1
|
Weller M, Müller B, Stieger K. Long-Term Porcine Retina Explants as an Alternative to In Vivo Experimentation. Transl Vis Sci Technol 2024; 13:9. [PMID: 38477924 PMCID: PMC10941994 DOI: 10.1167/tvst.13.3.9] [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: 05/26/2023] [Accepted: 01/24/2024] [Indexed: 03/14/2024] Open
Abstract
Purpose The porcine retina represents an optimal model system to study treatment approaches for inherited retinal dystrophies owing to close anatomical similarities to the human retina, including a cone enriched visual streak. The aim of this work was to establish a protocol to keep explants in culture for up to 28 days with good morphological preservation. Methods Two to four retina explants per eye were obtained from the central part of the retina and transferred onto a membrane insert with the photoreceptors facing down. Different medium compositions using Neurobasal-A medium containing 100 or 450 mg/dL glucose and combinations of fetal calf serum, B-27 with or without insulin and N-2 were tested. We developed a tissue quality score with robust markers for different retinal cell types (protein kinase C alpha, peanut agglutinin and 4',6-diamidino-2-phenylindol). Results Retinae were kept until 28 days with only little degradation. The best results were attained using Neurobasal-A medium containing 100 mg/dL glucose supplemented with B-27 containing insulin and N-2. For an easy preparation process, it is necessary to minimize transport time and keep the eyes on ice until dissected. Heat-mediated decontamination by the butcher has to be avoided. Conclusions Using a standardized protocol, porcine retina explants represent an easy to handle intermediate model between in vitro and in vivo experimentation. This model system is robustly reproducible and contributes to the implementation of the 3R principle to minimize animal experimentation. Translational Relevance This model can be used to test future therapeutic approaches for inherited retinal dystrophies.
Collapse
Affiliation(s)
- Maria Weller
- Department of Ophthalmology, Justus-Liebig-University Giessen, Germany
| | - Brigitte Müller
- Department of Ophthalmology, Justus-Liebig-University Giessen, Germany
| | - Knut Stieger
- Department of Ophthalmology, Justus-Liebig-University Giessen, Germany
| |
Collapse
|
2
|
Lu K, Liang XF, Tang SL, Wu J, Zhang L, Wang Y, Chai F. Role of short-wave-sensitive 1 (sws1) in cone development and first feeding in larval zebrafish. FISH PHYSIOLOGY AND BIOCHEMISTRY 2023; 49:801-813. [PMID: 37495865 DOI: 10.1007/s10695-023-01213-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 06/22/2023] [Indexed: 07/28/2023]
Abstract
Color vision is mediated by the expression of different major visual pigment proteins (opsins) on retinal photoreceptors. Vertebrates have four classes of cone opsins that are most sensitive to different wavelengths of light: short wavelength sensitive 1 (SWS1), short wavelength sensitive 2 (SWS2), medium wavelength sensitive (RH2), and long wavelength sensitive (LWS). UV wavelengths play important roles in foraging and communication. However, direct evidence provide links between sws1 and first feeding is lacking. Here, CRISPR/Cas9 technology was performed to generate mutant zebrafish lines with sws1 deletion. sws1 mutant zebrafish larvae exhibited decreased sws1, rh2-2, and lws1 expression, and increased rod gene (rho and gnat1) expression. Furthermore, the sws1-deficient larvae exhibited significantly reduced food intake, and the orexigenic genes npy and agrp signaling were upregulated at 6 days postfertilization (dpf). The transcription expression of sws1 and rh2-3 genes decreased in sws1-/- adults compared to wild type. Surprisingly, the results of feeding at the adult stage were not the same with larvae. sws1 deficiency did not affect food intake and appetite gene expression at adult stages. These results reveal a role for sws1 in normal cone development and first feeding in larval zebrafish.
Collapse
Affiliation(s)
- Ke Lu
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Xu-Fang Liang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China.
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China.
| | - Shu-Lin Tang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Jiaqi Wu
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Lixin Zhang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Yuye Wang
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| | - Farui Chai
- College of Fisheries, Chinese Perch Research Center, Huazhong Agricultural University, Wuhan, 430070, China
- Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt, Ministry of Education, Wuhan, 430070, China
| |
Collapse
|
3
|
Castellini ME, Spagnolli G, Poggi L, Biasini E, Casarosa S, Messina A. Identification of the zebrafish homologues of IMPG2, a retinal proteoglycan. Cell Tissue Res 2023; 394:93-105. [PMID: 37470839 PMCID: PMC10558372 DOI: 10.1007/s00441-023-03808-z] [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: 03/06/2023] [Accepted: 07/05/2023] [Indexed: 07/21/2023]
Abstract
Photoreceptor outer segments are surrounded by a carbohydrate-rich matrix, the interphotoreceptor matrix, necessary for physiological retinal function. Few roles for molecules characterizing the interphotoreceptor matrix have been clearly defined. Recent studies have found the presence of nonsense mutations in the interphotoreceptor matrix proteoglycan 2 (IMPG2) gene in patients affected by retinal dystrophies. IMPG2 encodes for a proteoglycan synthesized by photoreceptors and secreted in the interphotoreceptor matrix. Little is known about the structure and function of this protein, we thus decided to characterize zebrafish impg2. In zebrafish there are two Impg2 proteins, Impg2a and Impg2b. We generated a phylogenetic tree based on IMPG2 protein sequence similarity among vertebrates, showing a significant similarity between humans and teleosts. The human and zebrafish proteins share conserved domains, as also shown by homology models. Expression analyses of impg2a and impg2b show a continued expression in the photoreceptor layer starting from developmental stages and continuing through adulthood. Between 1 and 6 months post-fertilization, there is a significant shift of Impg2 expression toward the outer segment region, suggesting an increase in secretion. This raises intriguing hypotheses about its possible role(s) during retinal maturation, laying the groundwork for the generation of most needed models for the study of IMPG2-related inherited retinal dystrophies.
Collapse
Affiliation(s)
- M E Castellini
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive, 9, 38123, Povo, TN, Italy
| | - G Spagnolli
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive, 9, 38123, Povo, TN, Italy
- Sibylla Biotech S.R.L, Piazzetta Chiavica 2 - 37121, Verona, VR, Italy
| | - L Poggi
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive, 9, 38123, Povo, TN, Italy
- Centre for Medical Sciences (CISMed), University of Trento, Via S. Maria Maddalena, 1, 38122, Trento, TN, Italy
| | - E Biasini
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive, 9, 38123, Povo, TN, Italy
- Centre for Medical Sciences (CISMed), University of Trento, Via S. Maria Maddalena, 1, 38122, Trento, TN, Italy
| | - S Casarosa
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive, 9, 38123, Povo, TN, Italy.
- Centre for Medical Sciences (CISMed), University of Trento, Via S. Maria Maddalena, 1, 38122, Trento, TN, Italy.
| | - A Messina
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Via Sommarive, 9, 38123, Povo, TN, Italy
- Centre for Mind/Brain Sciences (CIMeC), University of Trento, Piazza Manifattura 1, 38068, Rovereto, TN, Italy
| |
Collapse
|
4
|
Krylov A, Yu S, Veen K, Newton A, Ye A, Qin H, He J, Jusuf PR. Heterogeneity in quiescent Müller glia in the uninjured zebrafish retina drive differential responses following photoreceptor ablation. Front Mol Neurosci 2023; 16:1087136. [PMID: 37575968 PMCID: PMC10413128 DOI: 10.3389/fnmol.2023.1087136] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 06/23/2023] [Indexed: 08/15/2023] Open
Abstract
Introduction Loss of neurons in the neural retina is a leading cause of vision loss. While humans do not possess the capacity for retinal regeneration, zebrafish can achieve this through activation of resident Müller glia. Remarkably, despite the presence of Müller glia in humans and other mammalian vertebrates, these cells lack an intrinsic ability to contribute to regeneration. Upon activation, zebrafish Müller glia can adopt a stem cell-like state, undergo proliferation and generate new neurons. However, the underlying molecular mechanisms of this activation subsequent retinal regeneration remains unclear. Methods/Results To address this, we performed single-cell RNA sequencing (scRNA-seq) and report remarkable heterogeneity in gene expression within quiescent Müller glia across distinct dorsal, central and ventral retina pools of such cells. Next, we utilized a genetically driven, chemically inducible nitroreductase approach to study Müller glia activation following selective ablation of three distinct photoreceptor subtypes: long wavelength sensitive cones, short wavelength sensitive cones, and rods. There, our data revealed that a region-specific bias in activation of Müller glia exists in the zebrafish retina, and this is independent of the distribution of the ablated cell type across retinal regions. Notably, gene ontology analysis revealed that injury-responsive dorsal and central Müller glia express genes related to dorsal/ventral pattern formation, growth factor activity, and regulation of developmental process. Through scRNA-seq analysis, we identify a shared genetic program underlying initial Müller glia activation and cell cycle entry, followed by differences that drive the fate of regenerating neurons. We observed an initial expression of AP-1 and injury-responsive transcription factors, followed by genes involved in Notch signaling, ribosome biogenesis and gliogenesis, and finally expression of cell cycle, chromatin remodeling and microtubule-associated genes. Discussion Taken together, our findings document the regional specificity of gene expression within quiescent Müller glia and demonstrate unique Müller glia activation and regeneration features following neural ablation. These findings will improve our understanding of the molecular pathways relevant to neural regeneration in the retina.
Collapse
Affiliation(s)
- Aaron Krylov
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Shuguang Yu
- State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Kellie Veen
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Axel Newton
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| | - Aojun Ye
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Huiwen Qin
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Jie He
- State Key Laboratory of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Institute of Neuroscience, Chinese Academy of Sciences, Shanghai, China
| | - Patricia R. Jusuf
- School of BioSciences, University of Melbourne, Parkville, VIC, Australia
| |
Collapse
|
5
|
Schellens RT, Broekman S, Peters T, Graave P, Malinar L, Venselaar H, Kremer H, De Vrieze E, Van Wijk E. A protein domain-oriented approach to expand the opportunities of therapeutic exon skipping for USH2A-associated retinitis pigmentosa. MOLECULAR THERAPY. NUCLEIC ACIDS 2023; 32:980-994. [PMID: 37313440 PMCID: PMC10258241 DOI: 10.1016/j.omtn.2023.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 05/17/2023] [Indexed: 06/15/2023]
Abstract
Loss-of-function mutations in USH2A are among the most common causes of syndromic and non-syndromic retinitis pigmentosa (RP). We previously presented skipping of USH2A exon 13 as a promising treatment paradigm for USH2A-associated RP. However, RP-associated mutations are often private, and evenly distributed along the USH2A gene. In order to broaden the group of patients that could benefit from therapeutic exon skipping strategies, we expanded our approach to other USH2A exons in which unique loss-of-function mutations have been reported by implementing a protein domain-oriented dual exon skipping strategy. We first generated zebrafish mutants carrying a genomic deletion of the orthologous exons of the frequently mutated human USH2A exons 30-31 or 39-40 using CRISPR-Cas9. Excision of these in-frame combinations of exons restored usherin expression in the zebrafish retina and rescued the photopigment mislocalization typically observed in ush2a mutants. To translate these findings into a future treatment in humans, we employed in vitro assays to identify and validate antisense oligonucleotides (ASOs) with a high potency for sequence-specific dual exon skipping. Together, the in vitro and in vivo data demonstrate protein domain-oriented ASO-induced dual exon skipping to be a highly promising treatment option for RP caused by mutations in USH2A.
Collapse
Affiliation(s)
- Renske T.W. Schellens
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, 6525GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, 6500 GL Nijmegen, the Netherlands
| | - Sanne Broekman
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, 6525GA Nijmegen, the Netherlands
| | - Theo Peters
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, 6525GA Nijmegen, the Netherlands
| | - Pam Graave
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Lucija Malinar
- Center for Molecular and Biomolecular Informatics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Hanka Venselaar
- Center for Molecular and Biomolecular Informatics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Hannie Kremer
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, 6525GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, 6500 GL Nijmegen, the Netherlands
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, the Netherlands
| | - Erik De Vrieze
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, 6525GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, 6500 GL Nijmegen, the Netherlands
| | - Erwin Van Wijk
- Department of Otorhinolaryngology, Hearing and Genes, Radboud University Medical Center, 6525GA Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, 6500 GL Nijmegen, the Netherlands
| |
Collapse
|
6
|
Stemerdink M, Broekman S, Peters T, Kremer H, de Vrieze E, van Wijk E. Generation and Characterization of a Zebrafish Model for ADGRV1-Associated Retinal Dysfunction Using CRISPR/Cas9 Genome Editing Technology. Cells 2023; 12:1598. [PMID: 37371069 DOI: 10.3390/cells12121598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/26/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023] Open
Abstract
Worldwide, around 40,000 people progressively lose their eyesight as a consequence of retinitis pigmentosa (RP) caused by pathogenic variants in the ADGRV1 gene, for which currently no treatment options exist. A model organism that mimics the human phenotype is essential to unravel the exact pathophysiological mechanism underlying ADGRV1-associated RP, and to evaluate future therapeutic strategies. The introduction of CRISPR/Cas-based genome editing technologies significantly improved the possibilities of generating mutant models in a time- and cost-effective manner. Zebrafish have been recognized as a suitable model to study Usher syndrome-associated retinal dysfunction. Using CRISPR/Cas9 technology we introduced a 4bp deletion in adgrv1 exon 9 (adgrv1rmc22). Immunohistochemical analysis showed that Adgrv1 was absent from the region of the photoreceptor connecting cilium in the adgrv1rmc22 zebrafish retina. Here, the absence of Adgrv1 also resulted in reduced levels of the USH2 complex members usherin and Whrnb, suggesting that Adgrv1 interacts with usherin and Whrnb in zebrafish photoreceptors. When comparing adgrv1rmc22 zebrafish with wild-type controls, we furthermore observed increased levels of aberrantly localized rhodopsin in the photoreceptor cell body, and decreased electroretinogram (ERG) B-wave amplitudes which indicate that the absence of Adgrv1 results in impaired retinal function. Based on these findings we present the adgrv1rmc22 zebrafish as the first ADGRV1 mutant model that displays an early retinal dysfunction. Moreover, the observed phenotypic changes can be used as quantifiable outcome measures when evaluating the efficacy of future novel therapeutic strategies for ADGRV1-associated RP.
Collapse
Affiliation(s)
- Merel Stemerdink
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Sanne Broekman
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Theo Peters
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Hannie Kremer
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Department of Human Genetics, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Erik de Vrieze
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Erwin van Wijk
- Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| |
Collapse
|
7
|
Abu Bakar N, Wan Ibrahim WN, Zulkiflli AR, Saleh Hodin NA, Kim TY, Ling YS, Md Ajat MM, Shaari K, Shohaimi S, Nasruddin NS, Mohd Faudzi SM, Kim CH. Embryonic mercury exposure in zebrafish: Alteration of metabolites and gene expression, related to visual and behavioral impairments. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 256:114862. [PMID: 37004432 DOI: 10.1016/j.ecoenv.2023.114862] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 03/05/2023] [Accepted: 03/30/2023] [Indexed: 06/19/2023]
Abstract
The widespread presence of mercury, a heavy metal found in the environment and used in numerous industries and domestic, raises concerns about its potential impact on human health. Nevertheless, the adverse effects of this environmental toxicant at low concentrations are often underestimated. There are emerging studies showing that accumulation of mercury in the eye may contribute to visual impairment and a comorbidity between autism spectrum disorders (ASD) trait and visual impairment. However, the underlying mechanism of visual impairment in humans and rodents is challenging. In response to this issue, zebrafish larvae with a cone-dominated retinal visual system were exposed to 100 nM mercury chloride (HgCl2), according to our previous study, followed by light-dark stimulation, a social assay, and color preference to examine the functionality of the visual system in relation to ASD-like behavior. Exposure of embryos to HgCl2 from gastrulation to hatching increased locomotor activity in the dark, reduced shoaling and exploratory behavior, and impaired color preference. Defects in microridges as the first barrier may serve as primary tools for HgCl2 toxicity affecting vision. Depletion of polyunsaturated fatty acids (PUFAs), linoleic acid, arachidonic acid (ARA), alpha-linoleic acid, docosahexaenoic acid (DHA), stearic acid, L-phenylalanine, isoleucine, L-lysine, and N-acetylputrescine, along with the increase of gamma-aminobutyric acid (GABA), sphingosine-1-phosphate, and citrulline assayed by liquid chromatography-mass spectrometry (LC-MS) suggest that these metabolites serve as biomarkers of retinal impairments that affect vision and behavior. Although suppression of adsl, shank3a, tsc1b, and nrxn1a gene expression was observed, among these tsc1b showed more positive correlation with ASD. Collectively, these results contribute new insights into the possible mechanism of mercury toxicity give rise to visual, cognitive, and social deficits in zebrafish.
Collapse
Affiliation(s)
- Noraini Abu Bakar
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Wan Norhamidah Wan Ibrahim
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Natural Medicines and Product Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Abdul Rahman Zulkiflli
- Natural Medicines and Product Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Nur Atikah Saleh Hodin
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Tae-Yoon Kim
- Department of Biology, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Yee Soon Ling
- Biotechnology Research Institute, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah, Malaysia
| | - Mohd Mokrish Md Ajat
- Natural Medicines and Product Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Veterinary Preclinical Sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400, Malaysia
| | - Khozirah Shaari
- Natural Medicines and Product Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Shamarina Shohaimi
- Department of Biology, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
| | - Nurrul Shaqinah Nasruddin
- Centre for Craniofacial Diagnostics, Faculty of Dentistry, Universiti Kebangsaan Malaysia (UKM), 50300 Kuala Lumpur, Malaysia
| | - Siti Munirah Mohd Faudzi
- Natural Medicines and Product Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
| | - Cheol-Hee Kim
- Department of Biology, Chungnam National University, Daejeon 34134, Republic of Korea.
| |
Collapse
|
8
|
Berger S, D. Currie P, Berger J. The Role of TRiC-enhanced Actin Folding in Leber Congenital Amaurosis. J Ophthalmic Vis Res 2023; 18:60-67. [PMID: 36937198 PMCID: PMC10020782 DOI: 10.18502/jovr.v18i1.12726] [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: 05/14/2022] [Accepted: 11/05/2022] [Indexed: 02/24/2023] Open
Abstract
Purpose Mutations in TCP-1 ring complex (TRiC) have been associated with Leber Congenital Amaurosis (LCA). TRiC is involved in protein folding and has 8 essential subunits including CCT5. Herein, we studied the retina of TRiC mutant zebrafish to evaluate the possible role of impaired actin and tubulin folding in LCA. Methods The cct5 t f 212 b retina was histologically studied using Toluidine Blue staining as well as TUNEL, BrdU-labeling, and Phalloidin assays. Retinal organisation was assessed by quantification of the cellularity utilising DAPI. Results Laminar organization of cct5 t f 212 b retinas was intact. Enhanced apoptosis throughout the cct5 t f 212 b retina was not compensated by higher proliferation rates, leaving the cct5 t f 212 b retina smaller in size. Quantification of retinal layer cellularity demonstrated that specifically the numbers of the amacrine and the retinal ganglion cells were depleted, suggesting that the cct5 t f 212 b retina was not uniformly affected by the reduced actin folding. Conclusion Whereas the current literature suggests that LCA is predominantly affecting retinal photoreceptor cells and the retinal pigment epithelium, cct5 t f 212 b analyses demonstrated the important role of folding of actin by TRiC, suggesting that cct5 t f 212 b is a useful tool to specifically analyze the role of F-actin filaments in the context of LCA.
Collapse
Affiliation(s)
- Silke Berger
- Australian Regenerative Medicine Institute, Monash University, Clayton, Australia
- Victoria Node, EMBL Australia, Clayton, Australia
| | - Peter D. Currie
- Australian Regenerative Medicine Institute, Monash University, Clayton, Australia
- Victoria Node, EMBL Australia, Clayton, Australia
| | - Joachim Berger
- Australian Regenerative Medicine Institute, Monash University, Clayton, Australia
- Victoria Node, EMBL Australia, Clayton, Australia
| |
Collapse
|
9
|
Bise T, Pfefferli C, Bonvin M, Taylor L, Lischer HEL, Bruggmann R, Jaźwińska A. The regeneration-responsive element careg monitors activation of Müller glia after MNU-induced damage of photoreceptors in the zebrafish retina. Front Mol Neurosci 2023; 16:1160707. [PMID: 37138703 PMCID: PMC10149768 DOI: 10.3389/fnmol.2023.1160707] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/27/2023] [Indexed: 05/05/2023] Open
Abstract
In contrast to mammals, zebrafish can regenerate their damaged photoreceptors. This capacity depends on the intrinsic plasticity of Müller glia (MG). Here, we identified that the transgenic reporter careg, a marker of regenerating fin and heart, also participates in retina restoration in zebrafish. After methylnitrosourea (MNU) treatment, the retina became deteriorated and contained damaged cell types including rods, UV-sensitive cones and the outer plexiform layer. This phenotype was associated with the induction of careg expression in a subset of MG until the reconstruction of the photoreceptor synaptic layer. Single-cell RNA sequencing (scRNAseq) analysis of regenerating retinas revealed a population of immature rods, defined by high expression of rhodopsin and the ciliogenesis gene meig1, but low expression of phototransduction genes. Furthermore, cones displayed deregulation of metabolic and visual perception genes in response to retina injury. Comparison between careg:EGFP expressing and non-expressing MG demonstrated that these two subpopulations are characterized by distinct molecular signatures, suggesting their heterogenous responsiveness to the regenerative program. Dynamics of ribosomal protein S6 phosphorylation showed that TOR signaling became progressively switched from MG to progenitors. Inhibition of TOR with rapamycin reduced the cell cycle activity, but neither affected careg:EGFP expression in MG, nor prevented restoration of the retina structure. This indicates that MG reprogramming, and progenitor cell proliferation might be regulated by distinct mechanisms. In conclusion, the careg reporter detects activated MG, and provides a common marker of regeneration-competent cells in diverse zebrafish organs, including the retina.
Collapse
Affiliation(s)
- Thomas Bise
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | | | - Marylène Bonvin
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Lea Taylor
- Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Heidi E. L. Lischer
- Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Rémy Bruggmann
- Interfaculty Bioinformatics Unit, University of Bern, Bern, Switzerland
- Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland
| | - Anna Jaźwińska
- Department of Biology, University of Fribourg, Fribourg, Switzerland
- *Correspondence: Anna Jaźwińska,
| |
Collapse
|
10
|
Abdolkarimi D, Cunha DL, Lahne1 M, Moosajee M. PAX6 disease models for aniridia. Indian J Ophthalmol 2022; 70:4119-4129. [PMID: 36453299 PMCID: PMC9940591 DOI: 10.4103/ijo.ijo_316_22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/01/2022] [Accepted: 08/10/2022] [Indexed: 12/12/2022] Open
Abstract
Aniridia is a pan-ocular genetic developmental eye disorder characterized by complete or partial iris and foveal hypoplasia, for which there is no treatment currently. Progressive sight loss can arise from cataracts, glaucoma, and aniridia-related keratopathy, which can be managed conservatively or through surgical intervention. The vast majority of patients harbor heterozygous mutations involving the PAX6 gene, which is considered the master transcription factor of early eye development. Over the past decades, several disease models have been investigated to gain a better understanding of the molecular pathophysiology, including several mouse and zebrafish strains and, more recently, human-induced pluripotent stem cells (hiPSCs) derived from aniridia patients. The latter provides a more faithful cellular system to study early human eye development. This review outlines the main aniridia-related animal and cellular models used to study aniridia and highlights the key discoveries that are bringing us closer to a therapy for patients.
Collapse
Affiliation(s)
| | - Dulce Lima Cunha
- UCL Institute of Ophthalmology, London, UK
- Radboud Institute for Molecular Life Sciences, Radboud University, Nijmegen, Netherlands
| | | | - Mariya Moosajee
- UCL Institute of Ophthalmology, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
- The Francis Crick Institute, London, UK
| |
Collapse
|
11
|
Fliesler SJ, Ramachandra Rao S, Nguyen MN, KhalafAllah MT, Pittler SJ. Vertebrate Animal Models of RP59: Current Status and Future Prospects. Int J Mol Sci 2022; 23:13324. [PMID: 36362109 PMCID: PMC9657489 DOI: 10.3390/ijms232113324] [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: 09/14/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 09/20/2023] Open
Abstract
Retinitis pigmentosa-59 (RP59) is a rare, recessive form of RP, caused by mutations in the gene encoding DHDDS (dehydrodolichyl diphosphate synthase). DHDDS forms a heterotetrameric complex with Nogo-B receptor (NgBR; gene NUS1) to form a cis-prenyltransferase (CPT) enzyme complex, which is required for the synthesis of dolichol, which in turn is required for protein N-glycosylation as well as other glycosylation reactions in eukaryotic cells. Herein, we review the published phenotypic characteristics of RP59 models extant, with an emphasis on their ocular phenotypes, based primarily upon knock-in of known RP59-associated DHDDS mutations as well as cell type- and tissue-specific knockout of DHDDS alleles in mice. We also briefly review findings in RP59 patients with retinal disease and other patients with DHDDS mutations causing epilepsy and other neurologic disease. We discuss these findings in the context of addressing "knowledge gaps" in our current understanding of the underlying pathobiology mechanism of RP59, as well as their potential utility for developing therapeutic interventions to block the onset or to dampen the severity or progression of RP59.
Collapse
Affiliation(s)
- Steven J. Fliesler
- Departments of Ophthalmology and Biochemistry, Neuroscience Graduate Program, Jacobs School of Medicine, State University of New York—University at Buffalo, Buffalo, NY 14203, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY 14215, USA
| | - Sriganesh Ramachandra Rao
- Departments of Ophthalmology and Biochemistry, Neuroscience Graduate Program, Jacobs School of Medicine, State University of New York—University at Buffalo, Buffalo, NY 14203, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY 14215, USA
| | - Mai N. Nguyen
- Department of Optometry and Vision Science, Vision Science Research Center, School of Optometry, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Mahmoud Tawfik KhalafAllah
- Department of Optometry and Vision Science, Vision Science Research Center, School of Optometry, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Steven J. Pittler
- Department of Optometry and Vision Science, Vision Science Research Center, School of Optometry, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| |
Collapse
|
12
|
Liu S, Chen T, Chen B, Liu Y, Lu X, Li J. Lrpap1 deficiency leads to myopia through TGF-β-induced apoptosis in zebrafish. Cell Commun Signal 2022; 20:162. [PMID: 36261846 PMCID: PMC9580148 DOI: 10.1186/s12964-022-00970-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 09/03/2022] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Frameshift mutations in LRPAP1 are responsible for autosomal recessive high myopia in human beings but its underlying mechanism remains elusive. This study aims to investigate the effect of LRPAP1 defect on ocular refractive development and its involved mechanism. METHODS A lrpap1 mutant zebrafish line with homozygous frameshift mutation was generated by CRISPR/Cas9 technology and confirmed by Sanger sequencing. The ocular refractive phenotype was analyzed by calculating the relative refractive error (RRE) with vivo photography and histological analysis at different development stages, together with examining ocular structure change via transmission electron microscopy. Further, RNA sequencing and bioinformatics analysis were performed. The potentially involved signaling pathway as well as the interacted protein were investigated in vivo. RESULTS The lrpap1 homozygous mutant zebrafish line showed myopic phenotype. Specifically, the mutant lines showed larger eye axial length-to-body length in one-month old individuals and a myopic shift with an RRE that changed after two months. Collagen fibers became thinning and disordered in the sclera. Further, RNA sequencing and bioinformatics analysis indicated that apoptosis signaling was activated in mutant line; this was further confirmed by acridine orange and TUNEL staining. Moreover, the expression of TGF-β protein was elevated in the mutant lines. Finally, the treatment of wild-type embryos with a TGF-β agonist aggravated the degree of eyeball apoptosis; conversely, the use of a TGF-β inhibitor mitigated apoptosis in mutant embryos. CONCLUSION The study provides functional evidence of a link between lrpap1 and myopia, suggesting that lrpap1 deficiency could lead to myopia through TGF-β-induced apoptosis signaling. Video abstract.
Collapse
Affiliation(s)
- Shanshan Liu
- grid.284723.80000 0000 8877 7471Department of Ophthalmology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Ting Chen
- grid.284723.80000 0000 8877 7471Department of Ophthalmology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Binghao Chen
- grid.459579.30000 0004 0625 057XDepartment of Orthopedics, Guangdong Women and Children Hospital, Guangzhou, China
| | - Yijun Liu
- grid.413107.0Department of Foot and Ankle Surgery, Center for Orthopedic Surgery, The Third Affiliated Hospital of Southern Medical University, Guangzhou, China
| | - Xiaohe Lu
- grid.284723.80000 0000 8877 7471Department of Ophthalmology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Jiali Li
- grid.284723.80000 0000 8877 7471Department of Ophthalmology, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| |
Collapse
|
13
|
Kamel SM, Broekman S, Tessadori F, van Wijk E, Bakkers J. The zebrafish cohesin protein Sgo1 is required for cardiac function and eye development. Dev Dyn 2022; 251:1357-1367. [PMID: 35275424 PMCID: PMC9545960 DOI: 10.1002/dvdy.468] [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: 10/19/2021] [Revised: 03/02/2022] [Accepted: 03/05/2022] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Cohesinopathies is a term that refers to/covers rare genetic diseases caused by mutations in the cohesin complex proteins. The cohesin complex is a multiprotein complex that facilitates different aspects of cell division, gene transcription, DNA damage repair, and chromosome architecture. Shugoshin proteins prevent the cohesin complex from premature dissociation from chromatids during cell division. Patients with a homozygous missense mutation in SGO1, which encodes for Shugoshin1, have problems with normal pacing of the heart and gut. RESULTS To study the role of shugoshin during embryo development, we mutated the zebrafish sgo1 gene. Homozygous sgo1 mutant embryos display various phenotypes related to different organs, including a reduced heart rate accompanied by reduced cardiac function. In addition, sgo1 mutants are vision-impaired as a consequence of structurally defective and partially non-functional photoreceptor cells. Furthermore, the sgo1 mutants display reduced food intake and early lethality. CONCLUSION We have generated a zebrafish model of Sgo1 that showed its importance during organ development and function.
Collapse
Affiliation(s)
- Sarah M. Kamel
- Hubrecht Institute‐KNAW, University Medical Centre UtrechtUtrechtThe Netherlands
| | - Sanne Broekman
- Department of OtorhinolaryngologyRadboud University Medical CenterNijmegenThe Netherlands
- Donders Institute for Brain, Cognition and BehaviorRadboud University Medical CenterNijmegenThe Netherlands
| | - Federico Tessadori
- Hubrecht Institute‐KNAW, University Medical Centre UtrechtUtrechtThe Netherlands
| | - Erwin van Wijk
- Department of OtorhinolaryngologyRadboud University Medical CenterNijmegenThe Netherlands
- Donders Institute for Brain, Cognition and BehaviorRadboud University Medical CenterNijmegenThe Netherlands
| | - Jeroen Bakkers
- Hubrecht Institute‐KNAW, University Medical Centre UtrechtUtrechtThe Netherlands
- Department of Medical Physiology, Division of Heart & LungsUniversity Medical Center UtrechtUtrechtThe Netherlands
- Department of Pediatric Cardiology, Division of PediatricsUniversity Medical Center UtrechtUtrechtThe Netherlands
| |
Collapse
|
14
|
Fogerty J, Song P, Boyd P, Grabinski SE, Hoang T, Reich A, Cianciolo LT, Blackshaw S, Mumm JS, Hyde DR, Perkins BD. Notch Inhibition Promotes Regeneration and Immunosuppression Supports Cone Survival in a Zebrafish Model of Inherited Retinal Dystrophy. J Neurosci 2022; 42:5144-5158. [PMID: 35672150 PMCID: PMC9236296 DOI: 10.1523/jneurosci.0244-22.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/18/2022] [Accepted: 05/13/2022] [Indexed: 12/31/2022] Open
Abstract
Photoreceptor degeneration leads to irreversible vision loss in humans with retinal dystrophies such as retinitis pigmentosa. Whereas photoreceptor loss is permanent in mammals, zebrafish possesses the ability to regenerate retinal neurons and restore visual function. Following acute damage, Müller glia (MG) re-enter the cell cycle and produce multipotent progenitors whose progeny differentiate into mature neurons. Both MG reprogramming and proliferation of retinal progenitor cells require reactive microglia and associated inflammatory signaling. Paradoxically, in zebrafish models of retinal degeneration, photoreceptor death does not induce the MG to reprogram and regenerate lost cells. Here, we used male and female zebrafish cep290 mutants to demonstrate that progressive cone degeneration generates an immune response but does not stimulate MG proliferation. Acute light damage triggered photoreceptor regeneration in cep290 mutants but cones were only restored to prelesion densities. Using irf8 mutant zebrafish, we found that the chronic absence of microglia reduced inflammation and rescued cone degeneration in cep290 mutants. Finally, single-cell RNA-sequencing revealed sustained expression of notch3 in MG of cep290 mutants and inhibition of Notch signaling induced MG to re-enter the cell cycle. Our findings provide new insights on the requirements for MG to proliferate and the potential for immunosuppression to prolong photoreceptor survival.SIGNIFICANCE STATEMENT Inherited retinal degenerations (IRDs) are genetic diseases that lead to the progressive loss of photoreceptors and the permanent loss of vision. Zebrafish can regenerate photoreceptors after acute injury by reprogramming Müller glia (MG) into stem-like cells that produce retinal progenitors, but this regenerative process fails to occur in zebrafish models of IRDs. Here, we show that Notch pathway inhibition can promote photoreceptor regeneration in models of progressive degeneration and that immunosuppression can prevent photoreceptor loss. These results offer insight into the pathways that promote MG-dependent regeneration and the role of inflammation in photoreceptor degeneration.
Collapse
Affiliation(s)
- Joseph Fogerty
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Ping Song
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Patrick Boyd
- Department of Biological Sciences, Center for Zebrafish Research, and Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, Indiana 46556
| | - Sarah E Grabinski
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Thanh Hoang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Adrian Reich
- Florida Research and Innovation Center, Lerner Research Institute, Cleveland Clinic, Port St. Lucie, Florida 34987
| | - Lauren T Cianciolo
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Jeff S Mumm
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - David R Hyde
- Department of Biological Sciences, Center for Zebrafish Research, and Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, Indiana 46556
| | - Brian D Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio 44195
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio 44195
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, Ohio 44195
| |
Collapse
|
15
|
Miles A, Blair C, Emili A, Tropepe V. Usher syndrome type 1-associated gene, pcdh15b, is required for photoreceptor structural integrity in zebrafish. Dis Model Mech 2021; 14:272551. [PMID: 34668518 PMCID: PMC8669488 DOI: 10.1242/dmm.048965] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 10/13/2021] [Indexed: 12/23/2022] Open
Abstract
Blindness associated with Usher syndrome type 1 (USH1) is typically characterized as rod photoreceptor degeneration, followed by secondary loss of cones. The mechanisms leading to blindness are unknown because most genetic mouse models only recapitulate auditory defects. We generated zebrafish mutants for one of the USH1 genes, protocadherin-15b (pcdh15b), a putative cell adhesion molecule. Zebrafish Pcdh15 is expressed exclusively in photoreceptors within calyceal processes (CPs), at the base of the outer segment (OS) and within the synapse. In our mutants, rod and cone photoreceptor integrity is compromised, with early and progressively worsening abnormal OS disc growth and detachment, in part due to weakening CP contacts. These effects were attenuated or exacerbated by growth in dark and bright-light conditions, respectively. We also describe novel evidence for structural defects in synapses of pcdh15b mutant photoreceptors. Cell death does not accompany these defects at early stages, suggesting that photoreceptor structural defects, rather than overt cell loss, may underlie vision deficits. Thus, we present the first genetic animal model of a PCDH15-associated retinopathy that can be used to understand the aetiology of blindness in USH1. This article has an associated First Person interview with the first author of the paper. Summary: We present one of the first genetic animal mutants for PCDH15 that displays a severe, early retinopathy and suggests that zebrafish could be a useful model for PCDH15-associated retinal phenotypes.
Collapse
Affiliation(s)
- Amanda Miles
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Clarke Blair
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| | - Andrew Emili
- Center for Network Systems Biology, Boston University, Boston, MA 02118, USA
| | - Vincent Tropepe
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
| |
Collapse
|
16
|
Adherent but Not Suspension-Cultured Embryoid Bodies Develop into Laminated Retinal Organoids. J Dev Biol 2021; 9:jdb9030038. [PMID: 34564087 PMCID: PMC8482155 DOI: 10.3390/jdb9030038] [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: 07/13/2021] [Revised: 08/31/2021] [Accepted: 09/08/2021] [Indexed: 11/23/2022] Open
Abstract
Human induced pluripotent stem cells (iPSCs) are differentiated into three-dimensional (3D) retinal organoids to study retinogenesis and diseases that would otherwise be impossible. The complexity and low yield in current protocols remain a technical challenge, particularly for inexperienced personnel. Differentiation protocols require labor-intensive and time-consuming dissection of optic vesicles (OVs). Here we compare this method with a suspension method of developing retinal organoids. iPSCs were differentiated with standard protocols but the suspension-grown method omitted the re-plating of embryoid bodies and dissection of OVs. All other media and treatments were identical between developmental methods. Developmental maturation was evaluated with RT-qPCR and immunocytochemistry. Dissection- and suspension-derived retinal organoids displayed temporal biogenesis of retinal cell types. Differences in retinal organoids generated by the two methods of differentiation included temporal developmental and the organization of neural retina layers. Retinal organoids grown in suspension showed delayed development and disorganized retinal layers compared to the dissected retinal organoids. We found that omitting the re-plating of EBs to form OVs resulted in numerous OVs that were easy to identify and matured along a retinal lineage. While more efficient, the suspension method led to retinal organoids with disorganized retinal layers compared to those obtained using conventional dissection protocols.
Collapse
|
17
|
Hong Y, Luo Y. Zebrafish Model in Ophthalmology to Study Disease Mechanism and Drug Discovery. Pharmaceuticals (Basel) 2021; 14:ph14080716. [PMID: 34451814 PMCID: PMC8400593 DOI: 10.3390/ph14080716] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/16/2021] [Accepted: 07/21/2021] [Indexed: 12/14/2022] Open
Abstract
Visual impairment and blindness are common and seriously affect people’s work and quality of life in the world. Therefore, the effective therapies for eye diseases are of high priority. Zebrafish (Danio rerio) is an alternative vertebrate model as a useful tool for the mechanism elucidation and drug discovery of various eye disorders, such as cataracts, glaucoma, diabetic retinopathy, age-related macular degeneration, photoreceptor degeneration, etc. The genetic and embryonic accessibility of zebrafish in combination with a behavioral assessment of visual function has made it a very popular model in ophthalmology. Zebrafish has also been widely used in ocular drug discovery, such as the screening of new anti-angiogenic compounds or neuroprotective drugs, and the oculotoxicity test. In this review, we summarized the applications of zebrafish as the models of eye disorders to study disease mechanism and investigate novel drug treatments.
Collapse
Affiliation(s)
| | - Yan Luo
- Correspondence: ; Tel.: +86-020-87335931
| |
Collapse
|
18
|
Retinal Stem Cell 'Retirement Plans': Growth, Regulation and Species Adaptations in the Retinal Ciliary Marginal Zone. Int J Mol Sci 2021; 22:ijms22126528. [PMID: 34207050 PMCID: PMC8234741 DOI: 10.3390/ijms22126528] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 06/11/2021] [Accepted: 06/14/2021] [Indexed: 12/12/2022] Open
Abstract
The vertebrate retina develops from a specified group of precursor cells that adopt distinct identities and generate lineages of either the neural retina, retinal pigmented epithelium, or ciliary body. In some species, including teleost fish and amphibians, proliferative cells with stem-cell-like properties capable of continuously supplying new retinal cells post-embryonically have been characterized and extensively studied. This region, termed the ciliary or circumferential marginal zone (CMZ), possibly represents a conserved retinal stem cell niche. In this review, we highlight the research characterizing similar CMZ-like regions, or stem-like cells located at the peripheral margin, across multiple different species. We discuss the proliferative parameters, multipotency and growth mechanisms of these cells to understand how they behave in vivo and how different molecular factors and signalling networks converge at the CMZ niche to regulate their activity. The evidence suggests that the mature retina may have a conserved propensity for homeostatic growth and plasticity and that dysfunction in the regulation of CMZ activity may partially account for dystrophic eye growth diseases such as myopia and hyperopia. A better understanding of the properties of CMZ cells will enable important insight into how an endogenous generative tissue compartment can adapt to altered retinal physiology and potentially even restore vision loss caused by retinal degenerative conditions.
Collapse
|
19
|
Turkalj B, Quallich D, Bessert DA, Kramer AC, Cook TA, Thummel R. Development and characterization of a chronic photoreceptor degeneration model in adult zebrafish that does not trigger a regenerative response. Exp Eye Res 2021; 209:108630. [PMID: 34029596 DOI: 10.1016/j.exer.2021.108630] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/05/2021] [Accepted: 05/16/2021] [Indexed: 11/29/2022]
Abstract
Zebrafish (Danio rerio) have become a highly-utilized model system in the field of regenerative biology because of their endogenous ability to regenerate many tissues and organs, including the retina. The vast majority of previous research on retinal regeneration in adult zebrafish utilizes acute methodologies for retinal damage. Acute retinal cell death triggers a reactive gliosis response of Müller glia (MG), the resident macroglia of the retina. In addition, each activated MG undergoes asymmetric cell division to produce a neuronal progenitor, which continues to divide and ultimately gives rise to new retinal neurons. Studies using these approaches have uncovered many crucial mechanisms by which MG respond to acute damage. However, they may not adequately mimic the chronic neuronal degeneration observed in many human retinal degenerative diseases. The current study aimed to develop a new long-term, chronic photoreceptor damage and degeneration model in adult zebrafish. Comparing the subsequent cellular responses to that of the commonly-used acute high-intensity model, we found that low, continuous light exposure damaged the outer segments of both rod and cone photoreceptors, but did not result in significant apoptotic cell death, MG gliosis, or MG cell-cycle re-entry. Instead, chronic light nearly completely truncated photoreceptor outer segments and resulted in a recruitment of microglia to the area. Together, these studies present a chronic photoreceptor model that can be performed in a relatively short time frame (21 days), that may lend insight into the cellular events underlying non-regenerative photoreceptor degeneration observed in other model systems.
Collapse
Affiliation(s)
- Brooke Turkalj
- Wayne State University School of Medicine, Department of Ophthalmology, Visual and Anatomical Sciences, Detroit, MI, USA.
| | - Danielle Quallich
- Wayne State University School of Medicine, Department of Ophthalmology, Visual and Anatomical Sciences, Detroit, MI, USA.
| | - Denise A Bessert
- Wayne State University School of Medicine, Department of Ophthalmology, Visual and Anatomical Sciences, Detroit, MI, USA.
| | - Ashley C Kramer
- Wayne State University School of Medicine, Department of Ophthalmology, Visual and Anatomical Sciences, Detroit, MI, USA.
| | - Tiffany A Cook
- Wayne State University School of Medicine, Department of Ophthalmology, Visual and Anatomical Sciences, Detroit, MI, USA; Wayne State University School of Medicine, Center for Molecular Medicine and Genetics, Detroit, MI, USA.
| | - Ryan Thummel
- Wayne State University School of Medicine, Department of Ophthalmology, Visual and Anatomical Sciences, Detroit, MI, USA.
| |
Collapse
|