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Retinal Stem Cell 'Retirement Plans': Growth, Regulation and Species Adaptations in the Retinal Ciliary Marginal Zone. Int J Mol Sci 2021; 22:ijms22126528. [PMID: 34207050 PMCID: PMC8234741 DOI: 10.3390/ijms22126528] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 12/12/2022] Open
Abstract
The vertebrate retina develops from a specified group of precursor cells that adopt distinct identities and generate lineages of either the neural retina, retinal pigmented epithelium, or ciliary body. In some species, including teleost fish and amphibians, proliferative cells with stem-cell-like properties capable of continuously supplying new retinal cells post-embryonically have been characterized and extensively studied. This region, termed the ciliary or circumferential marginal zone (CMZ), possibly represents a conserved retinal stem cell niche. In this review, we highlight the research characterizing similar CMZ-like regions, or stem-like cells located at the peripheral margin, across multiple different species. We discuss the proliferative parameters, multipotency and growth mechanisms of these cells to understand how they behave in vivo and how different molecular factors and signalling networks converge at the CMZ niche to regulate their activity. The evidence suggests that the mature retina may have a conserved propensity for homeostatic growth and plasticity and that dysfunction in the regulation of CMZ activity may partially account for dystrophic eye growth diseases such as myopia and hyperopia. A better understanding of the properties of CMZ cells will enable important insight into how an endogenous generative tissue compartment can adapt to altered retinal physiology and potentially even restore vision loss caused by retinal degenerative conditions.
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2
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Xu B, Tang X, Jin M, Zhang H, Du L, Yu S, He J. Unifying developmental programs for embryonic and postembryonic neurogenesis in the zebrafish retina. Development 2020; 147:dev.185660. [PMID: 32467236 DOI: 10.1242/dev.185660] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 05/13/2020] [Indexed: 01/14/2023]
Abstract
The zebrafish retina grows for a lifetime. Whether embryonic and postembryonic retinogenesis conform to the same developmental program is an outstanding question that remains under debate. Using single-cell RNA sequencing of ∼20,000 cells of the developing zebrafish retina at four different stages, we identified seven distinct developmental states. Each state explicitly expresses a gene set. Disruption of individual state-specific marker genes results in various defects ranging from small eyes to the loss of distinct retinal cell types. Using a similar approach, we further characterized the developmental states of postembryonic retinal stem cells (RSCs) and their progeny in the ciliary marginal zone. Expression pattern analysis of state-specific marker genes showed that the developmental states of postembryonic RSCs largely recapitulated those of their embryonic counterparts, except for some differences in rod photoreceptor genesis. Thus, our findings reveal the unifying developmental program used by the embryonic and postembryonic retinogenesis in zebrafish.
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Affiliation(s)
- Baijie Xu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
| | - Xia Tang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China .,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
| | - Mengmeng Jin
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
| | - Hui Zhang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
| | - Lei Du
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
| | - Shuguang Yu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
| | - Jie He
- Institute of Neuroscience, State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China .,Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology, Shanghai 201210, China
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3
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Li G, Jin D, Zhong TP. Tubgcp3 Is Required for Retinal Progenitor Cell Proliferation During Zebrafish Development. Front Mol Neurosci 2019; 12:126. [PMID: 31178691 PMCID: PMC6543929 DOI: 10.3389/fnmol.2019.00126] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Accepted: 04/29/2019] [Indexed: 11/13/2022] Open
Abstract
The centrosomal protein γ-tubulin complex protein 3 (Tubgcp3/GCP3) is required for the assembly of γ-tubulin small complexes (γ-TuSCs) and γ-tubulin ring complexes (γ-TuRCs), which play critical roles in mitotic spindle formation during mitosis. However, its function in vertebrate embryonic development is unknown. Here, we generated the zebrafish tubgcp3 mutants using the CRISPR/Cas9 system and found that the tubgcp3 mutants exhibited the small eye phenotype. Tubgcp3 is required for the cell cycle progression of retinal progenitor cells (RPCs), and its depletion caused cell cycle arrest in the mitotic (M) phase. The M-phase arrested RPCs exhibited aberrant monopolar spindles and abnormal distributed centrioles and γ-tubulin. Moreover, these RPCs underwent apoptosis finally. Our study provides the in vivo model for the functional study of Tubgcp3 and sheds light on the roles of centrosomal γ-tubulin complexes in vertebrate development.
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Affiliation(s)
- Guobao Li
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Regulatory Biology, Institute of Molecular Medicine, School of Life Sciences, East China Normal University, Shanghai, China
| | - Daqing Jin
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Regulatory Biology, Institute of Molecular Medicine, School of Life Sciences, East China Normal University, Shanghai, China
| | - Tao P Zhong
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Zhongshan Hospital, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Regulatory Biology, Institute of Molecular Medicine, School of Life Sciences, East China Normal University, Shanghai, China
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4
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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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5
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Sun J, Tang S, Peng H, Saunders DMV, Doering JA, Hecker M, Jones PD, Giesy JP, Wiseman S. Combined Transcriptomic and Proteomic Approach to Identify Toxicity Pathways in Early Life Stages of Japanese Medaka (Oryzias latipes) Exposed to 1,2,5,6-Tetrabromocyclooctane (TBCO). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:7781-90. [PMID: 27322799 DOI: 10.1021/acs.est.6b01249] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Currently, the novel brominated flame retardant 1,2,5,6-tetrabromocyclooctane (TBCO) is considered a potential replacement for hexabromocyclododecane (HBCD). Therefore, use of TBCO could increase in the near future. To assess potential toxicological risks to aquatic organisms, embryos of Japanese medaka (Oryzias latipes) were exposed to 10, 100, or 1000 μg/L TBCO from 2 h postfertilization until 1 day post-hatch. TBCO accumulated in embryos in the order of 0.43-1.3 × 10(4)-fold, and the rate constant of accumulation was 1.7-1.8 per day. The number of days to hatch and the hatching success of embryos exposed to the medium and the greatest concentrations of TBCO were impaired. Responses of the transcriptome (RNA-seq) and proteome were characterized in embryos exposed to 100 μg/L TBCO because this was the least concentration of TBCO that caused an effect on hatching. Consistent with effects on hatching, proteins whose abundances were reduced by exposure to TBCO were enriched in embryo development and hatching pathways. Also, on the basis of the responses of transcriptome and proteome, it was predicted that TBCO might impair vision and contraction of cardiac muscle, respectively, and these effects were confirmed by targeted bioassays. This study provided a comprehensive understanding of effects of TBCO on medaka at early life stages and illustrated the power of "omics" to explain and predict phenotypic responses to chemicals.
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Affiliation(s)
- Jianxian Sun
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
| | - Song Tang
- School of Environment and Sustainability, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5C8, Canada
| | - Hui Peng
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
| | - David M V Saunders
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
| | - Jon A Doering
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
| | - Markus Hecker
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
- School of Environment and Sustainability, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5C8, Canada
| | - Paul D Jones
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
- School of Environment and Sustainability, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5C8, Canada
| | - John P Giesy
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
- Department of Veterinary Biomedical Sciences, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B4, Canada
- Zoology Department, Center for Integrative Toxicology, Michigan State University , East Lansing, Michigan 48824, United States
- School of Biological Sciences, University of Hong Kong , Hong Kong Special Administrative Region 999077, People's Republic of China
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210093, People's Republic of China
| | - Steve Wiseman
- Toxicology Centre, University of Saskatchewan , Saskatoon, Saskatchewan S7N 5B3, Canada
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6
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Valdivia LE, Lamb DB, Horner W, Wierzbicki C, Tafessu A, Williams AM, Gestri G, Krasnow AM, Vleeshouwer-Neumann TS, Givens M, Young RM, Lawrence LM, Stickney HL, Hawkins TA, Schwarz QP, Cavodeassi F, Wilson SW, Cerveny KL. Antagonism between Gdf6a and retinoic acid pathways controls timing of retinal neurogenesis and growth of the eye in zebrafish. Development 2016; 143:1087-98. [PMID: 26893342 PMCID: PMC4852494 DOI: 10.1242/dev.130922] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 02/08/2016] [Indexed: 12/27/2022]
Abstract
Maintaining neurogenesis in growing tissues requires a tight balance between progenitor cell proliferation and differentiation. In the zebrafish retina, neuronal differentiation proceeds in two stages with embryonic retinal progenitor cells (RPCs) of the central retina accounting for the first rounds of differentiation, and stem cells from the ciliary marginal zone (CMZ) being responsible for late neurogenesis and growth of the eye. In this study, we analyse two mutants with small eyes that display defects during both early and late phases of retinal neurogenesis. These mutants carry lesions in gdf6a, a gene encoding a BMP family member previously implicated in dorsoventral patterning of the eye. We show that gdf6a mutant eyes exhibit expanded retinoic acid (RA) signalling and demonstrate that exogenous activation of this pathway in wild-type eyes inhibits retinal growth, generating small eyes with a reduced CMZ and fewer proliferating progenitors, similar to gdf6a mutants. We provide evidence that RA regulates the timing of RPC differentiation by promoting cell cycle exit. Furthermore, reducing RA signalling in gdf6a mutants re-establishes appropriate timing of embryonic retinal neurogenesis and restores putative stem and progenitor cell populations in the CMZ. Together, our results support a model in which dorsally expressed gdf6a limits RA pathway activity to control the transition from proliferation to differentiation in the growing eye. Summary: In the vertebrate eye, dorsally expressed Gdf6a limits RA pathway activity to control the transition from proliferation to differentiation, thereby regulating eye size.
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Affiliation(s)
- Leonardo E Valdivia
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Dayna B Lamb
- Department of Biology, Reed College, 3203 SE Woodstock Boulevard, Portland, OR 97202, USA
| | - Wilson Horner
- Department of Biology, Reed College, 3203 SE Woodstock Boulevard, Portland, OR 97202, USA
| | - Claudia Wierzbicki
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Amanuel Tafessu
- Department of Biology, Reed College, 3203 SE Woodstock Boulevard, Portland, OR 97202, USA
| | - Audrey M Williams
- Department of Biology, Reed College, 3203 SE Woodstock Boulevard, Portland, OR 97202, USA
| | - Gaia Gestri
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Anna M Krasnow
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | | | - McKenzie Givens
- Department of Biology, Reed College, 3203 SE Woodstock Boulevard, Portland, OR 97202, USA
| | - Rodrigo M Young
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Lisa M Lawrence
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Heather L Stickney
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Thomas A Hawkins
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Quenten P Schwarz
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Florencia Cavodeassi
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Stephen W Wilson
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK
| | - Kara L Cerveny
- Department of Cell and Developmental Biology, UCL, Gower Street, London WC1E 6BT, UK Department of Biology, Reed College, 3203 SE Woodstock Boulevard, Portland, OR 97202, USA
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7
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Gonzalez-Nunez V. Role of gabra2, GABA A receptor alpha-2 subunit, in CNS development. Biochem Biophys Rep 2015; 3:190-201. [PMID: 29124181 PMCID: PMC5668850 DOI: 10.1016/j.bbrep.2015.08.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 07/30/2015] [Accepted: 08/05/2015] [Indexed: 12/02/2022] Open
Abstract
gabra2 gene codes for the alpha-2 subunit of the GABAA receptor, one of the ionotropic receptors which has been related to anxiety, depression and other behavioural disorders, including drug dependence and schizophrenia. GABAergic signalling also plays a role during development, by promoting neural stem cell maintenance and renewal. To investigate the role of gabra2 in CNS development, gabra2 deficient zebrafish were generated. The pattern of proliferation during the embryonic development was disrupted in morphant embryos, which also displayed an increase in the number of apoptotic nuclei mainly at the mid- and hindbrain regions. The expression of several genes (notch1, pax2, fgf8 and wnt1) known to contribute to the development of the central nervous system was also affected in gabra2 morpholino-injected embryos, although no changes were found for pax6a and shh a expression. The transcriptional activity of neuroD (a proneural gene involved in early neuronal determination) was down-regulated in gabra2 deficient embryos, and the expression pattern of gad1b (GABA-synthesising enzyme GAD67) was clearly reduced in injected fish. I propose that gabra2 might be interacting with those signalling pathways that regulate proliferation, differentiation and neurogenesis during the embryonic development; thus, gabra2 might be playing a role in the differentiation of the mesencephalon and cerebellum. Given that changes in GABAergic circuits during development have been related to several psychiatric disorders, such as autism and schizophrenia, this work might be helpful to understand the role of neurotransmitter systems during CNS development and to assess the developmental effects of several GABAergic drugs. gabra2 might have a role in the regulation of proliferation during CNS development. The expression of notch1, pax2a, fgf8 and wnt1 is altered in gabra2 deficient fish. neuro D expression, is down-regulated in the absence of a functional Gabra2. The generation of GABAergic neurons might be reduced in gabra2 morphants. gabra2 may interact with several signalling pathways that harness CNS development.
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Key Words
- CNS, central nervous system
- Central nervous system
- Development
- Differentiation
- GABA
- GABA, γ-aminobutyric acid
- GABAA, gamma-aminobutyric acid (GABA) A receptor
- Gabra2
- ISH, in situ hybridisation
- KCC2, neuron-specific potassium/chloride cotransporter 2
- MHB, mid-hindbrain boundary
- ORF, open reading frame
- Proliferation
- fgf8, fibroblast growth factor 8
- gabra2, gamma-aminobutyric acid receptor subunit alpha-2
- gad1b, glutamate decarboxylase
- hpf, hours post-fertilisation
- neuroD, neurogenic differentiation
- notch1a, notch homologue 1a
- pax2a, paired box gene 2a
- pax6a, paired box gene 2a
- shh a, sonic hedgehog
- wnt1, wingless-type MMTV integration site family, member 1
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Affiliation(s)
- Veronica Gonzalez-Nunez
- Department of Biochemistry and Molecular Biology, University of Salamanca, Spain.,Faculty of Medicine, Instituto de Neurociencias de Castilla y León (INCyL), University of Salamanca, Spain.,Institute of Biomedical Research of Salamanca (IBSAL), Spain
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8
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Li WH, Zhou L, Li Z, Wang Y, Shi JT, Yang YJ, Gui JF. Zebrafish Lbh-like Is Required for Otx2-mediated Photoreceptor Differentiation. Int J Biol Sci 2015; 11:688-700. [PMID: 25999792 PMCID: PMC4440259 DOI: 10.7150/ijbs.11244] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Accepted: 04/11/2015] [Indexed: 12/12/2022] Open
Abstract
The homeobox transcription factor orthodenticle homolog 2 (otx2) is supposed as an organizer that orchestrates a transcription factor network during photoreceptor development. However, its regulation in the process remains unclear. In this study, we have identified a zebrafish limb bud and heart-like gene (lbh-like), which is expressed initially at 30 hours post fertilization (hpf) in the developing brain and eyes. Lbh-like knockdown by morpholinos specifically inhibits expression of multiple photoreceptor-specific genes, such as opsins, gnat1, gnat2 and irbp. Interestingly, otx2 expression in the morphants is not significantly reduced until 32 hpf when lbh-like begins to express, but its expression level in 72 hpf morphants is higher than that in wild type embryos. Co-injection of otx2 and its downstream target neuroD mRNAs can rescue the faults in eyes of Lbh-like morphants. Combined with the results of promoter-reporter assay, we suggest that lbh-like is a new regulator of photoreceptor differentiation directly through affecting otx2 expression in zebrafish. Furthermore, knockdown of lbh-like increases the activity of Notch pathway and perturbs the balance among proliferation, differentiation and survival of photoreceptor precursors.
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Affiliation(s)
- Wen-Hua Li
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, ; 2. Graduate University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Li Zhou
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences
| | - Zhi Li
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences
| | - Yang Wang
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences
| | - Jian-Tao Shi
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences
| | - Yan-Jing Yang
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, ; 2. Graduate University of the Chinese Academy of Sciences, Wuhan 430072, China
| | - Jian-Fang Gui
- 1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences
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9
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Lenkowski JR, Raymond PA. Müller glia: Stem cells for generation and regeneration of retinal neurons in teleost fish. Prog Retin Eye Res 2014; 40:94-123. [PMID: 24412518 DOI: 10.1016/j.preteyeres.2013.12.007] [Citation(s) in RCA: 223] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 12/28/2013] [Accepted: 12/30/2013] [Indexed: 12/31/2022]
Abstract
Adult zebrafish generate new neurons in the brain and retina throughout life. Growth-related neurogenesis allows a vigorous regenerative response to damage, and fish can regenerate retinal neurons, including photoreceptors, and restore functional vision following photic, chemical, or mechanical destruction of the retina. Müller glial cells in fish function as radial-glial-like neural stem cells. During adult growth, Müller glial nuclei undergo sporadic, asymmetric, self-renewing mitotic divisions in the inner nuclear layer to generate a rod progenitor that migrates along the radial fiber of the Müller glia into the outer nuclear layer, proliferates, and differentiates exclusively into rod photoreceptors. When retinal neurons are destroyed, Müller glia in the immediate vicinity of the damage partially and transiently dedifferentiate, re-express retinal progenitor and stem cell markers, re-enter the cell cycle, undergo interkinetic nuclear migration (characteristic of neuroepithelial cells), and divide once in an asymmetric, self-renewing division to generate a retinal progenitor. This daughter cell proliferates rapidly to form a compact neurogenic cluster surrounding the Müller glia; these multipotent retinal progenitors then migrate along the radial fiber to the appropriate lamina to replace missing retinal neurons. Some aspects of the injury-response in fish Müller glia resemble gliosis as observed in mammals, and mammalian Müller glia exhibit some neurogenic properties, indicative of a latent ability to regenerate retinal neurons. Understanding the specific properties of fish Müller glia that facilitate their robust capacity to generate retinal neurons will inform and inspire new clinical approaches for treating blindness and visual loss with regenerative medicine.
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Affiliation(s)
- Jenny R Lenkowski
- Department of Molecular, Cellular, and Developmental Biology, College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, MI, USA.
| | - Pamela A Raymond
- Department of Molecular, Cellular, and Developmental Biology, College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, MI, USA.
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10
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Iglesias AI, Springelkamp H, van der Linde H, Severijnen LA, Amin N, Oostra B, Kockx CEM, van den Hout MCGN, van IJcken WFJ, Hofman A, Uitterlinden AG, Verdijk RM, Klaver CCW, Willemsen R, van Duijn CM. Exome sequencing and functional analyses suggest that SIX6 is a gene involved in an altered proliferation–differentiation balance early in life and optic nerve degeneration at old age. Hum Mol Genet 2013; 23:1320-32. [DOI: 10.1093/hmg/ddt522] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
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11
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Gonzalez-Nunez V, Jimenez González A, Barreto-Valer K, Rodríguez RE. In vivo regulation of the μ opioid receptor: role of the endogenous opioid agents. Mol Med 2013; 19:7-17. [PMID: 23348513 DOI: 10.2119/molmed.2012.00318] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 01/15/2013] [Indexed: 01/07/2023] Open
Abstract
It is well known that genotypic differences can account for the subject-specific responses to opiate administration. In this regard, the basal activity of the endogenous system (either at the receptor or ligand level) can modulate the effects of exogenous agonists as morphine and vice versa. The μ opioid receptor from zebrafish, dre-oprm1, binds endogenous peptides and morphine with similar affinities. Morphine administration during development altered the expression of the endogenous opioid propeptides proenkephalins and proopiomelanocortin. Treatment with opioid peptides (Met-enkephalin [Met-ENK], Met-enkephalin-Gly-Tyr [MEGY] and β-endorphin [β-END]) modulated dre-oprm1 expression during development. Knocking down the dre-oprm1 gene significantly modified the mRNA expression of the penk and pomc genes, thus indicating that oprm1 is involved in shaping penk and pomc expression. In addition, the absence of a functional oprm1 clearly disrupted the embryonic development, since proliferation was disorganized in the central nervous system of oprm1-morphant embryos: mitotic cells were found widespread through the optic tectum and were not restricted to the proliferative areas of the mid- and hindbrain. Transferase-mediated dUTP nick-end labeling (TUNEL) staining revealed that the number of apoptotic cells in the central nervous system (CNS) of morphants was clearly increased at 24-h postfertilization. These findings clarify the role of the endogenous opioid system in CNS development. Our results will also help unravel the complex feedback loops that modulate opioid activity and that may be involved in establishing a coordinated expression of both receptors and endogenous ligands. Further knowledge of the complex interactions between the opioid system and analgesic drugs will provide insights that may be relevant for analgesic therapy.
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Affiliation(s)
- Veronica Gonzalez-Nunez
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, Instituto de Neurociencias de Castilla y León, University of Salamanca, Salamanca, Spain.
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Cerveny KL, Varga M, Wilson SW. Continued growth and circuit building in the anamniote visual system. Dev Neurobiol 2012; 72:328-45. [PMID: 21563317 DOI: 10.1002/dneu.20917] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Fish and amphibia are capable of lifelong growth and regeneration. The two core components of their visual system, the retina and tectum both maintain small populations of stem cells that contribute new neurons and glia to these tissues as they grow. As the animals age, the initial retinal projections onto the tectum are continuously remodeled to maintain retinotopy. These properties raise several biological challenges related to the control of proliferation and differentiation of retinal and tectal stem cells. For instance, how do stem and progenitor cells integrate intrinsic and extrinsic cues to produce the appropriate type and number of cells needed by the growing tissue. Does retinal growth or neuronal activity influence tectal growth? What are the cellular and molecular mechanisms that enable retinal axons to shift their tectal connections as these two tissues grow in incongruent patterns? While we cannot yet provide answers to these questions, this review attempts to supply background and context, laying the ground work for new investigations.
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Affiliation(s)
- Kara L Cerveny
- Department of Cell and Developmental Biology, University College, London, UK
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Bibliowicz J, Tittle RK, Gross JM. Toward a better understanding of human eye disease insights from the zebrafish, Danio rerio. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 100:287-330. [PMID: 21377629 DOI: 10.1016/b978-0-12-384878-9.00007-8] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Visual impairment and blindness is widespread across the human population, and the development of therapies for ocular pathologies is of high priority. The zebrafish represents a valuable model organism for studying human ocular disease; it is utilized in eye research to understand underlying developmental processes, to identify potential causative genes for human disorders, and to develop therapies. Zebrafish eyes are similar in morphology, physiology, gene expression, and function to human eyes. Furthermore, zebrafish are highly amenable to laboratory research. This review outlines the use of zebrafish as a model for human ocular diseases such as colobomas, glaucoma, cataracts, photoreceptor degeneration, as well as dystrophies of the cornea and retinal pigmented epithelium.
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Affiliation(s)
- Jonathan Bibliowicz
- University of Texas at Austin, Section of Molecular Cell and Developmental Biology, Austin, Texas, USA
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