1
|
Goyal S, Tibrewal S, Ratna R, Vanita V. Genetic and environmental factors contributing to anophthalmia and microphthalmia: Current understanding and future directions. World J Clin Pediatr 2025; 14:101982. [DOI: 10.5409/wjcp.v14.i2.101982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2024] [Revised: 02/19/2025] [Accepted: 02/25/2025] [Indexed: 03/18/2025] Open
Abstract
Anophthalmia is defined as a complete absence of one eye or both the eyes, while microphthalmia represents the presence of a small eye within the orbit. The estimated birth prevalence for anophthalmia is approximately 3 per 100000 live births, and for microphthalmia, it is around 14 per 100000 live births. However, combined evidence suggests that the prevalence of these malformations could be as high as 30 per 100000 individuals. Microphthalmia is reported to occur in 3.2% to 11.2% of blind children. Anophthalmia and microphthalmia (A/M) are part of a phenotypic spectrum alongside ocular coloboma, hypothesized to share a common genetic basis. Both A/M can occur in isolation or as part of a syndrome. Their complex etiology involves chromosomal aberrations, monogenic inheritance pattern, and the contribution of environmental factors such as gestational-acquired infections, maternal vitamin A deficiency (VAD), exposure to X-rays, solvent misuse, and thalidomide exposure. A/M exhibit significant clinical and genetic heterogeneity with over 90 genes identified so far. Familial cases of A/M have a complex genetic basis, including all Mendelian modes of inheritance, i.e., autosomal dominant, recessive, and X-linked. Most cases arise sporadically due to de novo mutations. Examining gene expression during eye development and the effects of various environmental variables will help us better understand the phenotypic heterogeneity found in A/M, leading to more effective diagnosis and management strategies. The present review focuses on key genetic factors, developmental abnormalities, and environmental modifiers linked with A/M. It also emphasizes at potential research areas including multiomic methods and disease modeling with induced pluripotent stem cell technologies, which aim to create innovative treatment options.
Collapse
Affiliation(s)
- Shiwali Goyal
- Department of Ophthalmic Genetics and Visual Function Branch, National Eye Institute, Rockville, MD 20852, United States
| | - Shailja Tibrewal
- Department of Pediatric Ophthalmology, Dr. Shroff’s Charity Eye Hospital, New Delhi 110002, Delhi, India
- Department of Ocular Genetics (Center for Unknown and Rare Eye Diseases), Dr. Shroff’s Charity Eye Hospital, New Delhi 110002, Delhi, India
| | - Ria Ratna
- Department of Ocular Genetics (Center for Unknown and Rare Eye Diseases), Dr. Shroff’s Charity Eye Hospital, New Delhi 110002, Delhi, India
| | - Vanita Vanita
- Department of Human Genetics, Guru Nanak Dev University, Amritsar 143005, Punjab, India
| |
Collapse
|
2
|
Herstine JA, Mensh J, Coffman E, George SM, Herman K, Martin JB, Zatari A, Chandler HL, Kozmik Z, Drysdale TA, Bridgewater D, Plageman TF. Shroom3 facilitates optic fissure closure via tissue alignment and reestablishment of apical-basal polarity during epithelial fusion. Dev Biol 2025; 522:91-105. [PMID: 40113025 DOI: 10.1016/j.ydbio.2025.03.008] [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: 10/09/2024] [Revised: 02/24/2025] [Accepted: 03/15/2025] [Indexed: 03/22/2025]
Abstract
Optic cup morphogenesis is a complex process involving cellular behaviors such as epithelial folding, cell shape changes, proliferation, and tissue fusion. Disruptions to these processes can lead to an ocular coloboma, a congenital defect where the optic fissure fails to close. This study investigates the role of Shroom3, a protein implicated in epithelial morphogenesis, in mouse embryos during optic cup development. It was observed that Shroom3 is apically localized in the neural retina and retinal pigmented epithelium, and its deficiency leads to a both a conventional coloboma phenotype characterized by a gap in pigmented tissue as well as a unique type of coloboma where an ectopic ventral fold of neural tissue is present. Increased apical areas of both neural retina and retinal pigmented epithelial cells are present in the absence of Shroom3 leading to a greater apical surface area and disruption of optic fissure alignment. Neural retina specific gene ablation revealed that Shroom3 function in the RPE is likely sufficient to facilitate tissue alignment and permit fusion. However, the fusion process is ultimately disturbed due to a failure of the neural tissue to reestablish apical-basal polarity. Furthermore, it is demonstrated that Shroom3 deficiency also affects other epithelial fusion events in the embryo that rely on polarity reestablishment, such as lens vesicle separation, eyelid formation, and secondary palate closure. These findings highlight the importance of Shroom3 during optic cup morphogenesis, aid our understanding of optic fissure closure and coloboma formation, and implicates a role for Shroom3 in regulating apical-basal polarity.
Collapse
Affiliation(s)
| | - Jordyn Mensh
- College of Optometry, The Ohio State University, Columbus, OH, USA
| | - Electra Coffman
- College of Optometry, The Ohio State University, Columbus, OH, USA
| | | | - Kenneth Herman
- College of Optometry, The Ohio State University, Columbus, OH, USA
| | - Jessica B Martin
- College of Optometry, The Ohio State University, Columbus, OH, USA
| | - Ali Zatari
- College of Optometry, The Ohio State University, Columbus, OH, USA
| | | | - Zbynek Kozmik
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Thomas A Drysdale
- Department of Physiology and Pharmacology, Schulich School of Medicine & Dentistry, Western University, London, Ontario, Canada
| | - Darren Bridgewater
- Department of Pathology and Molecular Medicine, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada
| | | |
Collapse
|
3
|
Claussen N, Regis C, Wopat S, Streichan S. Blender tissue cartography: an intuitive tool for the analysis of dynamic 3D microscopy data. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2025:2025.02.04.636523. [PMID: 39975091 PMCID: PMC11838551 DOI: 10.1101/2025.02.04.636523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2025]
Abstract
Tissue cartography extracts and cartographically projects surfaces from volumetric biological image data. This turns 3D- into 2D data which is much easier to visualize, analyze, and computationally process. Tissue cartography has proven particularly useful in developmental biology by taking advantage of the sheet-like organization of many biological tissues. However, existing software tools for tissue cartography are limited in the type of geometries they can handle and difficult for non-experts to use and extend. Here, we describe blender_tissue_cartography (btc), a tissue cartography add-on for the popular 3D creation software Blender. btc makes tissue cartography user-friendly via a graphical user interface and harnesses powerful algorithms from the computer graphics community for biological image analysis. The btc GUI enables interactive analysis and visualization without requiring any programming expertise, while an accompanying Python library allows expert users to create custom analysis pipelines. Both the add-on and the Python library are highly modular and fully documented, including interactive Jupyter Notebook tutorials. btc features a general-purpose pipeline for time-lapse data in which the user graphically defines a cartographic projection for a single key frame, which is propagated to all other frames via surface-to-surface alignment algorithms. The btc differential geometry module allows mathematically correcting for cartographic distortion, enabling faithful 3D measurements in 2D cartographic projections, including for vector fields like tissue flow fields. We demonstrate btc on diverse and complex tissue shapes from Drosophila, stem-cell-based organoids, Arabidopsis, and zebrafish.
Collapse
Affiliation(s)
- Nikolas Claussen
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | | | - Susan Wopat
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Sebastian Streichan
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
- Department of Bioengineering, University of California Santa Barbara, Santa Barbara, California 93106, USA
| |
Collapse
|
4
|
Hofstetter KS, Haas PM, Kuntz JP, Zheng Y, Fuhrmann S. Loss of Cdc42 causes abnormal optic cup morphogenesis and microphthalmia in mouse. Front Cell Neurosci 2024; 18:1474010. [PMID: 39650797 PMCID: PMC11622195 DOI: 10.3389/fncel.2024.1474010] [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: 07/31/2024] [Accepted: 10/31/2024] [Indexed: 12/11/2024] Open
Abstract
Congenital ocular malformations originate from defective morphogenesis during early eye development and cause 25% of childhood blindness. Formation of the eye is a multi-step, dynamic process; it involves evagination of the optic vesicle, followed by distal and ventral invagination, leading to the formation of a two-layered optic cup with a transient optic fissure. These tissue folding events require extensive changes in cell shape and tissue growth mediated by cytoskeleton mechanics and intercellular adhesion. We hypothesized that the Rho GTPase Cdc42 may be an essential, convergent effector downstream of key regulatory factors required for ocular morphogenesis. CDC42 controls actin remodeling, apicobasal polarity, and junction assembly. Here we identify a novel essential function for Cdc42 during eye morphogenesis in mouse; in Cdc42 mutant eyes expansion of the ventral optic cup is arrested, resulting in microphthalmia and a wide coloboma. Our analyses show that Cdc42 is required for expression of the polarity effector proteins PRKCZ and PARD6, intercellular junction protein tight junction protein 1, β-catenin, actin cytoskeleton F-actin, and contractile protein phospho myosin light chain 2. Expression of RPE fate determinants OTX2 and MITF, and formation of the RPE layer are severely affected in the temporal domain of the proximal optic cup. EdU incorporation is significantly downregulated. In addition, mitotic retinal progenitor cells mislocalize deeper, basal regions, likely contributing to decreased proliferation. We propose that morphogenesis of the ventral optic cup requires Cdc42 function for coordinated optic cup expansion and establishment of subretinal space, tissue tension, and differentiation of the ventral RPE layer.
Collapse
Affiliation(s)
- Katrina S. Hofstetter
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Paula M. Haas
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Jonathon P. Kuntz
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Yi Zheng
- Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Sabine Fuhrmann
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Cell and Developmental Biology, Vanderbilt University Medical School, Nashville, TN, United States
| |
Collapse
|
5
|
Hofstetter KS, Haas PM, Kuntz JP, Zheng Y, Fuhrmann S. Loss of Cdc42 causes abnormal optic cup morphogenesis and microphthalmia in mouse. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.10.20.619331. [PMID: 39484575 PMCID: PMC11526912 DOI: 10.1101/2024.10.20.619331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/03/2024]
Abstract
Congenital ocular malformations originate from defective morphogenesis during early eye development and cause 25% of childhood blindness. Formation of the eye is a multi-step, dynamic process; it involves evagination of the optic vesicle, followed by distal and ventral invagination, leading to the formation of a two-layered optic cup with a transient optic fissure. These tissue folding events require extensive changes in cell shape and tissue growth mediated by cytoskeleton mechanics and intercellular adhesion. We hypothesized that the Rho GTPase Cdc42 may be an essential, convergent effector downstream of key regulatory factors required for ocular morphogenesis. CDC42 controls actin remodeling, apicobasal polarity, and junction assembly. Here we identify a novel essential function for Cdc42 during eye morphogenesis in mouse; in Cdc42 mutant eyes expansion of the ventral optic cup is arrested, resulting in microphthalmia and a wide coloboma. Our analyses show that Cdc42 is required for expression of the polarity effector proteins PRKCZ and PARD6, intercellular junction protein tight junction protein 1, β-catenin, actin cytoskeleton F-actin, and contractile protein phospho myosin light chain 2. Expression of RPE fate determinants OTX2 and MITF, and formation of the RPE layer are severely affected in the temporal domain of the proximal optic cup. EdU incorporation is significantly downregulated. In addition, mitotic retinal progenitor cells mis-localized deeper, basal regions, likely contributing to decreased proliferation. We propose that morphogenesis of the ventral optic cup requires Cdc42 function for coordinated optic cup expansion and establishment of subretinal space, tissue tension, and differentiation of the ventral RPE layer.
Collapse
Affiliation(s)
- Katrina S. Hofstetter
- Dept. of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN
| | - Paula M. Haas
- Dept. of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN
| | - Jonathon P. Kuntz
- Dept. of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN
| | - Yi Zheng
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Sabine Fuhrmann
- Dept. of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN
- Dept. of Cell and Developmental Biology, Vanderbilt University Medical School; Nashville, TN
| |
Collapse
|
6
|
Baptista FI, Ambrósio AF. Tracing the influence of prenatal risk factors on the offspring retina: Focus on development and putative long-term consequences. Eur J Clin Invest 2024; 54:e14266. [PMID: 38864773 DOI: 10.1111/eci.14266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/10/2024] [Accepted: 05/29/2024] [Indexed: 06/13/2024]
Abstract
BACKGROUND Pregnancy represents a window of vulnerability to fetal development. Disruptions in the prenatal environment during this crucial period can increase the risk of the offspring developing diseases over the course of their lifetime. The central nervous system (CNS) has been shown to be particularly susceptible to changes during crucial developmental windows. To date, research focused on disruptions in the development of the CNS has predominantly centred on the brain, revealing a correlation between exposure to prenatal risk factors and the onset of neuropsychiatric disorders. Nevertheless, some studies indicate that the retina, which is part of the CNS, is also vulnerable to in utero alterations during pregnancy. Such changes may affect neuronal, glial and vascular components of the retina, compromising retinal structure and function and possibly impairing visual function. METHODS A search in the PubMed database was performed, and any literature concerning prenatal risk factors (drugs, diabetes, unbalanced diet, infection, glucocorticoids) affecting the offspring retina were included. RESULTS This review collects evidence on the cellular, structural and functional changes occurring in the retina triggered by maternal risk factors during pregnancy. We highlight the adverse impact on retinal development and its long-lasting effects, providing a critical analysis of the current knowledge while underlining areas for future research. CONCLUSIONS Appropriate recognition of the prenatal risk factors that negatively impact the developing retina may provide critical clues for the design of preventive strategies and for early therapeutic intervention that could change retinal pathology in the progeny.
Collapse
Affiliation(s)
- Filipa I Baptista
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal
| | - António F Ambrósio
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), Coimbra, Portugal
- Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| |
Collapse
|
7
|
Walker MF, Zhang J, Steiner W, Ku PI, Zhu JF, Michaelson Z, Yen YC, Lee A, Long AB, Casey MJ, Poddar A, Nelson IB, Arveseth CD, Nagel F, Clough R, LaPotin S, Kwan KM, Schulz S, Stewart RA, Tesmer JJG, Caspary T, Subramanian R, Ge X, Myers BR. GRK2 kinases in the primary cilium initiate SMOOTHENED-PKA signaling in the Hedgehog cascade. PLoS Biol 2024; 22:e3002685. [PMID: 39138140 PMCID: PMC11322411 DOI: 10.1371/journal.pbio.3002685] [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: 06/06/2023] [Accepted: 05/21/2024] [Indexed: 08/15/2024] Open
Abstract
During Hedgehog (Hh) signal transduction in development and disease, the atypical G protein-coupled receptor (GPCR) SMOOTHENED (SMO) communicates with GLI transcription factors by binding the protein kinase A catalytic subunit (PKA-C) and physically blocking its enzymatic activity. Here, we show that GPCR kinase 2 (GRK2) orchestrates this process during endogenous mouse and zebrafish Hh pathway activation in the primary cilium. Upon SMO activation, GRK2 rapidly relocalizes from the ciliary base to the shaft, triggering SMO phosphorylation and PKA-C interaction. Reconstitution studies reveal that GRK2 phosphorylation enables active SMO to bind PKA-C directly. Lastly, the SMO-GRK2-PKA pathway underlies Hh signal transduction in a range of cellular and in vivo models. Thus, GRK2 phosphorylation of ciliary SMO and the ensuing PKA-C binding and inactivation are critical initiating events for the intracellular steps in Hh signaling. More broadly, our study suggests an expanded role for GRKs in enabling direct GPCR interactions with diverse intracellular effectors.
Collapse
Affiliation(s)
- Madison F. Walker
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Jingyi Zhang
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, California, United States of America
| | - William Steiner
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Pei-I Ku
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ju-Fen Zhu
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Zachary Michaelson
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Yu-Chen Yen
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Annabel Lee
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Alyssa B. Long
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Mattie J. Casey
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Abhishek Poddar
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Isaac B. Nelson
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Corvin D. Arveseth
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | | | - Ryan Clough
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Sarah LaPotin
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Kristen M. Kwan
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Stefan Schulz
- 7TM Antibodies GmbH, Jena, Germany
- Institute of Pharmacology and Toxicology, University Hospital Jena, Jena, Germany
| | - Rodney A. Stewart
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - John J. G. Tesmer
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana, United States of America
| | - Tamara Caspary
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Radhika Subramanian
- Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, USA; Department of Genetics, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Xuecai Ge
- Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, California, United States of America
| | - Benjamin R. Myers
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Bioengineering, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| |
Collapse
|
8
|
Eintracht J, Owen N, Harding P, Moosajee M. Disruption of common ocular developmental pathways in patient-derived optic vesicle models of microphthalmia. Stem Cell Reports 2024; 19:839-858. [PMID: 38821055 PMCID: PMC11390689 DOI: 10.1016/j.stemcr.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 04/30/2024] [Accepted: 05/02/2024] [Indexed: 06/02/2024] Open
Abstract
Genetic perturbations influencing early eye development can result in microphthalmia, anophthalmia, and coloboma (MAC). Over 100 genes are associated with MAC, but little is known about common disease mechanisms. In this study, we generated induced pluripotent stem cell (iPSC)-derived optic vesicles (OVs) from two unrelated microphthalmia patients and healthy controls. At day 20, 35, and 50, microphthalmia patient OV diameters were significantly smaller, recapitulating the "small eye" phenotype. RNA sequencing (RNA-seq) analysis revealed upregulation of apoptosis-initiating and extracellular matrix (ECM) genes at day 20 and 35. Western blot and immunohistochemistry revealed increased expression of lumican, nidogen, and collagen type IV, suggesting ECM overproduction. Increased apoptosis was observed in microphthalmia OVs with reduced phospho-histone 3 (pH3+) cells confirming decreased cell proliferation at day 35. Pharmacological inhibition of caspase-8 activity with Z-IETD-FMK decreased apoptosis in one patient model, highlighting a potential therapeutic approach. These data reveal shared pathophysiological mechanisms contributing to a microphthalmia phenotype.
Collapse
Affiliation(s)
| | | | | | - Mariya Moosajee
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; Moorfields Eye Hospital NHS Foundation Trust, London EC1V 9EL, UK; Francis Crick Institute, London NW1 1AT, UK.
| |
Collapse
|
9
|
Walker MF, Zhang J, Steiner W, Ku PI, Zhu JF, Michaelson Z, Yen YC, Lee A, Long AB, Casey MJ, Poddar A, Nelson IB, Arveseth CD, Nagel F, Clough R, LaPotin S, Kwan KM, Schulz S, Stewart RA, Tesmer JJG, Caspary T, Subramanian R, Ge X, Myers BR. GRK2 Kinases in the Primary Cilium Initiate SMOOTHENED-PKA Signaling in the Hedgehog Cascade. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.05.10.540226. [PMID: 37214942 PMCID: PMC10197709 DOI: 10.1101/2023.05.10.540226] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
During Hedgehog (Hh) signal transduction in development and disease, the atypical G protein-coupled receptor (GPCR) SMOOTHENED (SMO) communicates with GLI transcription factors by binding the protein kinase A catalytic subunit (PKA-C) and physically blocking its enzymatic activity. Here we show that GPCR kinase 2 (GRK2) orchestrates this process during endogenous Hh pathway activation in the vertebrate primary cilium. Upon SMO activation, GRK2 rapidly relocalizes from the ciliary base to the shaft, triggering SMO phosphorylation and PKA-C interaction. Reconstitution studies reveal that GRK2 phosphorylation enables active SMO to bind PKA-C directly. Lastly, the SMO-GRK2-PKA pathway underlies Hh signal transduction in a range of cellular and in vivo models. Thus, GRK2 phosphorylation of ciliary SMO, and the ensuing PKA-C binding and inactivation, are critical initiating events for the intracellular steps in Hh signaling. More broadly, our study suggests an expanded role for GRKs in enabling direct GPCR interactions with diverse intracellular effectors.
Collapse
|
10
|
Caruso L, Fields M, Rimondi E, Zauli G, Longo G, Marcuzzi A, Previati M, Gonelli A, Zauli E, Milani D. Classical and Innovative Evidence for Therapeutic Strategies in Retinal Dysfunctions. Int J Mol Sci 2024; 25:2124. [PMID: 38396799 PMCID: PMC10889839 DOI: 10.3390/ijms25042124] [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: 12/29/2023] [Revised: 02/05/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
The human retina is a complex anatomical structure that has no regenerative capacity. The pathogenesis of most retinopathies can be attributed to inflammation, with the activation of the inflammasome protein platform, and to the impact of oxidative stress on the regulation of apoptosis and autophagy/mitophagy in retinal cells. In recent years, new therapeutic approaches to treat retinopathies have been investigated. Experimental data suggest that the secretome of mesenchymal cells could reduce oxidative stress, autophagy, and the apoptosis of retinal cells, and in turn, the secretome of the latter could induce changes in mesenchymal cells. Other studies have evidenced that noncoding (nc)RNAs might be new targets for retinopathy treatment and novel disease biomarkers since a correlation has been found between ncRNA levels and retinopathies. A new field to explore is the interaction observed between the ocular and intestinal microbiota; indeed, recent findings have shown that the alteration of gut microbiota seems to be linked to ocular diseases, suggesting a gut-eye axis. To explore new therapeutical strategies for retinopathies, it is important to use proper models that can mimic the complexity of the retina. In this context, retinal organoids represent a good model for the study of the pathophysiology of the retina.
Collapse
Affiliation(s)
- Lorenzo Caruso
- Department of Environmental and Prevention Sciences, University of Ferrara, 44121 Ferrara, Italy; (L.C.); (A.G.)
| | - Matteo Fields
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (M.F.); (G.L.); (A.M.); (M.P.); (D.M.)
| | - Erika Rimondi
- Department of Translational Medicine and LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
| | - Giorgio Zauli
- Research Department, King Khaled Eye Specialist Hospital, Riyadh 11462, Saudi Arabia;
| | - Giovanna Longo
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (M.F.); (G.L.); (A.M.); (M.P.); (D.M.)
| | - Annalisa Marcuzzi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (M.F.); (G.L.); (A.M.); (M.P.); (D.M.)
| | - Maurizio Previati
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (M.F.); (G.L.); (A.M.); (M.P.); (D.M.)
| | - Arianna Gonelli
- Department of Environmental and Prevention Sciences, University of Ferrara, 44121 Ferrara, Italy; (L.C.); (A.G.)
| | - Enrico Zauli
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (M.F.); (G.L.); (A.M.); (M.P.); (D.M.)
| | - Daniela Milani
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (M.F.); (G.L.); (A.M.); (M.P.); (D.M.)
| |
Collapse
|
11
|
Rasys AM, Wegerski A, Trainor PA, Hufnagel RB, Menke DB, Lauderdale JD. Dynamic changes in ocular shape during human development and its implications for retina fovea formation. Bioessays 2024; 46:e2300054. [PMID: 38037292 PMCID: PMC11614145 DOI: 10.1002/bies.202300054] [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: 03/27/2023] [Revised: 10/10/2023] [Accepted: 10/24/2023] [Indexed: 12/02/2023]
Abstract
The human fovea is known for its distinctive pit-like appearance, which results from the displacement of retinal layers superficial to the photoreceptors cells. The photoreceptors are found at high density within the foveal region but not the surrounding retina. Efforts to elucidate the mechanisms responsible for these unique features have ruled out cell death as an explanation for pit formation and changes in cell proliferation as the cause of increased photoreceptor density. These findings have led to speculation that mechanical forces acting within and on the retina during development underly the formation of foveal architecture. Here we review eye morphogenesis and retinal remodeling in human embryonic development. Our meta-analysis of the literature suggests that fovea formation is a protracted process involving dynamic changes in ocular shape that start early and continue throughout most of human embryonic development. From these observations, we propose a new model for fovea development.
Collapse
Affiliation(s)
- Ashley M. Rasys
- Department of Cellular Biology, The University of Georgia, Athens, Georgia, USA
| | - Andrew Wegerski
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Paul A. Trainor
- Stowers Institute for Medical Research, Kansas City, Missouri, USA
- Department of Anatomy & Cell Biology, The University of Kansas School of Medicine, Kansas City, Kansas, USA
| | - Robert B. Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Douglas B. Menke
- Department of Genetics, The University of Georgia, Athens, Georgia, USA
| | - James D. Lauderdale
- Department of Cellular Biology, The University of Georgia, Athens, Georgia, USA
- Neuroscience Division of the Biomedical and Health Sciences Institute, The University of Georgia, Athens, Georgia, USA
| |
Collapse
|
12
|
Sokolova N, Zilova L, Wittbrodt J. Unravelling the link between embryogenesis and adult stem cell potential in the ciliary marginal zone: A comparative study between mammals and teleost fish. Cells Dev 2023; 174:203848. [PMID: 37172718 DOI: 10.1016/j.cdev.2023.203848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/03/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023]
Abstract
The discovery and study of adult stem cells have revolutionized regenerative medicine by offering new opportunities for treating various medical conditions. Anamniote stem cells, which retain their full proliferative capacity and full differentiation range throughout their lifetime, harbour a greater potential compared to mammalian adult stem cells, which only exhibit limited stem cell potential. Therefore, understanding the mechanisms underlying these differences is of significant interest. In this review, we examine the similarities and differences of adult retinal stem cells in anamniotes and mammals, from their embryonic stages in the optic vesicle to their residence in the postembryonic retinal stem cell niche, the ciliary marginal zone located in the retinal periphery. In anamniotes, developing precursors of retinal stem cells are exposed to various environmental cues during their migration in the complex morphogenetic remodelling of the optic vesicle to the optic cup. In contrast, their mammalian counterparts in the retinal periphery are primarily instructed by neighbouring tissues once they are in place. We explore the distinct modes of optic cup morphogenesis in mammals and teleost fish and highlight molecular mechanisms governing morphogenesis and stem cells instruction. The review concludes with the molecular mechanisms of ciliary marginal zone formation and offers a perspective on the impact of comparative single cell transcriptomic studies to reveal the evolutionary similarities and differences.
Collapse
Affiliation(s)
- Natalia Sokolova
- Centre for Organismal Studies Heidelberg, Germany; Heidelberg Biosciences International Graduate School, Germany
| | - Lucie Zilova
- Centre for Organismal Studies Heidelberg, Germany.
| | | |
Collapse
|
13
|
Cardozo MJ, Sánchez-Bustamante E, Bovolenta P. Optic cup morphogenesis across species and related inborn human eye defects. Development 2023; 150:dev200399. [PMID: 36714981 PMCID: PMC10110496 DOI: 10.1242/dev.200399] [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: 01/31/2023]
Abstract
The vertebrate eye is shaped as a cup, a conformation that optimizes vision and is acquired early in development through a process known as optic cup morphogenesis. Imaging living, transparent teleost embryos and mammalian stem cell-derived organoids has provided insights into the rearrangements that eye progenitors undergo to adopt such a shape. Molecular and pharmacological interference with these rearrangements has further identified the underlying molecular machineries and the physical forces involved in this morphogenetic process. In this Review, we summarize the resulting scenarios and proposed models that include common and species-specific events. We further discuss how these studies and those in environmentally adapted blind species may shed light on human inborn eye malformations that result from failures in optic cup morphogenesis, including microphthalmia, anophthalmia and coloboma.
Collapse
Affiliation(s)
- Marcos J. Cardozo
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| | - Elena Sánchez-Bustamante
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| | - Paola Bovolenta
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| |
Collapse
|
14
|
Laminin-111 mutant studies reveal a hierarchy within laminin-111 genes in their requirement for basal epithelial tissue folding. Dev Biol 2022; 492:172-186. [DOI: 10.1016/j.ydbio.2022.10.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/29/2022] [Accepted: 10/10/2022] [Indexed: 11/21/2022]
|
15
|
Diacou R, Nandigrami P, Fiser A, Liu W, Ashery-Padan R, Cvekl A. Cell fate decisions, transcription factors and signaling during early retinal development. Prog Retin Eye Res 2022; 91:101093. [PMID: 35817658 PMCID: PMC9669153 DOI: 10.1016/j.preteyeres.2022.101093] [Citation(s) in RCA: 58] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 12/30/2022]
Abstract
The development of the vertebrate eyes is a complex process starting from anterior-posterior and dorso-ventral patterning of the anterior neural tube, resulting in the formation of the eye field. Symmetrical separation of the eye field at the anterior neural plate is followed by two symmetrical evaginations to generate a pair of optic vesicles. Next, reciprocal invagination of the optic vesicles with surface ectoderm-derived lens placodes generates double-layered optic cups. The inner and outer layers of the optic cups develop into the neural retina and retinal pigment epithelium (RPE), respectively. In vitro produced retinal tissues, called retinal organoids, are formed from human pluripotent stem cells, mimicking major steps of retinal differentiation in vivo. This review article summarizes recent progress in our understanding of early eye development, focusing on the formation the eye field, optic vesicles, and early optic cups. Recent single-cell transcriptomic studies are integrated with classical in vivo genetic and functional studies to uncover a range of cellular mechanisms underlying early eye development. The functions of signal transduction pathways and lineage-specific DNA-binding transcription factors are dissected to explain cell-specific regulatory mechanisms underlying cell fate determination during early eye development. The functions of homeodomain (HD) transcription factors Otx2, Pax6, Lhx2, Six3 and Six6, which are required for early eye development, are discussed in detail. Comprehensive understanding of the mechanisms of early eye development provides insight into the molecular and cellular basis of developmental ocular anomalies, such as optic cup coloboma. Lastly, modeling human development and inherited retinal diseases using stem cell-derived retinal organoids generates opportunities to discover novel therapies for retinal diseases.
Collapse
Affiliation(s)
- Raven Diacou
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Prithviraj Nandigrami
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Andras Fiser
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Wei Liu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ruth Ashery-Padan
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Ales Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| |
Collapse
|
16
|
Todd L, Reh TA. Comparative Biology of Vertebrate Retinal Regeneration: Restoration of Vision through Cellular Reprogramming. Cold Spring Harb Perspect Biol 2022; 14:a040816. [PMID: 34580118 PMCID: PMC9248829 DOI: 10.1101/cshperspect.a040816] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The regenerative capacity of the vertebrate retina varies substantially across species. Whereas fish and amphibians can regenerate functional retina, mammals do not. In this perspective piece, we outline the various strategies nonmammalian vertebrates use to achieve functional regeneration of vision. We review key differences underlying the regenerative potential across species including the cellular source of postnatal progenitors, the diversity of cell fates regenerated, and the level of functional vision that can be achieved. Finally, we provide an outlook on the field of engineering the mammalian retina to replace neurons lost to injury or disease.
Collapse
Affiliation(s)
- Levi Todd
- Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA
| | - Thomas A Reh
- Department of Biological Structure, University of Washington, Seattle, Washington 98195, USA
| |
Collapse
|
17
|
Neveu MM, Padhy SK, Ramamurthy S, Takkar B, Jalali S, CP D, Padhi TR, Robson AG. Ophthalmological Manifestations of Oculocutaneous and Ocular Albinism: Current Perspectives. Clin Ophthalmol 2022; 16:1569-1587. [PMID: 35637898 PMCID: PMC9148211 DOI: 10.2147/opth.s329282] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 04/14/2022] [Indexed: 11/23/2022] Open
Abstract
Albinism describes a heterogeneous group of genetically determined disorders characterized by disrupted synthesis of melanin and a range of developmental ocular abnormalities. The main ocular features common to both oculocutaneous albinism (OCA), and ocular albinism (OA) include reduced visual acuity, refractive errors, foveal hypoplasia, congenital nystagmus, iris and fundus hypopigmentation and visual pathway misrouting, but clinical signs vary and there is phenotypic overlap with other pathologies. This study reviews the prevalence, genetics and ocular manifestations of OCA and OA, including abnormal development of the optic chiasm. The role of visual electrophysiology in the detection of chiasmal dysfunction and visual pathway misrouting is emphasized, highlighting how age-associated changes in visual evoked potential (VEP) test results must be considered to enable accurate diagnosis, and illustrated further by the inclusion of novel VEP data in genetically confirmed cases. Differential diagnosis is considered in the context of suspected retinal and other disorders, including rare syndromes that may masquerade as albinism.
Collapse
Affiliation(s)
- Magella M Neveu
- Department Electrophysiology, Moorfields Eye Hospital, London, EC1V 2PD, UK
- Institute of Ophthalmology, University College London, London, UK
| | | | | | - Brijesh Takkar
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Hyderabad, India
| | - Subhadra Jalali
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Hyderabad, India
| | - Deepika CP
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Hyderabad, India
| | - Tapas Ranjan Padhi
- Anant Bajaj Retina Institute, LV Prasad Eye Institute, Bhubaneswar, India
| | - Anthony G Robson
- Department Electrophysiology, Moorfields Eye Hospital, London, EC1V 2PD, UK
- Institute of Ophthalmology, University College London, London, UK
| |
Collapse
|
18
|
Yamaguchi N, Knaut H. Focal adhesion-mediated cell anchoring and migration: from in vitro to in vivo. Development 2022; 149:dev200647. [PMID: 35587444 PMCID: PMC9188754 DOI: 10.1242/dev.200647] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cell-extracellular matrix interactions have been studied extensively using cells cultured in vitro. These studies indicate that focal adhesion (FA)-based cell-extracellular matrix interactions are essential for cell anchoring and cell migration. Whether FAs play a similarly important role in vivo is less clear. Here, we summarize the formation and function of FAs in cultured cells and review how FAs transmit and sense force in vitro. Using examples from animal studies, we also describe the role of FAs in cell anchoring during morphogenetic movements and cell migration in vivo. Finally, we conclude by discussing similarities and differences in how FAs function in vitro and in vivo.
Collapse
Affiliation(s)
| | - Holger Knaut
- Skirball Institute of Biomolecular Medicine, New York University Grossman School of Medicine, New York, NY 10016, USA
| |
Collapse
|
19
|
Nandamuri SP, Lusk S, Kwan KM. Loss of zebrafish dzip1 results in inappropriate recruitment of periocular mesenchyme to the optic fissure and ocular coloboma. PLoS One 2022; 17:e0265327. [PMID: 35286359 PMCID: PMC8920261 DOI: 10.1371/journal.pone.0265327] [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] [Received: 12/15/2021] [Accepted: 02/28/2022] [Indexed: 01/13/2023] Open
Abstract
Cilia are essential for the development and function of many different tissues. Although cilia machinery is crucial in the eye for photoreceptor development and function, a role for cilia in early eye development and morphogenesis is still somewhat unclear: many zebrafish cilia mutants retain cilia at early stages due to maternal deposition of cilia components. An eye phenotype has been described in the mouse Arl13 mutant, however, zebrafish arl13b is maternally deposited, and an early role for cilia proteins has not been tested in zebrafish eye development. Here we use the zebrafish dzip1 mutant, which exhibits a loss of cilia throughout stages of early eye development, to examine eye development and morphogenesis. We find that in dzip1 mutants, initial formation of the optic cup proceeds normally, however, the optic fissure subsequently fails to close and embryos develop the structural eye malformation ocular coloboma. Further, neural crest cells, which are implicated in optic fissure closure, do not populate the optic fissure correctly, suggesting that their inappropriate localization may be the underlying cause of coloboma. Overall, our results indicate a role for dzip1 in proper neural crest localization in the optic fissure and optic fissure closure.
Collapse
Affiliation(s)
- Sri Pratima Nandamuri
- Department of Human Genetics, University of Utah, Salt Lake City, UT, United States of America
| | - Sarah Lusk
- Department of Human Genetics, University of Utah, Salt Lake City, UT, United States of America
| | - Kristen M. Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT, United States of America
| |
Collapse
|
20
|
Casey MA, Hill JT, Hoshijima K, Bryan CD, Gribble SL, Brown JT, Chien CB, Yost HJ, Kwan KM. Shutdown corner, a large deletion mutant isolated from a haploid mutagenesis screen in zebrafish. G3 (BETHESDA, MD.) 2022; 12:jkab442. [PMID: 35079792 PMCID: PMC9210284 DOI: 10.1093/g3journal/jkab442] [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] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022]
Abstract
Morphogenesis, the formation of three-dimensional organ structures, requires precise coupling of genetic regulation and complex cell behaviors. The genetic networks governing many morphogenetic systems, including that of the embryonic eye, are poorly understood. In zebrafish, several forward genetic screens have sought to identify factors regulating eye development. These screens often look for eye defects at stages after the optic cup is formed and when retinal neurogenesis is under way. This approach can make it difficult to identify mutants specific for morphogenesis, as opposed to neurogenesis. To this end, we carried out a forward genetic, small-scale haploid mutagenesis screen in zebrafish (Danio rerio) to identify factors that govern optic cup morphogenesis. We screened ∼100 genomes and isolated shutdown corner (sco), a mutant that exhibits multiple tissue defects and harbors a ∼10-Mb deletion that encompasses 89 annotated genes. Using a combination of live imaging and antibody staining, we found cell proliferation, cell death, and tissue patterning defects in the sco optic cup. We also observed other phenotypes, including paralysis, neuromuscular defects, and ocular vasculature defects. To date, the largest deletion mutants reported in zebrafish are engineered using CRISPR-Cas9 and are less than 300 kb. Because of the number of genes within the deletion interval, shutdown corner [Df(Chr05:sco)z207] could be a useful resource to the zebrafish community, as it may be helpful for gene mapping, understanding genetic interactions, or studying many genes lost in the mutant.
Collapse
Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Jonathon T Hill
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT 84602, USA
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Chase D Bryan
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32611, USA
| | - Suzanna L Gribble
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - J Thomas Brown
- Department of Biomedical Informatics, Vanderbilt University, Nashville, TN 37203, USA
| | - Chi-Bin Chien
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - H Joseph Yost
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| |
Collapse
|
21
|
Salbaum KA, Shelton ER, Serwane F. Retina organoids: Window into the biophysics of neuronal systems. BIOPHYSICS REVIEWS 2022; 3:011302. [PMID: 38505227 PMCID: PMC10903499 DOI: 10.1063/5.0077014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/16/2021] [Indexed: 03/21/2024]
Abstract
With a kind of magnetism, the human retina draws the eye of neuroscientist and physicist alike. It is attractive as a self-organizing system, which forms as a part of the central nervous system via biochemical and mechanical cues. The retina is also intriguing as an electro-optical device, converting photons into voltages to perform on-the-fly filtering before the signals are sent to our brain. Here, we consider how the advent of stem cell derived in vitro analogs of the retina, termed retina organoids, opens up an exploration of the interplay between optics, electrics, and mechanics in a complex neuronal network, all in a Petri dish. This review presents state-of-the-art retina organoid protocols by emphasizing links to the biochemical and mechanical signals of in vivo retinogenesis. Electrophysiological recording of active signal processing becomes possible as retina organoids generate light sensitive and synaptically connected photoreceptors. Experimental biophysical tools provide data to steer the development of mathematical models operating at different levels of coarse-graining. In concert, they provide a means to study how mechanical factors guide retina self-assembly. In turn, this understanding informs the engineering of mechanical signals required to tailor the growth of neuronal network morphology. Tackling the complex developmental and computational processes in the retina requires an interdisciplinary endeavor combining experiment and theory, physics, and biology. The reward is enticing: in the next few years, retina organoids could offer a glimpse inside the machinery of simultaneous cellular self-assembly and signal processing, all in an in vitro setting.
Collapse
Affiliation(s)
| | - Elijah R. Shelton
- Faculty of Physics and Center for NanoScience, Ludwig-Maximilians-Universität München, Munich, Germany
| | | |
Collapse
|
22
|
Lusk S, Kwan KM. Pax2a, but not pax2b, influences cell survival and periocular mesenchyme localization to facilitate zebrafish optic fissure closure. Dev Dyn 2021; 251:625-644. [PMID: 34535934 PMCID: PMC8930785 DOI: 10.1002/dvdy.422] [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: 07/01/2021] [Revised: 08/23/2021] [Accepted: 09/13/2021] [Indexed: 11/09/2022] Open
Abstract
Background Pax2 is required for optic fissure development in many organisms, including humans and zebrafish. Zebrafish loss‐of‐function mutations in pax2a display coloboma, yet the etiology of the morphogenetic defects is unclear. Further, pax2 is duplicated in zebrafish, and a role for pax2b in optic fissure development has not been examined. Results Using a combination of imaging and molecular genetics, we interrogated a potential role for pax2b and examined how loss of pax2 affects optic fissure development. Although optic fissure formation appears normal in pax2 mutants, an endothelial‐specific subset of periocular mesenchyme (POM) fails to initially localize within the optic fissure, yet both neural crest and endothelial‐derived POM ectopically accumulate at later stages in pax2a and pax2a; pax2b mutants. Apoptosis is not up‐regulated within the optic fissure in pax2 mutants, yet cell death is increased in tissues outside of the optic fissure, and when apoptosis is inhibited, coloboma is partially rescued. In contrast to pax2a, loss of pax2b does not appear to affect optic fissure morphogenesis. Conclusions Our results suggest that pax2a, but not pax2b, supports cell survival outside of the optic fissure and POM abundance within it to facilitate optic fissure closure.
Zebrafish pax2a null mutants display a defect in optic fissure closure and coloboma Loss of pax2b does not affect optic fissure development An endothelial‐specific subset of periocular mesenchyme cells fails to initially localize to the optic fissure in pax2a mutants At a later stage of optic fissure development both neural crest and endothelial‐derived periocular mesenchyme ectopically accumulate within the optic fissure Pax2a mutants have increased apoptosis in surrounding tissues, but not within the optic fissure margin cells, and apoptosis in part underlies the coloboma phenotype
Collapse
Affiliation(s)
- Sarah Lusk
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA
| |
Collapse
|
23
|
Zilova L, Weinhardt V, Tavhelidse T, Schlagheck C, Thumberger T, Wittbrodt J. Fish primary embryonic pluripotent cells assemble into retinal tissue mirroring in vivo early eye development. eLife 2021; 10:e66998. [PMID: 34252023 PMCID: PMC8275126 DOI: 10.7554/elife.66998] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/24/2021] [Indexed: 12/14/2022] Open
Abstract
Organoids derived from pluripotent stem cells promise the solution to current challenges in basic and biomedical research. Mammalian organoids are however limited by long developmental time, variable success, and lack of direct comparison to an in vivo reference. To overcome these limitations and address species-specific cellular organization, we derived organoids from rapidly developing teleosts. We demonstrate how primary embryonic pluripotent cells from medaka and zebrafish efficiently assemble into anterior neural structures, particularly retina. Within 4 days, blastula-stage cell aggregates reproducibly execute key steps of eye development: retinal specification, morphogenesis, and differentiation. The number of aggregated cells and genetic factors crucially impacted upon the concomitant morphological changes that were intriguingly reflecting the in vivo situation. High efficiency and rapid development of fish-derived organoids in combination with advanced genome editing techniques immediately allow addressing aspects of development and disease, and systematic probing of impact of the physical environment on morphogenesis and differentiation.
Collapse
Affiliation(s)
- Lucie Zilova
- Centre for Organismal Studies Heidelberg, Heidelberg UniversityHeidelbergGermany
| | - Venera Weinhardt
- Centre for Organismal Studies Heidelberg, Heidelberg UniversityHeidelbergGermany
| | - Tinatini Tavhelidse
- Centre for Organismal Studies Heidelberg, Heidelberg UniversityHeidelbergGermany
| | - Christina Schlagheck
- Centre for Organismal Studies Heidelberg, Heidelberg UniversityHeidelbergGermany
- Heidelberg International Biosciences Graduate School HBIGS and HeiKa Graduate School on “Functional Materials”HeidelbergGermany
| | - Thomas Thumberger
- Centre for Organismal Studies Heidelberg, Heidelberg UniversityHeidelbergGermany
| | - Joachim Wittbrodt
- Centre for Organismal Studies Heidelberg, Heidelberg UniversityHeidelbergGermany
| |
Collapse
|