1
|
Takahashi K, Sudharsan R, Beltran WA. Mapping protein distribution in the canine photoreceptor sensory cilium and calyceal processes by ultrastructure expansion microscopy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.27.600953. [PMID: 38979372 PMCID: PMC11230445 DOI: 10.1101/2024.06.27.600953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Photoreceptors are highly polarized sensory neurons, possessing a unique ciliary structure known as the photoreceptor sensory cilium (PSC). Vertebrates have two subtypes of photoreceptors: rods, which are responsible for night vision, and cones, which support daylight vision and color perception. Despite identifying functional and morphological differences between these subtypes, ultrastructural analyses of the PSC molecular architecture in rods and cones are still lacking. In this study, we employed ultrastructure expansion microscopy (U-ExM) to characterize the molecular architecture of the PSC in canine retina. We demonstrated that U-ExM is applicable to both non-frozen and cryopreserved retinal tissues with standard paraformaldehyde fixation. Using this validated U-ExM protocol, we revealed the molecular localization of numerous ciliopathy-related proteins in canine photoreceptors. Furthermore, we identified significant architectural differences in the PSC, ciliary rootlet, and calyceal processes between canine rods and cones. These findings pave the way for a better understanding of alterations in the molecular architecture of the PSC in canine models of retinal ciliopathies.
Collapse
Affiliation(s)
- Kei Takahashi
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Raghavi Sudharsan
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - William A. Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| |
Collapse
|
2
|
Vrabič N, Fakin A, Tekavčič Pompe M. Spectrum and frequencies of extraocular features reported in CEP290-associated ciliopathy - A systematic review. J Fr Ophtalmol 2024; 47:104232. [PMID: 39213781 DOI: 10.1016/j.jfo.2024.104232] [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: 09/27/2023] [Revised: 12/22/2023] [Accepted: 01/22/2024] [Indexed: 09/04/2024]
Abstract
Pathogenic variants in the CEP290 gene may result in a broad spectrum of diseases, ranging from lethal neonatal syndromes to isolated retinopathy. A detailed review of the clinical spectrum with the incidence of affected extraocular systems has not yet been published. A review of published papers was carried out to provide a comprehensive report on systemic signs and symptoms associated with CEP290 ciliopathies and to explore the genotype-phenotype correlation. Genetic and clinical data were collected on patients with biallelic variants in the CEP290 gene and the extraocular tissues affected. Genotype-phenotype analysis was performed. Two hundred thirty-five patients were included in the analysis. The most frequently reported organs affected, after the eye, were the central nervous system (82.6%, 194/235), followed by the kidney (53.2%, 125/235), skeletal system (15.3% 36/235), and a large spectrum of other, less frequently reported clinical manifestations. Patients with two variants that together predictably resulted in a low amount of CEP290 protein showed a significant association with having two or more extraocular organ systems affected. This is the most extensive report to date on patients with CEP290-ciliopathy and affected extraocular tissues. Based on these findings and previous publications, systemic screening is proposed, together with a clinical pathway for patients with CEP290-related ciliopathy.
Collapse
Affiliation(s)
- N Vrabič
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia
| | - A Fakin
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia
| | - M Tekavčič Pompe
- Eye Hospital, University Medical Centre Ljubljana, Grablovičeva 46, 1000 Ljubljana, Slovenia; Faculty of Medicine, University of Ljubljana, Vrazov trg 2, 1000 Ljubljana, Slovenia.
| |
Collapse
|
3
|
Kurzawa-Akanbi M, Tzoumas N, Corral-Serrano JC, Guarascio R, Steel DH, Cheetham ME, Armstrong L, Lako M. Pluripotent stem cell-derived models of retinal disease: Elucidating pathogenesis, evaluating novel treatments, and estimating toxicity. Prog Retin Eye Res 2024; 100:101248. [PMID: 38369182 DOI: 10.1016/j.preteyeres.2024.101248] [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: 12/07/2023] [Revised: 02/13/2024] [Accepted: 02/14/2024] [Indexed: 02/20/2024]
Abstract
Blindness poses a growing global challenge, with approximately 26% of cases attributed to degenerative retinal diseases. While gene therapy, optogenetic tools, photosensitive switches, and retinal prostheses offer hope for vision restoration, these high-cost therapies will benefit few patients. Understanding retinal diseases is therefore key to advance effective treatments, requiring in vitro models replicating pathology and allowing quantitative assessments for drug discovery. Pluripotent stem cells (PSCs) provide a unique solution given their limitless supply and ability to differentiate into light-responsive retinal tissues encompassing all cell types. This review focuses on the history and current state of photoreceptor and retinal pigment epithelium (RPE) cell generation from PSCs. We explore the applications of this technology in disease modelling, experimental therapy testing, biomarker identification, and toxicity studies. We consider challenges in scalability, standardisation, and reproducibility, and stress the importance of incorporating vasculature and immune cells into retinal organoids. We advocate for high-throughput automation in data acquisition and analyses and underscore the value of advanced micro-physiological systems that fully capture the interactions between the neural retina, RPE, and choriocapillaris.
Collapse
|
4
|
Zhang Z, Moye AR, He F, Chen M, Agosto MA, Wensel TG. Centriole and transition zone structures in photoreceptor cilia revealed by cryo-electron tomography. Life Sci Alliance 2024; 7:e202302409. [PMID: 38182160 PMCID: PMC10770417 DOI: 10.26508/lsa.202302409] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 12/12/2023] [Accepted: 12/12/2023] [Indexed: 01/07/2024] Open
Abstract
Primary cilia mediate sensory signaling in multiple organisms and cell types but have structures adapted for specific roles. Structural defects in them lead to devastating diseases known as ciliopathies in humans. Key to their functions are structures at their base: the basal body, the transition zone, the "Y-shaped links," and the "ciliary necklace." We have used cryo-electron tomography with subtomogram averaging and conventional transmission electron microscopy to elucidate the structures associated with the basal region of the "connecting cilia" of rod outer segments in mouse retina. The longitudinal variations in microtubule (MT) structures and the lumenal scaffold complexes connecting them have been determined, as well as membrane-associated transition zone structures: Y-shaped links connecting MT to the membrane, and ciliary beads connected to them that protrude from the cell surface and form a necklace-like structure. These results represent a clearer structural scaffold onto which molecules identified by genetics, proteomics, and superresolution fluorescence can be placed in our emerging model of photoreceptor sensory cilia.
Collapse
Affiliation(s)
- Zhixian Zhang
- https://ror.org/02pttbw34 Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Abigail R Moye
- https://ror.org/02pttbw34 Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
- Department of Ophthalmic Genetics, Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland
| | - Feng He
- https://ror.org/02pttbw34 Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
| | - Muyuan Chen
- https://ror.org/02pttbw34 Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
- Division of CryoEM and Bioimaging, SSRL, SLAC National Accelerator Laboratory, Stanford University, Menlo Park, CA, USA
| | - Melina A Agosto
- Department of Physiology and Biophysics and Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada
| | - Theodore G Wensel
- https://ror.org/02pttbw34 Verna and Marrs McLean Department of Biochemistry and Molecular Pharmacology, Baylor College of Medicine, Houston, TX, USA
| |
Collapse
|
5
|
Haggerty KN, Eshelman SC, Sexton LA, Frimpong E, Rogers LM, Agosto MA, Robichaux MA. Super-resolution mapping in rod photoreceptors identifies rhodopsin trafficking through the inner segment plasma membrane as an essential subcellular pathway. PLoS Biol 2024; 22:e3002467. [PMID: 38190419 PMCID: PMC10773939 DOI: 10.1371/journal.pbio.3002467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 12/10/2023] [Indexed: 01/10/2024] Open
Abstract
Photoreceptor cells in the vertebrate retina have a highly compartmentalized morphology for efficient phototransduction and vision. Rhodopsin, the visual pigment in rod photoreceptors, is densely packaged into the rod outer segment sensory cilium and continuously renewed through essential synthesis and trafficking pathways housed in the rod inner segment. Despite the importance of this region for rod health and maintenance, the subcellular organization of rhodopsin and its trafficking regulators in the mammalian rod inner segment remain undefined. We used super-resolution fluorescence microscopy with optimized retinal immunolabeling techniques to perform a single molecule localization analysis of rhodopsin in the inner segments of mouse rods. We found that a significant fraction of rhodopsin molecules was localized at the plasma membrane, at the surface, in an even distribution along the entire length of the inner segment, where markers of transport vesicles also colocalized. Thus, our results collectively establish a model of rhodopsin trafficking through the inner segment plasma membrane as an essential subcellular pathway in mouse rod photoreceptors.
Collapse
Affiliation(s)
- Kristen N. Haggerty
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Shannon C. Eshelman
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Lauren A. Sexton
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Emmanuel Frimpong
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Leah M. Rogers
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| | - Melina A. Agosto
- Retina and Optic Nerve Research Laboratory, Department of Physiology and Biophysics, and Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Michael A. Robichaux
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, West Virginia, United States of America
| |
Collapse
|
6
|
Cideciyan AV, Jacobson SG, Ho AC, Swider M, Sumaroka A, Roman AJ, Wu V, Russell RC, Viarbitskaya I, Garafalo AV, Schwartz MR, Girach A. Durable vision improvement after a single intravitreal treatment with antisense oligonucleotide in CEP290-LCA: Replication in two eyes. Am J Ophthalmol Case Rep 2023; 32:101873. [PMID: 37388818 PMCID: PMC10302566 DOI: 10.1016/j.ajoc.2023.101873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/15/2023] [Accepted: 06/11/2023] [Indexed: 07/01/2023] Open
Abstract
Purpose An intravitreally injected antisense oligonucleotide, sepofarsen, was designed to modulate splicing within retinas of patients with severe vision loss due to deep intronic c.2991 + 1655A > G variant in the CEP290 gene. A previous report showed vision improvements following a single injection in one eye with unexpected durability lasting at least 15 months. The current study evaluated durability of efficacy beyond 15 months in the previously treated left eye. In addition, peak efficacy and durability were evaluated in the treatment-naive right eye, and re-injection of the left eye 4 years after the first injection. Observations Visual function was evaluated with best corrected standard and low-luminance visual acuities, microperimetry, dark-adapted chromatic perimetry, and full-field sensitivity testing. Retinal structure was evaluated with OCT imaging. At the fovea, all visual function measures and IS/OS intensity of the OCT showed transient improvements peaking at 3-6 months, remaining better than baseline at ∼2 years, and returning to baseline by 3-4 years after each single injection. Conclusions and Importance These results suggest that sepofarsen reinjection intervals may need to be longer than 2 years.
Collapse
Affiliation(s)
- Artur V. Cideciyan
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Samuel G. Jacobson
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Allen C. Ho
- Wills Eye Hospital, Thomas Jefferson University, Philadelphia, USA
| | - Malgorzata Swider
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexander Sumaroka
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alejandro J. Roman
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Vivian Wu
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert C. Russell
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Iryna Viarbitskaya
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Alexandra V. Garafalo
- Scheie Eye Institute, Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | | |
Collapse
|
7
|
Masek M, Bachmann-Gagescu R. Control of protein and lipid composition of photoreceptor outer segments-Implications for retinal disease. Curr Top Dev Biol 2023; 155:165-225. [PMID: 38043951 DOI: 10.1016/bs.ctdb.2023.09.001] [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] [Indexed: 12/05/2023]
Abstract
Vision is arguably our most important sense, and its loss brings substantial limitations to daily life for affected individuals. Light is perceived in retinal photoreceptors (PRs), which are highly specialized neurons subdivided into several compartments with distinct functions. The outer segments (OSs) of photoreceptors represent highly specialized primary ciliary compartments hosting the phototransduction cascade, which transforms incoming light into a neuronal signal. Retinal disease can result from various pathomechanisms originating in distinct subcompartments of the PR cell, or in the retinal pigment epithelium which supports the PRs. Dysfunction of primary cilia causes human disorders known as "ciliopathies", in which retinal disease is a common feature. This chapter focuses on PR OSs, discussing the mechanisms controlling their complex structure and composition. A sequence of tightly regulated sorting and trafficking events, both upstream of and within this ciliary compartment, ensures the establishment and maintenance of the adequate proteome and lipidome required for signaling in response to light. We discuss in particular our current understanding of the role of ciliopathy proteins involved in multi-protein complexes at the ciliary transition zone (CC2D2A) or BBSome (BBS1) and how their dysfunction causes retinal disease. While the loss of CC2D2A prevents the fusion of vesicles and delivery of the photopigment rhodopsin to the ciliary base, leading to early OS ultrastructural defects, BBS1 deficiency results in precocious accumulation of cholesterol in mutant OSs and decreased visual function preceding morphological changes. These distinct pathomechanisms underscore the central role of ciliary proteins involved in multiple processes controlling OS protein and lipid composition.
Collapse
Affiliation(s)
- Markus Masek
- Institute of Medical Genetics, University of Zurich, Zurich, Switzerland; Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland
| | - Ruxandra Bachmann-Gagescu
- Institute of Medical Genetics, University of Zurich, Zurich, Switzerland; Department of Molecular Life Sciences, University of Zurich, Zurich, Switzerland; University Research Priority Program AdaBD, University of Zurich, Zurich, Switzerland.
| |
Collapse
|
8
|
Corral-Serrano JC, Sladen PE, Ottaviani D, Rezek OF, Athanasiou D, Jovanovic K, van der Spuy J, Mansfield BC, Cheetham ME. Eupatilin Improves Cilia Defects in Human CEP290 Ciliopathy Models. Cells 2023; 12:1575. [PMID: 37371046 PMCID: PMC10297203 DOI: 10.3390/cells12121575] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/16/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
The photoreceptor outer segment is a highly specialized primary cilium that is essential for phototransduction and vision. Biallelic pathogenic variants in the cilia-associated gene CEP290 cause non-syndromic Leber congenital amaurosis 10 (LCA10) and syndromic diseases, where the retina is also affected. While RNA antisense oligonucleotides and gene editing are potential treatment options for the common deep intronic variant c.2991+1655A>G in CEP290, there is a need for variant-independent approaches that could be applied to a broader spectrum of ciliopathies. Here, we generated several distinct human models of CEP290-related retinal disease and investigated the effects of the flavonoid eupatilin as a potential treatment. Eupatilin improved cilium formation and length in CEP290 LCA10 patient-derived fibroblasts, in gene-edited CEP290 knockout (CEP290 KO) RPE1 cells, and in both CEP290 LCA10 and CEP290 KO iPSCs-derived retinal organoids. Furthermore, eupatilin reduced rhodopsin retention in the outer nuclear layer of CEP290 LCA10 retinal organoids. Eupatilin altered gene transcription in retinal organoids by modulating the expression of rhodopsin and by targeting cilia and synaptic plasticity pathways. This work sheds light on the mechanism of action of eupatilin and supports its potential as a variant-independent approach for CEP290-associated ciliopathies.
Collapse
Affiliation(s)
| | - Paul E. Sladen
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (P.E.S.); (D.O.)
| | - Daniele Ottaviani
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (P.E.S.); (D.O.)
- Department of Biology, University of Padova, Padova, 35122 Padova PD, Italy
| | - Olivia F. Rezek
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (P.E.S.); (D.O.)
| | - Dimitra Athanasiou
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (P.E.S.); (D.O.)
| | - Katarina Jovanovic
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (P.E.S.); (D.O.)
| | | | - Brian C. Mansfield
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, 6710B, Rockledge Drive, Montgomery County, MD 20892, USA
| | - Michael E. Cheetham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; (P.E.S.); (D.O.)
| |
Collapse
|
9
|
Grabinski SE, Parsana D, Perkins BD. Comparative analysis of transcriptional changes in zebrafish cep290 and bbs2 mutants by RNA-seq reveals upregulation of inflammatory and stress-related pathways. Front Mol Neurosci 2023; 16:1148840. [PMID: 37293546 PMCID: PMC10244513 DOI: 10.3389/fnmol.2023.1148840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 05/09/2023] [Indexed: 06/10/2023] Open
Abstract
Acute injury to the adult zebrafish retina triggers the release of pro-inflammatory cytokines and growth factors that stimulate multiple gene regulatory networks, which ultimately stimulate Müller glia to proliferate and regenerate neurons. In contrast, zebrafish carrying mutations in cep290 or bbs2 undergo progressive loss of cone photoreceptors and exhibit signs of microglia activation and inflammation, but the mutants fail to stimulate a regeneration response. To identify transcriptional changes that occur in zebrafish mutants undergoing progressive photoreceptor degeneration, RNA-seq transcriptional profiling was performed on cep290-/- and bbs2-/- retinas. The PANTHER Classification System was used to identify biological processes and signaling pathways that were differentially expressed between mutants and wild-type siblings during degeneration. As expected, genes associated with phototransduction were downregulated in cep290 and bbs2 mutants compared to wild-type siblings. Although both cep290 and bbs2 mutants undergo proliferation of rod precursors in response to retinal degeneration, the process of negatively regulating proliferation is enriched for upregulated genes, and this negative regulation may restrict proliferation of Müller glia and inhibit regeneration. A total of 815 differentially expressed genes (DEGs) were shared by cep290 and bbs2 retinas. Genes in pathways associated with inflammation, apoptosis, stress response, and PDGF signaling were overrepresented. Identifying the genes and biological pathways that are common in zebrafish models of inherited retinal degeneration provides a foundation for future studies on the mechanisms that regulate cell death as well as processes that prohibit Müller cell reprogramming or proliferation in a model capable of retinal regeneration. The pathways will provide targets for future interventions that may promote successful regeneration of lost photoreceptors.
Collapse
Affiliation(s)
- Sarah E. Grabinski
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Dhwani Parsana
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Brian D. Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, United States
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, United States
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, United States
| |
Collapse
|
10
|
Spencer WJ. Extracellular vesicles highlight many cases of photoreceptor degeneration. Front Mol Neurosci 2023; 16:1182573. [PMID: 37273908 PMCID: PMC10233141 DOI: 10.3389/fnmol.2023.1182573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 05/02/2023] [Indexed: 06/06/2023] Open
Abstract
The release of extracellular vesicles is observed across numerous cell types and serves a range of biological functions including intercellular communication and waste disposal. One cell type which stands out for its robust capacity to release extracellular vesicles is the vertebrate photoreceptor cell. For decades, the release of extracellular vesicles by photoreceptors has been documented in many different animal models of photoreceptor degeneration and, more recently, in wild type photoreceptors. Here, I review all studies describing extracellular vesicle release by photoreceptors and discuss the most unifying theme among them-a photoreceptor cell fully, or partially, diverts its light sensitive membrane material to extracellular vesicles when it has defects in the delivery or morphing of this material into the photoreceptor's highly organized light sensing organelle. Because photoreceptors generate an enormous amount of light sensitive membrane every day, the diversion of this material to extracellular vesicles can cause a massive accumulation of these membranes within the retina. Little is known about the uptake of photoreceptor derived extracellular vesicles, although in some cases the retinal pigment epithelial cells, microglia, Müller glia, and/or photoreceptor cells themselves have been shown to phagocytize them.
Collapse
|
11
|
Haggerty KN, Eshelman SC, Sexton LA, Frimpong E, Rogers LM, Agosto MA, Robichaux MA. Mapping rhodopsin trafficking in rod photoreceptors with quantitative super-resolution microscopy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.20.537413. [PMID: 37131638 PMCID: PMC10153271 DOI: 10.1101/2023.04.20.537413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Photoreceptor cells in the vertebrate retina have a highly compartmentalized morphology for efficient long-term phototransduction. Rhodopsin, the visual pigment in rod photoreceptors, is densely packaged into the rod outer segment sensory cilium and continuously renewed through essential synthesis and trafficking pathways housed in the rod inner segment. Despite the importance of this region for rod health and maintenance, the subcellular organization of rhodopsin and its trafficking regulators in the mammalian rod inner segment remain undefined. We used super-resolution fluorescence microscopy with optimized retinal immunolabeling techniques to perform a single molecule localization analysis of rhodopsin in the inner segments of mouse rods. We found that a significant fraction of rhodopsin molecules was localized at the plasma membrane in an even distribution along the entire length of the inner segment, where markers of transport vesicles also colocalized. Thus, our results collectively establish a model of rhodopsin trafficking through the inner segment plasma membrane as an essential subcellular pathway in mouse rod photoreceptors.
Collapse
Affiliation(s)
- Kristen N. Haggerty
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, 26506
| | - Shannon C. Eshelman
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, 26506
| | - Lauren A. Sexton
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, 26506
| | - Emmanuel Frimpong
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, 26506
| | - Leah M. Rogers
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, 26506
| | - Melina A. Agosto
- Retina and Optic Nerve Research Laboratory, Department of Physiology and Biophysics, and Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, NS, B3H 4R2, Canada
| | - Michael A. Robichaux
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, 26506
| |
Collapse
|
12
|
Corral-Serrano JC, Sladen PE, Ottaviani D, Rezek FO, Jovanovic K, Athanasiou D, van der Spuy J, Mansfield BC, Cheetham ME. Eupatilin improves cilia defects in human CEP290 ciliopathy models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.12.536565. [PMID: 37205323 PMCID: PMC10187159 DOI: 10.1101/2023.04.12.536565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The photoreceptor outer segment is a highly specialized primary cilium essential for phototransduction and vision. Biallelic pathogenic variants in the cilia-associated gene CEP290 cause non-syndromic Leber congenital amaurosis 10 (LCA10) and syndromic diseases, where the retina is also affected. While RNA antisense oligonucleotides and gene editing are potential treatment options for the common deep intronic variant c.2991+1655A>G in CEP290 , there is a need for variant-independent approaches that could be applied to a broader spectrum of ciliopathies. Here, we generated several distinct human models of CEP290 -related retinal disease and investigated the effects of the flavonoid eupatilin as a potential treatment. Eupatilin improved cilium formation and length in CEP290 LCA10 patient-derived fibroblasts, in gene-edited CEP290 knockout (CEP290 KO) RPE1 cells, and in both CEP290 LCA10 and CEP290 KO iPSCs-derived retinal organoids. Furthermore, eupatilin reduced rhodopsin retention in the outer nuclear layer of CEP290 LCA10 retinal organoids. Eupatilin altered gene transcription in retinal organoids, by modulating the expression of rhodopsin, and by targeting cilia and synaptic plasticity pathways. This work sheds light into the mechanism of action of eupatilin, and supports its potential as a variant-independent approach for CEP290 -associated ciliopathies. Abstract Figure
Collapse
Affiliation(s)
- JC Corral-Serrano
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - PE Sladen
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - D Ottaviani
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
- Department of Biology, University of Padova, Padova, Italy
| | - FO Rezek
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - K Jovanovic
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - D Athanasiou
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - J van der Spuy
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - BC Mansfield
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD USA
| | - ME Cheetham
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| |
Collapse
|
13
|
Weiss LE, Love JF, Yoon J, Comerci CJ, Milenkovic L, Kanie T, Jackson PK, Stearns T, Gustavsson AK. Single-molecule imaging in the primary cilium. Methods Cell Biol 2023; 176:59-83. [PMID: 37164543 PMCID: PMC10509820 DOI: 10.1016/bs.mcb.2023.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The primary cilium is an important signaling organelle critical for normal development and tissue homeostasis. Its small dimensions and complexity necessitate advanced imaging approaches to uncover the molecular mechanisms behind its function. Here, we outline how single-molecule fluorescence microscopy can be used for tracking molecular dynamics and interactions and for super-resolution imaging of nanoscale structures in the primary cilium. Specifically, we describe in detail how to capture and quantify the 2D dynamics of individual transmembrane proteins PTCH1 and SMO and how to map the 3D nanoscale distributions of the inversin compartment proteins INVS, ANKS6, and NPHP3. This protocol can, with minor modifications, be adapted for studies of other proteins and cell lines to further elucidate the structure and function of the primary cilium at the molecular level.
Collapse
Affiliation(s)
- Lucien E Weiss
- Department of Engineering Physics, Polytechnique Montréal, Montreal, QC, Canada.
| | - Julia F Love
- Department of Chemistry, Rice University, Houston, TX, United States
| | | | - Colin J Comerci
- Division of Biological Sciences, University of California San Diego, La Jolla, CA, United States
| | | | - Tomoharu Kanie
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma, OK, United States
| | - Peter K Jackson
- Baxter Laboratory, Department of Microbiology & Immunology, Stanford University School of Medicine, Stanford, CA, United States; Department of Pathology, Stanford University School of Medicine, Stanford, CA, United States
| | - Tim Stearns
- Department of Biology, Stanford University, Stanford, CA, United States; Rockefeller University, New York City, NY, United States
| | - Anna-Karin Gustavsson
- Department of Chemistry, Rice University, Houston, TX, United States; Department of BioSciences, Rice University, Houston, TX, United States; Institute of Biosciences and Bioengineering, Rice University, Houston, TX, United States; Smalley-Curl Institute, Rice University, Houston, TX, United States.
| |
Collapse
|
14
|
Tebbe L, Mwoyosvi ML, Crane R, Makia MS, Kakakhel M, Cosgrove D, Al-Ubaidi MR, Naash MI. The usherin mutation c.2299delG leads to its mislocalization and disrupts interactions with whirlin and VLGR1. Nat Commun 2023; 14:972. [PMID: 36810733 PMCID: PMC9944904 DOI: 10.1038/s41467-023-36431-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 02/01/2023] [Indexed: 02/24/2023] Open
Abstract
Usher syndrome (USH) is the leading cause of combined deafness-blindness with type 2 A (USH2A) being the most common form. Knockout models of USH proteins, like the Ush2a-/- model that develops a late-onset retinal phenotype, failed to mimic the retinal phenotype observed in patients. Since patient's mutations result in the expression of a mutant protein and to determine the mechanism of USH2A, we generated and evaluated an usherin (USH2A) knock-in mouse expressing the common human disease-mutation, c.2299delG. This mouse exhibits retinal degeneration and expresses a truncated, glycosylated protein which is mislocalized to the photoreceptor inner segment. The degeneration is associated with a decline in retinal function, structural abnormalities in connecting cilium and outer segment and mislocaliztion of the usherin interactors very long G-protein receptor 1 and whirlin. The onset of symptoms is significantly earlier compared to Ush2a-/-, proving expression of mutated protein is required to recapitulate the patients' retinal phenotype.
Collapse
Affiliation(s)
- Lars Tebbe
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA
| | - Maggie L Mwoyosvi
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA
- Department of Microbiology & Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - Ryan Crane
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA
| | - Mustafa S Makia
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA
| | - Mashal Kakakhel
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA
| | | | - Muayyad R Al-Ubaidi
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA.
| | - Muna I Naash
- Department of Biomedical Engineering, University of Houston, Houston, TX, 77204, USA.
| |
Collapse
|
15
|
Moye AR, Robichaux MA, Wensel T. Expansion Microscopy of Mouse Photoreceptor Cilia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:395-402. [PMID: 37440063 PMCID: PMC10697808 DOI: 10.1007/978-3-031-27681-1_58] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
The small size of ciliary structures that underlies photoreceptor function and inherited ciliopathies requires imaging techniques adapted to visualizing them at the highest possible resolution. In addition to powerful super-resolution imaging modalities, emerging approaches to sample preparation, including expansion microscopy (ExM), can provide a robust route to imaging specific molecules at the nanoscale level in the retina. We describe a protocol for applying ExM to whole retinas in order to achieve nanoscale fluorescence imaging of ciliary markers, including tubulin, CEP290, centrin, and CEP164. The results are consistent with those from other super-resolution fluorescence techniques and reveal new insights into their arrangements with respect to the subcompartments of photoreceptor cilia. This technique is complimentary to other imaging modalities used in retinal imaging, and can be carried out in virtually any laboratory, without the need for expensive specialized equipment.
Collapse
Affiliation(s)
- Abigail R Moye
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
- Department of Genetics and Ophthalmology, Institute of Molecular and Clinical Ophthalmology Basel, Basel, Switzerland
| | - Michael A Robichaux
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA
- Department of Ophthalmology & Visual Sciences and Department of Biochemistry & Molecular Medicine, West Virginia University, Morgantown, WV, USA
| | - Theodore Wensel
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX, USA.
| |
Collapse
|
16
|
Faber S, Roepman R. A defective structural zipper in photoreceptors causes inherited blindness. PLoS Biol 2022; 20:e3001672. [PMID: 35714125 PMCID: PMC9205488 DOI: 10.1371/journal.pbio.3001672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
This Primer explores a PLOS Biology study which uses ultrastructure expansion microscopy to study the inner scaffold of the photoreceptor connecting cilium, the location of multiple proteins implicated in inherited forms of progressive sight loss such as retinitis pigmentosa and Leber congenital amaurosis.
Collapse
Affiliation(s)
- Siebren Faber
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Ronald Roepman
- Department of Human Genetics and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
- * E-mail:
| |
Collapse
|
17
|
Mercey O, Kostic C, Bertiaux E, Giroud A, Sadian Y, Gaboriau DCA, Morrison CG, Chang N, Arsenijevic Y, Guichard P, Hamel V. The connecting cilium inner scaffold provides a structural foundation that protects against retinal degeneration. PLoS Biol 2022; 20:e3001649. [PMID: 35709082 PMCID: PMC9202906 DOI: 10.1371/journal.pbio.3001649] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 04/27/2022] [Indexed: 12/17/2022] Open
Abstract
Inherited retinal degeneration due to loss of photoreceptor cells is a leading cause of human blindness. These cells possess a photosensitive outer segment linked to the cell body through the connecting cilium (CC). While structural defects of the CC have been associated with retinal degeneration, its nanoscale molecular composition, assembly, and function are barely known. Here, using expansion microscopy and electron microscopy, we reveal the molecular architecture of the CC and demonstrate that microtubules are linked together by a CC inner scaffold containing POC5, CENTRIN, and FAM161A. Dissecting CC inner scaffold assembly during photoreceptor development in mouse revealed that it acts as a structural zipper, progressively bridging microtubule doublets and straightening the CC. Furthermore, we show that Fam161a disruption in mouse leads to specific CC inner scaffold loss and triggers microtubule doublet spreading, prior to outer segment collapse and photoreceptor degeneration, suggesting a molecular mechanism for a subtype of retinitis pigmentosa. Inherited retinal degeneration due to loss of photoreceptor cells is a leading cause of human blindness. Ultrastructure expansion microscopy on mouse retina reveals the presence of a novel structure inside the photoreceptor connecting cilium, the inner scaffold, that protects the outer segment against degeneration.
Collapse
Affiliation(s)
- Olivier Mercey
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Corinne Kostic
- Group for Retinal Disorder Research, Department of Ophthalmology, University Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - Eloïse Bertiaux
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Alexia Giroud
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Yashar Sadian
- CryoGenic Facility, University of Geneva, Geneva, Switzerland
| | - David C. A. Gaboriau
- Centre for Chromosome Biology, National University of Ireland Galway, Galway, Ireland
| | - Ciaran G. Morrison
- Centre for Chromosome Biology, National University of Ireland Galway, Galway, Ireland
| | - Ning Chang
- Unit of Retinal Degeneration and Regeneration, Department of Ophthalmology, University Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - Yvan Arsenijevic
- Unit of Retinal Degeneration and Regeneration, Department of Ophthalmology, University Lausanne, Jules-Gonin Eye Hospital, Fondation Asile des Aveugles, Lausanne, Switzerland
| | - Paul Guichard
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
- * E-mail: (PG); (VH)
| | - Virginie Hamel
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
- * E-mail: (PG); (VH)
| |
Collapse
|
18
|
Chahine Karam F, Loi TH, Ma A, Nash BM, Grigg JR, Parekh D, Riley LG, Farnsworth E, Bennetts B, Gonzalez-Cordero A, Jamieson RV. Human iPSC-Derived Retinal Organoids and Retinal Pigment Epithelium for Novel Intronic RPGR Variant Assessment for Therapy Suitability. J Pers Med 2022; 12:jpm12030502. [PMID: 35330501 PMCID: PMC8951517 DOI: 10.3390/jpm12030502] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 02/04/2023] Open
Abstract
The RPGR gene encodes Retinitis Pigmentosa GTPase Regulator, a known interactor with ciliary proteins, which is involved in maintaining healthy photoreceptor cells. Variants in RPGR are the main contributor to X-linked rod-cone dystrophy (RCD), and RPGR gene therapy approaches are in clinical trials. Hence, elucidation of the pathogenicity of novel RPGR variants is important for a patient therapy opportunity. Here, we describe a novel intronic RPGR variant, c.1415 − 9A>G, in a patient with RCD, which was classified as a variant of uncertain significance according to current clinical diagnostic criteria. The variant lay several base pairs intronic to the canonical splice acceptor site, raising suspicion of an RPGR RNA splicing abnormality and consequent protein dysfunction. To investigate disease causation in an appropriate disease model, induced pluripotent stem cells were generated from patient fibroblasts and differentiated to retinal pigment epithelium (iPSC-RPE) and retinal organoids (iPSC-RO). Abnormal RNA splicing of RPGR was demonstrated in patient fibroblasts, iPSC-RPE and iPSC-ROs, leading to a predicted frameshift and premature stop codon. Decreased RPGR expression was demonstrated in these cell types, with a striking loss of RPGR localization at the ciliary transitional zone, critically in the photoreceptor cilium of the patient iPSC-ROs. Mislocalisation of rhodopsin staining was present in the patient’s iPSC-RO rod photoreceptor cells, along with an abnormality of L/M opsin staining affecting cone photoreceptor cells and increased photoreceptor apoptosis. Additionally, patient iPSC-ROs displayed an increase in F-actin expression that was consistent with an abnormal actin regulation phenotype. Collectively, these studies indicate that the splicing abnormality caused by the c.1415 − 9A>G variant has an impact on RPGR function. This work has enabled the reclassification of this variant to pathogenic, allowing the consideration of patients with this variant having access to gene therapy clinical trials. In addition, we have identified biomarkers of disease suitable for the interrogation of other RPGR variants of uncertain significance.
Collapse
Affiliation(s)
- Fidelle Chahine Karam
- Eye Genetics Research Unit, Children’s Medical Research Institute, Sydney Children’s Hospitals Network, Save Sight Institute, University of Sydney, Westmead, Sydney 2145, Australia; (F.C.K.); (T.H.L.); (A.M.); (B.M.N.); (J.R.G.)
| | - To Ha Loi
- Eye Genetics Research Unit, Children’s Medical Research Institute, Sydney Children’s Hospitals Network, Save Sight Institute, University of Sydney, Westmead, Sydney 2145, Australia; (F.C.K.); (T.H.L.); (A.M.); (B.M.N.); (J.R.G.)
| | - Alan Ma
- Eye Genetics Research Unit, Children’s Medical Research Institute, Sydney Children’s Hospitals Network, Save Sight Institute, University of Sydney, Westmead, Sydney 2145, Australia; (F.C.K.); (T.H.L.); (A.M.); (B.M.N.); (J.R.G.)
- Department of Clinical Genetics, Western Sydney Genetics Program, Sydney Children’s Hospitals Network, Westmead, Sydney 2145, Australia
- Specialty of Genomic Medicine, Faculty of Medicine and Health, University of Sydney, Westmead, Sydney 2145, Australia; (E.F.); (B.B.)
| | - Benjamin M. Nash
- Eye Genetics Research Unit, Children’s Medical Research Institute, Sydney Children’s Hospitals Network, Save Sight Institute, University of Sydney, Westmead, Sydney 2145, Australia; (F.C.K.); (T.H.L.); (A.M.); (B.M.N.); (J.R.G.)
- Specialty of Genomic Medicine, Faculty of Medicine and Health, University of Sydney, Westmead, Sydney 2145, Australia; (E.F.); (B.B.)
- Sydney Genome Diagnostics, Western Sydney Genetics Program, Sydney Children’s Hospitals Network, Westmead, Sydney 2145, Australia
| | - John R. Grigg
- Eye Genetics Research Unit, Children’s Medical Research Institute, Sydney Children’s Hospitals Network, Save Sight Institute, University of Sydney, Westmead, Sydney 2145, Australia; (F.C.K.); (T.H.L.); (A.M.); (B.M.N.); (J.R.G.)
- Specialty of Ophthalmology, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia
| | - Darshan Parekh
- Rare Diseases Functional Genomics Laboratory, Sydney Children’s Hospitals Network and Children’s Medical Research Institute, Westmead, Sydney 2145, Australia; (D.P.); (L.G.R.)
| | - Lisa G. Riley
- Rare Diseases Functional Genomics Laboratory, Sydney Children’s Hospitals Network and Children’s Medical Research Institute, Westmead, Sydney 2145, Australia; (D.P.); (L.G.R.)
- Specialty of Child and Adolescent Health, University of Sydney, Westmead, Sydney 2145, Australia
| | - Elizabeth Farnsworth
- Specialty of Genomic Medicine, Faculty of Medicine and Health, University of Sydney, Westmead, Sydney 2145, Australia; (E.F.); (B.B.)
- Sydney Genome Diagnostics, Western Sydney Genetics Program, Sydney Children’s Hospitals Network, Westmead, Sydney 2145, Australia
| | - Bruce Bennetts
- Specialty of Genomic Medicine, Faculty of Medicine and Health, University of Sydney, Westmead, Sydney 2145, Australia; (E.F.); (B.B.)
- Sydney Genome Diagnostics, Western Sydney Genetics Program, Sydney Children’s Hospitals Network, Westmead, Sydney 2145, Australia
| | - Anai Gonzalez-Cordero
- Stem Cell Medicine Group, Children’s Medical Research Institute, University of Sydney, Westmead, Sydney 2145, Australia;
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia
| | - Robyn V. Jamieson
- Eye Genetics Research Unit, Children’s Medical Research Institute, Sydney Children’s Hospitals Network, Save Sight Institute, University of Sydney, Westmead, Sydney 2145, Australia; (F.C.K.); (T.H.L.); (A.M.); (B.M.N.); (J.R.G.)
- Department of Clinical Genetics, Western Sydney Genetics Program, Sydney Children’s Hospitals Network, Westmead, Sydney 2145, Australia
- Specialty of Genomic Medicine, Faculty of Medicine and Health, University of Sydney, Westmead, Sydney 2145, Australia; (E.F.); (B.B.)
- Correspondence: ; Tel.: +61-2-9687-2800; Fax: +61-2-9687-2120
| |
Collapse
|