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Huang M, Chow CH, Gurdita A, Harada H, Pham Truong VQB, Eide S, Sun HS, Feng ZP, Monnier PP, Wallace VA, Sugita S. SNAP-25, but not SNAP-23, is essential for photoreceptor development, survival, and function in mice. Commun Biol 2024; 7:34. [PMID: 38182732 PMCID: PMC10770054 DOI: 10.1038/s42003-023-05760-8] [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: 09/18/2023] [Accepted: 12/29/2023] [Indexed: 01/07/2024] Open
Abstract
SNARE-mediated vesicular transport is thought to play roles in photoreceptor glutamate exocytosis and photopigment delivery. However, the functions of Synaptosomal-associated protein (SNAP) isoforms in photoreceptors are unknown. Here, we revisit the expression of SNAP-23 and SNAP-25 and generate photoreceptor-specific knockout mice to investigate their roles. Although we find that SNAP-23 shows weak mRNA expression in photoreceptors, SNAP-23 removal does not affect retinal morphology or vision. SNAP-25 mRNA is developmentally regulated and undergoes mRNA trafficking to photoreceptor inner segments at postnatal day 9 (P9). SNAP-25 knockout photoreceptors develop normally until P9 but degenerate by P14 resulting in severe retinal thinning. Photoreceptor loss in SNAP-25 knockout mice is associated with abolished electroretinograms and vision loss. We find mistrafficked photopigments, enlarged synaptic vesicles, and abnormal synaptic ribbons which potentially underlie photoreceptor degeneration. Our results conclude that SNAP-25, but not SNAP-23, mediates photopigment delivery and synaptic functioning required for photoreceptor development, survival, and function.
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Affiliation(s)
- Mengjia Huang
- Division of Experimental & Translational Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Chun Hin Chow
- Division of Experimental & Translational Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Akshay Gurdita
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
- Donald K. Johnson Eye Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
| | - Hidekiyo Harada
- Donald K. Johnson Eye Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
| | - Victor Q B Pham Truong
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
- Donald K. Johnson Eye Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
| | - Sarah Eide
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Hong-Shuo Sun
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
- Department of Anatomy, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Zhong-Ping Feng
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Philippe P Monnier
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
- Donald K. Johnson Eye Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
- Department of Ophthalmology & Vision Sciences, University of Toronto, Toronto, ON, M5T 3A9, Canada
| | - Valerie A Wallace
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, M5S 1A8, Canada
- Donald K. Johnson Eye Institute, University Health Network, Toronto, ON, M5T 0S8, Canada
- Department of Ophthalmology & Vision Sciences, University of Toronto, Toronto, ON, M5T 3A9, Canada
| | - Shuzo Sugita
- Division of Experimental & Translational Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ON, M5T 0S8, Canada.
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada.
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2
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Gurdita A, Pham Truong VQB, Dolati P, Juric M, Tachibana N, Liu ZC, Ortín-Martínez A, Ibrahimi M, Pokrajac NT, Comanita L, Pacal M, Huang M, Sugita S, Bremner R, Wallace VA. Progenitor division and cell autonomous neurosecretion are required for rod photoreceptor sublaminar positioning. Proc Natl Acad Sci U S A 2023; 120:e2308204120. [PMID: 37812728 PMCID: PMC10589646 DOI: 10.1073/pnas.2308204120] [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: 06/13/2023] [Accepted: 09/06/2023] [Indexed: 10/11/2023] Open
Abstract
Migration is essential for the laminar stratification and connectivity of neurons in the central nervous system. In the retina, photoreceptors (PRs) migrate to positions according to birthdate, with early-born cells localizing to the basal-most side of the outer nuclear layer. It was proposed that apical progenitor mitoses physically drive these basal translocations non-cell autonomously, but direct evidence is lacking, and whether other mechanisms participate is unknown. Here, combining loss- or gain-of-function assays to manipulate cell cycle regulators (Sonic hedgehog, Cdkn1a/p21) with an in vivo lentiviral labelling strategy, we demonstrate that progenitor division is one of two forces driving basal translocation of rod soma. Indeed, replacing Shh activity rescues abnormal rod translocation in retinal explants. Unexpectedly, we show that rod differentiation also promotes rod soma translocation. While outer segment function or formation is dispensable, Crx and SNARE-dependent synaptic function are essential. Thus, both non-cell and cell autonomous mechanisms underpin PR soma sublaminar positioning in the mammalian retina.
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Affiliation(s)
- Akshay Gurdita
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Victor Q. B. Pham Truong
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Parnian Dolati
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Matey Juric
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Nobuhiko Tachibana
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Zhongda C. Liu
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Arturo Ortín-Martínez
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Mostafa Ibrahimi
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Nenad T. Pokrajac
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Lacrimioara Comanita
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
| | - Marek Pacal
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ONM5G 1X5, Canada
| | - Mengjia Huang
- Division of Experimental and Translational Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ONM5T 2S8, Canada
- Department of Physiology, University of Toronto, Toronto, ONM5S 1A8, Canada
| | - Shuzo Sugita
- Division of Experimental and Translational Neuroscience, Krembil Brain Institute, University Health Network, Toronto, ONM5T 2S8, Canada
- Department of Physiology, University of Toronto, Toronto, ONM5S 1A8, Canada
| | - Rod Bremner
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ONM5G 1X5, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ONM5T 3A9, Canada
| | - Valerie A. Wallace
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ONM5S 1A8, Canada
- Donald K. Johnson Eye Institute, Krembil Research Institute, University Health Network, Toronto, ONM5T 2S8, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ONM5T 3A9, Canada
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3
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Occelli LM, Tran NM, Chen S, Petersen-Jones SM. Cat LCA-CRX Model, Homozygous for an Antimorphic Mutation Has a Unique Phenotype. Transl Vis Sci Technol 2023; 12:15. [PMID: 37351895 PMCID: PMC10292669 DOI: 10.1167/tvst.12.6.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 05/15/2023] [Indexed: 06/24/2023] Open
Abstract
Purpose Mutations in the CRX transcription factor are associated with dominant retinopathies often with more severe macular changes. The CRX-mutant cat (Rdy-A182d2) is the only animal model with the equivalent of the critical retinal region for high-acuity vision, the macula. Heterozygous cats (CRXRdy/+) have a severe phenotype modeling Leber congenital amaurosis. This study reports the distinct ocular phenotype of homozygous cats (CRXRdy/Rdy). Methods Gene expression changes were assessed at both mRNA and protein levels. Changes in globe morphology and retinal structure were analyzed. Results CRXRdy/Rdy cats had high levels of mutant CRX mRNA and protein. The expression of photoreceptor target genes was severely impaired although there were variable effects on the expression of other transcription factors. The photoreceptor cells remained immature and failed to elaborate outer segments consistent with the lack of retinal function. The retinal layers displayed a progressive remodeling with cell loss but maintained overall retinal thickness due to gliosis. Rapid photoreceptor loss largely occurred in the macula-equivalent retinal region. The homozygous cats developed markedly increased ocular globe length. Conclusions The phenotype of CRXRdy/Rdy cats was more severe compared to CRXRdy/+ cats by several metrics. Translational Relevance The CRX-mutant cat is the only model for CRX-retinopathies with a macula-equivalent region. A prominent feature of the CRXRdy/Rdy cat phenotype not detectable in homozygous mouse models was the rapid degeneration of the macula-equivalent retinal region highlighting the value of this large animal model and its future importance in the testing of translational therapies aiming to restore vision.
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Affiliation(s)
- Laurence M. Occelli
- Small Animal Clinical Sciences, Michigan State University, East Lansing, MI, USA
| | - Nicholas M. Tran
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Shiming Chen
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
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4
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Silva CA, Yalnizyan-Carson A, Fernández Busch MV, van Zwieten M, Verhage M, Lohmann C. Activity-dependent regulation of mitochondrial motility in developing cortical dendrites. eLife 2021; 10:62091. [PMID: 34491202 PMCID: PMC8423438 DOI: 10.7554/elife.62091] [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: 08/13/2020] [Accepted: 08/24/2021] [Indexed: 11/13/2022] Open
Abstract
Developing neurons form synapses at a high rate. Synaptic transmission is very energy-demanding and likely requires ATP production by mitochondria nearby. Mitochondria might be targeted to active synapses in young dendrites, but whether such motility regulation mechanisms exist is unclear. We investigated the relationship between mitochondrial motility and neuronal activity in the primary visual cortex of young mice in vivo and in slice cultures. During the first 2 postnatal weeks, mitochondrial motility decreases while the frequency of neuronal activity increases. Global calcium transients do not affect mitochondrial motility. However, individual synaptic transmission events precede local mitochondrial arrest. Pharmacological stimulation of synaptic vesicle release, but not focal glutamate application alone, stops mitochondria, suggesting that an unidentified factor co-released with glutamate is required for mitochondrial arrest. A computational model of synaptic transmission-mediated mitochondrial arrest shows that the developmental increase in synapse number and transmission frequency can contribute substantially to the age-dependent decrease of mitochondrial motility.
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Affiliation(s)
- Catia Ap Silva
- Department of Synapse and Network Development, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | | | - M Victoria Fernández Busch
- Department of Synapse and Network Development, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | - Mike van Zwieten
- Department of Synapse and Network Development, Netherlands Institute for Neuroscience, Amsterdam, Netherlands
| | - Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, University Amsterdam, Amsterdam, Netherlands
| | - Christian Lohmann
- Department of Synapse and Network Development, Netherlands Institute for Neuroscience, Amsterdam, Netherlands.,Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, University Amsterdam, Amsterdam, Netherlands
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5
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Wu Y, Qiu J, Chen S, Chen X, Zhang J, Zhuang J, Liu S, Yang M, Zhou P, Chen H, Ge J, Yu K, Zhuang J. Crx Is Posttranscriptionally Regulated by Light Stimulation in Postnatal Rat Retina. Front Cell Dev Biol 2020; 8:174. [PMID: 32318566 PMCID: PMC7154164 DOI: 10.3389/fcell.2020.00174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 03/02/2020] [Indexed: 11/13/2022] Open
Abstract
Cone rod homeobox (Crx) plays a key role at the center of a regulatory network that coordinates many pathways in the retina. Its abnormal expression induces retinal disorders. However, the underlying regulatory mechanism of Crx expression is not well defined. Here, we present data that show that the levels of Crx mRNA were inconsistent with that of Crx protein in primary retinal neurocytes cultured in light conditions. Crx protein levels were significantly higher (2.56-fold) in cells cultured in the dark than in cells cultured in light, whereas Crx mRNA was not changed in either type of cell. Moreover, the expression of Crx protein showed a significant light intensity-dependent decrease. Consistently, Crx downstream genes rhodopsin and arrestin also decreased in retinal neurocytes upon light exposure. Furthermore, Crx promoter activity assay performed in primary retinal neurocytes further indicated that light exposure and darkness did not affect its inducibility. In addition, the inconsistency between Crx mRNA and protein expression after light exposure was not observed in 661w cells transfected with plasmid pcDNA3.1-Crx, suggesting that the inconsistency between Crx mRNA and protein induced by light was specific to the endogenous Crx. More importantly, this observation was confirmed in vivo in postnatal day 15 (P15) retinas but not in adult retinas, further implicating that the posttranscriptional regulation mechanism may be involved in Crx expression in the developing retina. Therefore, our study sheds light on the mechanism of Crx expression in postnatal rat retina.
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Affiliation(s)
- Yihui Wu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jin Qiu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shuilian Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xi Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jing Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jiejie Zhuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Sian Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Meng Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Pan Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Haoting Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jian Ge
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Keming Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jing Zhuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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6
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Winkler PA, Occelli LM, Petersen-Jones SM. Large Animal Models of Inherited Retinal Degenerations: A Review. Cells 2020; 9:cells9040882. [PMID: 32260251 PMCID: PMC7226744 DOI: 10.3390/cells9040882] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 03/30/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
Studies utilizing large animal models of inherited retinal degeneration (IRD) have proven important in not only the development of translational therapeutic approaches, but also in improving our understanding of disease mechanisms. The dog is the predominant species utilized because spontaneous IRD is common in the canine pet population. Cats are also a source of spontaneous IRDs. Other large animal models with spontaneous IRDs include sheep, horses and non-human primates (NHP). The pig has also proven valuable due to the ease in which transgenic animals can be generated and work is ongoing to produce engineered models of other large animal species including NHP. These large animal models offer important advantages over the widely used laboratory rodent models. The globe size and dimensions more closely parallel those of humans and, most importantly, they have a retinal region of high cone density and denser photoreceptor packing for high acuity vision. Laboratory rodents lack such a retinal region and, as macular disease is a critical cause for vision loss in humans, having a comparable retinal region in model species is particularly important. This review will discuss several large animal models which have been used to study disease mechanisms relevant for the equivalent human IRD.
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7
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Carrillo-Rosas S, Weber C, Fievet L, Messaddeq N, Karam A, Trottier Y. Loss of zebrafish Ataxin-7, a SAGA subunit responsible for SCA7 retinopathy, causes ocular coloboma and malformation of photoreceptors. Hum Mol Genet 2020; 28:912-927. [PMID: 30445451 DOI: 10.1093/hmg/ddy401] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 10/31/2018] [Accepted: 11/10/2018] [Indexed: 12/26/2022] Open
Abstract
Polyglutamine (polyQ) expansion in Ataxin-7 (ATXN7) results in spinocerebellar ataxia type 7 (SCA7) and causes visual impairment. SCA7 photoreceptors progressively lose their outer segments (OSs), a structure essential for their visual function. ATXN7 is a subunit of the transcriptional coactivator Spt-Ada-Gcn5 Acetyltransferase complex, implicated in the development of the visual system in flies. To determine the function of ATXN7 in the vertebrate eye, we have inactivated ATXN7 in zebrafish. While ATXN7 depletion in flies led to gross retinal degeneration, in zebrafish, it primarily results in ocular coloboma, a structural malformation responsible for pediatric visual impairment in humans. ATXN7 inactivation leads to elevated Hedgehog signaling in the forebrain, causing an alteration of proximo-distal patterning of the optic vesicle during early eye development and coloboma. At later developmental stages, malformations of photoreceptors due to incomplete formation of their OSs are observed and correlate with altered expression of crx, a key transcription factor involved in the formation of photoreceptor OS. Therefore, we propose that a primary toxic effect of polyQ expansion is the alteration of ATXN7 function in the daily renewal of OS in SCA7. Together, our data indicate that ATXN7 plays an essential role in vertebrate eye morphogenesis and photoreceptor differentiation, and its loss of function may contribute to the development of human coloboma.
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Affiliation(s)
- Samantha Carrillo-Rosas
- Institute of Genetics and Molecular and Cellular Biology (IGBMC).,Centre National de la Recherche Scientifique, UMR7104.,Institut National de la Santé et de la Recherche Médicale, U1254.,University of Strasbourg, Illkirch, 67000, France
| | - Chantal Weber
- Institute of Genetics and Molecular and Cellular Biology (IGBMC).,Centre National de la Recherche Scientifique, UMR7104.,Institut National de la Santé et de la Recherche Médicale, U1254.,University of Strasbourg, Illkirch, 67000, France
| | - Lorraine Fievet
- Institute of Genetics and Molecular and Cellular Biology (IGBMC).,Centre National de la Recherche Scientifique, UMR7104.,Institut National de la Santé et de la Recherche Médicale, U1254.,University of Strasbourg, Illkirch, 67000, France
| | - Nadia Messaddeq
- Institute of Genetics and Molecular and Cellular Biology (IGBMC).,Centre National de la Recherche Scientifique, UMR7104.,Institut National de la Santé et de la Recherche Médicale, U1254.,University of Strasbourg, Illkirch, 67000, France
| | - Alice Karam
- Institute of Genetics and Molecular and Cellular Biology (IGBMC).,Centre National de la Recherche Scientifique, UMR7104.,Institut National de la Santé et de la Recherche Médicale, U1254.,University of Strasbourg, Illkirch, 67000, France
| | - Yvon Trottier
- Institute of Genetics and Molecular and Cellular Biology (IGBMC).,Centre National de la Recherche Scientifique, UMR7104.,Institut National de la Santé et de la Recherche Médicale, U1254.,University of Strasbourg, Illkirch, 67000, France
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8
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Markitantova Y, Simirskii V. Inherited Eye Diseases with Retinal Manifestations through the Eyes of Homeobox Genes. Int J Mol Sci 2020; 21:E1602. [PMID: 32111086 PMCID: PMC7084737 DOI: 10.3390/ijms21051602] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 02/21/2020] [Accepted: 02/24/2020] [Indexed: 12/14/2022] Open
Abstract
Retinal development is under the coordinated control of overlapping networks of signaling pathways and transcription factors. The paper was conceived as a review of the data and ideas that have been formed to date on homeobox genes mutations that lead to the disruption of eye organogenesis and result in inherited eye/retinal diseases. Many of these diseases are part of the same clinical spectrum and have high genetic heterogeneity with already identified associated genes. We summarize the known key regulators of eye development, with a focus on the homeobox genes associated with monogenic eye diseases showing retinal manifestations. Recent advances in the field of genetics and high-throughput next-generation sequencing technologies, including single-cell transcriptome analysis have allowed for deepening of knowledge of the genetic basis of inherited retinal diseases (IRDs), as well as improve their diagnostics. We highlight some promising avenues of research involving molecular-genetic and cell-technology approaches that can be effective for IRDs therapy. The most promising neuroprotective strategies are aimed at mobilizing the endogenous cellular reserve of the retina.
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9
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Stefanov A, Novelli E, Strettoi E. Inner retinal preservation in the photoinducible I307N rhodopsin mutant mouse, a model of autosomal dominant retinitis pigmentosa. J Comp Neurol 2019; 528:1502-1522. [PMID: 31811649 PMCID: PMC7187456 DOI: 10.1002/cne.24838] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 12/03/2019] [Accepted: 12/03/2019] [Indexed: 12/20/2022]
Abstract
Rod‐cone degenerations, for example, retinitis pigmentosa are leading causes of blindness worldwide. Despite slow disease progression in humans, vision loss is inevitable; therefore, development of vision restoration strategies is crucial. Among others, promising approaches include optogenetics and prosthetic implants, which aim to bypass lost photoreceptors (PRs). Naturally, the efficacy of these therapeutic strategies will depend on inner retinal structural and functional preservation. The present study shows that in photoinducible I307N rhodopsin mice (Translational Vision Research Model 4 [Tvrm4]), a 12k lux light exposure eliminates PRs in the central retina in 1 week, but interneurons and their synapses are maintained for as long as 9 weeks postinduction. Despite bipolar cell dendritic retraction and moderate loss of horizontal cells, the survival rate of various cell types is very high. Significant preservation of conventional synapses and gap junctions in the inner plexiform layer is also observed. We found the number of synaptic ribbons to gradually decline and their ultrastructure to become transiently abnormal, although based on our findings intrinsic retinal architecture is maintained despite complete loss of PRs. Unlike common rodent models of PR degeneration, where the disease phenotype often interferes with retinal development, in Tvrm4 mice, the degenerative process can be induced after retinal development is complete. This time course more closely mimics the timing of disease onset in affected patients. Stability of the inner retina found in these mutants 2 months after PR degeneration suggests moderate, stereotyped remodeling in the early stages of the human disease and represents a promising finding for prompt approaches of vision restoration.
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Affiliation(s)
- Antonia Stefanov
- Institute of Neuroscience, Italian National Research Council - CNR, Pisa, Italy.,Regional Doctoral School of Neuroscience, University of Florence, Florence, Italy
| | - Elena Novelli
- Institute of Neuroscience, Italian National Research Council - CNR, Pisa, Italy
| | - Enrica Strettoi
- Institute of Neuroscience, Italian National Research Council - CNR, Pisa, Italy
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10
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He J, Zhao C, Dai J, Weng CH, Bian BSJ, Gong Y, Ge L, Fang Y, Liu H, Xu H, Yin ZQ. Microglia Mediate Synaptic Material Clearance at the Early Stage of Rats With Retinitis Pigmentosa. Front Immunol 2019; 10:912. [PMID: 31105708 PMCID: PMC6499027 DOI: 10.3389/fimmu.2019.00912] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 04/09/2019] [Indexed: 12/11/2022] Open
Abstract
Resident microglia are the main immune cells in the retina and play a key role in the pathogenesis of retinitis pigmentosa (RP). Many previous studies on the roles of microglia mainly focused on the neurotoxicity or neuroprotection of photoreceptors, while their contributions to synaptic remodeling of neuronal circuits in the retina of early RP remained unclarified. In the present study, we used Royal College of Surgeons (RCS) rats, a classic RP model characterized by progressive microglia activation and synapse loss, to investigate the constitutive effects of microglia on the synaptic lesions and ectopic neuritogenesis. Rod degeneration resulted in synapse disruption and loss in the outer plexiform layer (OPL) at the early stage of RP. Coincidentally, the resident microglia in the OPL increased phagocytosis and mainly engaged in phagocytic engulfment of postsynaptic mGluR6 of rod bipolar cells (RBCs). Complement pathway might be involved in clearance of postsynaptic elements of RBCs by microglia. We pharmacologically deleted microglia using a CSF1 receptor (CSF1R) inhibitor to confirm this finding, and found that it caused the accumulation of postsynaptic mGluR6 levels and increased the number and length of ectopic dendrites in the RBCs. Interestingly, the numbers of presynaptic sites expressing CtBP2 and colocalized puncta in the OPL of RCS rats were not affected by microglia elimination. However, sustained microglial depletion led to progressive functional deterioration in the retinal responses to light in RCS rats. Based on our results, microglia mediated the remodeling of RBCs by phagocytosing postsynaptic materials and inhibiting ectopic neuritogenesis, contributing to delay the deterioration of vision at the early stage of RP.
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Affiliation(s)
- Juncai He
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Congjian Zhao
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Jiaman Dai
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Chuan Huang Weng
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Bai Shi Jiao Bian
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yu Gong
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Lingling Ge
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Yajie Fang
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Hui Liu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Haiwei Xu
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
| | - Zheng Qin Yin
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Amy Medical University), Chongqing, China.,Key Lab of Visual Damage and Regeneration and Restoration of Chongqing, Chongqing, China
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11
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Tsai ELS, Ortin-Martinez A, Gurdita A, Comanita L, Yan N, Smiley S, Delplace V, Shoichet MS, Nickerson PEB, Wallace VA. Modeling of Photoreceptor Donor-Host Interaction Following Transplantation Reveals a Role for Crx, Müller Glia, and Rho/ROCK Signaling in Neurite Outgrowth. Stem Cells 2019; 37:529-541. [DOI: 10.1002/stem.2985] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 12/20/2018] [Accepted: 01/10/2019] [Indexed: 12/19/2022]
Affiliation(s)
- En L. S. Tsai
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
- Department of Laboratory Medicine and Pathobiology; University of Toronto; Toronto Ontario Canada
| | - Arturo Ortin-Martinez
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
| | - Akshay Gurdita
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
- Department of Laboratory Medicine and Pathobiology; University of Toronto; Toronto Ontario Canada
| | - Lacrimioara Comanita
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
| | - Nicole Yan
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
- Department of Laboratory Medicine and Pathobiology; University of Toronto; Toronto Ontario Canada
| | - Sheila Smiley
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
| | - Vianney Delplace
- Department of Chemical Engineering & Applied Chemistry; University of Toronto; Toronto Ontario Canada
| | - Molly S. Shoichet
- Department of Chemical Engineering & Applied Chemistry; University of Toronto; Toronto Ontario Canada
- Institute of Biomaterials and Biomedical Engineering; University of Toronto; Toronto Ontario Canada
| | - Philip E. B. Nickerson
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
| | - Valerie A. Wallace
- Donald K. Johnson Eye Institute, Krembil Research Institute; University Health Network; Toronto Ontario Canada
- Department of Laboratory Medicine and Pathobiology; University of Toronto; Toronto Ontario Canada
- Department of Ophthalmology and Vision Sciences; University of Toronto; Toronto Ontario Canada
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12
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Abstract
This chapter provides an overview of the early developmental origins of six ocular tissues: the cornea, lens, ciliary body, iris, neural retina, and retina pigment epithelium. Many of these tissue types are concurrently specified and undergo a complex set of morphogenetic movements that facilitate their structural interconnection. Within the context of vertebrate eye organogenesis, we also discuss the genetic hierarchies of transcription factors and signaling pathways that regulate growth, patterning, cell type specification and differentiation.
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Affiliation(s)
- Joel B Miesfeld
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, Davis, CA, United States
| | - Nadean L Brown
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, Davis, CA, United States.
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13
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Rpgrip1 is required for rod outer segment development and ciliary protein trafficking in zebrafish. Sci Rep 2017; 7:16881. [PMID: 29203866 PMCID: PMC5715152 DOI: 10.1038/s41598-017-12838-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 09/14/2017] [Indexed: 12/23/2022] Open
Abstract
Mutations in the RPGR-interacting protein 1 (RPGRIP1) gene cause recessive Leber congenital amaurosis (LCA), juvenile retinitis pigmentosa (RP) and cone-rod dystrophy. RPGRIP1 interacts with other retinal disease-causing proteins and has been proposed to have a role in ciliary protein transport; however, its function remains elusive. Here, we describe a new zebrafish model carrying a nonsense mutation in the rpgrip1 gene. Rpgrip1homozygous mutants do not form rod outer segments and display mislocalization of rhodopsin, suggesting a role for RPGRIP1 in rhodopsin-bearing vesicle trafficking. Furthermore, Rab8, the key regulator of rhodopsin ciliary trafficking, was mislocalized in photoreceptor cells of rpgrip1 mutants. The degeneration of rod cells is early onset, followed by the death of cone cells. These phenotypes are similar to that observed in LCA and juvenile RP patients. Our data indicate RPGRIP1 is necessary for rod outer segment development through regulating ciliary protein trafficking. The rpgrip1 mutant zebrafish may provide a platform for developing therapeutic treatments for RP patients.
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14
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Musser JM, Arendt D. Loss and gain of cone types in vertebrate ciliary photoreceptor evolution. Dev Biol 2017; 431:26-35. [DOI: 10.1016/j.ydbio.2017.08.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Revised: 08/28/2017] [Accepted: 08/30/2017] [Indexed: 01/09/2023]
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15
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Møller M, Rath MF, Ludvigsen M, Honoré B, Vorum H. Diurnal expression of proteins in the retina of the blind cone-rod homeobox (Crx -/- ) mouse and the 129/Sv mouse: a proteomic study. Acta Ophthalmol 2017; 95:717-726. [PMID: 28371363 DOI: 10.1111/aos.13429] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 02/06/2017] [Indexed: 01/06/2023]
Abstract
PURPOSE The vertebrate retina contains a circadian clock participating in adaptations to day and night vision. This peripheral clock is independent of the master clock in the suprachiasmatic nucleus (SCN). The retinal clock is located in several cell types, including the photoreceptors. To investigate the role of the circadian clock of the photoreceptor cells in regulation of retinal protein rhythms, we analysed diurnal protein expression in the photoreceptor-deficient cone-rod homeobox knockout mouse (Crx-/- ) and the 129/Sv mouse. METHODS 2D gels were made from retinal homogenates of 129/Sv and Crx-/- mice killed at midday and midnight. Stained gels were analysed by use of PDQuest 2D gel analysis software. After trypsin digestion of differential expressed spots, the proteins were identified by LC-MS/MS using a nano-liquid chromatograph connected to a Q-TOF Premier mass spectrometer. These data were used to search the SWISS-PROT database. RESULTS Both the retinae of the control and the Crx-/- mice exhibited diurnal proteins rhythms. As expected, proteins involved in phototransduction were not detected in the Crx-/- mouse; in this phenotype, however, proteins from spots showing diurnal rhythms were specifically identified as enzymes involved in glucose metabolism, Krebs cycle, and mitochondrial enzymes. Data are available via ProteomeXchange with identifier PXD005556. CONCLUSION We show diurnal protein rhythms in the retina of a mouse lacking the rods and cones. The diurnal protein rhythms in this genotype, lacking the circadian clock of the photoreceptors, might be caused by a circadian clock in other retinal cell types or a direct light input to the retina.
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Affiliation(s)
- Morten Møller
- Department of Neuroscience and Pharmacology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - Martin Fredensborg Rath
- Department of Neuroscience and Pharmacology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - Maja Ludvigsen
- Department of Clinical Medicine; Aarhus University; Aarhus Denmark
- Department of Hematology; Aarhus University Hospital; Aarhus Denmark
| | - Bent Honoré
- Department of Biomedicine; Aarhus University; Aarhus Denmark
| | - Henrik Vorum
- Department of Ophthalmology; Aalborg University Hospital; Aalborg Denmark
- Department of Clinical Medicine; Aalborg University; Aalborg Denmark
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16
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Occelli LM, Tran NM, Narfström K, Chen S, Petersen-Jones SM. CrxRdy Cat: A Large Animal Model for CRX-Associated Leber Congenital Amaurosis. Invest Ophthalmol Vis Sci 2017; 57:3780-92. [PMID: 27427859 PMCID: PMC4960999 DOI: 10.1167/iovs.16-19444] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Purpose Mutations in the retinal transcription factor cone-rod homeobox (CRX) gene result in severe dominant retinopathies. A large animal model, the Rdy cat, carrying a spontaneous frameshift mutation in Crx, was reported previously. The present study aimed to further understand pathogenesis in this model by thoroughly characterizing the Rdy retina. Methods Structural and functional changes were found in a comparison between the retinas of CrxRdy/+ kittens and those of wild-type littermates and were determined at various ages by fundus examination, electroretinography (ERG), optical coherence tomography, and histologic analyses. RNA and protein expression changes of Crx and key target genes were analyzed using quantitative reverse-transcribed PCR, Western blot analysis, and immunohistochemistry. Transcription activity of the mutant Crx was measured by a dual-luciferase transactivation assay. Results CrxRdy/+ kittens had no recordable cone ERGs. Rod responses were delayed in development and markedly reduced at young ages and lost by 20 weeks. Photoreceptor outer segment development was incomplete and was followed by progressive outer retinal thinning starting in the cone-rich area centralis. Expression of cone and rod Crx target genes was significantly down-regulated. The mutant Crx allele was overexpressed, leading to high levels of the mutant protein lacking transactivation activity. Conclusions The CrxRdy mutation exerts a dominant negative effect on wild-type Crx by overexpressing mutant protein. These findings, consistent with those of studies in a mouse model, support a conserved pathogenic mechanism for CRX frameshift mutations. The similarities between the feline eye and the human eye with the presence of a central region of high cone density makes the CrxRdy/+ cat a valuable model for preclinical testing of therapies for dominant CRX diseases.
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Affiliation(s)
- Laurence M Occelli
- Small Animal Clinical Sciences Michigan State University, East Lansing, Michigan, United States
| | - Nicholas M Tran
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States
| | - Kristina Narfström
- Department of Veterinary Medicine and Surgery, University of Missouri-Columbia, Columbia, Missouri, United States
| | - Shiming Chen
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States
| | - Simon M Petersen-Jones
- Small Animal Clinical Sciences Michigan State University, East Lansing, Michigan, United States
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17
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Temporal profiling of photoreceptor lineage gene expression during murine retinal development. Gene Expr Patterns 2017; 23-24:32-44. [PMID: 28288836 DOI: 10.1016/j.gep.2017.03.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 02/03/2017] [Accepted: 03/07/2017] [Indexed: 02/08/2023]
Abstract
Rod and cone photoreceptors are photosensitive cells in the retina that convert light to electrical signals that are transmitted to visual processing centres in the brain. During development, cones and rods are generated from a common pool of multipotent retinal progenitor cells (RPCs) that also give rise to other retinal cell types. Cones and rods differentiate in two distinct waves, peaking in mid-embryogenesis and the early postnatal period, respectively. As RPCs transition from making cones to generating rods, there are changes in the expression profiles of genes involved in photoreceptor cell fate specification and differentiation. To better understand the temporal transition from cone to rod genesis, we assessed the timing of onset and offset of expression of a panel of 11 transcription factors and 7 non-transcription factors known to function in photoreceptor development, examining their expression between embryonic day (E) 12.5 and postnatal day (P) 60. Transcription factor expression in the photoreceptor layer was observed as early as E12.5, beginning with Crx, Otx2, Rorb, Neurod1 and Prdm1 expression, followed at E15.5 with the expression of Thrb, Neurog1, Sall3 and Rxrg expression, and at P0 by Nrl and Nr2e3 expression. Of the non-transcription factors, peanut agglutinin lectin staining and cone arrestin protein were observed as early as E15.5 in the developing outer nuclear layer, while transcripts for the cone opsins Opn1mw and Opn1sw and Recoverin protein were detected in photoreceptors by P0. In contrast, Opn1mw and Opn1sw protein were not observed in cones until P7, when rod-specific Gnat1 transcripts and rhodopsin protein were also detected. We have thus identified four transitory stages during murine retina photoreceptor differentiation marked by the period of onset of expression of new photoreceptor lineage genes. By characterizing these stages, we have clarified the dynamic nature of gene expression during the period when photoreceptor identities are progressively acquired during development.
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18
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Kovács-Valasek A, Szabadfi K, Dénes V, Szalontai B, Tamás A, Kiss P, Szabó A, Setalo G, Reglődi D, Gábriel R. Accelerated retinal aging in PACAP knock-out mice. Neuroscience 2017; 348:1-10. [PMID: 28215987 DOI: 10.1016/j.neuroscience.2017.02.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/31/2017] [Accepted: 02/02/2017] [Indexed: 12/26/2022]
Abstract
Pituitary adenylate cyclase activating polypeptide (PACAP) is a neurotrophic and neuroprotective peptide. PACAP and its receptors are widely distributed in the retina. A number of reports provided evidence that PACAP is neuroprotective in retinal degenerations. The current study compared retina cell type-specific differences in young (3-4months) and aged adults (14-16months), of wild-type (WT) mice and knock-out (KO) mice lacking endogenous PACAP production during the course of aging. Histological, immunocytochemical and Western blot examinations were performed. The staining for standard neurochemical markers (tyrosine hydroxylase for dopaminergic cells, calbindin 28 kDa for horizontal cells, protein kinase Cα for rod bipolar cells) of young adult PACAP KO retinas showed no substantial alterations compared to young adult WT retinas, except for the specific PACAP receptor (PAC1-R) staining. We could not detect PAC1-R immunoreactivity in bipolar and horizontal cells in young adult PACAP KO animals. Some other age-related changes were observed only in the PACAP KO mice only. These alterations included horizontal and rod bipolar cell dendritic sprouting into the photoreceptor layer and decreased ganglion cell number. Also, Müller glial cells showed elevated GFAP expression compared to the aging WT retinas. Furthermore, Western blot analyses revealed significant differences between the phosphorylation state of ERK1/2 and JNK in KO mice, indicating alterations in the MAPK signaling pathway. These results support the conclusion that endogenous PACAP contributes to protection against aging of the nervous system.
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Affiliation(s)
- Andrea Kovács-Valasek
- Department of Experimental Zoology and Neurobiology, University of Pécs, Pécs, Hungary; Department of János Szentágothai Research Center, University of Pécs, Pécs, Hungary
| | - Krisztina Szabadfi
- Department of Experimental Zoology and Neurobiology, University of Pécs, Pécs, Hungary
| | - Viktória Dénes
- Department of Experimental Zoology and Neurobiology, University of Pécs, Pécs, Hungary
| | - Bálint Szalontai
- Department of Experimental Zoology and Neurobiology, University of Pécs, Pécs, Hungary
| | - Andrea Tamás
- Department of Anatomy, University of Pécs, Pécs, Hungary
| | - Péter Kiss
- Department of Anatomy, University of Pécs, Pécs, Hungary
| | - Aliz Szabó
- Department of Biochemistry and Medicinal Chemistry, University of Pécs, Pécs, Hungary
| | - Gyorgy Setalo
- Department of Medical Biology, University of Pécs, Pécs, Hungary; Department of János Szentágothai Research Center, University of Pécs, Pécs, Hungary
| | - Dóra Reglődi
- Department of Anatomy, University of Pécs, Pécs, Hungary
| | - Robert Gábriel
- Department of Experimental Zoology and Neurobiology, University of Pécs, Pécs, Hungary; Department of János Szentágothai Research Center, University of Pécs, Pécs, Hungary.
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Dong Y, Cai X, Wu Y, Liu Y, Deng L, Chen H. Insights from Genetic Model Systems of Retinal Degeneration: Role of Epsins in Retinal Angiogenesis and VEGFR2 Signaling. JOURNAL OF NATURE AND SCIENCE 2017; 3:e281. [PMID: 28191500 PMCID: PMC5303005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The retina is a light sensitive tissue that contains specialized photoreceptor cells called rods and cones which process visual signals. These signals are relayed to the brain through interneurons and the fibers of the optic nerve. The retina is susceptible to a variety of degenerative diseases, including age-related macular degeneration (AMD), diabetic retinopathy (DR), retinitis pigmentosa (RP) and other inherited retinal degenerations. In order to reveal the mechanism underlying these diseases and to find methods for the prevention/treatment of retinal degeneration, animal models have been generated to mimic human eye diseases. In this paper, several well-characterized and commonly used animal models are reviewed. Of particular interest are the contributions of these models to our understanding of the mechanisms of retinal degeneration and thereby providing novel treatment options including gene therapy, stem cell therapy, nanomedicine, and CRISPR/Cas9 genome editing. Role of newly-identified adaptor protein epsins from our laboratory is discussed in retinal angiogenesis and VEGFR2 signaling.
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Affiliation(s)
- Yunzhou Dong
- Vascular Biology Program, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Xue Cai
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Yong Wu
- Department of Internal Medicine, Charles R. Drew University of Medicine & Sciences, University of California School of Medicine, Los Angeles, CA 90059, USA
| | - Yanjun Liu
- Department of Internal Medicine, Charles R. Drew University of Medicine & Sciences, University of California School of Medicine, Los Angeles, CA 90059, USA
| | - Lin Deng
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Hong Chen
- Vascular Biology Program, Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA
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20
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Murphy D, Cieply B, Carstens R, Ramamurthy V, Stoilov P. The Musashi 1 Controls the Splicing of Photoreceptor-Specific Exons in the Vertebrate Retina. PLoS Genet 2016; 12:e1006256. [PMID: 27541351 PMCID: PMC4991804 DOI: 10.1371/journal.pgen.1006256] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 07/22/2016] [Indexed: 01/08/2023] Open
Abstract
Alternative pre-mRNA splicing expands the coding capacity of eukaryotic genomes, potentially enabling a limited number of genes to govern the development of complex anatomical structures. Alternative splicing is particularly prevalent in the vertebrate nervous system, where it is required for neuronal development and function. Here, we show that photoreceptor cells, a type of sensory neuron, express a characteristic splicing program that affects a broad set of transcripts and is initiated prior to the development of the light sensing outer segments. Surprisingly, photoreceptors lack prototypical neuronal splicing factors and their splicing profile is driven to a significant degree by the Musashi 1 (MSI1) protein. A striking feature of the photoreceptor splicing program are exons that display a "switch-like" pattern of high inclusion levels in photoreceptors and near complete exclusion outside of the retina. Several ubiquitously expressed genes that are involved in the biogenesis and function of primary cilia produce highly photoreceptor specific isoforms through use of such "switch-like" exons. Our results suggest a potential role for alternative splicing in the development of photoreceptors and the conversion of their primary cilia to the light sensing outer segments.
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Affiliation(s)
- Daniel Murphy
- Department of Biochemistry, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia, United States of America
| | - Benjamin Cieply
- Department of Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Russ Carstens
- Department of Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Visvanathan Ramamurthy
- Departments of Biochemistry, Ophthalmology and Center for Neuroscience, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia, United States of America
| | - Peter Stoilov
- Department of Biochemistry and Cancer Institute, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia, United States of America
- * E-mail:
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Abstract
Photoreceptors have been the most intensively studied retinal cell type. Early lineage studies showed that photoreceptors are produced by retinal progenitor cells (RPCs) that produce only photoreceptor cells and by RPCs that produce both photoreceptor cells and other retinal cell types. More recent lineage studies have shown that there are intrinsic, molecular differences among these RPCs and that these molecular differences operate in gene regulatory networks (GRNs) that lead to the choice of the rod versus the cone fate. In addition, there are GRNs that lead to the choice of a photoreceptor fate and that of another retinal cell type. An example of such a GRN is one that drives the binary fate choice between a rod photoreceptor and bipolar cell. This GRN has many elements, including both feedforward and feedback regulatory loops, highlighting the complexity of such networks. This and other examples of retinal cell fate determination are reviewed here, focusing on the events that direct the choice of rod and cone photoreceptor fate.
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Affiliation(s)
- Constance L Cepko
- Departments of Genetics and Ophthalmology, Howard Hughes Medical Institute, Harvard Medical School, Boston, Massachusetts 02115;
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22
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Soto F, Kerschensteiner D. Synaptic remodeling of neuronal circuits in early retinal degeneration. Front Cell Neurosci 2015; 9:395. [PMID: 26500497 PMCID: PMC4595653 DOI: 10.3389/fncel.2015.00395] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/22/2015] [Indexed: 11/27/2022] Open
Abstract
Photoreceptor degenerations are a major cause of blindness and among the most common forms of neurodegeneration in humans. Studies of mouse models revealed that synaptic dysfunction often precedes photoreceptor degeneration, and that abnormal synaptic input from photoreceptors to bipolar cells causes circuits in the inner retina to become hyperactive. Here, we provide a brief overview of frequently used mouse models of photoreceptor degenerations. We then discuss insights into circuit remodeling triggered by early synaptic dysfunction in the outer and hyperactivity in the inner retina. We discuss these insights in the context of other experimental manipulations of synaptic function and activity. Knowledge of the plasticity and early remodeling of retinal circuits will be critical for the design of successful vision rescue strategies.
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Affiliation(s)
- Florentina Soto
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine in St. Louis St. Louis, MO, USA
| | - Daniel Kerschensteiner
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine in St. Louis St. Louis, MO, USA ; Department of Anatomy and Neurobiology, Washington University School of Medicine in St. Louis St. Louis, MO, USA ; Department of Biomedical Engineering, Washington University School of Medicine in St. Louis St. Louis, MO, USA ; Hope Center for Neurological Disorders, Washington University School of Medicine in St. Louis St. Louis, MO, USA
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23
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Mencarelli C, Pichaud F. Orthodenticle Is Required for the Expression of Principal Recognition Molecules That Control Axon Targeting in the Drosophila Retina. PLoS Genet 2015; 11:e1005303. [PMID: 26114289 PMCID: PMC4482733 DOI: 10.1371/journal.pgen.1005303] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/27/2015] [Indexed: 11/18/2022] Open
Abstract
Parallel processing of neuronal inputs relies on assembling neural circuits into distinct synaptic-columns and layers. This is orchestrated by matching recognition molecules between afferent growth cones and target areas. Controlling the expression of these molecules during development is crucial but not well understood. The developing Drosophila visual system is a powerful genetic model for addressing this question. In this model system, the achromatic R1-6 photoreceptors project their axons in the lamina while the R7 and R8 photoreceptors, which are involved in colour detection, project their axons to two distinct synaptic-layers in the medulla. Here we show that the conserved homeodomain transcription factor Orthodenticle (Otd), which in the eye is a main regulator of rhodopsin expression, is also required for R1-6 photoreceptor synaptic-column specific innervation of the lamina. Our data indicate that otd function in these photoreceptors is largely mediated by the recognition molecules flamingo (fmi) and golden goal (gogo). In addition, we find that otd regulates synaptic-layer targeting of R8. We demonstrate that during this process, otd and the R8-specific transcription factor senseless/Gfi1 (sens) function as independent transcriptional inputs that are required for the expression of fmi, gogo and the adhesion molecule capricious (caps), which govern R8 synaptic-layer targeting. Our work therefore demonstrates that otd is a main component of the gene regulatory network that regulates synaptic-column and layer targeting in the fly visual system. Establishing neural circuits during brain development relies on the ability for neurons to find their appropriate targets, a task that depends on recognition molecules whose expression must be tightly controlled. Very little is known of the factors that control the expression of these molecules. Here we have used the genetically amenable fly retina to address this issue. We identify Orthodenticle, a protein involved in mammalian brain development, as a main component of a new genetic cascade controlling the expression of recognition molecules that govern the wiring of the fly retina. Our work raises the issue that Orthodenticle might play a similar role in mammals. It also sheds new light on the genetic basis for wiring a model neural circuit during development.
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Affiliation(s)
- Chiara Mencarelli
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
| | - Franck Pichaud
- MRC Laboratory for Molecular Cell Biology, University College London, London, United Kingdom
- * E-mail:
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24
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Omori Y, Kitamura T, Yoshida S, Kuwahara R, Chaya T, Irie S, Furukawa T. Mef2d is essential for the maturation and integrity of retinal photoreceptor and bipolar cells. Genes Cells 2015; 20:408-26. [PMID: 25757744 DOI: 10.1111/gtc.12233] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 01/30/2015] [Indexed: 11/29/2022]
Abstract
Mef2 transcription factors play a crucial role in cardiac and skeletal muscle differentiation. We found that Mef2d is highly expressed in the mouse retina and its loss causes photoreceptor degeneration similar to that observed in human retinitis pigmentosa patients. Electroretinograms (ERGs) were severely impaired in Mef2d-/- mice. Immunohistochemistry showed that photoreceptor and bipolar cell synapse protein levels severely decreased in the Mef2d-/- retina. Expression profiling by microarray analysis showed that Mef2d is required for the expression of various genes in photoreceptor and bipolar cells, including cone arrestin, Guca1b, Pde6h and Cacna1s, which encode outer segment and synapse proteins. We also observed that Mef2d synergistically activates the cone arrestin (Arr3) promoter with Crx, suggesting that functional cooperation between Mef2d and Crx is important for photoreceptor cell gene regulation. Taken together, our results show that Mef2d is essential for photoreceptor and bipolar cell gene expression, either independently or cooperatively with Crx.
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Affiliation(s)
- Yoshihiro Omori
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan; JST, CREST, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
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Tran NM, Chen S. Mechanisms of blindness: animal models provide insight into distinct CRX-associated retinopathies. Dev Dyn 2014; 243:1153-66. [PMID: 24888636 DOI: 10.1002/dvdy.24151] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/24/2014] [Accepted: 05/10/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The homeodomain transcription factor CRX is a crucial regulator of mammalian photoreceptor gene expression. Mutations in the human CRX gene are associated with dominant inherited retinopathies Retinitis Pigmentosa (RP), Cone-Rod Dystrophy (CoRD), and Leber Congenital Amaurosis (LCA), of varying severity. In vitro and in vivo assessment of mutant CRX proteins have revealed pathogenic mechanisms for several mutations, but no comprehensive mutation-disease correlation has yet been reported. RESULTS Here we describe four different classes of disease-causing CRX mutations, characterized by mutation type, pathogenetic mechanism, and the molecular activity of the mutant protein: (1) hypomorphic missense mutations with reduced DNA binding, (2) antimorphic missense mutations with variable DNA binding, (3) antimorphic frameshift/nonsense mutations with intact DNA binding, and (4) antimorphic frameshift mutations with reduced DNA binding. Mammalian models representing three of these classes have been characterized. CONCLUSIONS Models carrying Class I mutations display a mild dominant retinal phenotype and recessive LCA, while models carrying Class III and IV mutations display characteristically distinct dominant LCA phenotypes. These animal models also reveal unexpected pathogenic mechanisms underlying CRX-associated retinopathies. The complexity of genotype-phenotype correlation for CRX-associated diseases highlights the value of developing comprehensive "true-to-disease" animal models for understanding pathologic mechanisms and testing novel therapeutic approaches.
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Affiliation(s)
- Nicholas M Tran
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, Missouri
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Tran NM, Zhang A, Zhang X, Huecker JB, Hennig AK, Chen S. Mechanistically distinct mouse models for CRX-associated retinopathy. PLoS Genet 2014; 10:e1004111. [PMID: 24516401 PMCID: PMC3916252 DOI: 10.1371/journal.pgen.1004111] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 12/02/2013] [Indexed: 12/02/2022] Open
Abstract
Cone-rod homeobox (CRX) protein is a “paired-like” homeodomain transcription factor that is essential for regulating rod and cone photoreceptor transcription. Mutations in human CRX are associated with the dominant retinopathies Retinitis Pigmentosa (RP), Cone-Rod Dystrophy (CoRD) and Leber Congenital Amaurosis (LCA), with variable severity. Heterozygous Crx Knock-Out (KO) mice (“+/−”) have normal vision as adults and fail to model the dominant human disease. To investigate how different mutant CRX proteins produce distinct disease pathologies, we generated two Crx Knock-IN (K-IN) mouse models: CrxE168d2 (“E168d2”) and CrxR90W (“R90W”). E168d2 mice carry a frameshift mutation in the CRX activation domain, Glu168del2, which is associated with severe dominant CoRD or LCA in humans. R90W mice carry a substitution mutation in the CRX homeodomain, Arg90Trp, which is associated with dominant mild late-onset CoRD and recessive LCA. As seen in human patients, heterozygous E168d2 (“E168d2/+”) but not R90W (“R90W/+”) mice show severely impaired retinal function, while mice homozygous for either mutation are blind and undergo rapid photoreceptor degeneration. E168d2/+ mice also display abnormal rod/cone morphology, greater impairment of CRX target gene expression than R90W/+ or +/− mice, and undergo progressive photoreceptor degeneration. Surprisingly, E168d2/+ mice express more mutant CRX protein than wild-type CRX. E168d2neo/+, a subline of E168d2 with reduced mutant allele expression, displays a much milder retinal phenotype, demonstrating the impact of Crx expression level on disease severity. Both CRX[E168d2] and CRX[R90W] proteins fail to activate transcription in vitro, but CRX[E168d2] interferes more strongly with the function of wild type (WT) CRX, supporting an antimorphic mechanism. E168d2 and R90W are mechanistically distinct mouse models for CRX-associated disease that will allow the elucidation of molecular mechanisms and testing of novel therapeutic approaches for different forms of CRX-associated disease. The transcription factor Cone-Rod Homeobox (CRX) plays a central role in regulating gene expression of rod and cone photoreceptors, the primary light sensing cells of the retina. Mutations in the human CRX gene have been associated with the retinal degeneration diseases Retinitis Pigmentosa (RP), Cone-Rod Dystrophy (CoRD) and Leber Congential Amaurosis (LCA). These diseases cause progressive and permanent loss of vision, vary widely in age of onset and severity, and are currently untreatable. To understand how mutations in CRX cause distinct forms of retinal disease, we have genetically engineered mice to carry human disease-causing mutations in their Crx gene. These mouse lines accurately recapitulate distinct forms of CRX-associated disease, demonstrating that different classes of CRX mutations are responsible for phenotype variability in humans. We have characterized the pathology of these mice and identified critical mechanisms of disease. In addition, we have discovered that modifying the level of mutant protein had a dramatic effect on disease pathology in one mutant model, suggesting that targeted therapy against the mutant CRX could be an effective treatment strategy. These mouse models will allow for the testing of novel therapeutic strategies for retinal diseases caused by CRX mutations.
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Affiliation(s)
- Nicholas M Tran
- Ph.D. program in Molecular Genetics and Genomics, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
| | - Alan Zhang
- College of Arts & Sciences, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
| | - Xiaodong Zhang
- Department of Ophthalmology and Visual Sciences, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
| | - Julie B Huecker
- Department of Ophthalmology and Visual Sciences, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
| | - Anne K Hennig
- Department of Ophthalmology and Visual Sciences, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
| | - Shiming Chen
- Ph.D. program in Molecular Genetics and Genomics, Washington University in Saint Louis, Saint Louis, Missouri, United States of America ; Department of Ophthalmology and Visual Sciences, Washington University in Saint Louis, Saint Louis, Missouri, United States of America ; Department of Developmental Biology, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
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Ferguson LR, Dominguez II JM, Balaiya S, Grover S, Chalam KV. Retinal Thickness Normative Data in Wild-Type Mice Using Customized Miniature SD-OCT. PLoS One 2013; 8:e67265. [PMID: 23826252 PMCID: PMC3695045 DOI: 10.1371/journal.pone.0067265] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Accepted: 05/20/2013] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE To report normative data for retinal thickness in wild-type C57BL/6 mouse utilizing a miniature SD-OCT system. METHODS THIRTY ADULT MICE (RANGE: 3-5 months) were anesthetized and secured into the Bioptigen Spectral Domain Ophthalmic Imaging System. Right eye SD-OCT images were standardized by centralizing the optic nerve head (ONH) prior to image acquisition. Global and quadrant total retinal thickness (TRT) values were measured from retinal nerve fiber layer to retinal pigment epithelial layer. Posterior segment analyses also included the outer retinal layer (ORL) and inner retinal layer (IRL). Further sublayer analyses of four layers from the ORL and three layers comprising the IRL were also performed. RESULTS The overall mean±SD global TRT in a C57BL/6 mouse model was 204.41±5.19 µm. Quadrant mean TRT values were 204.85±5.81 µm inferiorly, 204.97±6.71 µm nasally, 205.08±5.44 µm temporally, and 202.74±4.85 µm superiorly. Mean±SD thickness for ORL, and IRL were 126.37±10.01 µm, and 107.03±10.98 µm respectively. The mean±SD estimates for the four layers of the ORL were 18.23±2.73 µm, 26.04±4.21 µm, 63.8±6.23 µm, and 19.22±4.34 µm. Mean±SD values for the three IRL sublayers were 27.82±4.04 µm, 59.62±6.66 µm and 19.12±3.71 µm. CONCLUSION This study established normative values for the total retinal thickness and sublayer thickness for the wild-type C57BL/6 mice. Moreover, it provides a standard of retinal morphology, in a commonly used animal model, for evaluating therapeutic interventions and retinal disease pathophysiology.
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Affiliation(s)
- Lee R. Ferguson
- Department of Ophthalmology, University of Florida College of Medicine, Jacksonville, Florida, United States of America
| | - James M. Dominguez II
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, Florida, United States of America
| | - Sankarathi Balaiya
- Department of Ophthalmology, University of Florida College of Medicine, Jacksonville, Florida, United States of America
| | - Sandeep Grover
- Department of Ophthalmology, University of Florida College of Medicine, Jacksonville, Florida, United States of America
| | - Kakarla V. Chalam
- Department of Ophthalmology, University of Florida College of Medicine, Jacksonville, Florida, United States of America
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Sen S, Reichert H, VijayRaghavan K. Conserved roles of ems/Emx and otd/Otx genes in olfactory and visual system development in Drosophila and mouse. Open Biol 2013; 3:120177. [PMID: 23635521 PMCID: PMC3866872 DOI: 10.1098/rsob.120177] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The regional specialization of brain function has been well documented in the mouse and fruitfly. The expression of regulatory factors in specific regions of the brain during development suggests that they function to establish or maintain this specialization. Here, we focus on two such factors—the Drosophila cephalic gap genes empty spiracles (ems) and orthodenticle (otd), and their vertebrate homologues Emx1/2 and Otx1/2—and review novel insight into their multiple crucial roles in the formation of complex sensory systems. While the early requirement of these genes in specification of the neuroectoderm has been discussed previously, here we consider more recent studies that elucidate the later functions of these genes in sensory system formation in vertebrates and invertebrates. These new studies show that the ems and Emx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective olfactory systems. Moreover, they demonstrate that the otd and Otx genes in both flies and mice are essential for the development of the peripheral and central neurons of their respective visual systems. Based on these recent experimental findings, we discuss the possibility that the olfactory and visual systems of flies and mice share a common evolutionary origin, in that the conserved visual and olfactory circuit elements derive from conserved domains of otd/Otx and ems/Emx action in the urbilaterian ancestor.
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Affiliation(s)
- Sonia Sen
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, UAS-GKVK Campus, Bellary Road, Bangalore 560065, India
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Watanabe S, Sanuki R, Ueno S, Koyasu T, Hasegawa T, Furukawa T. Tropisms of AAV for subretinal delivery to the neonatal mouse retina and its application for in vivo rescue of developmental photoreceptor disorders. PLoS One 2013; 8:e54146. [PMID: 23335994 PMCID: PMC3545928 DOI: 10.1371/journal.pone.0054146] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Accepted: 12/06/2012] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Adeno-associated virus (AAV) is well established as a vehicle for in vivo gene transfer into the mammalian retina. This virus is promising not only for gene therapy of retinal diseases, but also for in vivo functional analysis of retinal genes. Previous reports have shown that AAV can infect various cell types in the developing mouse retina. However, AAV tropism in the developing retina has not yet been examined in detail. METHODOLOGY/PRINCIPAL FINDINGS We subretinally delivered seven AAV serotypes (AAV2/1, 2/2, 2/5, 2/8, 2/9, 2/10, and 2/11) of AAV-CAG-mCherry into P0 mouse retinas, and quantitatively evaluated the tropisms of each serotype by its infecting degree in retinal cells. After subretinal injection of AAV into postnatal day 0 (P0) mouse retinas, various retinal cell types were efficiently transduced with different AAVs. Photoreceptor cells were efficiently transduced with AAV2/5. Retinal cells, except for bipolar and Müller glial cells, were efficiently transduced with AAV2/9. Horizontal and/or ganglion cells were efficiently transduced with AAV2/1, AAV2/2, AAV2/8, AAV2/9 and AAV2/10. To confirm the usefulness of AAV-mediated gene transfer into the P0 mouse retina, we performed AAV-mediated rescue of the Cone-rod homeobox gene knockout (Crx KO) mouse, which exhibits an outer segment formation defect, flat electroretinogram (ERG) responses, and photoreceptor degeneration. We injected an AAV expressing Crx under the control of the Crx 2kb promoter into the neonatal Crx KO retina. We showed that AAV mediated-Crx expression significantly decreased the abnormalities of the Crx KO retina. CONCLUSION/SIGNIFICANCE In the current study, we report suitable AAV tropisms for delivery into the developing mouse retina. Using AAV2/5 in photoreceptor cells, we demonstrated the possibility of gene replacement for the developmental disorder and subsequent degeneration of retinal photoreceptors caused by the absence of Crx.
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Affiliation(s)
- Satoshi Watanabe
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- JST, CREST, Suita, Osaka, Japan
- Department of Developmental Biology, Osaka Bioscience Institute, Suita, Osaka, Japan
- Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto, Kyoto, Japan
| | - Rikako Sanuki
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- JST, CREST, Suita, Osaka, Japan
- Department of Developmental Biology, Osaka Bioscience Institute, Suita, Osaka, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Aichi, Japan
| | - Toshiyuki Koyasu
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Showa-ku, Nagoya, Aichi, Japan
| | - Toshiaki Hasegawa
- Research Center for Ultra-high Voltage Electron Microscopy, Osaka University, Ibaraki, Osaka, Japan
| | - Takahisa Furukawa
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
- JST, CREST, Suita, Osaka, Japan
- Department of Developmental Biology, Osaka Bioscience Institute, Suita, Osaka, Japan
- * E-mail:
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Gregory-Evans CY, Wallace VA, Gregory-Evans K. Gene networks: dissecting pathways in retinal development and disease. Prog Retin Eye Res 2012; 33:40-66. [PMID: 23128416 DOI: 10.1016/j.preteyeres.2012.10.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 10/18/2012] [Accepted: 10/19/2012] [Indexed: 01/21/2023]
Abstract
During retinal neurogenesis, diverse cellular subtypes originate from multipotent neural progenitors in a spatiotemporal order leading to a highly specialized laminar structure combined with a distinct mosaic architecture. This is driven by the combinatorial action of transcription factors and signaling molecules which specify cell fate and differentiation. The emerging approach of gene network analysis has allowed a better understanding of the functional relationships between genes expressed in the developing retina. For instance, these gene networks have identified transcriptional hubs that have revealed potential targets and pathways for the development of therapeutic options for retinal diseases. Much of the current knowledge has been informed by targeted gene deletion experiments and gain-of-functional analysis. In this review we will provide an update on retinal development gene networks and address the wider implications for future disease therapeutics.
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Affiliation(s)
- Cheryl Y Gregory-Evans
- Department of Ophthalmology, University of British Columbia, Vancouver, BC V5Z 3N9, Canada.
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31
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Pang JJ, Lei L, Dai X, Shi W, Liu X, Dinculescu A, McDowell JH. AAV-mediated gene therapy in mouse models of recessive retinal degeneration. Curr Mol Med 2012; 12:316-30. [PMID: 22300136 DOI: 10.2174/156652412799218877] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 08/23/2011] [Accepted: 10/25/2011] [Indexed: 02/01/2023]
Abstract
In recent years, more and more mutant genes that cause retinal diseases have been detected. At the same time, many naturally occurring mouse models of retinal degeneration have also been found, which show similar changes to human retinal diseases. These, together with improved viral vector quality allow more and more traditionally incurable inherited retinal disorders to become potential candidates for gene therapy. Currently, the most common vehicle to deliver the therapeutic gene into target retinal cells is the adenoassociated viral vector (AAV). Following delivery to the immuno-privileged subretinal space, AAV-vectors can efficiently target both retinal pigment epithelium and photoreceptor cells, the origin of most retinal degenerations. This review focuses on the AAV-based gene therapy in mouse models of recessive retinal degenerations, especially those in which delivery of the correct copy of the wild-type gene has led to significant beneficial effects on visual function, as determined by morphological, biochemical, electroretinographic and behavioral analysis. The past studies in animal models and ongoing successful LCA2 clinical trials, predict a bright future for AAV gene replacement treatment for inherited recessive retinal diseases.
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Affiliation(s)
- J-J Pang
- Eye Hospital, School of Ophthalmology & Optometry, Wenzhou Medical College, China.
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Spontaneous activity promotes synapse formation in a cell-type-dependent manner in the developing retina. J Neurosci 2012; 32:5426-39. [PMID: 22514306 DOI: 10.1523/jneurosci.0194-12.2012] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Spontaneous activity is thought to regulate synaptogenesis in many parts of the developing nervous system. In vivo evidence for this regulation, however, is scarce and comes almost exclusively from experiments in which normal activity was reduced or blocked completely. Thus, whether spontaneous activity itself promotes synaptogenesis or plays a purely permissive role remains uncertain. In addition, how activity influences synapse dynamics to shape connectivity and whether its effects among neurons are uniform or cell-type-dependent is unclear. In mice lacking the cone-rod homeobox gene (Crx), photoreceptors fail to establish normal connections with bipolar cells (BCs). Here, we find that retinal ganglion cells (RGCs) in Crx⁻/⁻ mice become rhythmically hyperactive around the time of eye opening as a result of increased spontaneous glutamate release from BCs. This elevated neurotransmission enhances synaptogenesis between BCs and RGCs, without altering the overall circuit architecture. Using live imaging, we discover that spontaneous activity selectively regulates the rate of synapse formation, not elimination, in this circuit. Reconstructions of the connectivity patterns of three BC types with a shared RGC target further revealed that neurotransmission specifically promotes the formation of multisynaptic appositions from one BC type without affecting the maintenance or elimination of connections from the other two. Although hyperactivity in Crx⁻/⁻ mice persists, synapse numbers do not increase beyond 4 weeks of age, suggesting closure of a critical period for synaptic refinement in the inner retina. Interestingly, despite their hyperactivity, RGC axons maintain normal eye-specific territories and cell-type-specific layers in the dorsal lateral geniculate nucleus.
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Ueta T, Inoue T, Yuda K, Furukawa T, Yanagi Y, Tamaki Y. Intense physiological light upregulates vascular endothelial growth factor and enhances choroidal neovascularization via peroxisome proliferator-activated receptor γ coactivator-1α in mice. Arterioscler Thromb Vasc Biol 2012; 32:1366-71. [PMID: 22516064 DOI: 10.1161/atvbaha.112.248021] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Toxicity of intense light to facilitate the development of neovascular age-related macular degeneration has been a health concern although the mechanism remains unclear. METHODS AND RESULTS Effects of intense, but within physiological range, light on retinal pigment epithelium, a major pathogenic origin of age-related macular degeneration were studied in mice. Intense physiological light upregulated vascular endothelial growth factor (VEGF) expression in retinal pigment epithelium, independent of circadian rhythm, which resulted in enhancement of choroidal neovascularization. In rd1/rd1 mice or Crx(-/-) mice that do not possess outer segment structure, light exposure did not induce VEGF, indicating that VEGF upregulation by light depended on increased outer segment phagocytosis by retinal pigment epithelium. In retinal pigment epithelium cells phagocytosing increased amount of outer segment, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) not hypoxia-inducible factor-1α was induced, leading to VEGF upregulation. The VEGF upregulation and choroidal neovascularization enhancement were abrogated in PGC-1α(-/-) mice and estrogen-related receptor-α(-/-) mice, indicating the involvement of PGC-1α/estrogen-related receptor-α pathway. CONCLUSIONS Intense physiological light is involved in choroidal neovascularization through excess outer segment phagocytosis and VEGF upregulation mediated by PGC-1α in vivo.
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Affiliation(s)
- Takashi Ueta
- Department of Ophthalmology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
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Hollingsworth TJ, Gross AK. Defective trafficking of rhodopsin and its role in retinal degenerations. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 293:1-44. [PMID: 22251557 DOI: 10.1016/b978-0-12-394304-0.00006-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Retinitis pigmentosa is a retinal degeneration transmitted by varied modes of inheritance and affects approximately 1 in 4000 individuals. The photoreceptors of the outer retina, as well as the retinal pigmented epithelium which supports the outer retina metabolically and structurally, are the retinal regions most affected by the disorder. In several forms of retinitis pigmentosa, the mislocalization of the rod photoreceptor protein rhodopsin is thought to be a contributing factor underlying the pathophysiology seen in patients. The mutations causing this mislocalization often occur in genes coding proteins involved in ciliary formation, vesicular transport, rod outer segment disc formation, and stability, as well as the rhodopsin protein itself. Often, these mutations result in the most early-onset cases of both recessive and dominant retinitis pigmentosa, and the following presents a discussion of the proteins, their degenerative phenotypes, and possible treatments of the disease.
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Affiliation(s)
- T J Hollingsworth
- Department of Vision Sciences, University of Alabama, Birmingham, Alabama, USA
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Cook T, Zelhof A, Mishra M, Nie J. 800 facets of retinal degeneration. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2011; 100:331-68. [PMID: 21377630 DOI: 10.1016/b978-0-12-384878-9.00008-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In today's world of genomics and large computational analyses, rapid progress has been made in identifying genes associated with human retinal diseases. Nevertheless, before significant advances toward effective therapeutic intervention is made, a clearer understanding of the molecular and cellular role of these gene products in normal and diseased photoreceptor cell biology is required. Given the complexity of the vertebrate retina, these advancements are unlikely to be revealed in isolated human cell lines, but instead, will require the use of numerous model systems. Here, we describe several parallels between vertebrate and invertebrate photoreceptor cell biology that are beginning to emerge and advocate the use of Drosophila melanogaster as a powerful genetic model system for uncovering molecular mechanisms of human retinal pathologies, in particular photoreceptor neurodegeneration.
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Affiliation(s)
- T Cook
- Department of Pediatric Ophthalmology, Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
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Won J, Marín de Evsikova C, Smith RS, Hicks WL, Edwards MM, Longo-Guess C, Li T, Naggert JK, Nishina PM. NPHP4 is necessary for normal photoreceptor ribbon synapse maintenance and outer segment formation, and for sperm development. Hum Mol Genet 2010; 20:482-96. [PMID: 21078623 DOI: 10.1093/hmg/ddq494] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Nephronophthisis (NPHP) is an autosomal recessive kidney disease that is often associated with vision and/or brain defects. To date, 11 genes are known to cause NPHP. The gene products, while structurally unrelated, all localize to cilia or centrosomes. Although mouse models of NPHP are available for 9 of the 11 genes, none has been described for nephronophthisis 4 (Nphp4). Here we report a novel, chemically induced mutant, nmf192, that bears a nonsense mutation in exon 4 of Nphp4. Homozygous mutant Nphp4(nmf192/nmf192) mice do not exhibit renal defects, phenotypes observed in human patients bearing mutations in NPHP4, but they do develop severe photoreceptor degeneration and extinguished rod and cone ERG responses by 9 weeks of age. Photoreceptor outer segments (OS) fail to develop properly, and some OS markers mislocalize to the inner segments and outer nuclear layer in the Nphp4(nmf192/nmf192) mutant retina. Despite NPHP4 localization to the transition zone in the connecting cilia (CC), the CC appear to be normal in structure and ciliary transport function is partially retained. Likewise, synaptic ribbons develop normally but then rapidly degenerate by P14. Finally, Nphp4(nmf192/nmf192) male mutants are sterile and show reduced sperm motility and epididymal sperm counts. Although Nphp4(nmf192/nmf192) mice fail to recapitulate the kidney phenotype of NPHP, they will provide a valuable tool to further elucidate how NPHP4 functions in the retina and male reproductive organs.
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Affiliation(s)
- Jungyeon Won
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME 04609, USA
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Mishra M, Oke A, Lebel C, McDonald EC, Plummer Z, Cook TA, Zelhof AC. Pph13 and orthodenticle define a dual regulatory pathway for photoreceptor cell morphogenesis and function. Development 2010; 137:2895-904. [PMID: 20667913 DOI: 10.1242/dev.051722] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The function and integrity of photoreceptor cells are dependent upon the creation and maintenance of specialized apical structures: membrane discs/outer segments in vertebrates and rhabdomeres in insects. We performed a molecular and morphological comparison of Drosophila Pph13 and orthodenticle (otd) mutants to investigate the transcriptional network controlling the late stages of rhabdomeric photoreceptor cell development and function. Although Otd and Pph13 have been implicated in rhabdomere morphogenesis, we demonstrate that it is necessary to remove both factors to completely eliminate rhabdomere formation. Rhabdomere absence is not the result of degeneration or a failure of initiation, but rather the inability of the apical membrane to transform and elaborate into a rhabdomere. Transcriptional profiling revealed that Pph13 plays an integral role in promoting rhabdomeric photoreceptor cell function. Pph13 regulates Rh2 and Rh6, and other phototransduction genes, demonstrating that Pph13 and Otd control a distinct subset of Rhodopsin-encoding genes in adult visual systems. Bioinformatic, DNA binding and transcriptional reporter assays showed that Pph13 can bind and activate transcription via a perfect Pax6 homeodomain palindromic binding site and the Rhodopsin core sequence I (RCSI) found upstream of Drosophila Rhodopsin genes. In vivo studies indicate that Pph13 is necessary and sufficient to mediate the expression of a multimerized RCSI reporter, a marker of photoreceptor cell specificity previously suggested to be regulated by Pax6. Our studies define a key transcriptional regulatory pathway that is necessary for late Drosophila photoreceptor development and will serve as a basis for better understanding rhabdomeric photoreceptor cell development and function.
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Affiliation(s)
- Monalisa Mishra
- Department of Biology, Indiana University, Bloomington, IN 47405, USA
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Rovsing L, Rath MF, Lund-Andersen C, Klein DC, Møller M. A neuroanatomical and physiological study of the non-image forming visual system of the cone-rod homeobox gene (Crx) knock out mouse. Brain Res 2010; 1343:54-65. [PMID: 20438719 DOI: 10.1016/j.brainres.2010.04.066] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 04/13/2010] [Accepted: 04/14/2010] [Indexed: 11/18/2022]
Abstract
The anatomy and physiology of the non-image forming visual system was investigated in a visually blind cone-rod homeobox gene (Crx) knock-out mouse (Crx(-)(/)(-)), which lacks the outer segments of the photoreceptors. We show that the suprachiasmatic nuclei (SCN) in the Crx(-/-) mouse exhibit morphology as in the wild type mouse. In addition, the SCN contain vasoactive intestinal peptide-, vasopressin-, and gastrin-releasing peptide-immunoreactive neurons as present in the wild type. Anterograde in vivo tracings from the retina of the Crx(-/-) and wild type mouse showed that the retinohypothalamic projection to the SCN and the central optic pathways were similar in both animals. Telemetric monitoring of the running activity and temperature revealed that both the Crx(-/-)and wild type mouse exhibited diurnal rhythms with a 24-h period, which could be phase changed by light. However, power spectral analysis revealed that both rhythms in the Crx(-/-) mouse were less robust than those in the wild type. The normal development of the SCN and the central visual pathways in the Crx(-/-) mouse suggests that a modulatory input from the photoreceptors in the peripheral retina to the retinal melanopsin neurons or the SCN may be necessary for a normal function of the non-image forming system of the mouse. However, a change in the SCN of the Crx(-/-) mouse might also explain the observed circadian differences between the knock out mouse and wild type mouse.
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Affiliation(s)
- Louise Rovsing
- Department of Neuroscience and Pharmacology, Panum Institute, University of Copenhagen, Copenhagen, Denmark
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Goldshmit Y, Galley S, Foo D, Sernagor E, Bourne JA. Anatomical changes in the primary visual cortex of the congenitally blind Crx-/- mouse. Neuroscience 2009; 166:886-98. [PMID: 20034544 DOI: 10.1016/j.neuroscience.2009.12.039] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 12/09/2009] [Accepted: 12/15/2009] [Indexed: 10/20/2022]
Abstract
Mutations in the human cone-rod homeobox (Crx) gene are associated with retinal dystrophies such as Leber Congenital Amaurosis (LCA), characterized by complete or near complete absence of vision from birth. The photoreceptors of Crx-/- mice lack outer segments, and therefore cannot capture light signals through rods and cones, thus resulting in a lack of normal retinal ganglion cell activity from birth. Using specific antibodies to subsets of neurons and markers of activity, we examined the impact of this absence of sensory input on the development of the primary visual cortex (V1) in early postnatal Crx-/- mice, before wiring of the visual system is complete, and in adulthood. We revealed that Crx-/- mice did not exhibit gross anatomical differences in V1; however, they exhibited significantly fewer calcium-binding protein (parvalbumin and calbindin-D28k) expressing interneurons, as well as reduced nonphosphorylated neurofilament expression in V1. These results reveal that the Crx mutation and lack of light stimulation through the photoreceptor pathway regulate the development and phenotype of different neuronal populations in V1 but not its general morphology. We conclude, therefore, that photoreceptor-mediated visual input during development is crucial for the normal postnatal development and maturation of subsets of cortical neurons.
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Affiliation(s)
- Y Goldshmit
- Australian Regenerative Medicine Institute, Monash University, VIC, 3800 Australia
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Won J, Gifford E, Smith RS, Yi H, Ferreira PA, Hicks WL, Li T, Naggert JK, Nishina PM. RPGRIP1 is essential for normal rod photoreceptor outer segment elaboration and morphogenesis. Hum Mol Genet 2009; 18:4329-39. [PMID: 19679561 DOI: 10.1093/hmg/ddp385] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The function of the retinitis pigmentosa GTPase regulator interacting protein 1 (RPGRIP1) gene is currently not known. However, mutations within the gene lead to Leber Congenital Amaurosis and autosomal recessive retinitis pigmentosa in human patients. In a previously described knockout mouse model of the long splice variant of Rpgrip1, herein referred to as Rpgrip1(tm1Tili) mice, mislocalization of key outer segment proteins and dysmorphogenesis of outer segment discs preceded subsequent photoreceptor degeneration. In this report, we describe a new mouse model carrying a splice acceptor site mutation in Rpgrip1, herein referred to as Rpgrip1(nmf247) that is phenotypically distinct from Rpgrip1(tm1Tili) mice. Photoreceptor degeneration in homozygous Rpgrip1(nmf247) mice is earlier in onset and more severe when compared with Rpgrip1(tm1Tili) mice. Also, ultrastructural studies reveal that whereas Rpgrip1(nmf247) mutants have a normal structure and number of connecting cilia, unlike Rpgrip1(tm1Tili) mice, they do not elaborate rod outer segments (OS). Therefore, in addition to its role in OS disc morphogenesis, RPGRIP1 is essential for rod OS formation. Our study indicates the absence of multiple Rpgrip1 isoforms in Rpgrip1(nmf247) mice, suggesting different isoforms may play different roles in photoreceptors and underscores the importance of considering splice variants when generating targeted null mutations.
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Affiliation(s)
- Jungyeon Won
- The Jackson Laboratory, Bar Harbor, ME 04609, USA
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Glubrecht DD, Kim JH, Russell L, Bamforth JS, Godbout R. Differential CRX and OTX2 expression in human retina and retinoblastoma. J Neurochem 2009; 111:250-63. [PMID: 19686387 DOI: 10.1111/j.1471-4159.2009.06322.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The histogenesis of retinoblastoma tumors remains controversial, with the cell-of-origin variably proposed to be an uncommitted retinal progenitor cell, a bipotent committed cell, or a cell committed to a specific lineage. Here, we examine the expression of two members of the orthodenticle family implicated in photoreceptor and bipolar cell differentiation, cone-rod homeobox, CRX, and orthodenticle homeobox 2, OTX2, in normal human retina, retinoblastoma cell lines and retinoblastoma tumors. We show that CRX and OTX2 have distinct expression profiles in the developing human retina, with CRX first expressed in proliferating cells and cells committed to the bipolar lineage, and OTX2 first appearing in the photoreceptor lineage. In the mature retina, CRX levels are highest in photoreceptor cells whereas OTX2 is preferentially found in bipolar cells and in the retinal pigmented epithelium. Both CRX and OTX2 are widely expressed in retinoblastoma cell lines and in retinoblastoma tumors, although CRX is more abundant than OTX2 in the differentiated elements of retinoblastoma tumors such as large rosettes, Flexner-Wintersteiner rosettes and fleurettes. Widespread expression of CRX and OTX2 in retinoblastoma tumors and cell lines suggests a close link between the cell-of-origin of retinoblastoma tumors and cells expressing CRX and OTX2.
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Affiliation(s)
- Darryl D Glubrecht
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada
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Abstract
Ion channels are the gatekeepers to neuronal excitability. Retinal neurons of vertebrates and invertebrates, neurons of the suprachiasmatic nucleus (SCN) of vertebrates, and pinealocytes of non-mammalian vertebrates display daily rhythms in their activities. The interlocking transcription-translation feedback loops with specific post-translational modulations within individual cells form the molecular clock, the basic mechanism that maintains the autonomic approximately 24-h rhythm. The molecular clock regulates downstream output signaling pathways that further modulate activities of various ion channels. Ultimately, it is the circadian regulation of ion channel properties that govern excitability and behavior output of these neurons. In this review, we focus on the recent development of research in circadian neurobiology mainly from 1980 forward. We will emphasize the circadian regulation of various ion channels, including cGMP-gated cation channels, various voltage-gated calcium and potassium channels, Na(+)/K(+)-ATPase, and a long-opening cation channel. The cellular mechanisms underlying the circadian regulation of these ion channels and their functions in various tissues and organisms will also be discussed. Despite the magnitude of chronobiological studies in recent years, the circadian regulation of ion channels still remains largely unexplored. Through more investigation and understanding of the circadian regulation of ion channels, the future development of therapeutic strategies for the treatment of sleep disorders, cardiovascular diseases, and other illnesses linked to circadian misalignment will benefit.
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Affiliation(s)
- Gladys Y-P Ko
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas 77843-4458, USA.
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Wu Y, Wang XF, Mo XA, Sun HB, Li JM, Zeng Y, Lin T, Yuan J, Xi ZQ, Zhu X, Zheng JO. Expression of laminin β1 in hippocampi of patients with intractable epilepsy. Neurosci Lett 2008; 443:160-4. [DOI: 10.1016/j.neulet.2008.07.080] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 07/15/2008] [Accepted: 07/23/2008] [Indexed: 01/25/2023]
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den Hollander AI, Roepman R, Koenekoop RK, Cremers FPM. Leber congenital amaurosis: genes, proteins and disease mechanisms. Prog Retin Eye Res 2008; 27:391-419. [PMID: 18632300 DOI: 10.1016/j.preteyeres.2008.05.003] [Citation(s) in RCA: 556] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Leber congenital amaurosis (LCA) is the most severe retinal dystrophy causing blindness or severe visual impairment before the age of 1 year. Linkage analysis, homozygosity mapping and candidate gene analysis facilitated the identification of 14 genes mutated in patients with LCA and juvenile retinal degeneration, which together explain approximately 70% of the cases. Several of these genes have also been implicated in other non-syndromic or syndromic retinal diseases, such as retinitis pigmentosa and Joubert syndrome, respectively. CEP290 (15%), GUCY2D (12%), and CRB1 (10%) are the most frequently mutated LCA genes; one intronic CEP290 mutation (p.Cys998X) is found in approximately 20% of all LCA patients from north-western Europe, although this frequency is lower in other populations. Despite the large degree of genetic and allelic heterogeneity, it is possible to identify the causative mutations in approximately 55% of LCA patients by employing a microarray-based, allele-specific primer extension analysis of all known DNA variants. The LCA genes encode proteins with a wide variety of retinal functions, such as photoreceptor morphogenesis (CRB1, CRX), phototransduction (AIPL1, GUCY2D), vitamin A cycling (LRAT, RDH12, RPE65), guanine synthesis (IMPDH1), and outer segment phagocytosis (MERTK). Recently, several defects were identified that are likely to affect intra-photoreceptor ciliary transport processes (CEP290, LCA5, RPGRIP1, TULP1). As the eye represents an accessible and immune-privileged organ, it appears to be uniquely suitable for human gene replacement therapy. Rodent (Crb1, Lrat, Mertk, Rpe65, Rpgrip1), avian (Gucy2D) and canine (Rpe65) models for LCA and profound visual impairment have been successfully corrected employing adeno-associated virus or lentivirus-based gene therapy. Moreover, phase 1 clinical trials have been carried out in humans with RPE65 deficiencies. Apart from ethical considerations inherently linked to treating children, major obstacles for the treatment of LCA could be the putative developmental deficiencies in the visual cortex in persons blind from birth (amblyopia), the absence of sufficient numbers of viable photoreceptor or RPE cells in LCA patients, and the unknown and possibly toxic effects of overexpression of transduced genes. Future LCA research will focus on the identification of the remaining causal genes, the elucidation of the molecular mechanisms of disease in the retina, and the development of gene therapy approaches for different genetic subtypes of LCA.
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Affiliation(s)
- Anneke I den Hollander
- Department of Human Genetics & Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
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Onorati M, Cremisi F, Liu Y, He RQ, Barsacchi G, Vignali R. A specific box switches the cell fate determining activity of XOTX2 and XOTX5b in the Xenopus retina. Neural Dev 2007; 2:12. [PMID: 17597530 PMCID: PMC1929070 DOI: 10.1186/1749-8104-2-12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2006] [Accepted: 06/27/2007] [Indexed: 11/27/2022] Open
Abstract
Background Otx genes, orthologues of the Drosophila orthodenticle gene (otd), play crucial roles in vertebrate brain development. In the Xenopus eye, Xotx2 and Xotx5b promote bipolar and photoreceptor cell fates, respectively. The molecular basis of their differential action is not completely understood, though the carboxyl termini of the two proteins seem to be crucial. To define the molecular domains that make the action of these proteins so different, and to determine whether their retinal abilities are shared by Drosophila OTD, we performed an in vivo molecular dissection of their activity by transfecting retinal progenitors with several wild-type, deletion and chimeric constructs of Xotx2, Xotx5b and otd. Results We identified a small 8–10 amino acid divergent region, directly downstream of the homeodomain, that is crucial for the respective activities of XOTX2 and XOTX5b. In lipofection experiments, the exchange of this 'specificity box' completely switches the retinal activity of XOTX5b into that of XOTX2 and vice versa. Moreover, the insertion of this box into Drosophila OTD, which has no effect on retinal cell fate, endows it with the specific activity of either XOTX protein. Significantly, in cell transfection experiments, the diverse ability of XOTX2 and XOTX5b to synergize with NRL, a cofactor essential for vertebrate rod development, to transactivate the rhodopsin promoter is also switched depending on the box. We also show by GST-pull down that XOTX2 and XOTX5b differentially interact with NRL, though this property is not strictly dependent on the box. Conclusion Our data provide molecular evidence on how closely related homeodomain gene products can differentiate their functions to regulate distinct cell fates. A small 'specificity box' is both necessary and sufficient to confer on XOTX2 and XOTX5b their distinct activities in the developing frog retina and to convert the neutral orthologous OTD protein of Drosophila into a positive and specific XOTX-like retinal regulator. Relatively little is known of what gives developmental specificity to homeodomain regulators. We propose that this box is a major domain of XOTX proteins that provides them with the appropriate developmental specificity in retinal histogenesis.
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Affiliation(s)
- Marco Onorati
- Dipartimento di Biologia, Unità di Biologia Cellulare e dello Sviluppo, Università di Pisa, Via G. Carducci 13, 56010 Ghezzano (Pisa), Italy
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56100 Pisa, Italy
| | - Federico Cremisi
- Dipartimento di Biologia, Unità di Biologia Cellulare e dello Sviluppo, Università di Pisa, Via G. Carducci 13, 56010 Ghezzano (Pisa), Italy
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56100 Pisa, Italy
| | - Yang Liu
- State Key Lab of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Da Tun Road, Chao Yang District, Beijing 100101, China RP
- Dana-Farber Cancer Institute, Jimmy Fund Way, Boston, MA 02115, USA
| | - Rong-Qiao He
- State Key Lab of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Da Tun Road, Chao Yang District, Beijing 100101, China RP
| | - Giuseppina Barsacchi
- Dipartimento di Biologia, Unità di Biologia Cellulare e dello Sviluppo, Università di Pisa, Via G. Carducci 13, 56010 Ghezzano (Pisa), Italy
- AMBISEN Center, High Technology Center for the Study of the Environmental Damage of the Endocrine and Nervous System, Università di Pisa, Pisa, Italy
| | - Robert Vignali
- Dipartimento di Biologia, Unità di Biologia Cellulare e dello Sviluppo, Università di Pisa, Via G. Carducci 13, 56010 Ghezzano (Pisa), Italy
- AMBISEN Center, High Technology Center for the Study of the Environmental Damage of the Endocrine and Nervous System, Università di Pisa, Pisa, Italy
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Hadley D, Murphy T, Valladares O, Hannenhalli S, Ungar L, Kim J, Bućan M. Patterns of sequence conservation in presynaptic neural genes. Genome Biol 2007; 7:R105. [PMID: 17096848 PMCID: PMC1794582 DOI: 10.1186/gb-2006-7-11-r105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Revised: 09/25/2006] [Accepted: 11/10/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The neuronal synapse is a fundamental functional unit in the central nervous system of animals. Because synaptic function is evolutionarily conserved, we reasoned that functional sequences of genes and related genomic elements known to play important roles in neurotransmitter release would also be conserved. RESULTS Evolutionary rate analysis revealed that presynaptic proteins evolve slowly, although some members of large gene families exhibit accelerated evolutionary rates relative to other family members. Comparative sequence analysis of 46 megabases spanning 150 presynaptic genes identified more than 26,000 elements that are highly conserved in eight vertebrate species, as well as a small subset of sequences (6%) that are shared among unrelated presynaptic genes. Analysis of large gene families revealed that upstream and intronic regions of closely related family members are extremely divergent. We also identified 504 exceptionally long conserved elements (> or =360 base pairs, > or =80% pair-wise identity between human and other mammals) in intergenic and intronic regions of presynaptic genes. Many of these elements form a highly stable stem-loop RNA structure and consequently are candidates for novel regulatory elements, whereas some conserved noncoding elements are shown to correlate with specific gene expression profiles. The SynapseDB online database integrates these findings and other functional genomic resources for synaptic genes. CONCLUSION Highly conserved elements in nonprotein coding regions of 150 presynaptic genes represent sequences that may be involved in the transcriptional or post-transcriptional regulation of these genes. Furthermore, comparative sequence analysis will facilitate selection of genes and noncoding sequences for future functional studies and analysis of variation studies in neurodevelopmental and psychiatric disorders.
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Affiliation(s)
- Dexter Hadley
- Penn Center for Bioinformatics, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Genomics and Computational Biology Graduate Group, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Tara Murphy
- Department of Genetics in the School of Medicine, University of Pennsylvania, 415 Curie Boulevard Philadelphia, Pennsylvania 19104, USA
- UCLA Neuroscience Graduate Office, 695 Young Drive South, Los Angeles, California 90095, USA
| | - Otto Valladares
- Department of Genetics in the School of Medicine, University of Pennsylvania, 415 Curie Boulevard Philadelphia, Pennsylvania 19104, USA
| | - Sridhar Hannenhalli
- Penn Center for Bioinformatics, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Genomics and Computational Biology Graduate Group, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Lyle Ungar
- Penn Center for Bioinformatics, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Computer & Information Sciences in School of Engineering and Applied Sciences, 3330 Walnut Street, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Junhyong Kim
- Penn Center for Bioinformatics, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Computer & Information Sciences in School of Engineering and Applied Sciences, 3330 Walnut Street, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Biology in the School of Arts and Sciences, 433 S University Avenue, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Maja Bućan
- Penn Center for Bioinformatics, 423 Guardian Drive, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
- Department of Genetics in the School of Medicine, University of Pennsylvania, 415 Curie Boulevard Philadelphia, Pennsylvania 19104, USA
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Johnson DA, Donovan SL, Dyer MA. Mosaic deletion of Rb arrests rod differentiation and stimulates ectopic synaptogenesis in the mouse retina. J Comp Neurol 2006; 498:112-28. [PMID: 16856163 DOI: 10.1002/cne.21059] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The retinoblastoma gene (Rb) regulates neural progenitor cell proliferation and cell fate specification and differentiation. For the developing mouse retina, two distinct functions of Rb have been described: regulation of retinal progenitor cell proliferation and rod photoreceptor development. Cells that would normally become rods fail to mature and remain as immature cells in the outer nuclear layer in the adult. By using Chx10-Cre;Rb(Lox/-) mice, we generated a chimeric retina with alternating apical-basal stripes of wild-type and Rb-deficient tissue. This provides a unique model with which to study synaptogenesis at the outer plexiform layer within regions that lack differentiated rods. In regions where rods failed to differentiate, the outer plexiform layer (OPL) was disrupted. Horizontal cells formed, and their somata were appropriately aligned, but their neurites did not project laterally. Instead many horizonal cell neurites extended apically, forming ectopic synapses with photoreceptors at all levels of the outer nuclear layer. These ectopic photoreceptor terminals contained synaptic ribbons, horizontal cell processes with synaptic vesicles, and a single mitochrondrion characteristic of rod spherules. Rb-deficient bipolar cells differentiated normally, extended dendrites to the OPL, and formed synapses that were indistinguishable from adjacent wild-type cells. In contrast to OPL-positioned synapses, ectopic synapses did not contain bipolar dendrites. This finding suggests that horizontal cells and photoreceptors can form stable synapses that are devoid of bipolar dendrites outside the normal boundaries of the OPL. Finally, analysis of P4, P7, P12, and P15 retinae suggests that the apical horizontal cell processes result from their failure to establish their normal lateral projections during development.
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Affiliation(s)
- Dianna A Johnson
- Department of Ophthalmology, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee 38105, USA
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Srinivas M, Ng L, Liu H, Jia L, Forrest D. Activation of the Blue Opsin Gene in Cone Photoreceptor Development by Retinoid-Related Orphan Receptor β. Mol Endocrinol 2006; 20:1728-41. [PMID: 16574740 DOI: 10.1210/me.2005-0505] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
AbstractColor vision requires the expression of opsin photopigments with different wavelength sensitivities in retinal cone photoreceptors. The basic color visual system of mammals is dichromatic, involving differential expression in the cone population of two opsins with sensitivity to short (S, blue) or medium (M, green) wavelengths. However, little is known of the factors that directly activate these opsin genes and thereby contribute to the S or M opsin identity of the cone. We report that the orphan nuclear receptor RORβ (retinoid-related orphan receptor β) activates the S opsin gene (Opn1sw) through binding sites upstream of the gene. RORβ lacks a known physiological ligand and activates the Opn1sw promoter modestly alone but strongly in synergy with the retinal cone-rod homeobox factor (CRX), suggesting a cooperative means of enhancing RORβ activity. Comparison of wild-type and mutant lacZ reporter transgenes showed that the RORβ-binding sites in Opn1sw are required for expression in mouse retina. RORβ-deficient mice fail to induce S opsin appropriately during postnatal cone development. Photoreceptors in these mice also lack outer segments, indicating additional functions for RORβ in photoreceptor morphological maturation. The results identify Opn1sw as a target gene for RORβ and suggest a key role for RORβ in regulating opsin expression in the color visual system.
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Affiliation(s)
- Maya Srinivas
- Department of Human Genetics, Mount Sinai School of Medicine, New York, New York 10029, USA
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Michaelides M, Hardcastle AJ, Hunt DM, Moore AT. Progressive cone and cone-rod dystrophies: phenotypes and underlying molecular genetic basis. Surv Ophthalmol 2006; 51:232-58. [PMID: 16644365 DOI: 10.1016/j.survophthal.2006.02.007] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The cone and cone-rod dystrophies form part of a heterogeneous group of retinal disorders that are an important cause of visual impairment in children and adults. There have been considerable advances made in recent years in our understanding of the pathogenesis of these retinal dystrophies, with many of the chromosomal loci and causative genes having now been identified. Mutations in 12 genes, including GUCA1A, peripherin/RDS, ABCA4 and RPGR, have been described to date; and in many cases detailed functional assessment of the effects of the encoded mutant proteins has been undertaken. This improved knowledge of disease mechanisms has raised the possibility of future treatments for these disorders, for which there are no specific therapies available at the present time.
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Inoue T, Terada K, Furukawa A, Koike C, Tamaki Y, Araie M, Furukawa T. Cloning and characterization of mr-s, a novel SAM domain protein, predominantly expressed in retinal photoreceptor cells. BMC DEVELOPMENTAL BIOLOGY 2006; 6:15. [PMID: 16539743 PMCID: PMC1435744 DOI: 10.1186/1471-213x-6-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Accepted: 03/16/2006] [Indexed: 11/17/2022]
Abstract
Background Sterile alpha motif (SAM) domains are ~70 residues long and have been reported as common protein-protein interaction modules. This domain is found in a large number of proteins, including Polycomb group (PcG) proteins and ETS family transcription factors. In this work, we report the cloning and functional characterization of a novel SAM domain-containing protein, which is predominantly expressed in retinal photoreceptors and the pineal gland and is designated mouse mr-s (major retinal SAM domain protein). Results mr-s is evolutionarily conserved from zebrafish through human, organisms through which the mechanism of photoreceptor development is also highly conserved. Phylogenetic analysis suggests that the SAM domain of mr-s is most closely related to a mouse polyhomeotic (ph) ortholog, Mph1/Rae28, which is known as an epigenetic molecule involved in chromatin modifications. These findings provide the possibility that mr-s may play a critical role by regulating gene expression in photoreceptor development. mr-s is preferentially expressed in the photoreceptors at postnatal day 3–6 (P3-6), when photoreceptors undergo terminal differentiation, and in the adult pineal gland. Transcription of mr-s is directly regulated by the cone-rod homeodomain protein Crx. Immunoprecipitation assay showed that the mr-s protein self-associates mainly through the SAM domain-containing region as well as ph. The mr-s protein localizes mainly in the nucleus, when mr-s is overexpressed in HEK293T cells. Moreover, in the luciferase assays, we found that mr-s protein fused to GAL4 DNA-binding domain functions as a transcriptional repressor. We revealed that the repression activity of mr-s is not due to a homophilic interaction through its SAM domain but to the C-terminal region. Conclusion We identified a novel gene, mr-s, which is predominantly expressed in retinal photoreceptors and pineal gland. Based on its expression pattern and biochemical analysis, we predict that mr-s may function as a transcriptional repressor in photoreceptor cells and in pinealocytes of the pineal gland.
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Affiliation(s)
- Tatsuya Inoue
- Osaka Bioscience Institute; 6-2-4 Furuedai, Suita, Osaka 565-0874, Japan
- PRESTO, Japan Science and Technology Agency; 4-1-8 Honcho, Kawaguchi, Saitama, Japan
- Department of Ophthalmology, Tokyo University School of Medicine; 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Koji Terada
- Osaka Bioscience Institute; 6-2-4 Furuedai, Suita, Osaka 565-0874, Japan
| | - Akiko Furukawa
- Osaka Bioscience Institute; 6-2-4 Furuedai, Suita, Osaka 565-0874, Japan
- Department of Ophthalmology, Osaka University Medical School; Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Chieko Koike
- Osaka Bioscience Institute; 6-2-4 Furuedai, Suita, Osaka 565-0874, Japan
| | - Yasuhiro Tamaki
- Department of Ophthalmology, Tokyo University School of Medicine; 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Makoto Araie
- Department of Ophthalmology, Tokyo University School of Medicine; 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Takahisa Furukawa
- Osaka Bioscience Institute; 6-2-4 Furuedai, Suita, Osaka 565-0874, Japan
- PRESTO, Japan Science and Technology Agency; 4-1-8 Honcho, Kawaguchi, Saitama, Japan
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