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McNamee SM, Akula M, Love Z, Nasraty N, Nystuen K, Singh P, Upadhyay AK, DeAngelis MM, Haider NB. Evaluating therapeutic potential of NR2E3 doses in the rd7 mouse model of retinal degeneration. Sci Rep 2024; 14:16490. [PMID: 39019967 PMCID: PMC11254931 DOI: 10.1038/s41598-024-67095-6] [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: 03/25/2024] [Accepted: 07/08/2024] [Indexed: 07/19/2024] Open
Abstract
Retinitis Pigmentosa is a leading cause of severe vision loss. Retinitis Pigmentosa can present with a broad range of phenotypes impacted by disease age of onset, severity, and progression. This variation is influenced both by different gene mutations as well as unique variants within the same gene. Mutations in the nuclear hormone receptor 2 family e, member 3 are associated with several forms of retinal degeneration, including Retinitis Pigmentosa. In our previous studies we demonstrated that subretinal administration of one Nr2e3 dose attenuated retinal degeneration in rd7 mice for at least 3 months. Here we expand the studies to evaluate the efficacy and longitudinal impact of the NR2E3 therapeutic by examining three different doses administered at early or intermediate stages of retinal degeneration in the rd7 mice. Our study revealed retinal morphology was significantly improved 6 months post for all doses in the early-stage treatment groups and for the low and mid doses in the intermediate stage treatment groups. Similarly, photoreceptor function was significantly improved in the early stage for all doses and intermediate stage low and mid dose groups 6 months post treatment. This study demonstrated efficacy in multiple doses of NR2E3 therapy.
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Affiliation(s)
- Shannon M McNamee
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA
| | - Monica Akula
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA
| | - Zoe Love
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA
| | - Neelaab Nasraty
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA
| | - Kaden Nystuen
- University of Massachusetts Amherst, Amherst, MA, USA
| | | | | | - Margaret M DeAngelis
- Department of Ophthalmology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Neena B Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA.
- Department of Cell Biology, Harvard Medical School, Boston, MA, 02138, USA.
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2
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Aísa-Marín I, Rovira Q, Díaz N, Calvo-López L, Vaquerizas JM, Marfany G. Specific photoreceptor cell fate pathways are differentially altered in NR2E3-associated diseases. Neurobiol Dis 2024; 194:106463. [PMID: 38485095 DOI: 10.1016/j.nbd.2024.106463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/01/2024] [Accepted: 03/02/2024] [Indexed: 03/21/2024] Open
Abstract
Mutations in NR2E3, a gene encoding an orphan nuclear transcription factor, cause two retinal dystrophies with a distinct phenotype, but the precise role of NR2E3 in rod and cone transcriptional networks remains unclear. To dissect NR2E3 function, we performed scRNA-seq in the retinas of wildtype and two different Nr2e3 mouse models that show phenotypes similar to patients carrying NR2E3 mutations. Our results reveal that rod and cone populations are not homogeneous and can be separated into different sub-classes. We identify a previously unreported cone pathway that generates hybrid cones co-expressing both cone- and rod-related genes. In mutant retinas, this hybrid cone subpopulation is more abundant and includes a subpopulation of rods transitioning towards a cone cell fate. Hybrid photoreceptors with high misexpression of cone- and rod-related genes are prone to regulated necrosis. Overall, our results shed light on the role of NR2E3 in modulating photoreceptor differentiation towards cone and rod fates and explain how different mutations in NR2E3 lead to distinct visual disorders in humans.
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Affiliation(s)
- Izarbe Aísa-Marín
- Department de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona 08028, Spain; IBUB-IRSJD, Institut de Biomedicina de la Universitat de Barcelona-Institut de Recerca Sant Joan de Déu, Barcelona 08028, Spain; CIBERER, Instituto de Salud Carlos III, Barcelona 08028, Spain
| | - Quirze Rovira
- Max-Planck-Institute for Molecular Biomedicine, Münster 48149, Germany
| | - Noelia Díaz
- Max-Planck-Institute for Molecular Biomedicine, Münster 48149, Germany
| | - Laura Calvo-López
- Department de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona 08028, Spain
| | - Juan M Vaquerizas
- Max-Planck-Institute for Molecular Biomedicine, Münster 48149, Germany; MRC London Institute of Medical Sciences, Institute of Clinical Sciences, Imperial College London, London W12 0NN, UK.; Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, Du Cane Road, London W12 0NN, UK.
| | - Gemma Marfany
- Department de Genètica, Microbiologia i Estadística, Universitat de Barcelona, Barcelona 08028, Spain; IBUB-IRSJD, Institut de Biomedicina de la Universitat de Barcelona-Institut de Recerca Sant Joan de Déu, Barcelona 08028, Spain; CIBERER, Instituto de Salud Carlos III, Barcelona 08028, Spain; DBGen Ocular Genomics, Barcelona 08028, Spain.
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3
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Corradetti G, Verma A, Tojjar J, Almidani L, Oncel D, Emamverdi M, Bradley A, Lindenberg S, Nittala MG, Sadda SR. Retinal Imaging Findings in Inherited Retinal Diseases. J Clin Med 2024; 13:2079. [PMID: 38610844 PMCID: PMC11012835 DOI: 10.3390/jcm13072079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/19/2024] [Accepted: 03/27/2024] [Indexed: 04/14/2024] Open
Abstract
Inherited retinal diseases (IRDs) represent one of the major causes of progressive and irreversible vision loss in the working-age population. Over the last few decades, advances in retinal imaging have allowed for an improvement in the phenotypic characterization of this group of diseases and have facilitated phenotype-to-genotype correlation studies. As a result, the number of clinical trials targeting IRDs has steadily increased, and commensurate to this, the need for novel reproducible outcome measures and endpoints has grown. This review aims to summarize and describe the clinical presentation, characteristic imaging findings, and imaging endpoint measures that are being used in clinical research on IRDs. For the purpose of this review, IRDs have been divided into four categories: (1) panretinal pigmentary retinopathies affecting rods or cones; (2) macular dystrophies; (3) stationary conditions; (4) hereditary vitreoretinopathies.
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Affiliation(s)
- Giulia Corradetti
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Aditya Verma
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY 40202, USA
| | - Jasaman Tojjar
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Louay Almidani
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Deniz Oncel
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
- Stritch School of Medicine, Loyola University Chicago, Chicago, IL 60153, USA
| | - Mehdi Emamverdi
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
| | - Alec Bradley
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY 40202, USA
| | | | | | - SriniVas R. Sadda
- Doheny Eye Institute, Pasadena, CA 91103, USA (J.T.); (L.A.)
- Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
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4
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Toms M, Ward N, Moosajee M. Nuclear Receptor Subfamily 2 Group E Member 3 (NR2E3): Role in Retinal Development and Disease. Genes (Basel) 2023; 14:1325. [PMID: 37510230 PMCID: PMC10379133 DOI: 10.3390/genes14071325] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/11/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023] Open
Abstract
NR2E3 is a nuclear hormone receptor gene required for the correct development of the retinal rod photoreceptors. Expression of NR2E3 protein in rod cell precursors suppresses cone-specific gene expression and, in concert with other transcription factors including NRL, activates the expression of rod-specific genes. Pathogenic variants involving NR2E3 cause a spectrum of retinopathies, including enhanced S-cone syndrome, Goldmann-Favre syndrome, retinitis pigmentosa, and clumped pigmentary retinal degeneration, with limited evidence of genotype-phenotype correlations. A common feature of NR2E3-related disease is an abnormally high number of cone photoreceptors that are sensitive to short wavelength light, the S-cones. This characteristic has been supported by mouse studies, which have also revealed that loss of Nr2e3 function causes photoreceptors to develop as cells that are intermediate between rods and cones. While there is currently no available cure for NR2E3-related retinopathies, there are a number of emerging therapeutic strategies under investigation, including the use of viral gene therapy and gene editing, that have shown promise for the future treatment of patients with NR2E3 variants and other inherited retinal diseases. This review provides a detailed overview of the current understanding of the role of NR2E3 in normal development and disease, and the associated clinical phenotypes, animal models, and therapeutic studies.
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Affiliation(s)
- Maria Toms
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK
| | - Natasha Ward
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Mariya Moosajee
- Development, Ageing and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK
- Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK
- Department of Genetics, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
- Department of Ophthalmology, Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK
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5
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Gopalakrishnan P, Beryozkin A, Banin E, Sharon D. Morphological and Functional Comparison of Mice Models for Retinitis Pigmentosa. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:365-370. [PMID: 37440058 DOI: 10.1007/978-3-031-27681-1_53] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Retinitis pigmentosa (RP) is the predominant form of inherited retinal degenerations (IRDs) caused by abnormalities and loss of photoreceptor cells ensuing diminishment of vision. RP is a heterogenous genetic disorder associated with mutations in over 80 genes, showing various inheritance patterns. Laboratory mouse models are important for our understanding of disease mechanisms, modifier effects, and development of therapeutic modalities. In this review, we have summarized a comprehensive comparison of our previously reported Fam161a knockout (KO) mouse model with other well-studied RP mouse models, Fam161aGT/GT, Pde6brd1, Nr2e3rd7, Rpgrrd9, and Pde6brd10 using structural and functional analysis of the retina. Fam161atm1b/tm1b mouse models are important for developing novel therapies and mainly AAV-based gene therapy and translational read-through-inducing drugs.
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Affiliation(s)
- Prakadeeswari Gopalakrishnan
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Avigail Beryozkin
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Eyal Banin
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Dror Sharon
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
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6
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Liu F, Qin Y, Huang Y, Gao P, Li J, Yu S, Jia D, Chen X, Lv Y, Tu J, Sun K, Han Y, Reilly J, Shu X, Lu Q, Tang Z, Xu C, Luo D, Liu M. Rod genesis driven by mafba in an nrl knockout zebrafish model with altered photoreceptor composition and progressive retinal degeneration. PLoS Genet 2022; 18:e1009841. [PMID: 35245286 PMCID: PMC8926279 DOI: 10.1371/journal.pgen.1009841] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 03/16/2022] [Accepted: 02/17/2022] [Indexed: 12/25/2022] Open
Abstract
Neural retina leucine zipper (NRL) is an essential gene for the fate determination and differentiation of the precursor cells into rod photoreceptors in mammals. Mutations in NRL are associated with the autosomal recessive enhanced S-cone syndrome and autosomal dominant retinitis pigmentosa. However, the exact role of Nrl in regulating the development and maintenance of photoreceptors in the zebrafish (Danio rerio), a popular animal model used for retinal degeneration and regeneration studies, has not been fully determined. In this study, we generated an nrl knockout zebrafish model via the CRISPR-Cas9 technology and observed a surprising phenotype characterized by a reduced number, but not the total loss, of rods and over-growth of green cones. We discovered two waves of rod genesis, nrl-dependent and -independent at the embryonic and post-embryonic stages, respectively, in zebrafish by monitoring the rod development. Through bulk and single-cell RNA sequencing, we characterized the gene expression profiles of the whole retina and each retinal cell type from the wild type and nrl knockout zebrafish. The over-growth of green cones and mis-expression of green-cone-specific genes in rods in nrl mutants suggested that there are rod/green-cone bipotent precursors, whose fate choice between rod versus green-cone is controlled by nrl. Besides, we identified the mafba gene as a novel regulator of the nrl-independent rod development, based on the cell-type-specific expression patterns and the retinal phenotype of nrl/mafba double-knockout zebrafish. Gene collinearity analysis revealed the evolutionary origin of mafba and suggested that the function of mafba in rod development is specific to modern fishes. Furthermore, the altered photoreceptor composition and abnormal gene expression in nrl mutants caused progressive retinal degeneration and subsequent regeneration. Accordingly, this study revealed a novel function of the mafba gene in rod development and established a working model for the developmental and regulatory mechanisms regarding the rod and green-cone photoreceptors in zebrafish. Vision is mediated by two types of light-sensing cells named rod and cone photoreceptors in animal eyes. Abnormal generation, dysfunction or death of photoreceptor cells all cause irreversible vision problems. NRL is an essential gene for the generation and function of rod cells in mice and humans. Surprisingly, we found that in the zebrafish, a popular animal model for human diseases and therapeutic testing, there are two types of rod cells, and eliminating the function of nrl gene affects the rod cell formation at the embryonic stage but not at the juvenile and adult stages. The rod cell formation at the post-embryonic is driven by the mafba gene, which has not been reported to play a role in rod cells. In addition to the reduced number of rod cells, deletion of nrl also results in the emergence of rod/green-cone hybrid cells and an increased number of green cones. The ensuing cellular and molecular alterations collectively lead to retinal degeneration. These findings expand our understanding of photoreceptor development and maintenance and highlight the underlying conserved and species-specific regulatory mechanisms.
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Affiliation(s)
- Fei Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Innovative Academy of Seed Design, Hubei Hongshan Laboratory, Chinese Academy of Sciences, Wuhan, P.R. China
- University of Chinese Academy of Sciences, Beijing, China
| | - Yayun Qin
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
- Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Yuwen Huang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Pan Gao
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Jingzhen Li
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Shanshan Yu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Danna Jia
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Xiang Chen
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Yuexia Lv
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Jiayi Tu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Kui Sun
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Yunqiao Han
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - James Reilly
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, United Kingdom
| | - Xinhua Shu
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, United Kingdom
| | - Qunwei Lu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Zhaohui Tang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Chengqi Xu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
- * E-mail: (CX); (DL); (ML)
| | - Daji Luo
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Innovative Academy of Seed Design, Hubei Hongshan Laboratory, Chinese Academy of Sciences, Wuhan, P.R. China
- University of Chinese Academy of Sciences, Beijing, China
- * E-mail: (CX); (DL); (ML)
| | - Mugen Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P.R. China
- * E-mail: (CX); (DL); (ML)
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7
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Bery A, Bagchi U, Bergen AA, Felder-Schmittbuhl MP. Circadian clocks, retinogenesis and ocular health in vertebrates: new molecular insights. Dev Biol 2022; 484:40-56. [DOI: 10.1016/j.ydbio.2022.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/21/2022] [Accepted: 02/01/2022] [Indexed: 12/22/2022]
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Ogawa Y, Shiraki T, Fukada Y, Kojima D. Foxq2 determines blue cone identity in zebrafish. SCIENCE ADVANCES 2021; 7:eabi9784. [PMID: 34613771 PMCID: PMC8494292 DOI: 10.1126/sciadv.abi9784] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/13/2021] [Indexed: 05/26/2023]
Abstract
Most vertebrate lineages retain a tetrachromatic visual system, which is supported by a functional combination of spectrally distinct multiple cone photoreceptors, ultraviolet (UV), blue, green, and red cones. The blue cone identity is ensured by selective expression of blue (sws2) opsin, and the mechanism is poorly understood because sws2 gene has been lost in mammalian species such as mouse, whose visual system has been extensively studied. Here, we pursued loss-of-function studies on transcription factors expressed predominantly in zebrafish cone photoreceptors and identified Foxq2 as a blue cone–specific factor driving sws2 gene expression. Foxq2 has dual functions acting as an activator of sws2 transcription and as a suppressor of UV (sws1) opsin transcription in blue cones. A wide range of vertebrate species retain both foxq2 and sws2 genes. We propose that Foxq2-dependent sws2 expression is a prevalent regulatory mechanism that was acquired at the early stage of vertebrate evolution.
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Venturini G, Kokona D, Steiner BL, Bulla EG, Jovanovic J, Zinkernagel MS, Escher P. In vivo analysis of onset and progression of retinal degeneration in the Nr2e3 rd7/rd7 mouse model of enhanced S-cone sensitivity syndrome. Sci Rep 2021; 11:19032. [PMID: 34561487 PMCID: PMC8463594 DOI: 10.1038/s41598-021-98271-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 09/06/2021] [Indexed: 12/02/2022] Open
Abstract
The photoreceptor-specific nuclear receptor Nr2e3 is not expressed in Nr2e3rd7/rd7 mice, a mouse model of the recessively inherited retinal degeneration enhanced S-cone sensitivity syndrome (ESCS). We characterized in detail C57BL/6J Nr2e3rd7/rd7 mice in vivo by fundus photography, optical coherence tomography and fluorescein angiography and, post mortem, by histology and immunohistochemistry. White retinal spots and so-called 'rosettes' first appear at postnatal day (P) 12 in the dorsal retina and reach maximal expansion at P21. The highest density in 'rosettes' is observed within a region located between 100 and 350 µM from the optic nerve head. 'Rosettes' disappear between 9 to 12 months. Non-apoptotic cell death markers are detected during the slow photoreceptor degeneration, at a rate of an approximately 3% reduction of outer nuclear layer thickness per month, as observed from 7 to 31 months of age. In vivo analysis of Nr2e3rd7/rd7 Cx3cr1gfp/+ retinas identified microglial cells within 'rosettes' from P21 on. Subretinal macrophages were observed in vivo and by confocal microscopy earliest in 12-months-old Nr2e3rd7/rd7 retinas. At P21, S-opsin expression and the number of S-opsin expressing dorsal cones was increased. The dorso-ventral M-cone gradient was present in Nr2e3rd7/rd7 retinas, but M-opsin expression and M-opsin expressing cones were decreased. Retinal vasculature was normal.
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Affiliation(s)
- Giulia Venturini
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Despina Kokona
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Beatrice L Steiner
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Emanuele G Bulla
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Joel Jovanovic
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Martin S Zinkernagel
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland
- Department of BioMedical Research, University of Bern, Bern, Switzerland
| | - Pascal Escher
- Department of Ophthalmology, Inselspital, Bern University Hospital, Bern, Switzerland.
- Department of BioMedical Research, University of Bern, Bern, Switzerland.
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10
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Retinal Organoid Technology: Where Are We Now? Int J Mol Sci 2021; 22:ijms221910244. [PMID: 34638582 PMCID: PMC8549701 DOI: 10.3390/ijms221910244] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 09/17/2021] [Accepted: 09/20/2021] [Indexed: 12/25/2022] Open
Abstract
It is difficult to regenerate mammalian retinal cells once the adult retina is damaged, and current clinical approaches to retinal damages are very limited. The introduction of the retinal organoid technique empowers researchers to study the molecular mechanisms controlling retinal development, explore the pathogenesis of retinal diseases, develop novel treatment options, and pursue cell/tissue transplantation under a certain genetic background. Here, we revisit the historical background of retinal organoid technology, categorize current methods of organoid induction, and outline the obstacles and potential solutions to next-generation retinal organoids. Meanwhile, we recapitulate recent research progress in cell/tissue transplantation to treat retinal diseases, and discuss the pros and cons of transplanting single-cell suspension versus retinal organoid sheet for cell therapies.
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11
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Li S, Datta S, Brabbit E, Love Z, Woytowicz V, Flattery K, Capri J, Yao K, Wu S, Imboden M, Upadhyay A, Arumugham R, Thoreson WB, DeAngelis MM, Haider NB. Nr2e3 is a genetic modifier that rescues retinal degeneration and promotes homeostasis in multiple models of retinitis pigmentosa. Gene Ther 2021; 28:223-241. [PMID: 32123325 PMCID: PMC7483267 DOI: 10.1038/s41434-020-0134-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 02/05/2020] [Accepted: 02/18/2020] [Indexed: 12/21/2022]
Abstract
Recent advances in viral vector engineering, as well as an increased understanding of the cellular and molecular mechanism of retinal diseases, have led to the development of novel gene therapy approaches. Furthermore, ease of accessibility and ocular immune privilege makes the retina an ideal target for gene therapies. In this study, the nuclear hormone receptor gene Nr2e3 was evaluated for efficacy as broad-spectrum therapy to attenuate early to intermediate stages of retinal degeneration in five unique mouse models of retinitis pigmentosa (RP). RP is a group of heterogenic inherited retinal diseases associated with over 150 gene mutations, affecting over 1.5 million individuals worldwide. RP varies in age of onset, severity, and rate of progression. In addition, ~40% of RP patients cannot be genetically diagnosed, confounding the ability to develop personalized RP therapies. Remarkably, Nr2e3 administered therapy resulted in reduced retinal degeneration as observed by increase in photoreceptor cells, improved electroretinogram, and a dramatic molecular reset of key transcription factors and associated gene networks. These therapeutic effects improved retinal homeostasis in diseased tissue. Results of this study provide evidence that Nr2e3 can serve as a broad-spectrum therapy to treat multiple forms of RP.
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Affiliation(s)
- Sujun Li
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Shyamtanu Datta
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Emily Brabbit
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Zoe Love
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Victoria Woytowicz
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Kyle Flattery
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Jessica Capri
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Katie Yao
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Siqi Wu
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | | | | | | | - Wallace B Thoreson
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, NE, USA
| | | | - Neena B Haider
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA.
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de Carvalho ER, Robson AG, Arno G, Boon CJF, Webster AA, Michaelides M. Enhanced S-Cone Syndrome: Spectrum of Clinical, Imaging, Electrophysiologic, and Genetic Findings in a Retrospective Case Series of 56 Patients. Ophthalmol Retina 2021; 5:195-214. [PMID: 32679203 PMCID: PMC7861019 DOI: 10.1016/j.oret.2020.07.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 11/19/2022]
Abstract
PURPOSE To describe the detailed phenotype, long-term clinical course, clinical variability, and genotype of patients with enhanced S-cone syndrome (ESCS). DESIGN Retrospective case series. PARTICIPANTS Fifty-six patients with ESCS. METHODS Clinical history, examination, imaging, and electrophysiologic findings of 56 patients (age range, 1-75 years) diagnosed with ESCS were reviewed. Diagnosis was established by molecular confirmation of disease-causing variants in the NR2E3 gene (n = 38) or by diagnostic full-field electroretinography findings (n = 18). MAIN OUTCOME MEASURES Age at onset of visual symptoms, best-corrected visual acuity (BCVA), quantitative age-related electrophysiologic decline, and imaging findings. RESULTS Mean age at onset of visual symptoms was 4.0 years, and median age at presentation was 20.5 years, with mean follow-up interval being 6.1 years. Six patients were assessed once. Disease-causing variants in NR2E3 were identified in 38 patients. Mean BCVA of the better-seeing eye was 0.32 logarithm of the minimum angle of resolution (logMAR) at baseline and 0.39 logMAR at follow-up. In most eyes (76% [76/100]), BCVA remained stable, with a mean BCVA change of 0.07 logMAR during follow-up. Nyctalopia was the most common initial symptom, reported in 92.9% of patients (52/56). Clinical findings were highly variable and included foveomacular schisis (41.1% [26/56]), yellow-white dots (57.1% [32/56]), nummular pigmentation (85.7% [48/56]), torpedo-like lesions (10.7% [6/56]), and circumferential subretinal fibrosis (7.1% [4/56]). Macular and peripheral patterns of autofluorescence were classified as (1) minimal change, (2) hypoautofluorescent (mild diffuse, moderate speckled, moderate diffuse, or advanced), or (3) hyperautofluorescent flecks. One patient showed undetectable electroretinography findings; quantification of main electroretinography components in all other patients revealed amplitude and peak time variability but with pathognomonic electroretinography features. The main electroretinography components showed evidence of age-related worsening over 6.7 decades, at a rate indistinguishable from that seen in unaffected control participants. Eighteen sequence variants in NR2E3 were identified, including 4 novel missense changes. CONCLUSIONS Enhanced S-cone syndrome has a highly variable phenotype with relative clinical and imaging stability over time. Most electroretinography findings have pathognomonic features, but quantitative assessment reveals variability and a normal mean rate of age-related decline, consistent with largely nonprogressive peripheral retinal dysfunction.
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Affiliation(s)
- Emanuel R de Carvalho
- Moorfields Eye Hospital, London, United Kingdom; Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Anthony G Robson
- Moorfields Eye Hospital, London, United Kingdom; Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Gavin Arno
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Camiel J F Boon
- Department of Ophthalmology, Amsterdam University Medical Centers, Amsterdam, The Netherlands; Department of Ophthalmology, Leiden University Medical Center, Leiden, The Netherlands
| | - Andrew A Webster
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Michel Michaelides
- Moorfields Eye Hospital, London, United Kingdom; UCL Institute of Ophthalmology, University College London, London, United Kingdom.
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Iannaccone A, Brabbit E, Lopez-Miro C, Love Z, Griffiths V, Kedrov M, Haider NB. Interspecies Correlations between Human and Mouse NR2E3-Associated Recessive Disease. J Clin Med 2021; 10:jcm10030475. [PMID: 33513943 PMCID: PMC7865474 DOI: 10.3390/jcm10030475] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 11/16/2022] Open
Abstract
NR2E3-associated recessive disease in humans is historically defined by congenital night blinding retinopathy, characterized by an initial increase in short-wavelength (S)-cone sensitivity and progressive loss of rod and cone function. The retinal degeneration 7 (rd7) murine model, harboring a recessive mutation in the mouse ortholog of NR2E3, has been a well-studied disease model and recently evaluated as a therapeutic model for NR2E3-associated retinal degenerations. This study aims to draw parallels between human and mouse NR2E3-related disease through examination of spectral domain optical coherence tomography (SD-OCT) imaging between different stage of human disease and its murine counterpart. We propose that SD-OCT is a useful non-invasive diagnostic tool to compare human clinical dystrophy presentation with that of the rd7 mouse and make inference that may be of therapeutically relevance. Additionally, a longitudinal assessment of rd7 disease progression, utilizing available clinical data from our patients as well as extensive retrospective analysis of visual acuity data from published cases of human NR2E3-related disease, was curated to identify further valuable correlates between human and mouse Nr2e3 disease. Results of this study validate the slow progression of NR2E3-associated disease in humans and the rd7 mice and identify SD-OCT characteristics in patients at or near the vascular arcades that correlate well with the whorls and rosettes that are seen also in the rd7 mouse and point to imaging features that appear to be associated with better preserved S-cone mediated retinal function. The correlation of histological findings between rd7 mice and human imaging provides a solid foundation for diagnostic use of pathophysiological and prognostic information to further define characteristics and a relevant timeline for therapeutic intervention in the field of NR2E3-associated retinopathies.
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Affiliation(s)
- Alessandro Iannaccone
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
- Correspondence: (A.I.); (N.B.H.)
| | - Emily Brabbit
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA; (E.B.); (Z.L.)
| | - Christiaan Lopez-Miro
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
| | - Zoe Love
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA; (E.B.); (Z.L.)
| | - Victoria Griffiths
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
| | - Marina Kedrov
- Center for Retinal Degenerations and Ophthalmic Genetic Diseases, Department of Ophthalmology, Duke Eye Center, Duke University School of Medicine, Durham, NC 27710, USA; (C.L.-M.); (V.G.); (M.K.)
| | - Neena B. Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA; (E.B.); (Z.L.)
- Correspondence: (A.I.); (N.B.H.)
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Nr2e3 functional domain ablation by CRISPR-Cas9D10A identifies a new isoform and generates retinitis pigmentosa and enhanced S-cone syndrome models. Neurobiol Dis 2020; 146:105122. [PMID: 33007388 DOI: 10.1016/j.nbd.2020.105122] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/23/2020] [Accepted: 09/25/2020] [Indexed: 12/18/2022] Open
Abstract
Mutations in NR2E3 cause retinitis pigmentosa (RP) and enhanced S-cone syndrome (ESCS) in humans. This gene produces a large isoform encoded in 8 exons and a previously unreported shorter isoform of 7 exons, whose function is unknown. We generated two mouse models by targeting exon 8 of Nr2e3 using CRISPR/Cas9-D10A nickase. Allele Δ27 is an in-frame deletion of 27 bp that ablates the dimerization domain H10, whereas allele ΔE8 (full deletion of exon 8) produces only the short isoform, which lacks the C-terminal part of the ligand binding domain (LBD) that encodes both H10 and the AF2 domain involved in the Nr2e3 repressor activity. The Δ27 mutant shows developmental alterations and a non-progressive electrophysiological dysfunction that resembles the ESCS phenotype. The ΔE8 mutant exhibits progressive retinal degeneration, as occurs in human RP patients. Our mutants suggest a role for Nr2e3 as a cone-patterning regulator and provide valuable models for studying mechanisms of NR2E3-associated retinal dystrophies and evaluating potential therapies.
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15
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Core-clock genes Period 1 and 2 regulate visual cascade and cell cycle components during mouse eye development. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194623. [PMID: 32795630 DOI: 10.1016/j.bbagrm.2020.194623] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 08/07/2020] [Accepted: 08/07/2020] [Indexed: 12/16/2022]
Abstract
The retinas from Period 1 (Per1) and Period 2 (Per2) double-mutant mice (Per1-/-Per2Brdm1) display abnormal blue-cone distribution associated with a reduction in cone opsin mRNA and protein levels, up to 1 year of age. To reveal the molecular mechanisms by which Per1 and Per2 control retina development, we analyzed genome-wide gene expression differences between wild-type (WT) and Per1-/-Per2Brdm1 mice across ocular developmental stages (E15, E18 and P3). All clock genes displayed changes in transcript levels along with normal eye development. RNA-Seq data show major gene expression changes between WT and mutant eyes, with the number of differentially expressed genes (DEG) increasing with developmental age. Functional annotation of the genes showed that the most significant changes in expression levels in mutant mice involve molecular pathways relating to circadian rhythm signaling at E15 and E18. At P3, the visual cascade and the cell cycle were respectively higher and lower expressed compared to WT eyes. Overall, our study provides new insights into signaling pathways -phototransduction and cell cycle- controlled by the circadian clock in the eye during development.
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16
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Di Scipio M, Tavares E, Deshmukh S, Audo I, Green-Sanderson K, Zubak Y, Zine-Eddine F, Pearson A, Vig A, Tang CY, Mollica A, Karas J, Tumber A, Yu CW, Billingsley G, Wilson MD, Zeitz C, Héon E, Vincent A. Phenotype Driven Analysis of Whole Genome Sequencing Identifies Deep Intronic Variants that Cause Retinal Dystrophies by Aberrant Exonization. Invest Ophthalmol Vis Sci 2020; 61:36. [PMID: 32881472 PMCID: PMC7443117 DOI: 10.1167/iovs.61.10.36] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/16/2020] [Indexed: 02/07/2023] Open
Abstract
Purpose To demonstrate the effectiveness of combining retinal phenotyping and focused variant filtering from genome sequencing (GS) in identifying deep intronic disease causing variants in inherited retinal dystrophies. Methods Affected members from three pedigrees with classical enhanced S-cone syndrome (ESCS; Pedigree 1), congenital stationary night blindness (CSNB; Pedigree 2), and achromatopsia (ACHM; Pedigree 3), respectively, underwent detailed ophthalmologic evaluation, optical coherence tomography, and electroretinography. The probands underwent panel-based genetic testing followed by GS analysis. Minigene constructs (NR2E3, GPR179 and CNGB3) and patient-derived cDNA experiments (NR2E3 and GPR179) were performed to assess the functional effect of the deep intronic variants. Results The electrophysiological findings confirmed the clinical diagnosis of ESCS, CSNB, and ACHM in the respective pedigrees. Panel-based testing revealed heterozygous pathogenic variants in NR2E3 (NM_014249.3; c.119-2A>C; Pedigree 1) and CNGB3 (NM_019098.4; c.1148delC/p.Thr383Ilefs*13; Pedigree 3). The GS revealed heterozygous deep intronic variants in Pedigrees 1 (NR2E3; c.1100+1124G>A) and 3 (CNGB3; c.852+4751A>T), and a homozygous GPR179 variant in Pedigree 2 (NM_001004334.3; c.903+343G>A). The identified variants segregated with the phenotype in all pedigrees. All deep intronic variants were predicted to generate a splice acceptor gain causing aberrant exonization in NR2E3 [89 base pairs (bp)], GPR179 (197 bp), and CNGB3 (73 bp); splicing defects were validated through patient-derived cDNA experiments and/or minigene constructs and rescued by antisense oligonucleotide treatment. Conclusions Deep intronic mutations contribute to missing heritability in retinal dystrophies. Combining results from phenotype-directed gene panel testing, GS, and in silico splice prediction tools can help identify these difficult-to-detect pathogenic deep intronic variants.
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Affiliation(s)
- Matteo Di Scipio
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Erika Tavares
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Shriya Deshmukh
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- CHNO des Quinze-Vingts, INSERM-DGOS CIC1423, Paris, France
- University College London Institute of Ophthalmology, London, United Kingdom
| | - Kit Green-Sanderson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Yuliya Zubak
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Fayçal Zine-Eddine
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Alexander Pearson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Anjali Vig
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Chen Yu Tang
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Antonio Mollica
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Jonathan Karas
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Anupreet Tumber
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
| | - Caberry W. Yu
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Gail Billingsley
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
| | - Michael D. Wilson
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Elise Héon
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
| | - Ajoy Vincent
- Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, Canada
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada
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Targeting of the NRL Pathway as a Therapeutic Strategy to Treat Retinitis Pigmentosa. J Clin Med 2020; 9:jcm9072224. [PMID: 32668775 PMCID: PMC7408925 DOI: 10.3390/jcm9072224] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 06/28/2020] [Accepted: 07/07/2020] [Indexed: 12/26/2022] Open
Abstract
Retinitis pigmentosa (RP) is an inherited retinal dystrophy (IRD) with a prevalence of 1:4000, characterized by initial rod photoreceptor loss and subsequent cone photoreceptor loss with accompanying nyctalopia, visual field deficits, and visual acuity loss. A diversity of causative mutations have been described with autosomal dominant, autosomal recessive, and X-linked inheritance and sporadic mutations. The diversity of mutations makes gene therapy challenging, highlighting the need for mutation-agnostic treatments. Neural leucine zipper (NRL) and NR2E3 are factors important for rod photoreceptor cell differentiation and homeostasis. Germline mutations in NRL or NR2E3 leads to a loss of rods and an increased number of cones with short wavelength opsin in both rodents and humans. Multiple groups have demonstrated that inhibition of NRL or NR2E3 activity in the mature retina could endow rods with certain properties of cones, which prevents cell death in multiple rodent RP models with diverse mutations. In this review, we summarize the literature on NRL and NR2E3, therapeutic strategies of NRL/NR2E3 modulation in preclinical RP models, as well as future directions of research. In summary, inhibition of the NRL/NR2E3 pathway represents an intriguing mutation agnostic and disease-modifying target for the treatment of RP.
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18
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Induction of Rod and Cone Photoreceptor-Specific Progenitors from Stem Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019. [PMID: 31884669 DOI: 10.1007/978-3-030-27378-1_90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register]
Abstract
Retinal degeneration includes a variety of diseases for which there is no regenerative therapy. Cellular transplantation is one potential approach for future therapy for retinal degeneration, and stem cells have emerged as a promising source for future cell therapeutics. One major barrier to therapy is the ability to specify individual photoreceptor lineages from a variety of stem cell sources. In this review, we focus on photoreceptor genesis from progenitor populations in the developing embryo and how this understanding has given us the tools to manipulate cultures to specific unique rod and cone lineages from adult stem cell populations. We discuss experiments and evidence uncovering the lineage mechanisms at play in the establishment of fate-specific rod and cone photoreceptor progenitors. This may lead to an improved understanding of retinal development in vivo, as well as new cell sources for transplantation.
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19
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Correction of NR2E3 Associated Enhanced S-cone Syndrome Patient-specific iPSCs using CRISPR-Cas9. Genes (Basel) 2019; 10:genes10040278. [PMID: 30959774 PMCID: PMC6523438 DOI: 10.3390/genes10040278] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 12/24/2022] Open
Abstract
Enhanced S-cone syndrome (ESCS) is caused by recessive mutations in the photoreceptor cell transcription factor NR2E3. Loss of NR2E3 is characterized by repression of rod photoreceptor cell gene expression, over-expansion of the S-cone photoreceptor cell population, and varying degrees of M- and L-cone photoreceptor cell development. In this study, we developed a CRISPR-based homology-directed repair strategy and corrected two different disease-causing NR2E3 mutations in patient-derived induced pluripotent stem cells (iPSCs) generated from two affected individuals. In addition, one patient’s iPSCs were differentiated into retinal cells and NR2E3 transcription was evaluated in CRISPR corrected and uncorrected clones. The patient’s c.119-2A>C mutation caused the inclusion of a portion of intron 1, the creation of a frame shift, and generation of a premature stop codon. In summary, we used a single set of CRISPR reagents to correct different mutations in iPSCs generated from two individuals with ESCS. In doing so we demonstrate the advantage of using retinal cells derived from affected patients over artificial in vitro model systems when attempting to demonstrate pathophysiologic mechanisms of specific mutations.
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20
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Kong Y, Zhao L, Charette JR, Hicks WL, Stone L, Nishina PM, Naggert JK. An FRMD4B variant suppresses dysplastic photoreceptor lesions in models of enhanced S-cone syndrome and of Nrl deficiency. Hum Mol Genet 2019; 27:3340-3352. [PMID: 29947801 DOI: 10.1093/hmg/ddy238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 06/04/2018] [Indexed: 12/16/2022] Open
Abstract
Photoreceptor dysplasia, characterized by formation of folds and (pseudo-)rosettes in the outer retina, is associated with loss of functional nuclear receptor subfamily 2 group E member 3 (NR2E3) and neural retina leucine-zipper (NRL) in both humans and mice. A sensitized chemical mutagenesis study to identify genetic modifiers that suppress photoreceptor dysplasia in Nr2e3rd7mutant mice identified line Tvrm222, which exhibits a normal fundus appearance in the presence of the rd7 mutation. The Tvrm222 modifier of Nr2e3rd7/rd7 was localized to Chromosome 6 and identified as a missense mutation in the FERM domain containing 4B (Frmd4b) gene. The variant is predicted to cause the substitution of a serine residue 938 with proline (S938P). The Frmd4bTvrm222 allele was also found to suppress outer nuclear layer (ONL) rosettes in Nrl-/- mice. Fragmentation of the external limiting membrane (ELM), normally observed in rd7 and Nrl-/-mouse retinas, was absent in the presence of the Frmd4bTvrm222 allele. FRMD4B, a binding partner of cytohesin 3, is proposed to participate in cell junction remodeling. Its biological function in photoreceptor dysplasia has not been previously examined. In vitro experiments showed that the FRMD4B938P variant fails to be efficiently recruited to the cell surface upon insulin stimulation. In addition, we found a reduction in protein kinase B phosphorylation and increased levels of cell junction proteins, Catenin beta 1 and tight junction protein 1, associated with the cell membrane in Tvrm222 retinas. Taken together, this study reveals a critical role of FRMD4B in maintaining ELM integrity and in rescuing morphological abnormalities of the ONL in photoreceptor dysplasia.
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Affiliation(s)
- Yang Kong
- Jackson Laboratory, Bar Harbor, ME, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME, USA
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21
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Garafalo AV, Calzetti G, Cideciyan AV, Roman AJ, Saxena S, Sumaroka A, Choi W, Wright AF, Jacobson SG. Cone Vision Changes in the Enhanced S-Cone Syndrome Caused by NR2E3 Gene Mutations. Invest Ophthalmol Vis Sci 2019; 59:3209-3219. [PMID: 29971438 DOI: 10.1167/iovs.18-24518] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To determine the progression of cone vision loss in patients with recessive disease from NR2E3 gene mutations. Methods Patients with NR2E3 mutations (n = 37) were studied as a retrospective observational case series clinically and with chromatic static perimetry. Patients were investigated cross-sectionally, and a subset was followed longitudinally. Results Patients showed a range of visual acuities; there was no clear relationship to age. With kinetic perimetry (V4e target), a full field could be retained over many years. Other patients showed progression from a full field, with or without pericentral scotomas, to a small central island. Three patterns of S-cone function were defined, based on percentage of hypersensitive S-cone loci in the field. From occupying most of the visual field, hyperfunctioning S-cone loci could diminish in percent, remaining largely in the periphery. Normal S-cone functioning then dominates, followed by the appearance of an annular region of abnormal S-cone loci approximately 10° to 40° from the fovea. Overall, S-cone sensitivity declined 2.6 times faster than L/M-cone sensitivity. Conclusions Murine proof-of-concept studies suggest that clinical trials of patients with NR2E3 mutations may be forthcoming. Patterns of S-cone hyperfunction across the field would serve as a means to categorize patients as entry criteria or cohort selection in clinical trials. S-cone perimetry can be measured in the clinic and would be the logical efficacy monitor for therapeutic strategies. Given further understanding of the natural history of the disease, targeting the annular region of S-cone dysfunction for a focal therapy or for monitoring in a retina-wide intervention warrants consideration.
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Affiliation(s)
- Alexandra V Garafalo
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Giacomo Calzetti
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Artur V Cideciyan
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alejandro J Roman
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Supna Saxena
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alexander Sumaroka
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Windy Choi
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alan F Wright
- Medical Research Council Human Genetics Unit, Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Samuel G Jacobson
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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22
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Xie S, Han S, Qu Z, Liu F, Li J, Yu S, Reilly J, Tu J, Liu X, Lu Z, Hu X, Yimer TA, Qin Y, Huang Y, Lv Y, Jiang T, Shu X, Tang Z, Jia H, Wong F, Liu M. Knockout of Nr2e3 prevents rod photoreceptor differentiation and leads to selective L-/M-cone photoreceptor degeneration in zebrafish. Biochim Biophys Acta Mol Basis Dis 2019; 1865:1273-1283. [PMID: 30684641 DOI: 10.1016/j.bbadis.2019.01.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 01/20/2019] [Accepted: 01/21/2019] [Indexed: 01/28/2023]
Abstract
Mutations in the photoreceptor cell-specific nuclear receptor gene Nr2e3 increased the number of S-cone photoreceptors in human and murine retinas and led to retinal degeneration that involved photoreceptor and non-photoreceptor cells. The mechanisms underlying these complex phenotypes remain unclear. In the hope of understanding the precise role of Nr2e3 in photoreceptor cell fate determination and differentiation, we generated a line of Nr2e3 knockout zebrafish using CRISPR technology. In these Nr2e3-null animals, rod precursors undergo terminal mitoses but fail to differentiate as rods. Rod-specific genes are not expressed and the outer segment (OS) fails to form. Formation and differentiation of cone photoreceptors is normal. Specifically, there is no increase in the number of UV-cone or S-cone photoreceptors. Laminated retinal structure is maintained. After normal development, L-/M-cones selectively degenerate, with progressive shortening of OS that starts at age 1 month. The amount of cone phototransduction proteins is concomitantly reduced, whereas UV- and S-cones have normal OS lengths even at age 10 months. In vitro studies show Nr2e3 synergizes with Crx and Nrl to enhance rhodopsin gene expression. Nr2e3 does not affect cone opsin expression. Our results extend the knowledge of Nr2e3's roles and have specific implications for the interpretation of the phenotypes observed in human and murine retinas. Furthermore, our model may offer new opportunities in finding treatments for enhanced S-cone syndrome (ESCS) and other retinal degenerative diseases.
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Affiliation(s)
- Shanglun Xie
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Shanshan Han
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Zhen Qu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Fei Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Jingzhen Li
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Shanshan Yu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - James Reilly
- Department of Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, Scotland, United Kingdom of Great Britain and Northern Ireland
| | - Jiayi Tu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Xiliang Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Zhaojing Lu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Xuebin Hu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Tinsae Assefa Yimer
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Yayun Qin
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Yuwen Huang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Yuexia Lv
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Tao Jiang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Xinhua Shu
- Department of Life Sciences, Glasgow Caledonian University, Glasgow G4 0BA, Scotland, United Kingdom of Great Britain and Northern Ireland
| | - Zhaohui Tang
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China
| | - Haibo Jia
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
| | - Fulton Wong
- Department of Ophthalmology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Mugen Liu
- Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
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Ueda K, Onishi A, Ito SI, Nakamura M, Takahashi M. Generation of three-dimensional retinal organoids expressing rhodopsin and S- and M-cone opsins from mouse stem cells. Biochem Biophys Res Commun 2018; 495:2595-2601. [DOI: 10.1016/j.bbrc.2017.12.092] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 12/17/2017] [Indexed: 12/13/2022]
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Meyer KJ, Anderson MG. Genetic modifiers as relevant biological variables of eye disorders. Hum Mol Genet 2017; 26:R58-R67. [PMID: 28482014 DOI: 10.1093/hmg/ddx180] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 05/05/2017] [Indexed: 12/19/2022] Open
Abstract
From early in the study of mammalian genetics, it was clear that modifiers can have a striking influence on phenotypes. Today, several modifiers have now been studied in enough detail to allow a glimpse of how they function and influence our perspective of disease. With respect to diseases of the eye, some modifiers are an important source of phenotypic variation that can elucidate how genes function in networks to collectively shape ocular anatomy and physiology, thus influencing our understanding of basic biology. Other modifiers represent an opportunity for new therapeutic targets, whose manipulation could be used to mitigate ophthalmic disease. Here, we review progress in the study of genetic modifiers of eye disorders, with examples from mice and humans that together illustrate the ubiquitous nature of genetic modifiers and why they are relevant biological variables in experimental design. Special emphasis is given to ophthalmic modifiers in mice, especially those relevant to selection of genetic background and those that might inadvertently be a source of experimental variability. These modifiers are capable of influencing interpretations of many experiments using targeted genome manipulations such as knockouts or transgenics. Whereas there are fewer examples of modifiers of eye disorders in humans with a molecular identification, there is ample evidence that they exist and should be considered as a relevant biological variable in human genetic studies as well.
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Affiliation(s)
- Kacie J Meyer
- Department of Molecular Physiology and Biophysics.,Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA
| | - Michael G Anderson
- Department of Molecular Physiology and Biophysics.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA.,Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, IA 52242, USA.,Center for Prevention and Treatment of Visual Loss, Iowa City Veterans Administration Medical Center, Iowa City, IA 52242, USA
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25
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Mechanisms of Photoreceptor Patterning in Vertebrates and Invertebrates. Trends Genet 2017; 32:638-659. [PMID: 27615122 DOI: 10.1016/j.tig.2016.07.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 07/25/2016] [Accepted: 07/28/2016] [Indexed: 11/22/2022]
Abstract
Across the animal kingdom, visual systems have evolved to be uniquely suited to the environments and behavioral patterns of different species. Visual acuity and color perception depend on the distribution of photoreceptor (PR) subtypes within the retina. Retinal mosaics can be organized into three broad categories: stochastic/regionalized, regionalized, and ordered. We describe here the retinal mosaics of flies, zebrafish, chickens, mice, and humans, and the gene regulatory networks controlling proper PR specification in each. By drawing parallels in eye development between these divergent species, we identify a set of conserved organizing principles and transcriptional networks that govern PR subtype differentiation.
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Nakamura PA, Shimchuk AA, Tang S, Wang Z, DeGolier K, Ding S, Reh TA. Small molecule Photoregulin3 prevents retinal degeneration in the RhoP23H mouse model of retinitis pigmentosa. eLife 2017; 6. [PMID: 29148976 PMCID: PMC5693111 DOI: 10.7554/elife.30577] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 10/24/2017] [Indexed: 12/25/2022] Open
Abstract
Regulation of rod gene expression has emerged as a potential therapeutic strategy to treat retinal degenerative diseases like retinitis pigmentosa (RP). We previously reported on a small molecule modulator of the rod transcription factor Nr2e3, Photoregulin1 (PR1), that regulates the expression of photoreceptor-specific genes. Although PR1 slows the progression of retinal degeneration in models of RP in vitro, in vivo analyses were not possible with PR1. We now report a structurally unrelated compound, Photoregulin3 (PR3) that also inhibits rod photoreceptor gene expression, potentially though Nr2e3 modulation. To determine the effectiveness of PR3 as a potential therapy for RP, we treated RhoP23H mice with PR3 and assessed retinal structure and function. PR3-treated RhoP23H mice showed significant structural and functional photoreceptor rescue compared with vehicle-treated littermate control mice. These results provide further support that pharmacological modulation of rod gene expression provides a potential strategy for the treatment of RP. There are several diseases that cause people to lose their eyesight and become blind. One of these diseases, called retinitis pigmentosa, kills cells at the back of the eye known as rod cells. At first, it affects vision in low light and peripheral vision, but later it affects vision during the daytime as well. There are no effective treatments for patients with retinitis pigmentosa. Yet previous genetic studies have shown that disrupting the activity of genes in rod cells can slow the progression of the disease and preserve vision in mice. As for all genes, proteins called transcription factors regulate the activity of rod cell genes. Nakamura et al. now report the discovery of a small drug-like molecule, that they name Photoregulin3, which alters the activity of a transcription factor that regulates rod genes. In follow-up experiments, mice with a mutation that replicates many of the features of retinitis pigmentosa were given Photoregulin3 to see if it could slow the progression of the disease. Indeed, Photoregulin3 could stop many of the rod cells from degenerating in the treated mice. At the end of the experiment, the mice treated with this small molecule had about twice as many rods as the control mice. The treated mice also responded better to flashes of light. Nakamura et al. hope that the findings will one day benefit patients with retinitis pigmentosa. But first more research needs to be done before testing Photoregulin3 in humans. For example, the drug-like molecule needs to be made more potent, and if possible adapted to work when given orally, meaning patients could take it as a pill.
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Affiliation(s)
- Paul A Nakamura
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, United States
| | - Andy A Shimchuk
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, United States
| | - Shibing Tang
- Department of Pharmaceutical Chemistry, UCSF School of Pharmacy, University of California, San Francisco, San Francisco, United States
| | - Zhizhi Wang
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, United States
| | - Kole DeGolier
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, United States
| | - Sheng Ding
- Department of Pharmaceutical Chemistry, UCSF School of Pharmacy, University of California, San Francisco, San Francisco, United States
| | - Thomas A Reh
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, United States
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27
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Loss of NR2E3 represses AHR by LSD1 reprogramming, is associated with poor prognosis in liver cancer. Sci Rep 2017; 7:10662. [PMID: 28878246 PMCID: PMC5587550 DOI: 10.1038/s41598-017-11106-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 08/18/2017] [Indexed: 11/15/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR) plays crucial roles in inflammation, metabolic disorder, and cancer. However, the molecular mechanisms regulating AHR expression remain unknown. Here, we found that an orphan nuclear NR2E3 maintains AHR expression, and forms an active transcriptional complex with transcription factor Sp1 and coactivator GRIP1 in MCF-7 human breast and HepG2 liver cancer cell lines. NR2E3 loss promotes the recruitment of LSD1, a histone demethylase of histone 3 lysine 4 di-methylation (H3K4me2), to the AHR gene promoter region, resulting in repression of AHR expression. AHR expression and responsiveness along with H3K4me2 were significantly reduced in the livers of Nr2e3rd7 (Rd7) mice that express low NR2E3 relative to the livers of wild-type mice. SP2509, an LSD1 inhibitor, fully restored AHR expression and H3K4me2 levels in Rd7 mice. Lastly, we demonstrated that both AHR and NR2E3 are significantly associated with good clinical outcomes in liver cancer. Together, our results reveal a novel link between NR2E3, AHR, and liver cancer via LSD1-mediated H3K4me2 histone modification in liver cancer development.
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28
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Nakamura PA, Tang S, Shimchuk AA, Ding S, Reh TA. Potential of Small Molecule-Mediated Reprogramming of Rod Photoreceptors to Treat Retinitis Pigmentosa. Invest Ophthalmol Vis Sci 2017; 57:6407-6415. [PMID: 27893103 PMCID: PMC5134355 DOI: 10.1167/iovs.16-20177] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Mutations in rod photoreceptor genes can cause retinitis pigmentosa (RP). Rod gene expression is regulated by the nuclear hormone receptor, Nr2e3. Genetic deletion of Nr2e3 reprograms rods into cells that resemble cone photoreceptors, and might therefore prevent their death from some forms of RP. There are no identified ligands for Nr2e3; however, reverse agonists might mimic the genetic rescue effect and may be therapeutically useful for the treatment of RP. Methods We screened for small molecule modulators of Nr2e3 using primary retinal cell cultures and characterized the most potent, which we have named photoregulin1 (PR1), in vitro and in vivo. We also tested the ability of PR1 to slow the progression of photoreceptor degeneration in two common mouse models of autosomal dominant RP, the RhoP23H and the Pde6brd1 mutations. Results In developing retina, PR1 causes a decrease in rod gene expression and an increase in S opsin+ cones. Photoregulin1 continues to inhibit rod gene expression in adult mice. When applied to two mouse models of RP, PR1 slows the degeneration of photoreceptors. Conclusions Chemical compounds identified as modulators of Nr2e3 activity may be useful for the treatment of RP through their effects on expression of disease-causing mutant genes.
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Affiliation(s)
- Paul A Nakamura
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, Washington, United States
| | - Shibing Tang
- University of California-San Francisco, UCSF School of Pharmacy, Department of Pharmaceutical Chemistry, San Francisco California, United States
| | - Andy A Shimchuk
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, Washington, United States
| | - Sheng Ding
- University of California-San Francisco, UCSF School of Pharmacy, Department of Pharmaceutical Chemistry, San Francisco California, United States
| | - Thomas A Reh
- Department of Biological Structure, University of Washington, School of Medicine, Seattle, Washington, United States
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29
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Olivares AM, Jelcick AS, Reinecke J, Leehy B, Haider A, Morrison MA, Cheng L, Chen DF, DeAngelis MM, Haider NB. Multimodal Regulation Orchestrates Normal and Complex Disease States in the Retina. Sci Rep 2017; 7:690. [PMID: 28386079 PMCID: PMC5429617 DOI: 10.1038/s41598-017-00788-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 03/13/2017] [Indexed: 12/20/2022] Open
Abstract
Regulation of biological processes occurs through complex, synergistic mechanisms. In this study, we discovered the synergistic orchestration of multiple mechanisms regulating the normal and diseased state (age related macular degeneration, AMD) in the retina. We uncovered gene networks with overlapping feedback loops that are modulated by nuclear hormone receptors (NHR), miRNAs, and epigenetic factors. We utilized a comprehensive filtering and pathway analysis strategy comparing miRNA and microarray data between three mouse models and human donor eyes (normal and AMD). The mouse models lack key NHRS (Nr2e3, RORA) or epigenetic (Ezh2) factors. Fifty-four total miRNAs were differentially expressed, potentially targeting over 150 genes in 18 major representative networks including angiogenesis, metabolism, and immunity. We identified sixty-eight genes and 5 miRNAS directly regulated by NR2E3 and/or RORA. After a comprehensive analysis, we discovered multimodal regulation by miRNA, NHRs, and epigenetic factors of three miRNAs (miR-466, miR1187, and miR-710) and two genes (Ell2 and Entpd1) that are also associated with AMD. These studies provide insight into the complex, dynamic modulation of gene networks as well as their impact on human disease, and provide novel data for the development of innovative and more effective therapeutics.
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Affiliation(s)
- A M Olivares
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - A S Jelcick
- Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - J Reinecke
- Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - B Leehy
- Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - A Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - M A Morrison
- Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - L Cheng
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - D F Chen
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - M M DeAngelis
- Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - N B Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America.
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30
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Broadgate S, Yu J, Downes SM, Halford S. Unravelling the genetics of inherited retinal dystrophies: Past, present and future. Prog Retin Eye Res 2017; 59:53-96. [PMID: 28363849 DOI: 10.1016/j.preteyeres.2017.03.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 03/21/2017] [Accepted: 03/23/2017] [Indexed: 02/07/2023]
Abstract
The identification of the genes underlying monogenic diseases has been of interest to clinicians and scientists for many years. Using inherited retinal dystrophies as an example of monogenic disease we describe the history of molecular genetic techniques that have been pivotal in the discovery of disease causing genes. The methods that were developed in the 1970's and 80's are still in use today but have been refined and improved. These techniques enabled the concept of the Human Genome Project to be envisaged and ultimately realised. When the successful conclusion of the project was announced in 2003 many new tools and, as importantly, many collaborations had been developed that facilitated a rapid identification of disease genes. In the post-human genome project era advances in computing power and the clever use of the properties of DNA replication has allowed the development of next-generation sequencing technologies. These methods have revolutionised the identification of disease genes because for the first time there is no need to define the position of the gene in the genome. The use of next generation sequencing in a diagnostic setting has allowed many more patients with an inherited retinal dystrophy to obtain a molecular diagnosis for their disease. The identification of novel genes that have a role in the development or maintenance of retinal function is opening up avenues of research which will lead to the development of new pharmacological and gene therapy approaches. Neither of which can be used unless the defective gene and protein is known. The continued development of sequencing technologies also holds great promise for the advent of truly personalised medicine.
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Affiliation(s)
- Suzanne Broadgate
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Levels 5 and 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK
| | - Jing Yu
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Levels 5 and 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK
| | - Susan M Downes
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, Oxford, OX3 9DU, UK
| | - Stephanie Halford
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Levels 5 and 6 West Wing, John Radcliffe Hospital, Headley Way, Oxford, OX3 9DU, UK.
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31
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Choudhary M, Malek G. Rethinking Nuclear Receptors as Potential Therapeutic Targets for Retinal Diseases. ACTA ACUST UNITED AC 2016; 21:1007-1018. [PMID: 27455994 DOI: 10.1177/1087057116659856] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Collectively, retinal diseases, including age-related macular degeneration, retinitis pigmentosa, and diabetic retinopathy, result in severe vision impairment worldwide. The absence and/or limited availability of successful drug therapies for these blinding disorders necessitates further understanding their pathobiology and identifying new targetable signaling pathways. Nuclear receptors are transcription regulators of many key aspects of human physiology, as well as pathophysiology, with reported roles in development, aging, and disease. Some of the pathways regulated by nuclear receptors include, but are not limited to, angiogenesis, inflammation, and lipid metabolic dysregulation, mechanisms also important in the initiation and development of several retinal diseases. Herein, we present an overview of the biology of three diseases affecting the posterior eye, summarize a growing body of evidence that suggests direct or indirect involvement of nuclear receptors in disease progression, and discuss the therapeutic potential of targeting nuclear receptors for treatment.
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Affiliation(s)
- Mayur Choudhary
- 1 Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA
| | - Goldis Malek
- 1 Department of Ophthalmology, Duke University School of Medicine, Durham, NC, USA.,2 Department of Pathology, Duke University School of Medicine, Durham, NC, USA
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32
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Boulling A, Escher P. Coupling ex vivo electroporation of mouse retinas and luciferase reporter assays to assess rod-specific promoter activity. Exp Eye Res 2016; 148:79-82. [PMID: 27268947 DOI: 10.1016/j.exer.2016.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 05/30/2016] [Accepted: 06/01/2016] [Indexed: 11/26/2022]
Abstract
Ex vivo electroporation of mouse retinas is an established tool to modulate gene expression and to study cell type-specific gene expression. Here we coupled ex vivo electroporation to luciferase reporter assays to facilitate the study of rod-photoreceptor-specific gene promoters. The activity of the rod-specific proximal bovine rhodopsin promoter was significantly increased in C57BL/6J wild-type retinas at postnatal days 1 and 7 by 3.4-fold and 8.7-fold respectively. In C57BL/6J Nr2e3(rd7/rd7) retinas, where the rod photoreceptor-specific nuclear receptor Nr2e3 is not expressed, a significant increase by 2.5-fold was only observed at postnatal day 7. Cone-specific S-opsin promoter activity was not modulated in C57BL/6J wild-type and Nr2e3(rd7/rd7) retinas. Taken together, we describe an easily implementable protocol to assess rod-specific promoter activity in a physiological context resembling that of the developing postnatal mouse retina.
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Affiliation(s)
- Arnaud Boulling
- Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, 1004 Lausanne, Switzerland; Institute for Research in Ophthalmology, 1950 Sion, Switzerland
| | - Pascal Escher
- Department of Ophthalmology, University of Lausanne, Jules-Gonin Eye Hospital, 1004 Lausanne, Switzerland.
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33
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Olivares AM, Moreno-Ramos OA, Haider NB. Role of Nuclear Receptors in Central Nervous System Development and Associated Diseases. J Exp Neurosci 2016; 9:93-121. [PMID: 27168725 PMCID: PMC4859451 DOI: 10.4137/jen.s25480] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 01/06/2016] [Accepted: 01/07/2016] [Indexed: 11/13/2022] Open
Abstract
The nuclear hormone receptor (NHR) superfamily is composed of a wide range of receptors involved in a myriad of important biological processes, including development, growth, metabolism, and maintenance. Regulation of such wide variety of functions requires a complex system of gene regulation that includes interaction with transcription factors, chromatin-modifying complex, and the proper recognition of ligands. NHRs are able to coordinate the expression of genes in numerous pathways simultaneously. This review focuses on the role of nuclear receptors in the central nervous system and, in particular, their role in regulating the proper development and function of the brain and the eye. In addition, the review highlights the impact of mutations in NHRs on a spectrum of human diseases from autism to retinal degeneration.
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Affiliation(s)
- Ana Maria Olivares
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Oscar Andrés Moreno-Ramos
- Departamento de Ciencias Biológicas, Facultad de Ciencias, Universidad de los Andes, Bogotá, Colombia
| | - Neena B Haider
- Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
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34
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Wang MS, Zhang RW, Su LY, Li Y, Peng MS, Liu HQ, Zeng L, Irwin DM, Du JL, Yao YG, Wu DD, Zhang YP. Positive selection rather than relaxation of functional constraint drives the evolution of vision during chicken domestication. Cell Res 2016; 26:556-73. [PMID: 27033669 PMCID: PMC4856766 DOI: 10.1038/cr.2016.44] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Revised: 01/18/2016] [Accepted: 02/22/2016] [Indexed: 01/05/2023] Open
Abstract
As noted by Darwin, chickens have the greatest phenotypic diversity of all birds, but an interesting evolutionary difference between domestic chickens and their wild ancestor, the Red Junglefowl, is their comparatively weaker vision. Existing theories suggest that diminished visual prowess among domestic chickens reflect changes driven by the relaxation of functional constraints on vision, but the evidence identifying the underlying genetic mechanisms responsible for this change has not been definitively characterized. Here, a genome-wide analysis of the domestic chicken and Red Junglefowl genomes showed significant enrichment for positively selected genes involved in the development of vision. There were significant differences between domestic chickens and their wild ancestors regarding the level of mRNA expression for these genes in the retina. Numerous additional genes involved in the development of vision also showed significant differences in mRNA expression between domestic chickens and their wild ancestors, particularly for genes associated with phototransduction and photoreceptor development, such as RHO (rhodopsin), GUCA1A, PDE6B and NR2E3. Finally, we characterized the potential role of the VIT gene in vision, which experienced positive selection and downregulated expression in the retina of the village chicken. Overall, our results suggest that positive selection, rather than relaxation of purifying selection, contributed to the evolution of vision in domestic chickens. The progenitors of domestic chickens harboring weaker vision may have showed a reduced fear response and vigilance, making them easier to be unconsciously selected and/or domesticated.
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Affiliation(s)
- Ming-Shan Wang
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Rong-wei Zhang
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ling-Yan Su
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming, Yunnan 650223, China
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Yan Li
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Min-Sheng Peng
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - He-Qun Liu
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Lin Zeng
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - David M Irwin
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
- Banting and Best Diabetes Centre, University of Toronto, Toronto, Canada
| | - Jiu-Lin Du
- Institute of Neuroscience and State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yong-Gang Yao
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming, Yunnan 650223, China
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
| | - Dong-Dong Wu
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming, Yunnan 650223, China
| | - Ya-Ping Zhang
- State Key Laboratory of Genetic Resources and Evolution, Yunnan Laboratory of Molecular Biology of Domestic Animals
- Kunming College of Life Science, Unisversity of Chinese Academy of Sciences, Kunming, Yunnan 650204, China
- Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming, Yunnan 650091, China
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35
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Mo A, Luo C, Davis FP, Mukamel EA, Henry GL, Nery JR, Urich MA, Picard S, Lister R, Eddy SR, Beer MA, Ecker JR, Nathans J. Epigenomic landscapes of retinal rods and cones. eLife 2016; 5:e11613. [PMID: 26949250 PMCID: PMC4798964 DOI: 10.7554/elife.11613] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/18/2016] [Indexed: 12/28/2022] Open
Abstract
Rod and cone photoreceptors are highly similar in many respects but they have important functional and molecular differences. Here, we investigate genome-wide patterns of DNA methylation and chromatin accessibility in mouse rods and cones and correlate differences in these features with gene expression, histone marks, transcription factor binding, and DNA sequence motifs. Loss of NR2E3 in rods shifts their epigenomes to a more cone-like state. The data further reveal wide differences in DNA methylation between retinal photoreceptors and brain neurons. Surprisingly, we also find a substantial fraction of DNA hypo-methylated regions in adult rods that are not in active chromatin. Many of these regions exhibit hallmarks of regulatory regions that were active earlier in neuronal development, suggesting that these regions could remain undermethylated due to the highly compact chromatin in mature rods. This work defines the epigenomic landscapes of rods and cones, revealing features relevant to photoreceptor development and function. DOI:http://dx.doi.org/10.7554/eLife.11613.001 Vision in humans is made possible by a light-sensing sheet of cells at the back of the eye called the retina. The surface of the retina is populated by specialized sensory cells, known as rods and cones. The rod cells detect very dim light, while the cones are less sensitive to light but are used to detect color. Together, the rods and cones gather the information needed to create a picture that is then transmitted to the brain. Rods and cones have been studied for decades, and genetic analyses have revealed the patterns of gene expression that lead a cell to develop into either a rod or a cone. Researchers have also identified several key regulatory genes that control these patterns, but less is known about the role of other factors that control the expression of genes. Chemical modifications to DNA or modifications to the proteins associated with DNA – which are collectively called epigenetic modifications – can either promote or inhibit the activation of nearby genes. Now, Mo et al. have shown that rods and cones from mice have very different patterns of epigenetic modifications. The experiments also revealed that many sections of DNA that are marked to promote gene activation contain known rod-specific or cone-specific genes; and that rod cells need a known regulatory gene to develop their specific pattern of epigenetic modifications. Finally, Mo et al. showed that epigenetic regulation differed between brain cells and rods and cones. These insights into epigenetic regulation of rod and cone genes may help explain why some people with eye diseases caused by the same genetic mutation may develop symptoms at different ages or lose vision at different rates. The new information about gene regulation may also help scientists to reprogram stem cells to become healthy rods or cones that could be transplanted into people with eye disease to restore their vision. DOI:http://dx.doi.org/10.7554/eLife.11613.002
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Affiliation(s)
- Alisa Mo
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Chongyuan Luo
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, United States
| | - Fred P Davis
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Eran A Mukamel
- Department of Cognitive Science, University of California San Diego, La Jolla, United States
| | - Gilbert L Henry
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Joseph R Nery
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States
| | - Mark A Urich
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States
| | - Serge Picard
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Ryan Lister
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, Australia
| | - Sean R Eddy
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Michael A Beer
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, United States
| | - Joseph R Ecker
- Genomic Analysis Laboratory, The Salk Institute for Biological Studies, La Jolla, United States.,Howard Hughes Medical Institute, The Salk Institute for Biological Studies, La Jolla, United States
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, United States.,Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, United States
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36
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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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37
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Kostic C, Arsenijevic Y. Animal modelling for inherited central vision loss. J Pathol 2015; 238:300-10. [PMID: 26387748 PMCID: PMC5063185 DOI: 10.1002/path.4641] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 09/02/2015] [Accepted: 09/16/2015] [Indexed: 01/01/2023]
Abstract
Disease-causing variants of a large number of genes trigger inherited retinal degeneration leading to photoreceptor loss. Because cones are essential for daylight and central vision such as reading, mobility, and face recognition, this review focuses on a variety of animal models for cone diseases. The pertinence of using these models to reveal genotype/phenotype correlations and to evaluate new therapeutic strategies is discussed. Interestingly, several large animal models recapitulate human diseases and can serve as a strong base from which to study the biology of disease and to assess the scale-up of new therapies. Examples of innovative approaches will be presented such as lentiviral-based transgenesis in pigs and adeno-associated virus (AAV)-gene transfer into the monkey eye to investigate the neural circuitry plasticity of the visual system. The models reported herein permit the exploration of common mechanisms that exist between different species and the identification and highlighting of pathways that may be specific to primates, including humans.
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Affiliation(s)
- Corinne Kostic
- Unit of Gene Therapy and Stem Cell Biology, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, University of Lausanne, Switzerland
| | - Yvan Arsenijevic
- Unit of Gene Therapy and Stem Cell Biology, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, University of Lausanne, Switzerland
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38
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Moreno-Ramos OA, Olivares AM, Haider NB, de Autismo LC, Lattig MC. Whole-Exome Sequencing in a South American Cohort Links ALDH1A3, FOXN1 and Retinoic Acid Regulation Pathways to Autism Spectrum Disorders. PLoS One 2015; 10:e0135927. [PMID: 26352270 PMCID: PMC4564166 DOI: 10.1371/journal.pone.0135927] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 07/28/2015] [Indexed: 12/20/2022] Open
Abstract
Autism spectrum disorders (ASDs) are a range of complex neurodevelopmental conditions principally characterized by dysfunctions linked to mental development. Previous studies have shown that there are more than 1000 genes likely involved in ASD, expressed mainly in brain and highly interconnected among them. We applied whole exome sequencing in Colombian—South American trios. Two missense novel SNVs were found in the same child: ALDH1A3 (RefSeq NM_000693: c.1514T>C (p.I505T)) and FOXN1 (RefSeq NM_003593: c.146C>T (p.S49L)). Gene expression studies reveal that Aldh1a3 and Foxn1 are expressed in ~E13.5 mouse embryonic brain, as well as in adult piriform cortex (PC; ~P30). Conserved Retinoic Acid Response Elements (RAREs) upstream of human ALDH1A3 and FOXN1 and in mouse Aldh1a3 and Foxn1 genes were revealed using bioinformatic approximation. Chromatin immunoprecipitation (ChIP) assay using Retinoid Acid Receptor B (Rarb) as the immunoprecipitation target suggests RA regulation of Aldh1a3 and Foxn1 in mice. Our results frame a possible link of RA regulation in brain to ASD etiology, and a feasible non-additive effect of two apparently unrelated variants in ALDH1A3 and FOXN1 recognizing that every result given by next generation sequencing should be cautiously analyzed, as it might be an incidental finding.
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Affiliation(s)
- Oscar A. Moreno-Ramos
- Departamento de Ciencias Biológicas, Facultad de Ciencias, Universidad de los Andes, Bogotá D.C., Colombia
| | - Ana María Olivares
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | - Neena B. Haider
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, MA, United States of America
| | | | - María Claudia Lattig
- Departamento de Ciencias Biológicas, Facultad de Ciencias, Universidad de los Andes, Bogotá D.C., Colombia
- * E-mail:
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39
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German OL, Agnolazza DL, Politi LE, Rotstein NP. Light, lipids and photoreceptor survival: live or let die? Photochem Photobiol Sci 2015. [PMID: 26204250 DOI: 10.1039/c5pp00194c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Due to its constant exposure to light and its high oxygen consumption the retina is highly sensitive to oxidative damage, which is a common factor in inducing the death of photoreceptors after light damage or in inherited retinal degenerations. The high content of docosahexaenoic acid (DHA), the major polyunsaturated fatty acid in the retina, has been suggested to contribute to this sensitivity. DHA is crucial for developing and preserving normal visual function. However, further roles of DHA in the retina are still controversial. Current data support that it can tilt the scale either towards degeneration or survival of retinal cells. DHA peroxidation products can be deleterious to the retina and might lead to retinal degeneration. However, DHA has also been shown to act as, or to be the source of, a survival molecule that protects photoreceptors and retinal pigment epithelium cells from oxidative damage. We have established that DHA protects photoreceptors from oxidative stress-induced apoptosis and promotes their differentiation in vitro. DHA activates the retinoid X receptor (RXR) and the ERK/MAPK pathway, thus regulating the expression of anti and pro-apoptotic proteins. It also orchestrates a diversity of signaling pathways, modulating enzymatic pathways that control the sphingolipid metabolism and activate antioxidant defense mechanisms to promote photoreceptor survival and development. A deeper comprehension of DHA signaling pathways and context-dependent behavior is required to understand its dual functions in retinal physiology.
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Affiliation(s)
- Olga Lorena German
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Universidad Nacional del Sur (UNS)-CONICET, Bahía Blanca, Buenos Aires, Argentina.
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40
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Khanal T, Kim D, Johnson A, Choubey D, Kim K. Deregulation of NR2E3, an orphan nuclear receptor, by benzo(a)pyrene-induced oxidative stress is associated with histone modification status change of the estrogen receptor gene promoter. Toxicol Lett 2015; 237:228-36. [PMID: 26149760 DOI: 10.1016/j.toxlet.2015.06.1708] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 06/05/2015] [Accepted: 06/22/2015] [Indexed: 10/23/2022]
Abstract
We previously reported that NR2E3, an orphan nuclear receptor, plays an important role in maintaining the basal expression of estrogen receptor α (ER) and that the NR2E3 level is highly correlated with the relapse-free survival of breast cancer patients. Here, we investigated the role of NR2E3 in benzo(a)pyrene (BaP)-mediated cell injury. BaP treatment reduced NR2E3 homo-dimer formation and expression and subsequently decreased ER expression. The chromatin immunoprecipitation assay results showed that the treatment of MCF-7 breast cancer cells and the mouse liver with BaP released NR2E3 from the ER promoter to transform the transcriptionally active histone modification status into a repressive state. NR2E3 depletion in MCF-7 cells also induced a similar inactive epigenetic status in the ER promoter region, indicating that NR2E3 is an essential epigenetic player that maintains basal ER expression. Interestingly, these negative effects of BaP on the expression levels of NR2E3 and ER were rescued by antioxidant treatment. Collectively, our study provides novel evidence to show that BaP-induced oxidative stress decreases ER expression, in part by regulating NR2E3 function, which modulates the epigenetic status of the ER promoter. NR2E3 is likely an essential epigenetic player that maintains basal ER expression to protect cells from BaP-induced oxidative injury.
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Affiliation(s)
- Tilak Khanal
- Department of Environmental Health, University of Cincinnati, College of Medicine, 160 Panzeca way, Cincinnati, OH 45267, USA
| | - Dasom Kim
- Department of Environmental Health, University of Cincinnati, College of Medicine, 160 Panzeca way, Cincinnati, OH 45267, USA
| | - Abby Johnson
- Department of Environmental Health, University of Cincinnati, College of Medicine, 160 Panzeca way, Cincinnati, OH 45267, USA
| | - Divaker Choubey
- Department of Environmental Health, University of Cincinnati, College of Medicine, 160 Panzeca way, Cincinnati, OH 45267, USA
| | - Kyounghyun Kim
- Department of Environmental Health, University of Cincinnati, College of Medicine, 160 Panzeca way, Cincinnati, OH 45267, USA.
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41
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Krol J, Krol I, Alvarez CPP, Fiscella M, Hierlemann A, Roska B, Filipowicz W. A network comprising short and long noncoding RNAs and RNA helicase controls mouse retina architecture. Nat Commun 2015; 6:7305. [PMID: 26041499 PMCID: PMC4468907 DOI: 10.1038/ncomms8305] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 04/27/2015] [Indexed: 12/25/2022] Open
Abstract
Brain regions, such as the cortex and retina, are composed of layers of uniform thickness. The molecular mechanism that controls this uniformity is not well understood. Here we show that during mouse postnatal development the timed expression of Rncr4, a retina-specific long noncoding RNA, regulates the similarly timed processing of pri-miR-183/96/182, which is repressed at an earlier developmental stage by RNA helicase Ddx3x. Shifting the timing of mature miR-183/96/182 accumulation or interfering with Ddx3x expression leads to the disorganization of retinal architecture, with the photoreceptor layer being most affected. We identify Crb1, a component of the adhesion belt between glial and photoreceptor cells, as a link between Rncr4-regulated miRNA metabolism and uniform retina layering. Our results suggest that the precise timing of glia–neuron interaction controlled by noncoding RNAs and Ddx3x is important for the even distribution of cells across layers. The mammalian retina is a modular brain region, in which cell layers are of uniform thickness but the molecular mechanism controlling this process is not well understood. Here the authors identify a regulatory network consisting of the long noncoding RNA Rncr4, RNA helicase Ddx3x and miR-183/96/182 that controls the even distribution of cells across layers.
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Affiliation(s)
- Jacek Krol
- Neural Circuit Laboratories, Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Ilona Krol
- Neural Circuit Laboratories, Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | | | | | | | - Botond Roska
- 1] Neural Circuit Laboratories, Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland [2] Faculty of Medicine, University of Basel, 4056 Basel, Switzerland
| | - Witold Filipowicz
- 1] Neural Circuit Laboratories, Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland [2] Biozentrum, University of Basel, 4056 Basel, Switzerland
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42
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von Alpen D, Tran HV, Guex N, Venturini G, Munier FL, Schorderet DF, Haider NB, Escher P. Differential dimerization of variants linked to enhanced S-cone sensitivity syndrome (ESCS) located in the NR2E3 ligand-binding domain. Hum Mutat 2015; 36:599-610. [PMID: 25703721 DOI: 10.1002/humu.22775] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 02/10/2015] [Indexed: 11/11/2022]
Abstract
NR2E3 encodes the photoreceptor-specific nuclear hormone receptor that acts as a repressor of cone-specific gene expression in rod photoreceptors, and as an activator of several rod-specific genes. Recessive variants located in the ligand-binding domain (LBD) of NR2E3 cause enhanced short wavelength sensitive- (S-) cone syndrome (ESCS), a retinal degeneration characterized by an excess of S-cones and non-functional rods. We analyzed the dimerization properties of NR2E3 and the effect of disease-causing LBD missense variants by bioluminescence resonance energy transfer (BRET(2) ) protein interaction assays. Homodimerization was not affected in presence of p.A256V, p.R039G, p.R311Q, and p.R334G variants, but abolished in presence of p.L263P, p.L336P, p.L353V, p.R385P, and p.M407K variants. Homology modeling predicted structural changes induced by NR2E3 LBD variants. NR2E3 LBD variants did not affect interaction with CRX, but with NRL and rev-erbα/NR1D1. CRX and NRL heterodimerized more efficiently together, than did either with NR2E3. NR2E3 did not heterodimerize with TLX/NR2E1 and RXRα/NR2C1. The identification of a new compound heterozygous patient with detectable rod function, who expressed solely the p.A256V variant protein, suggests a correlation between LBD variants able to form functional NR2E3 dimers and atypical mild forms of ESCS with residual rod function.
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Affiliation(s)
- Désirée von Alpen
- IRO-Institute for Research in Ophthalmology, Sion, Switzerland.,EPFL-Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Hoai Viet Tran
- Jules-Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland
| | - Nicolas Guex
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | | | - Francis L Munier
- Jules-Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland
| | - Daniel F Schorderet
- IRO-Institute for Research in Ophthalmology, Sion, Switzerland.,EPFL-Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,Jules-Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland
| | - Neena B Haider
- Department of Ophthalmology, Harvard Medical School, Schepens Eye Research Institute, Boston, Massachusetts
| | - Pascal Escher
- IRO-Institute for Research in Ophthalmology, Sion, Switzerland.,Jules-Gonin Eye Hospital, University of Lausanne, Lausanne, Switzerland
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43
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Bates KE, Molnar J, Robinow S. The unfulfilled gene and nervous system development in Drosophila. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:217-23. [PMID: 24953188 DOI: 10.1016/j.bbagrm.2014.06.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 06/07/2014] [Accepted: 06/10/2014] [Indexed: 11/29/2022]
Abstract
The unfulfilled gene of Drosophila encodes a member of the NR2E subfamily of nuclear receptors. Like related members of the NR2E subfamily, UNFULFILLED is anticipated to function as a dimer, binding to DNA response elements and regulating the expression of target genes. The UNFULFILLED protein may be regulated by ligand-binding and may also be post-transcriptionally modified by sumoylation and phosphorylation. unfulfilled mutants display a range of aberrant phenotypes, problems with eclosion and post-eclosion behaviors, compromised fertility, arrhythmicity, and a lack of all adult mushroom body lobes. The locus of the fertility problem has not been determined. The behavioral arrhythmicity is due to the unfulfilled-dependent disruption of gene expression in a set of pacemaker neurons. The eclosion and the mushroom body lobe phenotypes of unfulfilled mutants are the result of developmental problems associated with failures in axon pathfinding or re-extension. Interest in genes that act downstream of unfulfilled has resulted in the identification of a growing number of unfulfilled interacting loci, providing the first glimpse into the composition of unfulfilled-dependent gene networks. This article is part of a Special Issue entitled: Nuclear receptors in animal development.
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Affiliation(s)
- Karen E Bates
- Department of Biology, University of Hawaii, Honolulu, HI 96822, USA
| | - Janos Molnar
- Department of Biology, University of Hawaii, Honolulu, HI 96822, USA
| | - Steven Robinow
- Department of Biology, University of Hawaii, Honolulu, HI 96822, USA.
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44
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Modifier genes as therapeutics: the nuclear hormone receptor Rev Erb alpha (Nr1d1) rescues Nr2e3 associated retinal disease. PLoS One 2014; 9:e87942. [PMID: 24498227 PMCID: PMC3909326 DOI: 10.1371/journal.pone.0087942] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 12/30/2013] [Indexed: 11/19/2022] Open
Abstract
Nuclear hormone receptors play a major role in many important biological processes. Most nuclear hormone receptors are ubiquitously expressed and regulate processes such as metabolism, circadian function, and development. They function in these processes to maintain homeostasis through modulation of transcriptional gene networks. In this study we evaluate the effectiveness of a nuclear hormone receptor gene to modulate retinal degeneration and restore the integrity of the retina. Currently, there are no effective treatment options for retinal degenerative diseases leading to progressive and irreversible blindness. In this study we demonstrate that the nuclear hormone receptor gene Nr1d1 (Rev-Erbα) rescues Nr2e3-associated retinal degeneration in the rd7 mouse, which lacks a functional Nr2e3 gene. Mutations in human NR2E3 are associated with several retinal degenerations including enhanced S cone syndrome and retinitis pigmentosa. The rd7 mouse, lacking Nr2e3, exhibits an increase in S cones and slow, progressive retinal degeneration. A traditional genetic mapping approach previously identified candidate modifier loci. Here, we demonstrate that in vivo delivery of the candidate modifier gene, Nr1d1 rescues Nr2e3 associated retinal degeneration. We observed clinical, histological, functional, and molecular restoration of the rd7 retina. Furthermore, we demonstrate that the mechanism of rescue at the molecular and functional level is through the re-regulation of key genes within the Nr2e3-directed transcriptional network. Together, these findings reveal the potency of nuclear receptors as modulators of disease and specifically of NR1D1 as a novel therapeutic for retinal degenerations.
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45
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Park SP, Hong IH, Tsang SH, Lee W, Horowitz J, Yzer S, Allikmets R, Chang S. Disruption of the human cone photoreceptor mosaic from a defect in NR2E3 transcription factor function in young adults. Graefes Arch Clin Exp Ophthalmol 2013; 251:2299-309. [PMID: 23604511 PMCID: PMC4291322 DOI: 10.1007/s00417-013-2296-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 02/19/2013] [Accepted: 02/24/2013] [Indexed: 10/26/2022] Open
Abstract
BACKGROUND Enhanced S-cone syndrome is an orphan disease caused by mutations in the NR2E3 gene which result in an increased number of S-cones overpopulating the retina. Although the characteristic onset of enhanced S-cone syndrome can be well-documented by current ophthalmic imaging modalities, techniques such as spectral-domain optical coherence tomography (SD-OCT) and scanning laser ophthalmoscopy (SLO) fail to provide sufficient details regarding the microstructure of photoreceptors in retinal diseases. Adaptive optics (AO) provides a unique opportunity to analyze the effects of genetic mutations on photoreceptors by compensating aberrations of human eyes. METHODS Three eyes of three young adults with enhanced S-cone syndrome were studied by clinical examination, genetic screening, fundus autofluorescence (FAF) imaging, SD-OCT, and electroretinography (ERG). Cone mosaic imaging was accomplished by an AO-SLO equipped with a dual crystal on silicon spatial light modulator. Qualitative image analyses and genetic findings were investigated in each patient. RESULTS The diagnosis of patients was confirmed by ERG finding. Genetic screening confirmed the presence of two disease-causing mutations in the NR2E3 gene in each study patient, as well as identified a novel mutation (202 A > G, S68G). Fundus photograph, FAF, and SD-OCT found rosette-like lesion within the mid-periphery along the vascular arcades of the retina. In all AO-SLO images of patients, sparse distribution and asymmetric size of cone mosaic pattern were found within central retina. There were regions of dark space between groups of photoreceptors, distinguishable from shadowing and artifacts. CONCLUSIONS AO-SLO provided an in-depth window into the retina of live enhanced S-cone syndrome patients beyond the ability of other current imaging modalities. Dark lesions within the central retina in each patient contain structurally dysfunctional cones which account for retinal mosaic disorganization, and may predispose affected areas to other abnormalities such as rosette lesions. AO-SLO can be an efficient diagnostic tool in clinics for examining cellular-level pathologies in various retinal dystrophies.
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Affiliation(s)
- Sung Pyo Park
- Department of Ophthalmology, Columbia University, New York, NY, USA
- Department of Ophthalmology, Kangdong Sacred Heart Hospital, Hallym University Medical Center, Seoul, South Korea
| | - In Hwan Hong
- Department of Ophthalmology, Kangdong Sacred Heart Hospital, Hallym University Medical Center, Seoul, South Korea
| | - Stephen H. Tsang
- Department of Ophthalmology, Columbia University, New York, NY, USA
- Department of Pathology & Cell Biology, Columbia University, New York, NY, USA
- Departments of Ophthalmology, Pathology and Cell Biology, Edward S. Harkness Eye Institute, Columbia University, 635 west 165th street, New York, NY 10032, USA
| | - Winston Lee
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Jason Horowitz
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | | | - Rando Allikmets
- Department of Ophthalmology, Columbia University, New York, NY, USA
- Department of Pathology & Cell Biology, Columbia University, New York, NY, USA
| | - Stanley Chang
- Department of Ophthalmology, Columbia University, New York, NY, USA
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46
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Tan MHE, Zhou XE, Soon FF, Li X, Li J, Yong EL, Melcher K, Xu HE. The crystal structure of the orphan nuclear receptor NR2E3/PNR ligand binding domain reveals a dimeric auto-repressed conformation. PLoS One 2013; 8:e74359. [PMID: 24069298 PMCID: PMC3771917 DOI: 10.1371/journal.pone.0074359] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 07/31/2013] [Indexed: 01/20/2023] Open
Abstract
Photoreceptor-specific nuclear receptor (PNR, NR2E3) is a key transcriptional regulator of human photoreceptor differentiation and maintenance. Mutations in the NR2E3-encoding gene cause various retinal degenerations, including Enhanced S-cone syndrome, retinitis pigmentosa, and Goldman-Favre disease. Although physiological ligands have not been identified, it is believed that binding of small molecule agonists, receptor desumoylation, and receptor heterodimerization may switch NR2E3 from a transcriptional repressor to an activator. While these features make NR2E3 a potential therapeutic target for the treatment of retinal diseases, there has been a clear lack of structural information for the receptor. Here, we report the crystal structure of the apo NR2E3 ligand binding domain (LBD) at 2.8 Å resolution. Apo NR2E3 functions as transcriptional repressor in cells and the structure of its LBD is in a dimeric auto-repressed conformation. In this conformation, the putative ligand binding pocket is filled with bulky hydrophobic residues and the activation-function-2 (AF2) helix occupies the canonical cofactor binding site. Mutations designed to disrupt either the AF2/cofactor-binding site interface or the dimer interface compromised the transcriptional repressor activity of this receptor. Together, these results reveal several conserved structural features shared by related orphan nuclear receptors, suggest that most disease-causing mutations affect the receptor's structural integrity, and allowed us to model a putative active conformation that can accommodate small ligands in its pocket.
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Affiliation(s)
- M. H. Eileen Tan
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Department of Obstetrics & Gynecology, National University Hospital, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - X. Edward Zhou
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
| | - Fen-Fen Soon
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Department of Obstetrics & Gynecology, National University Hospital, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xiaodan Li
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Key Laboratory of Regenerative Biology, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Jun Li
- Department of Obstetrics & Gynecology, National University Hospital, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Eu-Leong Yong
- Department of Obstetrics & Gynecology, National University Hospital, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Karsten Melcher
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
| | - H. Eric Xu
- Laboratory of Structural Sciences, Van Andel Research Institute, Grand Rapids, Michigan, United States of America
- Van Andel Research Institute/Shanghai Institute of Materia Medica Center, Chinese Academy of Sciences-Key Laboratory of Receptor Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
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47
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Hennig AK, Peng GH, Chen S. Transcription coactivators p300 and CBP are necessary for photoreceptor-specific chromatin organization and gene expression. PLoS One 2013; 8:e69721. [PMID: 23922782 PMCID: PMC3724885 DOI: 10.1371/journal.pone.0069721] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 06/12/2013] [Indexed: 12/12/2022] Open
Abstract
Rod and cone photoreceptor neurons in the mammalian retina possess specialized cellular architecture and functional features for converting light to a neuronal signal. Establishing and maintaining these characteristics requires appropriate expression of a specific set of genes, which is tightly regulated by a network of photoreceptor transcription factors centered on the cone-rod homeobox protein CRX. CRX recruits transcription coactivators p300 and CBP to acetylate promoter-bound histones and activate transcription of target genes. To further elucidate the role of these two coactivators, we conditionally knocked out Ep300 and/or CrebBP in differentiating rods or cones, using opsin-driven Cre recombinase. Knockout of either factor alone exerted minimal effects, but loss of both factors severely disrupted target cell morphology and function: the unique nuclear chromatin organization seen in mouse rods was reversed, accompanied by redistribution of nuclear territories associated with repressive and active histone marks. Transcription of many genes including CRX targets was severely impaired, correlating with reduced histone H3/H4 acetylation (the products of p300/CBP) on target gene promoters. Interestingly, the presence of a single wild-type allele of either coactivator prevented many of these defects, with Ep300 more effective than Cbp. These results suggest that p300 and CBP play essential roles in maintaining photoreceptor-specific structure, function and gene expression.
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Affiliation(s)
- Anne K. Hennig
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Guang-Hua Peng
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Shiming Chen
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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48
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Wang NK, Lai CC, Liu CH, Yeh LK, Chou CL, Kong J, Nagasaki T, Tsang SH, Chien CL. Origin of fundus hyperautofluorescent spots and their role in retinal degeneration in a mouse model of Goldmann-Favre syndrome. Dis Model Mech 2013; 6:1113-22. [PMID: 23828046 PMCID: PMC3759331 DOI: 10.1242/dmm.012112] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Goldmann-Favre syndrome, also known as enhanced S-cone syndrome, is an inherited retinal degeneration disease in which a gain of photoreceptor cell types results in retinal dysplasia and degeneration. Although microglia have been implicated in the pathogenesis of many neurodegenerative diseases, the fundamental role of these cells in this disease is unknown. In the current study, sequential analyses suggest that microglia are recruited and appear after outer nuclear layer folding. By crossing rd7 mice (a model for hereditary retinal degeneration owing to Nr2e3 mutation) with mice carrying the macrophage Fas-induced apoptosis (Mafia) transgene, we generated double-mutant mice and studied the role of the resident retinal microglia. Microglial cells in these double-mutant mice express enhanced green fluorescent protein (EGFP) and a suicide gene that can trigger Fas-mediated apoptosis via systemic treatment with AP20187 (FK506 dimerizer). We demonstrated that more than 80% of the EGFP+ cells in retinas from rd7/rd7;Tg/Tg mice express Iba-1 (a microglial marker), and resident microglia are still present in the retina because AP20187 does not cross the blood-brain barrier. Hence, only circulating bone marrow (BM)-derived microglia are depleted. Depletion of circulating BM-derived microglia accelerates retinal degeneration in rd7 mice. An increased number of autofluorescent (AF) spots is a consequence of resident microglia proliferation, which in turn establishes an inflammatory cytokine milieu via the upregulation of IL-1β, IL-6 and TNFα expression. This inflammation is likely to accelerate retinal degeneration. This study not only identifies inflammation as a crucial step in the pathogenesis of retinal degeneration, but also highlights the involvement of specific cytokine genes that could serve as future treatment targets in retinal degenerations.
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Affiliation(s)
- Nan-Kai Wang
- Department of Anatomy and Cell Biology, National Taiwan University, Taipei 100, Taiwan
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49
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Liu MM, Zack DJ. Alternative splicing and retinal degeneration. Clin Genet 2013; 84:142-9. [PMID: 23647439 DOI: 10.1111/cge.12181] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 04/30/2013] [Accepted: 04/30/2013] [Indexed: 12/27/2022]
Abstract
Alternative splicing is highly regulated in tissue-specific and development-specific patterns, and it has been estimated that 15% of disease-causing point mutations affect pre-mRNA splicing. In this review, we consider the cis-acting splice site and trans-acting splicing factor mutations that affect pre-mRNA splicing and contribute to retinal degeneration. Numerous splice site mutations have been identified in retinitis pigmentosa (RP) and various cone-rod dystrophies. Mutations in alternatively spliced retina-specific exons of the widely expressed RPGR and COL2A1 genes lead primarily to X-linked RP and ocular variants of Stickler syndrome, respectively. Furthermore, mutations in general pre-mRNA splicing factors, such as PRPF31, PRPF8, and PRPF3, predominantly cause autosomal dominant RP. These findings suggest an important role for pre-mRNA splicing in retinal homeostasis and the pathogenesis of retinal degenerative diseases. The development of novel therapeutic strategies to modulate aberrant splicing, including small molecule-based therapies, has the potential to lead to new treatments for retinal degenerative diseases.
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Affiliation(s)
- M M Liu
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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50
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Riera M, Burguera D, Garcia-Fernàndez J, Gonzàlez-Duarte R. CERKL knockdown causes retinal degeneration in zebrafish. PLoS One 2013; 8:e64048. [PMID: 23671706 PMCID: PMC3650063 DOI: 10.1371/journal.pone.0064048] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 04/08/2013] [Indexed: 12/21/2022] Open
Abstract
The human CERKL gene is responsible for common and severe forms of retinal dystrophies. Despite intense in vitro studies at the molecular and cellular level and in vivo analyses of the retina of murine knockout models, CERKL function remains unknown. In this study, we aimed to approach the developmental and functional features of cerkl in Danio rerio within an Evo-Devo framework. We show that gene expression increases from early developmental stages until the formation of the retina in the optic cup. Unlike the high mRNA-CERKL isoform multiplicity shown in mammals, the moderate transcriptional complexity in fish facilitates phenotypic studies derived from gene silencing. Moreover, of relevance to pathogenicity, teleost CERKL shares the two main human protein isoforms. Morpholino injection has been used to generate a cerkl knockdown zebrafish model. The morphant phenotype results in abnormal eye development with lamination defects, failure to develop photoreceptor outer segments, increased apoptosis of retinal cells and small eyes. Our data support that zebrafish Cerkl does not interfere with proliferation and neural differentiation during early developmental stages but is relevant for survival and protection of the retinal tissue. Overall, we propose that this zebrafish model is a powerful tool to unveil CERKL contribution to human retinal degeneration.
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Affiliation(s)
- Marina Riera
- Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBERER, Instituto de Salud Carlos III, Barcelona, Spain
| | - Demian Burguera
- Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Jordi Garcia-Fernàndez
- Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Roser Gonzàlez-Duarte
- Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain
- Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- CIBERER, Instituto de Salud Carlos III, Barcelona, Spain
- * E-mail:
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