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Zhang X, Leavey P, Appel H, Makrides N, Blackshaw S. Molecular mechanisms controlling vertebrate retinal patterning, neurogenesis, and cell fate specification. Trends Genet 2023; 39:736-757. [PMID: 37423870 PMCID: PMC10529299 DOI: 10.1016/j.tig.2023.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 07/11/2023]
Abstract
This review covers recent advances in understanding the molecular mechanisms controlling neurogenesis and specification of the developing retina, with a focus on insights obtained from comparative single cell multiomic analysis. We discuss recent advances in understanding the mechanisms by which extrinsic factors trigger transcriptional changes that spatially pattern the optic cup (OC) and control the initiation and progression of retinal neurogenesis. We also discuss progress in unraveling the core evolutionarily conserved gene regulatory networks (GRNs) that specify early- and late-state retinal progenitor cells (RPCs) and neurogenic progenitors and that control the final steps in determining cell identity. Finally, we discuss findings that provide insight into regulation of species-specific aspects of retinal patterning and neurogenesis, including consideration of key outstanding questions in the field.
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Affiliation(s)
- Xin Zhang
- Department of Ophthalmology, Columbia University School of Medicine, New York, NY, USA; Department of Pathology and Cell Biology, Columbia University School of Medicine, New York, NY, USA.
| | - Patrick Leavey
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Haley Appel
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Neoklis Makrides
- Department of Ophthalmology, Columbia University School of Medicine, New York, NY, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Psychiatry and Behavioral Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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2
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Bise T, Pfefferli C, Bonvin M, Taylor L, Lischer HEL, Bruggmann R, Jaźwińska A. The regeneration-responsive element careg monitors activation of Müller glia after MNU-induced damage of photoreceptors in the zebrafish retina. Front Mol Neurosci 2023; 16:1160707. [PMID: 37138703 PMCID: PMC10149768 DOI: 10.3389/fnmol.2023.1160707] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/27/2023] [Indexed: 05/05/2023] Open
Abstract
In contrast to mammals, zebrafish can regenerate their damaged photoreceptors. This capacity depends on the intrinsic plasticity of Müller glia (MG). Here, we identified that the transgenic reporter careg, a marker of regenerating fin and heart, also participates in retina restoration in zebrafish. After methylnitrosourea (MNU) treatment, the retina became deteriorated and contained damaged cell types including rods, UV-sensitive cones and the outer plexiform layer. This phenotype was associated with the induction of careg expression in a subset of MG until the reconstruction of the photoreceptor synaptic layer. Single-cell RNA sequencing (scRNAseq) analysis of regenerating retinas revealed a population of immature rods, defined by high expression of rhodopsin and the ciliogenesis gene meig1, but low expression of phototransduction genes. Furthermore, cones displayed deregulation of metabolic and visual perception genes in response to retina injury. Comparison between careg:EGFP expressing and non-expressing MG demonstrated that these two subpopulations are characterized by distinct molecular signatures, suggesting their heterogenous responsiveness to the regenerative program. Dynamics of ribosomal protein S6 phosphorylation showed that TOR signaling became progressively switched from MG to progenitors. Inhibition of TOR with rapamycin reduced the cell cycle activity, but neither affected careg:EGFP expression in MG, nor prevented restoration of the retina structure. This indicates that MG reprogramming, and progenitor cell proliferation might be regulated by distinct mechanisms. In conclusion, the careg reporter detects activated MG, and provides a common marker of regeneration-competent cells in diverse zebrafish organs, including the retina.
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Affiliation(s)
- Thomas Bise
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | | | - Marylène Bonvin
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Lea Taylor
- Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Heidi E. L. Lischer
- Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Rémy Bruggmann
- Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Anna Jaźwińska
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- *Correspondence: Anna Jaźwińska,
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3
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Sun G, Li Y. Molecular mechanisms of developmental toxicity induced by BBP in zebrafish embryos. Toxicology 2021; 466:153078. [PMID: 34933018 DOI: 10.1016/j.tox.2021.153078] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/30/2021] [Accepted: 12/16/2021] [Indexed: 02/07/2023]
Abstract
Butylbenzyl phthalate (BBP) has been shown to negatively affect the development of zebrafish embryos, however, its underlying mechanisms remain unclear. Therefore, our study aims to reveal the molecular mechanisms of developmental toxicity on zebrafish embryos. Zebrafish embryos were exposed to BBP (0, 0.6, and 1.2 mg/L) from 4 to 72 h post-fertilization (hpf). The adverse effects on zebrafish embryos were evaluated and the transcriptional profiles of zebrafish embryos were analyzed at 72hpf. Exposure to BBP decreased hatching and survival rates and induced obvious morphology abnormalities in zebrafish embryos. The activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) significantly decrease and the malondialdehyde (MDA) content significantly increased with 1.2 mg/L BBP exposure. Global transcriptome profiling analysis demonstrated that 578 and 1257 genes were differentially expressed in zebrafish embryos in the 0.6 and 1.2 mg/L groups, respectively. Gene Ontology (GO) term enrichment analysis demonstrated that DEGs are related to many aspects of cell composition, biological processes, and molecular functions. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis demonstrated that 13 and 22 pathways were significantly enriched in the 0.6 and 1.2 mg/L groups, respectively. DEGs were primarily concentrated in the metabolism of the 0.6 mg/L group and in the organismal systems and particularly affected vision and digestion in the 1.2 mg/L group. Our results contribute to a better understanding of the underlying mechanisms of developmental toxicity induced by phthalates.
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Affiliation(s)
- Guijin Sun
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
| | - Yingqiu Li
- School of Food Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China
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Valencia JE, Feuda R, Mellott DO, Burke RD, Peter IS. Ciliary photoreceptors in sea urchin larvae indicate pan-deuterostome cell type conservation. BMC Biol 2021; 19:257. [PMID: 34863182 PMCID: PMC8642985 DOI: 10.1186/s12915-021-01194-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 11/12/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The evolutionary history of cell types provides insights into how morphological and functional complexity arose during animal evolution. Photoreceptor cell types are particularly broadly distributed throughout Bilateria; however, their evolutionary relationship is so far unresolved. Previous studies indicate that ciliary photoreceptors are homologous at least within chordates, and here, we present evidence that a related form of this cell type is also present in echinoderm larvae. RESULTS Larvae of the purple sea urchin Strongylocentrotus purpuratus have photoreceptors that are positioned bilaterally in the oral/anterior apical neurogenic ectoderm. Here, we show that these photoreceptors express the transcription factor Rx, which is commonly expressed in ciliary photoreceptors, together with an atypical opsin of the GO family, opsin3.2, which localizes in particular to the cilia on the cell surface of photoreceptors. We show that these ciliary photoreceptors express the neuronal marker synaptotagmin and are located in proximity to pigment cells. Furthermore, we systematically identified additional transcription factors expressed in these larval photoreceptors and found that a majority are orthologous to transcription factors expressed in vertebrate ciliary photoreceptors, including Otx, Six3, Tbx2/3, and Rx. Based on the developmental expression of rx, these photoreceptors derive from the anterior apical neurogenic ectoderm. However, genes typically involved in eye development in bilateria, including pax6, six1/2, eya, and dac, are not expressed in sea urchin larval photoreceptors but are instead co-expressed in the hydropore canal. CONCLUSIONS Based on transcription factor expression, location, and developmental origin, we conclude that the sea urchin larval photoreceptors constitute a cell type that is likely homologous to the ciliary photoreceptors present in chordates.
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Affiliation(s)
- Jonathan E Valencia
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
| | - Roberto Feuda
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.,Present address: Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Dan O Mellott
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada
| | - Robert D Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia, Canada.
| | - Isabelle S Peter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
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Shiau F, Ruzycki PA, Clark BS. A single-cell guide to retinal development: Cell fate decisions of multipotent retinal progenitors in scRNA-seq. Dev Biol 2021; 478:41-58. [PMID: 34146533 PMCID: PMC8386138 DOI: 10.1016/j.ydbio.2021.06.005] [Citation(s) in RCA: 6] [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: 02/13/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 12/20/2022]
Abstract
Recent advances in high throughput single-cell RNA sequencing (scRNA-seq) technology have enabled the simultaneous transcriptomic profiling of thousands of individual cells in a single experiment. To investigate the intrinsic process of retinal development, researchers have leveraged this technology to quantify gene expression in retinal cells across development, in multiple species, and from numerous important models of human disease. In this review, we summarize recent applications of scRNA-seq and discuss how these datasets have complemented and advanced our understanding of retinal progenitor cell competence, cell fate specification, and differentiation. Finally, we also highlight the outstanding questions in the field that advances in single-cell data generation and analysis will soon be able to answer.
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Affiliation(s)
- Fion Shiau
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Philip A Ruzycki
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Brian S Clark
- John F Hardesty, MD Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
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Yu P, Wang Y, Yang WT, Li Z, Zhang XJ, Zhou L, Gui JF. Upregulation of the PPAR signaling pathway and accumulation of lipids are related to the morphological and structural transformation of the dragon-eye goldfish eye. SCIENCE CHINA-LIFE SCIENCES 2021; 64:1031-1049. [PMID: 33428077 DOI: 10.1007/s11427-020-1814-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 08/19/2020] [Indexed: 02/07/2023]
Abstract
Goldfish comprise around 300 different strains with drastically altered and aesthetical morphologies making them suitable models for evolutionary developmental biology. The dragon-eye strain is characterized by protruding eyes (analogous to those of Chinese dragons). Although the strain has been selected for about 400 years, the mechanism of its eye development remains unclear. In this study, a stable dragon-eye goldfish strain with a clear genetic background was rapidly established and studied. We found that upregulation of the PPAR signaling pathway accompanied by an increase in lipid accumulation might trigger the morphological and structural transformation of the eye in dragon-eye goldfish. At the developmental stage of proptosis (eye protrusion), downregulation of the phototransduction pathway was consistent with the structural defects and myopia of the dragon-eye strain. With the impairment of retinal development, cytokine-induced inflammation was activated, especially after proptosis, similar to the pathologic symptoms of many human ocular diseases. In addition, differentially expressed transcription factors were significantly enriched in the PAX and homeobox families, two well-known transcription factor families involved in eye development. Therefore, our findings reveal the dynamic changes in key pathways during eye development in dragon-eye goldfish, and provide insights into the molecular mechanisms underlying drastically altered eyes in goldfish and human ocular disease.
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Affiliation(s)
- Peng Yu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yang Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wen-Tao Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Zhi Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Xiao-Juan Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China
| | - Li Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jian-Fang Gui
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, the Innovative Academy of Seed Design, Chinese Academy of Sciences, Wuhan, 430072, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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7
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Thyroid hormone receptors mediate two distinct mechanisms of long-wavelength vision. Proc Natl Acad Sci U S A 2020; 117:15262-15269. [PMID: 32541022 DOI: 10.1073/pnas.1920086117] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Thyroid hormone (TH) signaling plays an important role in the regulation of long-wavelength vision in vertebrates. In the retina, thyroid hormone receptor β (thrb) is required for expression of long-wavelength-sensitive opsin (lws) in red cone photoreceptors, while in retinal pigment epithelium (RPE), TH regulates expression of a cytochrome P450 enzyme, cyp27c1, that converts vitamin A1 into vitamin A2 to produce a red-shifted chromophore. To better understand how TH controls these processes, we analyzed the phenotype of zebrafish with mutations in the three known TH nuclear receptor transcription factors (thraa, thrab, and thrb). We found that no single TH nuclear receptor is required for TH-mediated induction of cyp27c1 but that deletion of all three (thraa -/- ;thrab -/- ;thrb -/- ) completely abrogates its induction and the resulting conversion of A1- to A2-based retinoids. In the retina, loss of thrb resulted in an absence of red cones at both larval and adult stages without disruption of the underlying cone mosaic. RNA-sequencing analysis revealed significant down-regulation of only five genes in adult thrb -/- retina, of which three (lws1, lws2, and miR-726) occur in a single syntenic cluster. In the thrb -/- retina, retinal progenitors destined to become red cones were transfated into ultraviolet (UV) cones and horizontal cells. Taken together, our findings demonstrate cooperative regulation of cyp27c1 by TH receptors and a requirement for thrb in red cone fate determination. Thus, TH signaling coordinately regulates both spectral sensitivity and sensory plasticity.
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8
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Abstract
Vertebrate color vision requires spectrally selective opsin-based pigments, expressed in distinct cone photoreceptor populations. In primates and in fish, spectrally divergent opsin genes may reside in head-to-tail tandem arrays. Mechanisms underlying differential expression from such arrays have not been fully elucidated. Regulation of human red (LWS) vs. green (MWS) opsins is considered a stochastic event, whereby upstream enhancers associate randomly with promoters of the proximal or distal gene, and one of these associations becomes permanent. We demonstrate that, distinct from this stochastic model, the endocrine signal thyroid hormone (TH) regulates differential expression of the orthologous zebrafish lws1/lws2 array, and of the tandemly quadruplicated rh2-1/rh2-2/rh2-3/rh2-4 array. TH treatment caused dramatic, dose-dependent increases in abundance of lws1, the proximal member of the lws array, and reduced lws2 Fluorescent lws reporters permitted direct visualization of individual cones switching expression from lws2 to lws1 Athyroidism increased lws2 and reduced lws1, except within a small ventral domain of lws1 that was likely sustained by retinoic acid signaling. Changes in lws abundance and distribution in athyroid zebrafish were rescued by TH, demonstrating plasticity of cone phenotype in response to this signal. TH manipulations also regulated the rh2 array, with athyroidism reducing abundance of distal members. Interestingly, the opsins encoded by the proximal lws gene and distal rh2 genes are sensitive to longer wavelengths than other members of their respective arrays; therefore, endogenous TH acts upon each opsin array to shift overall spectral sensitivity toward longer wavelengths, underlying coordinated changes in visual system function during development and growth.
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9
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DuVal MG, Allison WT. Photoreceptor Progenitors Depend Upon Coordination of gdf6a, thrβ, and tbx2b to Generate Precise Populations of Cone Photoreceptor Subtypes. Invest Ophthalmol Vis Sci 2019; 59:6089-6101. [PMID: 30592497 DOI: 10.1167/iovs.18-24461] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Replacing cone photoreceptors, the units of the retina necessary for daytime vision, depends upon the successful production of a full variety of new cones from, for example, stem cells. Using genetic experiments in a model organism with high cone diversity, zebrafish, we map the intersecting effects of cone development factors gdf6a, tbx2b, and thrβ. Methods We investigated these genes of interest by using genetic combinations of mutants, gene knockdown, and dominant negative gene expression, and then quantified cone subtype outcomes (which normally develop in tightly regulated ratios). Results Gdf6a mutants have reduced blue cones and, discovered here, reduced red cones. In combined gdf6a/tbx2b disruption, the loss of gdf6a in heterozygous tbx2b mutants reduced UV cones. Intriguingly, when we disrupted thrβ in gdf6a mutants by using a thrβ morpholino, their combined early disruption revealed a lamination phenotype. Disrupting thrβ activity via expression of a dominant negative thrβ (dnthrβ) at either early or late retinal development had differential outcomes on red cones (reduced abundance), versus UV and blue cones (increased abundance). By using dnthrβ in gdf6a mutants, we revealed that disrupting thrβ activity did not change gdf6a mutant cone phenotypes. Conclusions Gdf6a loss directly affects blue and red cones and indirectly affects UV cones by increasing sensitivity to additional disruption, such as reduced tbx2b, resulting in fewer UV cones. The effects of thrβ change through photoreceptor development, first promoting red cones and restricting UV cones, and later restricting UV and blue cones. The effects of gdf6a on UV, blue, and red cone development overlap with, but likely supersede, those of thrβ.
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Affiliation(s)
- Michèle G DuVal
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - W Ted Allison
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
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10
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Xie S, Han S, Qu Z, Liu F, Li J, Yu S, Reilly J, Tu J, Liu X, Lu Z, Hu X, Yimer TA, Qin Y, Huang Y, Lv Y, Jiang T, Shu X, Tang Z, Jia H, Wong F, Liu M. Knockout of Nr2e3 prevents rod photoreceptor differentiation and leads to selective L-/M-cone photoreceptor degeneration in zebrafish. Biochim Biophys Acta Mol Basis Dis 2019; 1865:1273-1283. [PMID: 30684641 DOI: 10.1016/j.bbadis.2019.01.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 01/20/2019] [Accepted: 01/21/2019] [Indexed: 01/28/2023]
Abstract
Mutations in the photoreceptor cell-specific nuclear receptor gene Nr2e3 increased the number of S-cone photoreceptors in human and murine retinas and led to retinal degeneration that involved photoreceptor and non-photoreceptor cells. The mechanisms underlying these complex phenotypes remain unclear. In the hope of understanding the precise role of Nr2e3 in photoreceptor cell fate determination and differentiation, we generated a line of Nr2e3 knockout zebrafish using CRISPR technology. In these Nr2e3-null animals, rod precursors undergo terminal mitoses but fail to differentiate as rods. Rod-specific genes are not expressed and the outer segment (OS) fails to form. Formation and differentiation of cone photoreceptors is normal. Specifically, there is no increase in the number of UV-cone or S-cone photoreceptors. Laminated retinal structure is maintained. After normal development, L-/M-cones selectively degenerate, with progressive shortening of OS that starts at age 1 month. The amount of cone phototransduction proteins is concomitantly reduced, whereas UV- and S-cones have normal OS lengths even at age 10 months. In vitro studies show Nr2e3 synergizes with Crx and Nrl to enhance rhodopsin gene expression. Nr2e3 does not affect cone opsin expression. Our results extend the knowledge of Nr2e3's roles and have specific implications for the interpretation of the phenotypes observed in human and murine retinas. Furthermore, our model may offer new opportunities in finding treatments for enhanced S-cone syndrome (ESCS) and other retinal degenerative diseases.
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Affiliation(s)
- Shanglun Xie
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Shanshan Han
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Zhen Qu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Fei Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Jingzhen Li
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Shanshan Yu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - James Reilly
- Department of Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, Scotland, United Kingdom of Great Britain and Northern Ireland
| | - Jiayi Tu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Xiliang Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Zhaojing Lu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Xuebin Hu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Tinsae Assefa Yimer
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Yayun Qin
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Yuwen Huang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Yuexia Lv
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Tao Jiang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Xinhua Shu
- Department of Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, Scotland, United Kingdom of Great Britain and Northern Ireland
| | - Zhaohui Tang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Haibo Jia
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
| | - Fulton Wong
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Mugen Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
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Zelinka CP, Sotolongo-Lopez M, Fadool JM. Targeted disruption of the endogenous zebrafish rhodopsin locus as models of rapid rod photoreceptor degeneration. Mol Vis 2018; 24:587-602. [PMID: 30210230 PMCID: PMC6128699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Accepted: 08/24/2018] [Indexed: 12/05/2022] Open
Abstract
Purpose Retinitis pigmentosa (RP) is a collection of genetic disorders that results in the degeneration of light-sensitive photoreceptor cells, leading to blindness. RP is associated with more than 70 loci that may display dominant or recessive modes of inheritance, but mutations in the gene encoding the visual pigment rhodopsin (RHO) are the most frequent cause. In an effort to develop precise mutations in zebrafish as novel models of photoreceptor degeneration, we describe the generation and germline transmission of a series of novel clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-induced insertion and deletion (indel) mutations in the major zebrafish rho locus, rh1-1. Methods One- or two-cell staged zebrafish embryos were microinjected with in vitro transcribed mRNA encoding Cas9 and a single guide RNA (gRNA). Mutations were detected by restriction fragment length polymorphism (RFLP) and DNA sequence analyses in injected embryos and offspring. Immunolabeling with rod- and cone-specific antibodies was used to test for histological and cellular changes. Results Using gRNAs that targeted highly conserved regions of rh1-1, a series of dominant and recessive alleles were recovered that resulted in the rapid degeneration of rod photoreceptors. No effect on cones was observed. Targeting the 5'-coding sequence of rh1-1 led to the recovery of several indels similar to disease-associated alleles. A frame shift mutation leading to a premature stop codon (T17*) resulted in rod degeneration when brought to homozygosity. Immunoblot and fluorescence labeling with a Rho-specific antibody suggest that this is indeed a null allele, illustrating that the Rho expression is essential for rod survival. Two in-frame mutations were recovered that disrupted the highly conserved N-linked glycosylation consensus sequence at N15. Larvae heterozygous for either of the alleles demonstrated rapid rod degeneration. Targeting of the 3'-coding region of rh1-1 resulted in the recovery of an allele encoding a premature stop codon (S347*) upstream of the conserved VSPA sorting sequence and a second in-frame allele that disrupted the putative phosphorylation site at S339. Both alleles resulted in rod death in a dominant inheritance pattern. Following the loss of the targeting sequence, immunolabeling for Rho was no longer restricted to the rod outer segment, but it was also localized to the plasma membrane. Conclusions The efficiency of CRISPR/Cas9 for gene targeting, coupled with the large number of mutations associated with RP, provided a backdrop for the rapid isolation of novel alleles in zebrafish that phenocopy disease. These novel lines will provide much needed in-vivo models for high throughput screens of compounds or genes that protect from photoreceptor degeneration.
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Affiliation(s)
- Christopher P. Zelinka
- Department of Biological Science, Florida State University, Tallahassee, FL
- Program in Neuroscience, Florida State University, Tallahassee, FL
| | | | - James M. Fadool
- Department of Biological Science, Florida State University, Tallahassee, FL
- Program in Neuroscience, Florida State University, Tallahassee, FL
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12
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Sun C, Galicia C, Stenkamp DL. Transcripts within rod photoreceptors of the Zebrafish retina. BMC Genomics 2018; 19:127. [PMID: 29422031 PMCID: PMC5806438 DOI: 10.1186/s12864-018-4499-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 01/28/2018] [Indexed: 12/03/2022] Open
Abstract
Background The purpose of this study was to identify transcripts of retinal rod photoreceptors of the zebrafish. The zebrafish is an important animal model for vision science due to rapid and tractable development, persistent neurogenesis of rods throughout the lifespan, and capacity for functional retinal regeneration. Results Zebrafish rods, and non-rod retinal cells of the xops:eGFP transgenic line, were separated by cell dissociation and fluorescence-activated cell sorting (FACS), followed by RNA-seq. At a false discovery rate of < 0.01, 597 transcripts were upregulated (“enriched”) in rods vs. other retinal cells, and 1032 were downregulated (“depleted”). Thirteen thousand three hundred twenty four total transcripts were detected in rods, including many not previously known to be expressed by rods. Forty five transcripts were validated by qPCR in FACS-sorted rods vs. other retinal cells. Transcripts enriched in rods from adult retinas were also enriched in rods from larval and juvenile retinas, and were also enriched in rods sorted from retinas subjected to a neurotoxic lesion and allowed to regenerate. Many transcripts enriched in rods were upregulated in retinas of wildtype retinas vs. those of a zebrafish model for rod degeneration. Conclusions We report the generation and validation of an RNA-seq dataset describing the rod transcriptome of the zebrafish, which is now available as a resource for further studies of rod photoreceptor biology and comparative transcriptomics. Electronic supplementary material The online version of this article (10.1186/s12864-018-4499-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chi Sun
- Department of Biological Sciences, University of Idaho, 875 Perimeter Drive, MS 3051, Moscow, ID, 83844-3051, USA
| | - Carlos Galicia
- Department of Biological Sciences, University of Idaho, 875 Perimeter Drive, MS 3051, Moscow, ID, 83844-3051, USA
| | - Deborah L Stenkamp
- Department of Biological Sciences, University of Idaho, 875 Perimeter Drive, MS 3051, Moscow, ID, 83844-3051, USA.
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13
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Zhu B, Ge W. Genome editing in fishes and their applications. Gen Comp Endocrinol 2018; 257:3-12. [PMID: 28919449 DOI: 10.1016/j.ygcen.2017.09.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 08/15/2017] [Accepted: 09/13/2017] [Indexed: 12/18/2022]
Abstract
There have been revolutionary progresses in genome engineering in the past few years. The newly-emerged genome editing technologies including zinc-finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN) and clustered regularly interspaced short palindromic repeats associated with Cas9 (CRISPR/Cas9) have enabled biological scientists to perform efficient and precise targeted genome editing in different species. Fish represent the largest group of vertebrates with many species having values for both scientific research and aquaculture industry. Genome editing technologies have found extensive applications in different fish species for basic functional studies as well asapplied research in such fields as disease modeling and aquaculture. This mini-review focuses on recent advancements and applications of the new generation of genome editing technologies in fish species, with particular emphasis on their applications in understanding reproductive functions because the reproductive axis has been most systematically and best studied among others and its function has been difficult to address with reverse genetics approach.
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Affiliation(s)
- Bo Zhu
- Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Wei Ge
- Centre of Reproduction, Development and Aging, Faculty of Health Sciences, University of Macau, Taipa, Macau, China.
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14
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Kuniyoshi N, Yoshida Y, Itoh Y, Yokota SI, Kuraishi T, Hattori S, Kondo T, Yoshizawa M, Kai C, Kiso Y, Kusakabe KT. Morphological analyses of the retinal photoreceptor cells in the nocturnally adapted owl monkeys. J Vet Med Sci 2018; 80:413-420. [PMID: 29375079 PMCID: PMC5880819 DOI: 10.1292/jvms.17-0418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Owl monkeys are the only one species possessing the nocturnal lifestyles among the simian monkeys. Their eyes and retinas have been interested associating with the nocturnal adaptation. We examined the cellular
specificity and electroretinogram (ERG) reactivity in the retina of the owl monkeys by comparison with the squirrel monkeys, taxonomically close-species and expressing diurnal behavior. Owl monkeys did not have clear
structure of the foveal pit by the funduscope, whereas the retinal wholemount specimens indicated a small-condensed spot of the ganglion cells. There were abundant numbers of the rod photoreceptor cells in owl monkeys
than those of the squirrel monkeys. However, the owl monkeys’ retina did not possess superiority for rod cell-reactivity in the scotopic ERG responses. Scanning electron microscopic observation revealed that the rod
cells in owl monkeys’ retina had very small-sized inner and outer segments as compared with squirrel monkeys. Owl monkeys showed typical nocturnal traits such as rod-cell dominance. However, the individual photoreceptor
cells seemed to be functionally weak for visual capacity, caused from the morphological immaturity at the inner and outer segments.
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Affiliation(s)
- Nobue Kuniyoshi
- Laboratory of Basic Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Yuji Yoshida
- Laboratory of Veterinary Anatomy, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Yoshiki Itoh
- Laboratory of Veterinary Radiology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Shin-Ichi Yokota
- Amami Laboratory of Injurious Animals, Institute of Medical Science, The University of Tokyo, Kagoshima 894-1531, Japan
| | - Takeshi Kuraishi
- Amami Laboratory of Injurious Animals, Institute of Medical Science, The University of Tokyo, Kagoshima 894-1531, Japan.,Present affiliation: HAMURI Co., Ltd., Ibaraki 306-0101, Japan
| | - Shosaku Hattori
- Amami Laboratory of Injurious Animals, Institute of Medical Science, The University of Tokyo, Kagoshima 894-1531, Japan
| | - Tomohiro Kondo
- Laboratory of Laboratory Animal Science, Division of Veterinary Science, Graduate School of Life and Environmental Science, Osaka Prefecture University, Osaka 598-8531, Japan
| | - Midori Yoshizawa
- Graduate School of Agricultural Science, Utsunomiya University, Tochigi 321-8505, Japan
| | - Chieko Kai
- Amami Laboratory of Injurious Animals, Institute of Medical Science, The University of Tokyo, Kagoshima 894-1531, Japan
| | - Yasuo Kiso
- Laboratory of Basic Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515, Japan.,Laboratory of Veterinary Anatomy, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
| | - Ken Takeshi Kusakabe
- Laboratory of Basic Veterinary Science, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515, Japan.,Laboratory of Veterinary Anatomy, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi 753-8515, Japan
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15
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Zhang J, Liu L, Ren L, Feng W, Lv P, Wu W, Yan Y. The single and joint toxicity effects of chlorpyrifos and beta-cypermethrin in zebrafish (Danio rerio) early life stages. JOURNAL OF HAZARDOUS MATERIALS 2017; 334:121-131. [PMID: 28407539 DOI: 10.1016/j.jhazmat.2017.03.055] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 03/14/2017] [Accepted: 03/24/2017] [Indexed: 05/28/2023]
Abstract
Water environment pollution caused by the widespread application of beta-cypermethrin (BCP) and chlorpyrifos (CPF) in agriculture has attracted extensive concern of the world. In this study, zebrafish was used as a model to investigate the individual and joint toxicity of BCP and CPF. In the acute toxicity test, 3 hpf embryos were exposed to various concentrations of CPF, BCP and their binary mixtures (MIX) for 96h. The results indicated that these two pesticides and mixtures induced malformation and death in larvae, and affected hatchability. These two pesticides in mixtures were verified to act together in a synergistic manner under experimental conditions. Oxidative stress assaying manifested that CPF, BCP and MIX altered CAT, SOD and GST activities and MDA content, resulting in oxidative damage in larvae. By pathology analysis, CPF (236μg/L), BCP (5.9μg/L) and MIX (236μg/L CPF+5.9μg/L BCP) were found to trigger liver lesions and promote apoptosis in tissues. The transcriptome sequencing suggested that ECM- receptor interaction, focal adhesion, cell cycle, DNA replication, phototransduction and adherens junction pathways were closely associated with the toxicity of these two pesticides.
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Affiliation(s)
- Jiayu Zhang
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Lili Liu
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Lei Ren
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Weimin Feng
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Peng Lv
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wei Wu
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yanchun Yan
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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16
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Cell Type-Specific Epigenomic Analysis Reveals a Uniquely Closed Chromatin Architecture in Mouse Rod Photoreceptors. Sci Rep 2017; 7:43184. [PMID: 28256534 PMCID: PMC5335693 DOI: 10.1038/srep43184] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 01/19/2017] [Indexed: 12/24/2022] Open
Abstract
Rod photoreceptors are specialized neurons that mediate vision in dim light and are the predominant photoreceptor type in nocturnal mammals. The rods of nocturnal mammals are unique among vertebrate cell types in having an ‘inverted’ nuclear architecture, with a dense mass of heterochromatin in the center of the nucleus rather than dispersed clumps at the periphery. To test if this unique nuclear architecture is correlated with a unique epigenomic landscape, we performed ATAC-seq on mouse rods and their most closely related cell type, cone photoreceptors. We find that thousands of loci are selectively closed in rods relative to cones as well as >60 additional cell types. Furthermore, we find that the open chromatin profile of photoreceptors lacking the rod master regulator Nrl is nearly indistinguishable from that of native cones, indicating that Nrl is required for selective chromatin closure in rods. Finally, we identified distinct enrichments of transcription factor binding sites in rods and cones, revealing key differences in the cis-regulatory grammar of these cell types. Taken together, these data provide insight into the development and maintenance of photoreceptor identity, and highlight rods as an attractive system for studying the relationship between nuclear organization and local changes in gene regulation.
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17
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Brockerhoff SE. Genome Editing to Study Ca 2+ Homeostasis in Zebrafish Cone Photoreceptors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1016:91-100. [PMID: 29130155 DOI: 10.1007/978-3-319-63904-8_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Photoreceptors are specialized sensory neurons with unique biological features. Phototransduction is well understood due in part to the exclusive expression and function of the molecular components of this cascade. Many other processes are less well understood, but also extremely important for understanding photoreceptor function and for treating disease. One example is the role of Ca2+ in the cell body and overall compartmentalization and regulation of Ca2+ within the cell. The recent development of CRISPR/Cas9 genome editing techniques has made it possible to rapidly and cheaply alter specific genes. This will help to define the biological function of elusive processes that have been more challenging to study. CRISPR/Cas9 has been optimized in many systems including zebrafish, which already has some distinct advantages for studying photoreceptor biology and function. These new genome editing technologies and the continued use of the zebrafish model system will help advance our understanding of important understudied aspects of photoreceptor biology.
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Affiliation(s)
- Susan E Brockerhoff
- Departments of Biochemistry and Ophthalmology, University of Washington, UW Medicine, 750 Republican St, Box 358058, Seattle, WA, 98109, USA.
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18
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Valen R, Eilertsen M, Edvardsen RB, Furmanek T, Rønnestad I, van der Meeren T, Karlsen Ø, Nilsen TO, Helvik JV. The two-step development of a duplex retina involves distinct events of cone and rod neurogenesis and differentiation. Dev Biol 2016; 416:389-401. [PMID: 27374844 DOI: 10.1016/j.ydbio.2016.06.041] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 06/23/2016] [Accepted: 06/27/2016] [Indexed: 11/15/2022]
Abstract
Unlike in mammals, persistent postembryonic retinal growth is a characteristic feature of fish, which includes major remodeling events that affect all cell types including photoreceptors. Consequently, visual capabilities change during development, where retinal sensitivity to different wavelengths of light (photopic vision), -and to limited photons (scotopic vision) are central capabilities for survival. Differently from well-established model fish, Atlantic cod has a prolonged larval stage where only cone photoreceptors are present. Rods do not appear until juvenile transition (metamorphosis), a hallmark of indirect developing species. Previously we showed that whole gene families of lws (red-sensitive) and sws1 (UV-sensitive) opsins have been lost in cod, while rh2a (green-sensitive) and sws2 (blue-sensitive) genes have tandem duplicated. Here, we provide a comprehensive characterization of a two-step developing duplex retina in Atlantic cod. The study focuses on cone subtype dynamics and delayed rod neurogenesis and differentiation in all cod life stages. Using transcriptomic and histological approaches we show that different opsins disappear in a topographic manner during development where central to peripheral retina is a key axis of expressional change. Early cone differentiation was initiated in dorso-temporal retina different from previously described in fish. Rods first appeared during initiation of metamorphosis and expression of the nuclear receptor transcription factor nr2e3-1, suggest involvement in rod specification. The indirect developmental strategy thus allows for separate studies of cones and rods development, which in nature correlates with visual changes linked to habitat shifts. The clustering of key retinal genes according to life stage, suggests that Atlantic cod with its sequenced genome may be an important resource for identification of underlying factors required for development and function of photopic and scotopic vision.
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Affiliation(s)
- Ragnhild Valen
- Department of Biology, University of Bergen, NO-5020 Bergen, Norway
| | | | | | - Tomasz Furmanek
- Institute of Marine Research, Nordnes, NO-5005 Bergen, Norway
| | - Ivar Rønnestad
- Department of Biology, University of Bergen, NO-5020 Bergen, Norway
| | - Terje van der Meeren
- Institute of Marine Research, Austevoll Research station and Hjort Centre for Marine Ecosystem Dynamics, NO-5392 Storebø, Norway
| | - Ørjan Karlsen
- Institute of Marine Research, Austevoll Research station and Hjort Centre for Marine Ecosystem Dynamics, NO-5392 Storebø, Norway
| | | | - Jon Vidar Helvik
- Department of Biology, University of Bergen, NO-5020 Bergen, Norway
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