063651 DOI: 10.1177/0192623320964748] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Xenobiotics make their way into organisms from diverse sources including diet, medication, and pollution. Our understanding of ocular toxicities from xenobiotics in humans, livestock, and wildlife is growing thanks to laboratory animal models. Anatomy and physiology are conserved among vertebrate eyes, and studies with common mammalian preclinical species (rodent, dog) can predict human ocular toxicity. However, since the eye is susceptible to toxicities that may not involve a histological correlate, and these species rely heavily on smell and hearing to navigate their world, discovering visual deficits can be challenging with traditional animal models. Alternative models capable of identifying functional impacts on vision and requiring minimal amounts of chemical are valuable assets to toxicology. Human and zebrafish eyes are anatomically and functionally similar, and it has been reported that several common human ocular toxicants cause comparable toxicity in zebrafish. Vision develops rapidly in zebrafish; the tiny larvae rely on visual cues as early as 4 days, and behavioral responses to those cues can be monitored in high-throughput fashion. This article describes the comparative anatomy of the zebrafish eye, the notable differences from the mammalian eye, and presents practical applications of this underutilized model for assessment of ocular toxicity.
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Affiliation(s)
- Steven Cassar
- Preclinical Safety, 419726AbbVie, Inc, North Chicago, IL, USA
| | - Christina Dunn
- Preclinical Safety, 419726AbbVie, Inc, North Chicago, IL, USA
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17
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Weaver ML, Piedade WP, Meshram NN, Famulski JK. Hyaloid vasculature and mmp2 activity play a role during optic fissure fusion in zebrafish. Sci Rep 2020; 10:10136. [PMID: 32576859 PMCID: PMC7311462 DOI: 10.1038/s41598-020-66451-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 05/18/2020] [Indexed: 02/03/2023] Open
Abstract
Vertebrate retinal development requires timely and precise fusion of the optic fissure (OF). Failure of this event leads to congenital vision impairment in the form of coloboma. Recent studies have suggested hyaloid vasculature to be involved in OF fusion. In order to examine this link, we analyzed OF fusion and hyaloid vasculogenesis in the zebrafish pax2a noi mutant line. We first determined that pax2a-/- embryos fail to accumulate F-actin in the OF prior to basement membrane (BM) degradation. Furthermore, using 3D and live imaging we observed reduced OF hyaloid vascularization in pax2a-/- embryos. When examining the connection between pax2a loss of function and hyaloid vasculature, we observed significant reduction of talin1 expression, a regulator of hyaloid vasculature. In addition, cranial VEGF expression was found to be reduced in pax2a-/- embryos. Pharmacological inhibition of VEGF signaling phenocopied the pax2a-/- vasculature, F-actin and BM degradation phenotypes. Lastly, we determined that OF associated hyaloid vasculature is a source of mmp2, mmp14a and mmp14b expression and showed that mmp2 is functionally necessary for degradation of OF BM. Taken together we propose a pax2a driven mechanism that ensures proper and timely hyaloid vasculature invasion of the OF in order to facilitate availability of the BM remodeler mmp2.
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Affiliation(s)
- Megan L Weaver
- Department of Biology, University of Kentucky, Lexington, KY, USA
| | - Warlen P Piedade
- Department of Biology, University of Kentucky, Lexington, KY, USA
| | | | - Jakub K Famulski
- Department of Biology, University of Kentucky, Lexington, KY, USA.
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18
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Blume ZI, Lambert JM, Lovel AG, Mitchell DM. Microglia in the developing retina couple phagocytosis with the progression of apoptosis via P2RY12 signaling. Dev Dyn 2020; 249:723-740. [PMID: 32072708 DOI: 10.1002/dvdy.163] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 12/30/2019] [Accepted: 02/07/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Microglia colonize the developing vertebrate central nervous system coincident with the detection of developmental apoptosis. Our understanding of apoptosis in intact tissue in relation to microglial clearance of dying cells is largely based on fixed samples, which is limiting given that microglia are highly motile and mobile phagocytes. Here, we used a system of microglial depletion and in vivo real-time imaging in zebrafish to directly address microglial phagocytosis of apoptotic cells during normal retinal development, the relative timing of phagocytosis in relation to apoptotic progression, and the contribution of P2RY12 signaling to this process. RESULTS The depletion of microglia resulted in accumulation of numerous apoptotic cells in the retina. Real-time imaging revealed precise timing of microglial engulfment with the progression of apoptosis, and dynamic movement and displacement of engulfed apoptotic cells. Inhibition of P2RY12 signaling delayed microglial clearance of apoptotic cells. CONCLUSIONS Microglial engulfment of dying cells is coincident with apoptotic progression and requires P2RY12 signaling, indicating that microglial P2RY12 signaling is shared between development and injury response. Our work provides important in vivo insight into the dynamics of apoptotic cell clearance in the developing vertebrate retina and provides a basis to understand microglial phagocytic behavior in health and disease.
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Affiliation(s)
- Zachary I Blume
- Biological Sciences, University of Idaho, Moscow, Idaho, USA
| | - Jared M Lambert
- Biological Sciences, University of Idaho, Moscow, Idaho, USA
| | - Anna G Lovel
- Biological Sciences, University of Idaho, Moscow, Idaho, USA
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19
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Caceres L, Prykhozhij SV, Cairns E, Gjerde H, Duff NM, Collett K, Ngo M, Nasrallah GK, McMaster CR, Litvak M, Robitaille JM, Berman JN. Frizzled 4 regulates ventral blood vessel remodeling in the zebrafish retina. Dev Dyn 2019; 248:1243-1256. [PMID: 31566834 DOI: 10.1002/dvdy.117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 09/04/2019] [Accepted: 09/06/2019] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Familial exudative vitreoretinopathy (FEVR) is a rare congenital disorder characterized by a lack of blood vessel growth to the periphery of the retina with secondary fibrovascular proliferation at the vascular-avascular junction. These structurally abnormal vessels cause leakage and hemorrhage, while the fibroproliferative scarring results in retinal dragging, detachment and blindness. Mutations in the FZD4 gene represent one of the most common causes of FEVR. METHODS A loss of function mutation resulting from a 10-nucleotide insertion into exon 1 of the zebrafish fzd4 gene was generated using transcription activator-like effector nucleases (TALENs). Structural and functional integrity of the retinal vasculature was examined by fluorescent microscopy and optokinetic responses. RESULTS Zebrafish retinal vasculature is asymmetrically distributed along the dorsoventral axis, with active vascular remodeling on the ventral surface of the retina throughout development. fzd4 mutants exhibit disorganized ventral retinal vasculature with discernable tubular fusion by week 8 of development. Furthermore, fzd4 mutants have impaired optokinetic responses requiring increased illumination. CONCLUSION We have generated a visually impaired zebrafish FEVR model exhibiting abnormal retinal vasculature. These fish provide a tractable system for studying vascular biology in retinovascular disorders, and demonstrate the feasibility of using zebrafish for evaluating future FEVR genes identified in humans.
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Affiliation(s)
- Lucia Caceres
- Department of Pediatrics, IWK Health Centre/Dalhousie University, Halifax, Nova Scotia, Canada
| | - Sergey V Prykhozhij
- Department of Pediatrics, IWK Health Centre/Dalhousie University, Halifax, Nova Scotia, Canada
| | - Elizabeth Cairns
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Harald Gjerde
- Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Nicole M Duff
- Department of Biology, Mount Allison University, Sackville, New Brunswick, Canada
| | - Keon Collett
- Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Mike Ngo
- Department of Pharmacology, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | | | - Matthew Litvak
- Department of Biology, Mount Allison University, Sackville, New Brunswick, Canada
| | - Johane M Robitaille
- Department of Pediatrics, IWK Health Centre/Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Jason N Berman
- Department of Pediatrics, IWK Health Centre/Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia, Canada.,Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, Ontario, Canada
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20
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Ohnesorge N, Sasore T, Hillary D, Alvarez Y, Carey M, Kennedy BN. Orthogonal Drug Pooling Enhances Phenotype-Based Discovery of Ocular Antiangiogenic Drugs in Zebrafish Larvae. Front Pharmacol 2019; 10:508. [PMID: 31178719 PMCID: PMC6544088 DOI: 10.3389/fphar.2019.00508] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 04/24/2019] [Indexed: 12/11/2022] Open
Abstract
Unbiased screening of large randomized chemical libraries in vivo is a powerful tool to find new drugs and targets. However, forward chemical screens in zebrafish can be time consuming and usually >99% of test compounds have no significant effect on the desired phenotype. Here, we sought to find bioactive drugs more efficiently and to comply with the 3R principles of replacement, reduction, and refinement of animals in research. We investigated if pooling of drugs to simultaneously test 8–10 compounds in zebrafish larvae can increase the screening efficiency of an established assay that identifies drugs inhibiting developmental angiogenesis in the eye. In a phenotype-based screen, we tested 1,760 small molecule compounds from the ChemBridge DIVERSet™ chemical library for their ability to inhibit the formation of distinct primary hyaloid vessels in the eye. Applying orthogonal pooling of the chemical library, we treated zebrafish embryos from 3 to 5 days post fertilization with pools of 8 or 10 compounds at 10 μM each. This reduced the number of tests from 1,760 to 396. In 63% of cases, treatment showed sub-threshold effects of <40% reduction of primary hyaloid vessels. From 18 pool hits, we identified eight compounds that reduce hyaloid vessels in the larval zebrafish eye by at least 40%. Compound 4-[4-(1H-benzimidazol-2-yl)phenoxy]aniline ranked as the most promising candidate with reproducible and dose-dependent effects. To our knowledge, this is the first report of a self-deconvoluting matrix strategy applied to drug screening in zebrafish. We conclude that the orthogonal drug pooling strategy is a cost-effective, time-saving, and unbiased approach to discover novel inhibitors of developmental angiogenesis in the eye. Ultimately, this approach may identify new drugs or targets to mitigate disease caused by pathological angiogenesis in the eye, e.g., diabetic retinopathy or age-related macular degeneration, wherein blood vessel growth and leaky vessels lead to vision impairment or clinical blindness.
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Affiliation(s)
- Nils Ohnesorge
- UCD School of Biomolecular and Biomedical Sciences, and UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Temitope Sasore
- UCD School of Biomolecular and Biomedical Sciences, and UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Daniel Hillary
- School of Mathematics & Statistics, University College Dublin, Dublin, Ireland
| | - Yolanda Alvarez
- UCD School of Biomolecular and Biomedical Sciences, and UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Michelle Carey
- School of Mathematics & Statistics, University College Dublin, Dublin, Ireland
| | - Breandán N Kennedy
- UCD School of Biomolecular and Biomedical Sciences, and UCD Conway Institute, University College Dublin, Dublin, Ireland
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21
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Gath N, Gross JM. Zebrafish mab21l2 mutants possess severe defects in optic cup morphogenesis, lens and cornea development. Dev Dyn 2019; 248:514-529. [PMID: 31037784 DOI: 10.1002/dvdy.44] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/09/2019] [Accepted: 04/16/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Mutations in MAB21L2 result in severe ocular defects including microphthalmia, anophthalmia, coloboma, microcornea, and cataracts. The molecular and cellular underpinnings of these defects are unknown, as is the normal cellular function of MAB21L2. Zebrafish mab21l2 au10 mutants possess ocular defects resembling those in humans with MAB21L2 mutations, providing an excellent model to characterize mab21l2 functions during eye development. RESULTS mab21l2 -/- mutants possessed a host of ocular defects including microphthalmia and colobomas as well as small, disorganized lenses and cornea dysgenesis. Decreased proliferation, increased cell death, and defects in marker gene expression were detected in the lens. Cell death in the optic stalk was elevated in mab21l2 -/- mutants and the basement membrane between the edges of the choroid fissure failed to break down. Neuronal differentiation in the retina was normal, however. mab21l2 -/- mutant corneas were disorganized, possessed an increased number of cells, some of which proliferated ectopically, and failed to differentiate the corneal stroma. CONCLUSIONS mab21l2 function is required for morphogenesis and cell survival in the lens and optic cup, and basement membrane breakdown in the choroid fissure. mab21l2 function also regulates proliferation in the lens and cornea; in its absence, the lens is small and mispatterned, and corneal morphogenesis and patterning are also disrupted.
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Affiliation(s)
- Natalie Gath
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas.,Departments of Ophthalmology and Developmental Biology, Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Jeffrey M Gross
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas.,Departments of Ophthalmology and Developmental Biology, Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
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22
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Transcriptome profiling of zebrafish optic fissure fusion. Sci Rep 2019; 9:1541. [PMID: 30733552 PMCID: PMC6367446 DOI: 10.1038/s41598-018-38379-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 12/27/2018] [Indexed: 01/06/2023] Open
Abstract
Incomplete fusion of the optic fissure leads to ocular coloboma, a congenital eye defect that affects up to 7.5 per 10,000 births and accounts for up to 10 percent of childhood blindness. The molecular and cellular mechanisms that facilitate optic fissure fusion remain elusive. We have profiled global gene expression during optic fissure morphogenesis by transcriptome analysis of tissue dissected from the margins of the zebrafish optic fissure and the opposing dorsal retina before (32 hours post fertilisation, hpf), during (48 hpf) and after (56 hpf) optic fissure fusion. Differential expression analysis between optic fissure and dorsal retinal tissue resulted in the detection of several known and novel developmental genes. The expression of selected genes was validated by qRT-PCR analysis and localisation investigated using in situ hybridisation. We discuss significantly overrepresented functional ontology categories in the context of optic fissure morphogenesis and highlight interesting transcripts from hierarchical clustering for subsequent analysis. We have identified netrin1a (ntn1a) as highly differentially expressed across optic fissure fusion, with a resultant ocular coloboma phenotype following morpholino antisense translation-blocking knockdown and downstream disruption of atoh7 expression. To support the identification of candidate genes in human studies, we have generated an online open-access resource for fast and simple quantitative querying of the gene expression data. Our study represents the first comprehensive analysis of the zebrafish optic fissure transcriptome and provides a valuable resource to facilitate our understanding of the complex aetiology of ocular coloboma.
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23
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Sribudiani Y, Chauhan RK, Alves MM, Petrova L, Brosens E, Harrison C, Wabbersen T, de Graaf BM, Rügenbrink T, Burzynski G, Brouwer RWW, van IJcken WFJ, Maas SM, de Klein A, Osinga J, Eggen BJL, Burns AJ, Brooks AS, Shepherd IT, Hofstra RMW. Identification of Variants in RET and IHH Pathway Members in a Large Family With History of Hirschsprung Disease. Gastroenterology 2018; 155:118-129.e6. [PMID: 29601828 DOI: 10.1053/j.gastro.2018.03.034] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 02/22/2018] [Accepted: 03/19/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND & AIMS Hirschsprung disease (HSCR) is an inherited congenital disorder characterized by absence of enteric ganglia in the distal part of the gut. Variants in ret proto-oncogene (RET) have been associated with up to 50% of familial and 35% of sporadic cases. We searched for variants that affect disease risk in a large, multigenerational family with history of HSCR in a linkage region previously associated with the disease (4q31.3-q32.3) and exome wide. METHODS We performed exome sequencing analyses of a family in the Netherlands with 5 members diagnosed with HSCR and 2 members diagnosed with functional constipation. We initially focused on variants in genes located in 4q31.3-q32.3; however, we also performed an exome-wide analysis in which known HSCR or HSCR-associated gene variants predicted to be deleterious were prioritized for further analysis. Candidate genes were expressed in HEK293, COS-7, and Neuro-2a cells and analyzed by luciferase and immunoblot assays. Morpholinos were designed to target exons of candidate genes and injected into 1-cell stage zebrafish embryos. Embryos were allowed to develop and stained for enteric neurons. RESULTS Within the linkage region, we identified 1 putative splice variant in the lipopolysaccharide responsive beige-like anchor protein gene (LRBA). Functional assays could not confirm its predicted effect on messenger RNA splicing or on expression of the mab-21 like 2 gene (MAB21L2), which is embedded in LRBA. Zebrafish that developed following injection of the lrba morpholino had a shortened body axis and subtle gut morphological defects, but no significant reduction in number of enteric neurons compared with controls. Outside the linkage region, members of 1 branch of the family carried a previously unidentified RET variant or an in-frame deletion in the glial cell line derived neurotrophic factor gene (GDNF), which encodes a ligand of RET. This deletion was located 6 base pairs before the last codon. We also found variants in the Indian hedgehog gene (IHH) and its mediator, the transcription factor GLI family zinc finger 3 (GLI3). When expressed in cells, the RET-P399L variant disrupted protein glycosylation and had altered phosphorylation following activation by GDNF. The deletion in GDNF prevented secretion of its gene product, reducing RET activation, and the IHH-Q51K variant reduced expression of the transcription factor GLI1. Injection of morpholinos that target ihh reduced the number of enteric neurons to 13% ± 1.4% of control zebrafish. CONCLUSIONS In a study of a large family with history of HSCR, we identified variants in LRBA, RET, the gene encoding the RET ligand (GDNF), IHH, and a gene encoding a mediator of IHH signaling (GLI3). These variants altered functions of the gene products when expressed in cells and knockout of ihh reduced the number of enteric neurons in the zebrafish gut.
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Affiliation(s)
- Yunia Sribudiani
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Biomedical Sciences, Division of Biochemistry and Molecular Biology, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Rajendra K Chauhan
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Maria M Alves
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Lucy Petrova
- Department of Biology, Emory University, Atlanta, Georgia
| | - Erwin Brosens
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Colin Harrison
- Department of Biology, Emory University, Atlanta, Georgia
| | - Tara Wabbersen
- Department of Biology, Emory University, Atlanta, Georgia
| | - Bianca M de Graaf
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Tim Rügenbrink
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Rutger W W Brouwer
- Erasmus Center for Biomics, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Saskia M Maas
- Department of Clinical Genetics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Annelies de Klein
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jan Osinga
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Bart J L Eggen
- Department of Neuroscience, Section Medical Physiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Alan J Burns
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands; Neural Development and Gastroenterology Units, UCL Institute of Child Health, London, UK
| | - Alice S Brooks
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | - Robert M W Hofstra
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands; Neural Development and Gastroenterology Units, UCL Institute of Child Health, London, UK.
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24
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Pollock LM, Xie J, Bell BA, Anand-Apte B. Retinoic acid signaling is essential for maintenance of the blood-retinal barrier. FASEB J 2018; 32:5674-5684. [PMID: 29874129 DOI: 10.1096/fj.201701469r] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The predominant function of the blood-retinal barrier (BRB) is to maintain retinal homeostasis by regulating the influx and efflux between the blood and retina. Breakdown of the BRB occurs in a number of ocular diseases that result in vision loss. Understanding the molecular and cellular pathways involved in the development and maintenance of the BRB is critical to developing therapeutics for these conditions. To visualize the BRB in vivo, we used the transgenic Tg(l-fabp:DBP-EGFP:flk1:mCherry) zebrafish model that expresses vitamin D binding protein (a member of the albumin gene family) tagged to green fluorescent protein. Retinoic acid (RA) plays a number of important roles in vertebrate development and has been shown to play a protective role during inflammation-induced blood-brain barrier disruption. The role of RA in BRB development and maintenance remains unknown. To disrupt RA signaling, Tg(l-fabp:DBP-EGFP:flk1:mCherry) zebrafish were treated with N, N-diethylaminobenzaldehyde and 4-[(1 E)-2-[5,6-dihydro-5,5-dimethyl-8-(2-phenylethynyl)-2-naphthalenyl]ethenyl]benzoic acid, which are antagonists of retinal dehydrogenase and the RA receptor, respectively. Treatment with either compound resulted in BRB disruption and reduced visual acuity, whereas cotreatment with all- trans RA effectively rescued BRB integrity. Additionally, transgenic overexpression of Cyp26a1, which catalyzes RA degradation, resulted in breakdown of the BRB. Our results demonstrate that RA signaling is critical for maintenance of the BRB and could play a role in diseases such as diabetic macular edema.-Pollock, L. M., Xie, J., Bell, B. A., Anand-Apte, B. Retinoic acid signaling is essential for maintenance of the blood-retinal barrier.
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Affiliation(s)
- Lana M Pollock
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Jing Xie
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Brent A Bell
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Bela Anand-Apte
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA.,Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
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25
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Bernstein CS, Anderson MT, Gohel C, Slater K, Gross JM, Agarwala S. The cellular bases of choroid fissure formation and closure. Dev Biol 2018; 440:137-151. [PMID: 29803644 DOI: 10.1016/j.ydbio.2018.05.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 04/30/2018] [Accepted: 05/14/2018] [Indexed: 01/11/2023]
Abstract
Defects in choroid fissure (CF) formation and closure lead to coloboma, a major cause of childhood blindness. Despite genetic advances, the cellular defects underlying coloboma remain poorly elucidated due to our limited understanding of normal CF morphogenesis. We address this deficit by conducting high-resolution spatio-temporal analyses of CF formation and closure in the chick, mouse and fish. We show that a small ventral midline invagination initiates CF formation in the medial-proximal optic cup, subsequently extending it dorsally toward the lens, and proximally into the optic stalk. Unlike previously supposed, the optic disc does not form solely as a result of this invagination. Morphogenetic events that alter the shape of the proximal optic cup also direct clusters of outer layer and optic stalk cells to form dorsal optic disc. A cross-species comparison suggests that CF closure can be accomplished by breaking down basement membranes (BM) along the CF margins, and by establishing BM continuity along the dorsal and ventral surfaces of the CF. CF closure is subsequently accomplished via two distinct mechanisms: tissue fusion or the intercalation of various tissues into the inter-CF space. We identify several novel cell behaviors that underlie CF fusion, many of which involve remodeling of the retinal epithelium. In addition to BM disruption, these include NCAD downregulation along the SOX2+ retinal CF margin, and the protrusion or movement of partially polarized retinal cells into the inter-CF space to mediate fusion. Proximally, the inter-CF space does not fuse or narrow and is instead loosely packed with migrating SOX2+/PAX2+/Vimentin+ astrocytes until it is closed by the outgoing optic nerve. Taken together, our results highlight distinct proximal-distal differences in CF morphogenesis and closure and establish detailed cellular models that can be utilized for understanding the genetic bases of coloboma.
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Affiliation(s)
- Cassidy S Bernstein
- Molecular Biosciences Department, University of Texas at Austin, Austin, TX 78712, USA
| | - Mitchell T Anderson
- Molecular Biosciences Department, University of Texas at Austin, Austin, TX 78712, USA
| | - Chintan Gohel
- Molecular Biosciences Department, University of Texas at Austin, Austin, TX 78712, USA
| | - Kayleigh Slater
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jeffrey M Gross
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Seema Agarwala
- Molecular Biosciences Department, University of Texas at Austin, Austin, TX 78712, USA; Institute for Cell and Molecular Biology, University of Texas at Austin, TX 78712, USA; Institute for Neuroscience, University of Texas at Austin, Austin, TX 78712, USA.
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26
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Hocking JC, Famulski JK, Yoon KH, Widen SA, Bernstein CS, Koch S, Weiss O, Agarwala S, Inbal A, Lehmann OJ, Waskiewicz AJ. Morphogenetic defects underlie Superior Coloboma, a newly identified closure disorder of the dorsal eye. PLoS Genet 2018. [PMID: 29522511 PMCID: PMC5862500 DOI: 10.1371/journal.pgen.1007246] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The eye primordium arises as a lateral outgrowth of the forebrain, with a transient fissure on the inferior side of the optic cup providing an entry point for developing blood vessels. Incomplete closure of the inferior ocular fissure results in coloboma, a disease characterized by gaps in the inferior eye and recognized as a significant cause of pediatric blindness. Here, we identify eight patients with defects in tissues of the superior eye, a congenital disorder that we term superior coloboma. The embryonic origin of superior coloboma could not be explained by conventional models of eye development, leading us to reanalyze morphogenesis of the dorsal eye. Our studies revealed the presence of the superior ocular sulcus (SOS), a transient division of the dorsal eye conserved across fish, chick, and mouse. Exome sequencing of superior coloboma patients identified rare variants in a Bone Morphogenetic Protein (Bmp) receptor (BMPR1A) and T-box transcription factor (TBX2). Consistent with this, we find sulcus closure defects in zebrafish lacking Bmp signaling or Tbx2b. In addition, loss of dorsal ocular Bmp is rescued by concomitant suppression of the ventral-specific Hedgehog pathway, arguing that sulcus closure is dependent on dorsal-ventral eye patterning cues. The superior ocular sulcus acts as a conduit for blood vessels, with altered sulcus closure resulting in inappropriate connections between the hyaloid and superficial vascular systems. Together, our findings explain the existence of superior coloboma, a congenital ocular anomaly resulting from aberrant morphogenesis of a developmental structure. Ocular coloboma is a disease characterized by gaps in the lower portion of the eye and can affect the iris, lens, or retina, and cause loss of vision. Coloboma arises from incomplete closure of a transient fissure on the underside of the developing eye. Therefore, our identification of patients with similar tissue defects, but restricted to the superior half of eye, was surprising. Here, we describe an ocular developmental structure, the superior ocular sulcus, as a potential origin for the congenital disorder superior coloboma. Formation and closure of the sulcus are directed by dorsal-ventral eye patterning, and altered patterning interferes with the role of the sulcus as a pathway for blood vessel growth onto the eye.
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Affiliation(s)
- Jennifer C Hocking
- Division of Anatomy, Department of Surgery, University of Alberta, Edmonton, Canada.,Women & Children's Health Research Institute, University of Alberta, Edmonton, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, Canada
| | - Jakub K Famulski
- Department of Biological Sciences, University of Alberta, Edmonton, Canada.,Department of Biology, University of Kentucky, Lexington, Unites States of America
| | - Kevin H Yoon
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Sonya A Widen
- Women & Children's Health Research Institute, University of Alberta, Edmonton, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Cassidy S Bernstein
- Department of Molecular Biosciences, University of Texas at Austin,Unites States of America
| | - Sophie Koch
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Omri Weiss
- Department of Medical Neurobiology, Institute for Medical Research-Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | | | - Seema Agarwala
- Department of Molecular Biosciences, University of Texas at Austin,Unites States of America.,Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, Unites States of America.,Institute for Neuroscience, University of Texas at Austin, Austin, Unites States of America
| | - Adi Inbal
- Department of Medical Neurobiology, Institute for Medical Research-Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ordan J Lehmann
- Women & Children's Health Research Institute, University of Alberta, Edmonton, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, Canada.,Department of Ophthalmology, University of Alberta, Edmonton, Canada.,Neuroscience and Mental Health Research Institute, University of Alberta, Edmonton, Canada
| | - Andrew J Waskiewicz
- Women & Children's Health Research Institute, University of Alberta, Edmonton, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, Canada.,Neuroscience and Mental Health Research Institute, University of Alberta, Edmonton, Canada
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27
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Gestri G, Bazin-Lopez N, Scholes C, Wilson SW. Cell Behaviors during Closure of the Choroid Fissure in the Developing Eye. Front Cell Neurosci 2018. [PMID: 29515375 PMCID: PMC5826230 DOI: 10.3389/fncel.2018.00042] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Coloboma is a defect in the morphogenesis of the eye that is a consequence of failure of choroid fissure fusion. It is among the most common congenital defects in humans and can significantly impact vision. However, very little is known about the cellular mechanisms that regulate choroid fissure closure. Using high-resolution confocal imaging of the zebrafish optic cup, we find that apico-basal polarity is re-modeled in cells lining the fissure in proximal to distal and inner to outer gradients during fusion. This process is accompanied by cell proliferation, displacement of vasculature, and contact between cells lining the choroid fissure and periocular mesenchyme (POM). To investigate the role of POM cells in closure of the fissure, we transplanted optic vesicles onto the yolk, allowing them to develop in a situation where they are depleted of POM. The choroid fissure forms normally in ectopic eyes but fusion fails in this condition, despite timely apposition of the nasal and temporal lips of the retina. This study resolves some of the cell behaviors underlying choroid fissure fusion and supports a role for POM in choroid fissure fusion.
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Affiliation(s)
- Gaia Gestri
- Division of Biosciences, Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Naiara Bazin-Lopez
- Division of Biosciences, Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Clarissa Scholes
- Division of Biosciences, Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Stephen W Wilson
- Division of Biosciences, Department of Cell and Developmental Biology, University College London, London, United Kingdom
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28
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Merrigan SL, Kennedy BN. Vitamin D receptor agonists regulate ocular developmental angiogenesis and modulate expression of dre-miR-21 and VEGF. Br J Pharmacol 2017; 174:2636-2651. [PMID: 28547797 DOI: 10.1111/bph.13875] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 04/26/2017] [Accepted: 05/15/2017] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND AND PURPOSE Pathological growth of ocular vasculature networks can underpin visual impairment in neovascular age-related macular degeneration, proliferative diabetic retinopathy and retinopathy of prematurity. Our aim was to uncover novel pharmacological regulators of ocular angiogenesis by phenotype-based screening in zebrafish. EXPERIMENTAL APPROACH A bioactive chemical library of 465 drugs was screened to identify small molecule inhibitors of ocular hyaloid vasculature (HV) angiogenesis in zebrafish larvae. Selectivity was assessed by evaluation of non-ocular intersegmental vasculature development. Safety pharmacology examined visual behaviour and retinal histology in larvae. Molecular mechanisms of action were scrutinized using expression profiling of target mRNAs and miRNAs in larval eyes. KEY RESULTS Library screening identified 10 compounds which significantly inhibited HV developmental angiogenesis. The validated hit calcitriol selectively demonstrated dose-dependent attenuation of HV development. In agreement, vitamin D receptor (VDR) agonists paricalcitol, doxercalciferol, maxacalcitol, calcipotriol, seocalcitol, calcifediol and tacalcitol significantly and selectively attenuated HV development. VDR agonists induced minor ocular morphology abnormalities and affected normal visual function. Calcitriol induced a three to sevenfold increase in ocular dre-miR-21 expression. Consistently, all-trans-retinoic acid attenuated HV development and increased ocular dre-miR-21 expression. Interestingly, zebrafish ocular vegfaa and vegfab expression was significantly increased while, vegfc, flt1 and kdrl expression was unchanged by calcitriol. CONCLUSION AND IMPLICATIONS These studies identified VDR agonists as significant and selective anti-angiogenics in the developing vertebrate eye and miR21 as a key downstream regulated miRNA. These targets should be further evaluated as molecular hallmarks of, and therapeutic targets for pathological ocular neovascularization.
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Affiliation(s)
- Stephanie L Merrigan
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
| | - Breandán N Kennedy
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute, University College Dublin, Dublin, Ireland
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29
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Tang X, Gao J, Jia X, Zhao W, Zhang Y, Pan W, He J. Bipotent progenitors as embryonic origin of retinal stem cells. J Cell Biol 2017; 216:1833-1847. [PMID: 28465291 PMCID: PMC5461025 DOI: 10.1083/jcb.201611057] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Revised: 03/01/2017] [Accepted: 04/03/2017] [Indexed: 01/24/2023] Open
Abstract
In lower vertebrates, retinal stem cells (RSCs) capable of producing all retinal cell types are a resource for retinal tissue growth throughout life. However, the embryonic origin of RSCs remains largely elusive. Using a Zebrabow-based clonal analysis, we characterized the RSC niche in the ciliary marginal zone of zebrafish retina and illustrate that blood vessels associated with RSCs are required for the maintenance of actively proliferating RSCs. Full lineage analysis of RSC progenitors reveals lineage patterns of RSC production. Moreover, in vivo lineage analysis demonstrates that these RSC progenitors are the direct descendants of a set of bipotent progenitors in the medial epithelial layer of developing optic vesicles, suggesting the involvement of the mixed-lineage states in the RSC lineage specification.
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Affiliation(s)
- Xia Tang
- State Key Laboratory of Neuroscience, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jianan Gao
- State Key Laboratory of Neuroscience, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Xinling Jia
- State Key Laboratory of Neuroscience, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Wencao Zhao
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai 200031, China
| | - Yijie Zhang
- State Key Laboratory of Neuroscience, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Weijun Pan
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai 200031, China
| | - Jie He
- State Key Laboratory of Neuroscience, Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
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30
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Live imaging of primary ocular vasculature formation in zebrafish. PLoS One 2017; 12:e0176456. [PMID: 28445524 PMCID: PMC5405983 DOI: 10.1371/journal.pone.0176456] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 04/11/2017] [Indexed: 12/31/2022] Open
Abstract
Ocular vasculature consists of the central retinal and ciliary vascular systems, which are essential to maintaining visual function. Many researchers have attempted to determine their origins and development; however, the detailed, stepwise process of ocular vasculature formation has not been established. In zebrafish, two angioblast clusters, the rostral and midbrain organizing centers, form almost all of the cranial vasculature, including the ocular vasculature, and these are from where the cerebral arterial and venous angioblast clusters, respectively, differentiate. In this study, we first determined the anatomical architecture of the primary ocular vasculature and then followed its path from the two cerebral angioblast clusters using a time-lapse analysis of living Tg(flk1:EGFP)k7 zebrafish embryos, in which the endothelial cells specifically expressed enhanced green fluorescent protein. We succeeded in capturing images of the primary ocular vasculature formation and were able to determine the origin of each ocular vessel. In zebrafish, the hyaloid and ciliary arterial systems first organized independently, and then anastomosed via the inner optic circle on the surface of the lens by the lateral transfer of the optic vein. Finally, the choroidal vascular plexus formed around the eyeball to complete the primary ocular vasculature formation. To our knowledge, this study is the first to report successful capture of circular integration of the optic artery and vein, lateral transfer of the optic vein to integrate the hyaloidal and superficial ocular vasculatures, and formation of the choroidal vascular plexus. Furthermore, this new morphological information enables us to assess the entire process of the primary ocular vasculature formation, which will be useful for its precise understanding.
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31
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Blanco-Sánchez B, Clément A, Phillips JB, Westerfield M. Zebrafish models of human eye and inner ear diseases. Methods Cell Biol 2016; 138:415-467. [PMID: 28129854 DOI: 10.1016/bs.mcb.2016.10.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Eye and inner ear diseases are the most common sensory impairments that greatly impact quality of life. Zebrafish have been intensively employed to understand the fundamental mechanisms underlying eye and inner ear development. The zebrafish visual and vestibulo-acoustic systems are very similar to these in humans, and although not yet mature, they are functional by 5days post-fertilization (dpf). In this chapter, we show how the zebrafish has significantly contributed to the field of biomedical research and how researchers, by establishing disease models and meticulously characterizing their phenotypes, have taken the first steps toward therapies. We review here models for (1) eye diseases, (2) ear diseases, and (3) syndromes affecting eye and/or ear. The use of new genome editing technologies and high-throughput screening systems should increase considerably the speed at which knowledge from zebrafish disease models is acquired, opening avenues for better diagnostics, treatments, and therapies.
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Affiliation(s)
| | - A Clément
- University of Oregon, Eugene, OR, United States
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32
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James A, Lee C, Williams AM, Angileri K, Lathrop KL, Gross JM. The hyaloid vasculature facilitates basement membrane breakdown during choroid fissure closure in the zebrafish eye. Dev Biol 2016; 419:262-272. [PMID: 27634568 DOI: 10.1016/j.ydbio.2016.09.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 09/09/2016] [Accepted: 09/09/2016] [Indexed: 12/22/2022]
Abstract
A critical aspect of vertebrate eye development is closure of the choroid fissure (CF). Defects in CF closure result in colobomas, which are a significant cause of childhood blindness worldwide. Despite the growing number of mutated loci associated with colobomas, we have a limited understanding of the cell biological underpinnings of CF closure. Here, we utilize the zebrafish embryo to identify key phases of CF closure and regulators of the process. Utilizing Laminin-111 as a marker for the basement membrane (BM) lining the CF, we determine the spatial and temporal patterns of BM breakdown in the CF, a prerequisite for CF closure. Similarly, utilizing a combination of in vivo time-lapse imaging, β-catenin immunohistochemistry and F-actin staining, we determine that tissue fusion, which serves to close the fissure, follows BM breakdown closely. Periocular mesenchyme (POM)-derived endothelial cells, which migrate through the CF to give rise to the hyaloid vasculature, possess distinct actin foci that correlate with regions of BM breakdown. Disruption of talin1, which encodes a regulator of the actin cytoskeleton, results in colobomas and these correlate with structural defects in the hyaloid vasculature and defects in BM breakdown. cloche mutants, which entirely lack a hyaloid vasculature, also possess defects in BM breakdown in the CF. Taken together, these data support a model in which the hyaloid vasculature and/or the POM-derived endothelial cells that give rise to the hyaloid vasculature contribute to BM breakdown during CF closure.
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Affiliation(s)
- Andrea James
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin TX, 78712
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Chanjae Lee
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin TX, 78712
| | - Andre M Williams
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin TX, 78712
| | - Krista Angileri
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin TX, 78712
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Kira L Lathrop
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
- Department of Bioengineering, University of Pittsburgh Swanson School of Engineering, Pittsburgh, PA 15213
| | - Jeffrey M Gross
- Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin TX, 78712
- Department of Ophthalmology, Louis J. Fox Center for Vision Restoration, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
- Department of Developmental Biology, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
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33
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Rezzola S, Paganini G, Semeraro F, Presta M, Tobia C. Zebrafish ( Danio rerio ) embryo as a platform for the identification of novel angiogenesis inhibitors of retinal vascular diseases. Biochim Biophys Acta Mol Basis Dis 2016; 1862:1291-6. [DOI: 10.1016/j.bbadis.2016.04.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/05/2016] [Accepted: 04/11/2016] [Indexed: 12/26/2022]
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Hanovice NJ, Daly CMS, Gross JM. N-Ethylmaleimide-Sensitive Factor b (nsfb) Is Required for Normal Pigmentation of the Zebrafish Retinal Pigment Epithelium. Invest Ophthalmol Vis Sci 2016; 56:7535-44. [PMID: 26618645 DOI: 10.1167/iovs.15-17704] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
PURPOSE Despite the number of albinism-causing mutations identified in human patients and animal models, there remain a significant number of cases for which no mutation has been identified, suggesting that our understanding of melanogenesis is incomplete. Previously, we identified two oculocutaneous albinism mutations in zebrafish, au13 and au18. Here, we sought to identify the mutated loci and determine how the affected proteins contribute to normal pigmentation of the retinal pigment epithelium (RPE). METHODS Complementation analyses revealed that au13 and au18 belonged to a single complementation group, suggesting that they affected the same locus. Whole-genome sequencing and single nucleotide polymorphism (SNP) analysis was performed to identify putative mutations, which were confirmed by cDNA sequencing and mRNA rescue. Transmission electron microscopy (TEM) and image quantification were used to identify the cellular basis of hypopigmentation. RESULTS Whole-genome sequencing and SNP mapping identified a nonsense mutation in the N-ethylmaleimide-sensitive factor b (nsfb) gene in au18 mutants. Complementary DNA sequencing confirmed the presence of the mutation (C893T), which truncates the nsfb protein by roughly two-thirds (Y297X). No coding sequence mutations were identified in au13, but quantitative PCR revealed a significant decrease in nsfb expression, and nsfb mRNA injection rescued the hypopigmentation phenotype, suggesting a regulatory mutation. In situ hybridization revealed that nsfb is broadly expressed during embryonic development, including in the RPE. Transmission electron microscopy analyses indicated that average melanosome density and maturity were significantly decreased in nsfb mutants. CONCLUSIONS au18 and au13 contain mutations in nsfb, which encodes a protein that is required for the maturation of melanosomes in zebrafish RPE.
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Reynolds AL, Alvarez Y, Sasore T, Waghorne N, Butler CT, Kilty C, Smith AJ, McVicar C, Wong VHY, Galvin O, Merrigan S, Osman J, Grebnev G, Sjölander A, Stitt AW, Kennedy BN. Phenotype-based Discovery of 2-[(E)-2-(Quinolin-2-yl)vinyl]phenol as a Novel Regulator of Ocular Angiogenesis. J Biol Chem 2016; 291:7242-55. [PMID: 26846851 DOI: 10.1074/jbc.m115.710665] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Indexed: 12/21/2022] Open
Abstract
Retinal angiogenesis is tightly regulated to meet oxygenation and nutritional requirements. In diseases such as proliferative diabetic retinopathy and neovascular age-related macular degeneration, uncontrolled angiogenesis can lead to blindness. Our goal is to better understand the molecular processes controlling retinal angiogenesis and discover novel drugs that inhibit retinal neovascularization. Phenotype-based chemical screens were performed using the ChemBridge Diverset(TM)library and inhibition of hyaloid vessel angiogenesis in Tg(fli1:EGFP) zebrafish. 2-[(E)-2-(Quinolin-2-yl)vinyl]phenol, (quininib) robustly inhibits developmental angiogenesis at 4-10 μmin zebrafish and significantly inhibits angiogenic tubule formation in HMEC-1 cells, angiogenic sprouting in aortic ring explants, and retinal revascularization in oxygen-induced retinopathy mice. Quininib is well tolerated in zebrafish, human cell lines, and murine eyes. Profiling screens of 153 angiogenic and inflammatory targets revealed that quininib does not directly target VEGF receptors but antagonizes cysteinyl leukotriene receptors 1 and 2 (CysLT1-2) at micromolar IC50values. In summary, quininib is a novel anti-angiogenic small-molecule CysLT receptor antagonist. Quininib inhibits angiogenesis in a range of cell and tissue systems, revealing novel physiological roles for CysLT signaling. Quininib has potential as a novel therapeutic agent to treat ocular neovascular pathologies and may complement current anti-VEGF biological agents.
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Affiliation(s)
- Alison L Reynolds
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Yolanda Alvarez
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Temitope Sasore
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Nora Waghorne
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Clare T Butler
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Claire Kilty
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Andrew J Smith
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Carmel McVicar
- the Centre for Experimental Medicine, Queen's University Belfast, Wellcome-Wolfson Building, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom, and
| | - Vickie H Y Wong
- the Centre for Experimental Medicine, Queen's University Belfast, Wellcome-Wolfson Building, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom, and
| | - Orla Galvin
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Stephanie Merrigan
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Janina Osman
- the Division of Cell and Experimental Pathology, Department of Translational Medicine, Lund University, Skåne University Hospital, 20502 Malmö, Sweden
| | - Gleb Grebnev
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland
| | - Anita Sjölander
- the Division of Cell and Experimental Pathology, Department of Translational Medicine, Lund University, Skåne University Hospital, 20502 Malmö, Sweden
| | - Alan W Stitt
- the Centre for Experimental Medicine, Queen's University Belfast, Wellcome-Wolfson Building, 97 Lisburn Road, Belfast, BT9 7BL, United Kingdom, and
| | - Breandán N Kennedy
- From the University College Dublin School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Ireland,
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Dhakal S, Stevens CB, Sebbagh M, Weiss O, Frey RA, Adamson S, Shelden EA, Inbal A, Stenkamp DL. Abnormal retinal development in Cloche mutant zebrafish. Dev Dyn 2015; 244:1439-1455. [PMID: 26283463 DOI: 10.1002/dvdy.24322] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 08/04/2015] [Accepted: 08/09/2015] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Functions for the early embryonic vasculature in regulating development of central nervous system tissues, such as the retina, have been suggested by in vitro studies and by in vivo manipulations that caused additional ocular vessels to develop. Here, we use an avascular zebrafish embryo, cloche-/- (clo-/-), to begin to identify necessary developmental functions of the ocular vasculature in regulating development and patterning of the neural retina, in vivo. These studies are possible in zebrafish embryos, which do not yet rely upon the vasculature for tissue oxygenation. RESULTS clo-/- embryos lacked early ocular vasculature and were microphthalmic, with reduced retinal cell proliferation and cell survival. Retinas of clo mutants were disorganized, with irregular synaptic layers, mispatterned expression domains of retinal transcription factors, morphologically abnormal Müller glia, reduced differentiation of specific retinal cell types, and sporadically distributed cone photoreceptors. Blockade of p53-mediated cell death did not completely rescue this phenotype and revealed ectopic cones in the inner nuclear layer. clo-/- embryos did not upregulate a molecular marker for hypoxia. CONCLUSIONS The disorganized retinal phenotype of clo-/- embryos is consistent with a neural and glial developmental patterning role for the early ocular vasculature that is independent of its eventual function in gas exchange.
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Affiliation(s)
- Susov Dhakal
- Department of Biological Sciences, University of Idaho, Moscow, ID USA.,Neuroscience Graduate Program, University of Idaho, Moscow, ID USA
| | - Craig B Stevens
- Department of Biological Sciences, University of Idaho, Moscow, ID USA
| | - Meyrav Sebbagh
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Omri Weiss
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Ruth A Frey
- Department of Biological Sciences, University of Idaho, Moscow, ID USA
| | - Seth Adamson
- Department of Biological Sciences, University of Idaho, Moscow, ID USA
| | - Eric A Shelden
- Department of Molecular Biosciences, Washington State University, Pullman, WA USA
| | - Adi Inbal
- Department of Medical Neurobiology, Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel
| | - Deborah L Stenkamp
- Department of Biological Sciences, University of Idaho, Moscow, ID USA.,Neuroscience Graduate Program, University of Idaho, Moscow, ID USA
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Hypoxia-induced retinal neovascularization in zebrafish embryos: a potential model of retinopathy of prematurity. PLoS One 2015; 10:e0126750. [PMID: 25978439 PMCID: PMC4433197 DOI: 10.1371/journal.pone.0126750] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 04/07/2015] [Indexed: 01/09/2023] Open
Abstract
Retinopathy of prematurity, formerly known as a retrolental fibroplasia, is a leading cause of infantile blindness worldwide. Retinopathy of prematurity is caused by the failure of central retinal vessels to reach the retinal periphery, creating a nonperfused peripheral retina, resulting in retinal hypoxia, neovascularization, vitreous hemorrhage, vitreoretinal fibrosis, and loss of vision. We established a potential retinopathy of prematurity model by using a green fluorescent vascular endothelium zebrafish transgenic line treated with cobalt chloride (a hypoxia-inducing agent), followed by GS4012 (a vascular endothelial growth factor inducer) at 24 hours postfertilization, and observed that the number of vascular branches and sprouts significantly increased in the central retinal vascular trunks 2-4 days after treatment. We created an angiography method by using tetramethylrhodamine dextran, which exhibited severe vascular leakage through the vessel wall into the surrounding retinal tissues. The quantification of mRNA extracted from the heads of the larvae by using real-time quantitative polymerase chain reaction revealed a twofold increase in vegfaa and vegfr2 expression compared with the control group, indicating increased vascular endothelial growth factor signaling in the hypoxic condition. In addition, we demonstrated that the hypoxic insult could be effectively rescued by several antivascular endothelial growth factor agents such as SU5416, bevacizumab, and ranibizumab. In conclusion, we provide a simple, highly reproducible, and clinically relevant retinopathy of prematurity model based on zebrafish embryos; this model may serve as a useful platform for clarifying the mechanisms of human retinopathy of prematurity and its progression.
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Kaufman R, Weiss O, Sebbagh M, Ravid R, Gibbs-Bar L, Yaniv K, Inbal A. Development and origins of zebrafish ocular vasculature. BMC DEVELOPMENTAL BIOLOGY 2015; 15:18. [PMID: 25888280 PMCID: PMC4406013 DOI: 10.1186/s12861-015-0066-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/28/2015] [Indexed: 01/26/2023]
Abstract
Background The developing eye receives blood supply from two vascular systems, the intraocular hyaloid system and the superficial choroidal vessels. In zebrafish, a highly stereotypic and simple set of vessels develops on the surface of the eye prior to development of choroidal vessels. The origins and formation of this so-called superficial system have not been described. Results We have analyzed the development of superficial vessels by time-lapse imaging and identified their origins by photoconversion experiments in kdrl:Kaede transgenic embryos. We show that the entire superficial system is derived from a venous origin, and surprisingly, we find that the hyaloid system has, in addition to its previously described arterial origin, a venous origin for specific vessels. Despite arising solely from a vein, one of the vessels in the superficial system, the nasal radial vessel (NRV), appears to acquire an arterial identity while growing over the nasal aspect of the eye and this happens in a blood flow-independent manner. Conclusions Our results provide a thorough analysis of the early development and origins of zebrafish ocular vessels and establish the superficial vasculature as a model for studying vascular patterning in the context of the developing eye. Electronic supplementary material The online version of this article (doi:10.1186/s12861-015-0066-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Rivka Kaufman
- Department of Medical Neurobiology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.
| | - Omri Weiss
- Department of Medical Neurobiology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.
| | - Meyrav Sebbagh
- Department of Medical Neurobiology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.
| | - Revital Ravid
- Department of Medical Neurobiology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.
| | - Liron Gibbs-Bar
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
| | - Karina Yaniv
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
| | - Adi Inbal
- Department of Medical Neurobiology, Institute for Medical Research - Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem, Israel. .,Department of Medical Neurobiology, Hebrew University Medical School, Ein-Kerem, Jerusalem, 9112002, Israel.
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