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Sassine AG, Cakir Y, Della Vecchia L, Ehlers JP. Erdafitinib-associated retinal alterations and rapid onset bilateral white cataracts. Am J Ophthalmol Case Rep 2024; 34:102028. [PMID: 38572298 PMCID: PMC10987836 DOI: 10.1016/j.ajoc.2024.102028] [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: 02/02/2023] [Revised: 12/27/2023] [Accepted: 02/16/2024] [Indexed: 04/05/2024] Open
Abstract
Purpose This report aims to highlight the wide spectrum of ophthalmic adverse events associated with erdafitinib, a fibroblast growth factor inhibitor that blocks activation of the mitogen-activated protein kinase kinase (MAPK/MEK) cascade. The purpose of this report is to describe a case of erdafitinib-associated bilateral outer retinal alterations in the MEK-associated retinopathy spectrum and rapid onset bilateral total cataracts following a 20-month course of erdafitinib therapy. Observations A 69 year old male with metastatic bladder cancer presented 47 days following treatment initiation with daily erdafitinib (8-mg) with mild new subretinal fluid and minimal associated subretinal debris in the left eye and accentuation/thickening of the interdigitation zone in the right eye. Over the course of treatment, improvements were noted, particularly with erdafitinib dose reduction. At 20 months, both eyes developed rapidly progressive mature cataracts with significant visual changes, necessitating bilateral cataract extraction. Conclusions and importance The potential stability of moderate outer retinal changes (i.e., ellipsoid zone/interdigitation zone, subretinal fluid) while continuing erdafitinib therapy is highlighted in this report. In addition, the importance of continued ophthalmic surveillance is emphasized given the possible association of anterior segment adverse events with long-term erdafitinib use.
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Affiliation(s)
- Antoine G. Sassine
- The Tony and Leona Campane Center for Excellence in Image-Guided Surgery and Advanced Imaging Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH, 44195, USA
| | - Yavuz Cakir
- The Tony and Leona Campane Center for Excellence in Image-Guided Surgery and Advanced Imaging Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH, 44195, USA
| | - Lyndsey Della Vecchia
- The Tony and Leona Campane Center for Excellence in Image-Guided Surgery and Advanced Imaging Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH, 44195, USA
| | - Justis P. Ehlers
- The Tony and Leona Campane Center for Excellence in Image-Guided Surgery and Advanced Imaging Research, Cole Eye Institute, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH, 44195, USA
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2
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Camerino M, Chang W, Cvekl A. Analysis of long-range chromatin contacts, compartments and looping between mouse embryonic stem cells, lens epithelium and lens fibers. Epigenetics Chromatin 2024; 17:10. [PMID: 38643244 PMCID: PMC11031936 DOI: 10.1186/s13072-024-00533-x] [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: 11/15/2023] [Accepted: 03/08/2024] [Indexed: 04/22/2024] Open
Abstract
BACKGROUND Nuclear organization of interphase chromosomes involves individual chromosome territories, "open" and "closed" chromatin compartments, topologically associated domains (TADs) and chromatin loops. The DNA- and RNA-binding transcription factor CTCF together with the cohesin complex serve as major organizers of chromatin architecture. Cellular differentiation is driven by temporally and spatially coordinated gene expression that requires chromatin changes of individual loci of various complexities. Lens differentiation represents an advantageous system to probe transcriptional mechanisms underlying tissue-specific gene expression including high transcriptional outputs of individual crystallin genes until the mature lens fiber cells degrade their nuclei. RESULTS Chromatin organization between mouse embryonic stem (ES) cells, newborn (P0.5) lens epithelium and fiber cells were analyzed using Hi-C. Localization of CTCF in both lens chromatins was determined by ChIP-seq and compared with ES cells. Quantitative analyses show major differences between number and size of TADs and chromatin loop size between these three cell types. In depth analyses show similarities between lens samples exemplified by overlaps between compartments A and B. Lens epithelium-specific CTCF peaks are found in mostly methylated genomic regions while lens fiber-specific and shared peaks occur mostly within unmethylated DNA regions. Major differences in TADs and loops are illustrated at the ~ 500 kb Pax6 locus, encoding the critical lens regulatory transcription factor and within a larger ~ 15 Mb WAGR locus, containing Pax6 and other loci linked to human congenital diseases. Lens and ES cell Hi-C data (TADs and loops) together with ATAC-seq, CTCF, H3K27ac, H3K27me3 and ENCODE cis-regulatory sites are shown in detail for the Pax6, Sox1 and Hif1a loci, multiple crystallin genes and other important loci required for lens morphogenesis. The majority of crystallin loci are marked by unexpectedly high CTCF-binding across their transcribed regions. CONCLUSIONS Our study has generated the first data on 3-dimensional (3D) nuclear organization in lens epithelium and lens fibers and directly compared these data with ES cells. These findings generate novel insights into lens-specific transcriptional gene control, open new research avenues to study transcriptional condensates in lens fiber cells, and enable studies of non-coding genetic variants linked to cataract and other lens and ocular abnormalities.
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Affiliation(s)
- Michael Camerino
- The Departments Genetics, Albert Einstein College of Medicine, NY10461, Bronx, USA
| | - William Chang
- Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, NY10461, Bronx, USA
| | - Ales Cvekl
- The Departments Genetics, Albert Einstein College of Medicine, NY10461, Bronx, USA.
- Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, NY10461, Bronx, USA.
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3
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Perez RC, Yang X, Familari M, Martinez G, Lovicu FJ, Hime GR, de Iongh RU. TOB1 and TOB2 mark distinct RNA processing granules in differentiating lens fiber cells. J Mol Histol 2024; 55:121-138. [PMID: 38165569 DOI: 10.1007/s10735-023-10177-y] [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: 07/18/2023] [Accepted: 11/12/2023] [Indexed: 01/04/2024]
Abstract
Differentiation of lens fiber cells involves a complex interplay of signals from growth factors together with tightly regulated gene expression via transcriptional and post-transcriptional regulators. Various studies have demonstrated that RNA-binding proteins, functioning in ribonucleoprotein granules, have important roles in regulating post-transcriptional expression during lens development. In this study, we examined the expression and localization of two members of the BTG/TOB family of RNA-binding proteins, TOB1 and TOB2, in the developing lens and examined the phenotype of mice that lack Tob1. By RT-PCR, both Tob1 and Tob2 mRNA were detected in epithelial and fiber cells of embryonic and postnatal murine lenses. In situ hybridization showed Tob1 and Tob2 mRNA were most intensely expressed in the early differentiating fibers, with weaker expression in anterior epithelial cells, and both appeared to be downregulated in the germinative zone of E15.5 lenses. TOB1 protein was detected from E11.5 to E16.5 and was predominantly detected in large cytoplasmic puncta in early differentiating fiber cells, often co-localizing with the P-body marker, DCP2. Occasional nuclear puncta were also observed. By contrast, TOB2 was detected in a series of interconnected peri-nuclear granules, in later differentiating fiber cells of the inner cortex. TOB2 did not appear to co-localize with DCP2 but did partially co-localize with an early stress granule marker (EIF3B). These data suggest that TOB1 and TOB2 are involved with different aspects of the mRNA processing cycle in lens fiber cells. In vitro experiments using rat lens epithelial explants treated with or without a fiber differentiating dose of FGF2 showed that both TOB1 and TOB2 were up-regulated during FGF-induced differentiation. In differentiating explants, TOB1 also co-localized with DCP2 in large cytoplasmic granules. Analyses of Tob1-/- mice revealed relatively normal lens morphology but a subtle defect in cell cycle arrest of some cells at the equator and in the lens fiber mass of E13.5 embryos. Overall, these findings suggest that TOB proteins play distinct regulatory roles in RNA processing during lens fiber differentiation.
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Affiliation(s)
- Rafaela C Perez
- Ocular Development Laboratory, Anatomy & Physiology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Xenia Yang
- Ocular Development Laboratory, Anatomy & Physiology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Mary Familari
- School of Biosciences, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Gemma Martinez
- Ocular Development Laboratory, Anatomy & Physiology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Frank J Lovicu
- Molecular and Cellular Biomedicine, School of Medical Sciences and Save Sight Institute, University of Sydney, Sydney, NSW, 2006, Australia
| | - Gary R Hime
- Stem Cell Genetics Laboratory, Anatomy & Physiology, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Robb U de Iongh
- Ocular Development Laboratory, Anatomy & Physiology, University of Melbourne, Parkville, VIC, 3010, Australia.
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Brennan L, Disatham J, Menko AS, Kantorow M. Multiomic analysis implicates FOXO4 in genetic regulation of chick lens fiber cell differentiation. Dev Biol 2023; 504:25-37. [PMID: 37722500 PMCID: PMC10843493 DOI: 10.1016/j.ydbio.2023.09.005] [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: 05/15/2023] [Revised: 09/06/2023] [Accepted: 09/14/2023] [Indexed: 09/20/2023]
Abstract
A classic model for identification of novel differentiation mechanisms and pathways is the eye lens that consists of a monolayer of quiescent epithelial cells that are the progenitors of a core of mature fully differentiated fiber cells. The differentiation of lens epithelial cells into fiber cells follows a coordinated program involving cell cycle exit, expression of key structural proteins and the hallmark elimination of organelles to achieve transparency. Although multiple mechanisms and pathways have been identified to play key roles in lens differentiation, the entirety of mechanisms governing lens differentiation remain to be discovered. A previous study established that specific chromatin accessibility changes were directly associated with the expression of essential lens fiber cell genes, suggesting that the activity of transcription factors needed for expression of these genes could be regulated through binding access to the identified chromatin regions. Sequence analysis of the identified chromatin accessible regions revealed enhanced representation of the binding sequence for the transcription factor FOXO4 suggesting a direct role for FOXO4 in expression of these genes. FOXO4 is known to regulate a variety of cellular processes including cellular response to metabolic and oxidative stress, cell cycle withdrawal, and homeostasis, suggesting a previously unidentified role for FOXO4 in the regulation of lens cell differentiation. To further evaluate the role of FOXO4 we employed a multiomics approach to analyze the relationship between genome-wide FOXO4 binding, the differentiation-specific expression of key genes, and chromatin accessibility. To better identify active promoters and enhancers we also examined histone modification through analysis of H3K27ac. Specific methods included CUT&RUN (FOXO4 binding and H3K27ac modification), RNA-seq (differentiation state specific gene expression), and ATAC-seq (chromatin accessibility). CUT&RUN identified 20,966 FOXO4 binding sites and 33,921 H3K27ac marked regions across the lens fiber cell genome. RNA-seq identified 956 genes with significantly greater expression levels in fiber cells compared to epithelial cells (log2FC > 0.7, q < 0.05) and 2548 genes with significantly lower expression levels (log2FC < -0.7, q < 0.05). Integrated analysis identified 1727 differentiation-state specific genes that were nearest neighbors to at least one FOXO4 binding site, including genes encoding lens gap junctions (GJA1, GJA3), lens structural proteins (BFSP1, CRYBB1, ASL1), and genes required for lens transparency (HSF4, NRCAM). Multiomics analysis comparing the identified FOXO4 binding sites in published ATAC-seq data revealed that chromatin accessibility was associated with FOXO4-dependent gene expression during lens differentiation. The results provide evidence for an important requirement for FOXO4 in the regulated expression of key genes required for lens differentiation and link epigenetic regulation of chromatin accessibility and H3K27ac histone modification with the function of FOXO4 in controlling lens gene expression during lens fiber cell differentiation.
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Affiliation(s)
- Lisa Brennan
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Joshua Disatham
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - A Sue Menko
- Department of Pathology and Genomic Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Marc Kantorow
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
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5
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Giannone AA, Sellitto C, Rosati B, McKinnon D, White TW. Single-Cell RNA Sequencing Analysis of the Early Postnatal Mouse Lens Epithelium. Invest Ophthalmol Vis Sci 2023; 64:37. [PMID: 37870847 PMCID: PMC10599162 DOI: 10.1167/iovs.64.13.37] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 10/06/2023] [Indexed: 10/24/2023] Open
Abstract
Purpose The lens epithelium maintains the overall health of the organ. We used single-cell RNA sequencing (scRNA-seq) technology to assess transcriptional heterogeneity between cells in the postnatal day 2 (P2) epithelium and identify distinct epithelial cell subtypes. Analysis of these data was used to better understand lens growth, differentiation, and homeostasis on P2. Methods scRNA-seq on P2 mouse lenses was performed using the 10x Genomics Chromium Single Cell 3' Kit (v3.1) and short-read Illumina sequencing. Sequence alignment and preprocessing of data were conducted using 10x Genomics Cell Ranger software. Seurat was employed for preprocessing, quality control, dimensionality reduction, and cell clustering, and Monocle was utilized for trajectory analysis to understand the developmental progression of the lens cells. CellChat and GO analyses were used to explore cell-cell communication networks and signaling interactions. Results Lens epithelial cells (LECs) were divided into seven subclusters, classified by specific gene markers. The expression of crystallin, cell-cycle, and metabolic genes was not uniform, indicating distinct functional roles of LECs. Trajectory analysis predicted a bifurcation of differentiating and cycling cells from an Igfbp5+ progenitor pool. We also identified heterogeneity in signaling molecules and pathways, suggesting that cycling and progenitor subclusters have prominent roles in coordinating crosstalk. Conclusions scRNA-seq corroborated many known markers of epithelial differentiation and proliferation while providing further insight into the pathways and genes directing these processes. Interestingly, we demonstrated that the developing epithelium can be divided into distinct subpopulations. These clusters reflect the transcriptionally diverse roles of the epithelium in proliferation, signaling, and maintenance.
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Affiliation(s)
- Adrienne A. Giannone
- Department of Physiology and Biophysics, Stony Brook University School of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Caterina Sellitto
- Department of Physiology and Biophysics, Stony Brook University School of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Barbara Rosati
- Department of Physiology and Biophysics, Stony Brook University School of Medicine, Stony Brook University, Stony Brook, New York, United States
- Veterans Affairs Medical Center, Northport, New York, United States
| | - David McKinnon
- Department of Neurobiology and Behavior, Stony Brook University School of Medicine, Stony Brook University, Stony Brook, New York, United States
| | - Thomas W. White
- Department of Physiology and Biophysics, Stony Brook University School of Medicine, Stony Brook University, Stony Brook, New York, United States
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6
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Li X, Luo LL, Li RF, Chen CL, Sun M, Lin S. Pantothenate Kinase 4 Governs Lens Epithelial Fibrosis by Negatively Regulating Pyruvate Kinase M2-Related Glycolysis. Aging Dis 2023; 14:1834-1852. [PMID: 37196116 PMCID: PMC10529755 DOI: 10.14336/ad.2023.0216-1] [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: 01/02/2023] [Accepted: 02/16/2023] [Indexed: 05/19/2023] Open
Abstract
Lens fibrosis is one of the leading causes of cataract in the elderly population. The primary energy substrate of the lens is glucose from the aqueous humor, and the transparency of mature lens epithelial cells (LECs) is dependent on glycolysis for ATP. Therefore, the deconstruction of reprogramming of glycolytic metabolism can contribute to further understanding of LEC epithelial-mesenchymal transition (EMT). In the present study, we found a novel pantothenate kinase 4 (PANK4)-related glycolytic mechanism that regulates LEC EMT. The PANK4 level was correlated with aging in cataract patients and mice. Loss of function of PANK4 significantly contributed to alleviating LEC EMT by upregulating pyruvate kinase M2 isozyme (PKM2), which was phosphorylated at Y105, thus switching oxidative phosphorylation to glycolysis. However, PKM2 regulation did not affect PANK4, demonstrating the downstream role of PKM2. Inhibition of PKM2 in Pank4-/- mice caused lens fibrosis, which supports the finding that the PANK4-PKM2 axis is required for LEC EMT. Glycolytic metabolism-governed hypoxia inducible factor (HIF) signaling is involved in PANK4-PKM2-related downstream signaling. However, HIF-1α elevation was independent of PKM2 (S37) but PKM2 (Y105) when PANK4 was deleted, which demonstrated that PKM2 and HIF-1α were not involved in a classic positive feedback loop. Collectively, these results indicate a PANK4-related glycolysis switch that may contribute to HIF-1 stabilization and PKM2 phosphorylation at Y105 and inhibit LEC EMT. The mechanism elucidation in our study may also shed light on fibrosis treatments for other organs.
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Affiliation(s)
- Xue Li
- Department of Ophthalmology, Daping Hospital, Army Medical Center of PLA, Army Medical University, Chongqing, China.
| | - Lin-Lin Luo
- Department of Ophthalmology, Daping Hospital, Army Medical Center of PLA, Army Medical University, Chongqing, China.
| | - Rui-Feng Li
- Department of Ophthalmology, Daping Hospital, Army Medical Center of PLA, Army Medical University, Chongqing, China.
| | - Chun-Lin Chen
- Department of Ophthalmology, Daping Hospital, Army Medical Center of PLA, Army Medical University, Chongqing, China.
| | - Min Sun
- Department of Ophthalmology, Daping Hospital, Army Medical Center of PLA, Army Medical University, Chongqing, China.
| | - Sen Lin
- Department of Neurology, Xinqiao Hospital, The Second Affiliated Hospital, Army Medical University, Chongqing, China.
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7
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Disatham J, Brennan L, Cvekl A, Kantorow M. Multiomics Analysis Reveals Novel Genetic Determinants for Lens Differentiation, Structure, and Transparency. Biomolecules 2023; 13:693. [PMID: 37189439 PMCID: PMC10136076 DOI: 10.3390/biom13040693] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 04/13/2023] [Accepted: 04/16/2023] [Indexed: 05/17/2023] Open
Abstract
Recent advances in next-generation sequencing and data analysis have provided new gateways for identification of novel genome-wide genetic determinants governing tissue development and disease. These advances have revolutionized our understanding of cellular differentiation, homeostasis, and specialized function in multiple tissues. Bioinformatic and functional analysis of these genetic determinants and the pathways they regulate have provided a novel basis for the design of functional experiments to answer a wide range of long-sought biological questions. A well-characterized model for the application of these emerging technologies is the development and differentiation of the ocular lens and how individual pathways regulate lens morphogenesis, gene expression, transparency, and refraction. Recent applications of next-generation sequencing analysis on well-characterized chicken and mouse lens differentiation models using a variety of omics techniques including RNA-seq, ATAC-seq, whole-genome bisulfite sequencing (WGBS), chip-seq, and CUT&RUN have revealed a wide range of essential biological pathways and chromatin features governing lens structure and function. Multiomics integration of these data has established new gene functions and cellular processes essential for lens formation, homeostasis, and transparency including the identification of novel transcription control pathways, autophagy remodeling pathways, and signal transduction pathways, among others. This review summarizes recent omics technologies applied to the lens, methods for integrating multiomics data, and how these recent technologies have advanced our understanding ocular biology and function. The approach and analysis are relevant to identifying the features and functional requirements of more complex tissues and disease states.
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Affiliation(s)
- Joshua Disatham
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA; (J.D.); (L.B.)
| | - Lisa Brennan
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA; (J.D.); (L.B.)
| | - Ales Cvekl
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA;
| | - Marc Kantorow
- Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL 33431, USA; (J.D.); (L.B.)
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8
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Regulation of lens water content: Effects on the physiological optics of the lens. Prog Retin Eye Res 2022:101152. [DOI: 10.1016/j.preteyeres.2022.101152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/21/2022] [Accepted: 11/22/2022] [Indexed: 12/09/2022]
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9
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Wang X, Hui Q, Jin Z, Rao F, Jin L, Yu B, Banda J, Li X. Roles of growth factors in eye development and ophthalmic diseases. Zhejiang Da Xue Xue Bao Yi Xue Ban 2022; 51:613-625. [PMID: 36581579 PMCID: PMC10264994 DOI: 10.3724/zdxbyxb-2022-0603] [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: 03/01/2022] [Accepted: 07/30/2022] [Indexed: 12/02/2022]
Abstract
Growth factors are active substances secreted by a variety of cells, which act as messengers to regulate cell migration, proliferation and differentiation. Many growth factors are involved in the eye development or the pathophysiological processes of eye diseases. Growth factors such as vascular endothelial growth factor and basic fibroblast growth factor mediate the occurrence and development of diabetic retinopathy, choroidal neovascularization, cataract, diabetic macular edema, and other retinal diseases. On the other hand, growth factors like nerve growth factor, ciliary neurotrophic factor, glial cell line-derived neurotrophic factor, pigment epithelial-derived factor and granulocyte colony-stimulating factor are known to promote optic nerve injury repair. Growth factors are also related to the pathogenesis of myopia. Fibroblast growth factor, transforming growth factor-β, and insulin-like growth factor regulate scleral thickness and influence the occurrence and development of myopia. This article reviews growth factors involved in ocular development and ocular pathophysiology, discusses the relationship between growth factors and ocular diseases, to provide reference for the application of growth factors in ophthalmology.
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Cvekl A, Camerino MJ. Generation of Lens Progenitor Cells and Lentoid Bodies from Pluripotent Stem Cells: Novel Tools for Human Lens Development and Ocular Disease Etiology. Cells 2022; 11:cells11213516. [PMID: 36359912 PMCID: PMC9658148 DOI: 10.3390/cells11213516] [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: 09/28/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
In vitro differentiation of human pluripotent stem cells (hPSCs) into specialized tissues and organs represents a powerful approach to gain insight into those cellular and molecular mechanisms regulating human development. Although normal embryonic eye development is a complex process, generation of ocular organoids and specific ocular tissues from pluripotent stem cells has provided invaluable insights into the formation of lineage-committed progenitor cell populations, signal transduction pathways, and self-organization principles. This review provides a comprehensive summary of recent advances in generation of adenohypophyseal, olfactory, and lens placodes, lens progenitor cells and three-dimensional (3D) primitive lenses, "lentoid bodies", and "micro-lenses". These cells are produced alone or "community-grown" with other ocular tissues. Lentoid bodies/micro-lenses generated from human patients carrying mutations in crystallin genes demonstrate proof-of-principle that these cells are suitable for mechanistic studies of cataractogenesis. Taken together, current and emerging advanced in vitro differentiation methods pave the road to understand molecular mechanisms of cataract formation caused by the entire spectrum of mutations in DNA-binding regulatory genes, such as PAX6, SOX2, FOXE3, MAF, PITX3, and HSF4, individual crystallins, and other genes such as BFSP1, BFSP2, EPHA2, GJA3, GJA8, LIM2, MIP, and TDRD7 represented in human cataract patients.
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Affiliation(s)
- Aleš Cvekl
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Correspondence: ; Tel.: +1-718-430-3217; Fax: +1-718-430-8778
| | - Michael John Camerino
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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11
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Muacevic A, Adler JR. The Prevalence of Cataract in Children. Cureus 2022; 14:e30135. [PMID: 36381901 PMCID: PMC9645413 DOI: 10.7759/cureus.30135] [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: 08/09/2022] [Accepted: 10/10/2022] [Indexed: 11/24/2022] Open
Abstract
Cataract is the leading cause of childhood blindness in developing countries. Early detection and treatment of childhood cataracts can reduce the burden of blindness in the nation. Often the etiology of pediatric cataract is idiopathic; however, genetics play a role in the development of congenital cataract. According to epidemiologists, one-fourth of cases of congenital cataracts are hereditary. Gene responsible for the development of cataract is identified using gene mapping, which helps to prevent future blindness in the family. Cataracts can also present with systemic disease, microphthalmia, microcornea, and aniridia. The presentation of cataracts varies in individuals, some are symptomatic while others are asymptomatic. Parents after noticing strabismus and leukocoria bring their children to an ophthalmologist. Early diagnosis can restore visual function in cases of congenital cataract. In young babies, the type of cataract is determined using slit-lamp examination and examination under anesthesia in OR. Most cases of pediatric cataracts are accidental findings during routine checkups. On direct ophthalmoscopy, red reflex is not appreciated in cases of cataracts. Advancing technology changes the ophthalmologist's approach to pediatric cataract surgery, improving postoperative refractory function. In children, minor incision surgery was preferred to heal early. An appropriate choice of intraocular lens (IOL) should be made for implantation in a child's eye to avoid postimplanted complications. Inflammation and amblyopia affect the outcome of treatment. Complications of cataract surgery include posterior capsule opacification, glaucoma, inflammation, and uveitis.
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12
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Giannone AA, Li L, Sellitto C, White TW. Physiological Mechanisms Regulating Lens Transport. Front Physiol 2022; 12:818649. [PMID: 35002784 PMCID: PMC8735835 DOI: 10.3389/fphys.2021.818649] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 12/10/2021] [Indexed: 12/02/2022] Open
Abstract
The transparency and refractive properties of the lens are maintained by the cellular physiology provided by an internal microcirculation system that utilizes spatial differences in ion channels, transporters and gap junctions to establish standing electrochemical and hydrostatic pressure gradients that drive the transport of ions, water and nutrients through this avascular tissue. Aging has negative effects on lens transport, degrading ion and water homeostasis, and producing changes in lens water content. This alters the properties of the lens, causing changes in optical quality and accommodative amplitude that initially result in presbyopia in middle age and ultimately manifest as cataract in the elderly. Recent advances have highlighted that the lens hydrostatic pressure gradient responds to tension transmitted to the lens through the Zonules of Zinn through a mechanism utilizing mechanosensitive channels, multiple sodium transporters respond to changes in hydrostatic pressure to restore equilibrium, and that connexin hemichannels and diverse intracellular signaling cascades play a critical role in these responses. The mechanistic insight gained from these studies has advanced our understanding of lens transport and how it responds and adapts to different inputs both from within the lens, and from surrounding ocular structures.
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Affiliation(s)
- Adrienne A Giannone
- Master of Science Program, Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, United States
| | - Leping Li
- Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Caterina Sellitto
- Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, United States
| | - Thomas W White
- Department of Physiology and Biophysics, School of Medicine, Stony Brook University, Stony Brook, NY, United States
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13
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Chen M, Fu Y, Wang X, Wu R, Su D, Zhou N, Qi Y. Metformin protects lens epithelial cells against senescence in a naturally aged mouse model. Cell Death Dis 2022; 8:8. [PMID: 35013152 PMCID: PMC8748516 DOI: 10.1038/s41420-021-00800-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 11/11/2021] [Accepted: 12/13/2021] [Indexed: 11/21/2022]
Abstract
The senescence of lens epithelial cells (LECs) is a major factor leading to age-related cataract (ARC). ARC results in visual impairment and severe vision loss in elderly patients. However, the specific mechanism of ARC remains unclear, and there are no effective therapeutic agents to halt the formation of ARC. This study aimed to assess the underlying mechanism of the formation of ARC and investigate the potential anti-ageing effect of metformin (MET) on ARC. Male C57BL/6 mice were divided into three groups: the control group having young mice (3 months old, n = 40), the naturally aged group (aged 20 months, n = 60) and the MET group (MET, 20 months, n = 60). Mice in the control and the naturally aged groups were fed a standard purified mouse diet ad libitum and water, whereas those in the MET group were fed chows supplemented with 0.1% MET for 10 months. The transparency of the lens and age-associated proteins p21 and p53 were analysed in the LECs of these three groups. Furthermore, we determined the expressions of the adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathway and the effect of MET on this pathway in LECs during the ageing process of ARC. In addition, the relationship between autophagy and the senescence of LECs and the role of MET in the autophagy of LECs during the ageing process of ARC were examined. Our results indicated that age-related inactivation of the AMPK pathway and impairment of autophagy might contribute to the senescence of LECs and the occurrence of ARC. More importantly, these results demonstrated that MET effectively alleviated the senescence of LECs and the formation of ARC probably via inactivation of the AMPK pathway and augmentation of autophagy. These findings revealed that MET can be exploited as a potentially useful drug for ARC prevention. Our study will help in enlightening the development of innovative strategies for the clinical treatment of ARC.
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Affiliation(s)
- Mengmeng Chen
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, 150001, Harbin, China
| | - Yushan Fu
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, 150001, Harbin, China
| | - Xu Wang
- Department of Ophthalmology, Xixi Hospital of Hangzhou, 310023, Hangzhou, China
| | - Ruitong Wu
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, 150001, Harbin, China
| | - Dongmei Su
- Department of Genetics, National Research Institute for Family Planning, Health Department, 100000, Beijing, China
| | - Nan Zhou
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, 150001, Harbin, China.
| | - Yanhua Qi
- Department of Ophthalmology, The Second Affiliated Hospital of Harbin Medical University, 150001, Harbin, China.
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14
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Summers JA, Schaeffel F, Marcos S, Wu H, Tkatchenko AV. Functional integration of eye tissues and refractive eye development: Mechanisms and pathways. Exp Eye Res 2021; 209:108693. [PMID: 34228967 DOI: 10.1016/j.exer.2021.108693] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 06/28/2021] [Accepted: 06/30/2021] [Indexed: 12/16/2022]
Abstract
Refractive eye development is a tightly coordinated developmental process. The general layout of the eye and its various components are established during embryonic development, which involves a complex cross-tissue signaling. The eye then undergoes a refinement process during the postnatal emmetropization process, which relies heavily on the integration of environmental and genetic factors and is controlled by an elaborate genetic network. This genetic network encodes a multilayered signaling cascade, which converts visual stimuli into molecular signals that guide the postnatal growth of the eye. The signaling cascade underlying refractive eye development spans across all ocular tissues and comprises multiple signaling pathways. Notably, tissue-tissue interaction plays a key role in both embryonic eye development and postnatal eye emmetropization. Recent advances in eye biometry, physiological optics and systems genetics of refractive error have significantly advanced our understanding of the biological processes involved in refractive eye development and provided a framework for the development of new treatment options for myopia. In this review, we summarize the recent data on the mechanisms and signaling pathways underlying refractive eye development and discuss new evidence suggesting a wide-spread signal integration across different tissues and ocular components involved in visually guided eye growth.
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Affiliation(s)
- Jody A Summers
- Department of Cell Biology, University of Oklahoma Health Science Center, Oklahoma City, OK, USA
| | - Frank Schaeffel
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, Tuebingen, Germany; Myopia Research Group, Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
| | - Susana Marcos
- Instituto de Óptica "Daza de Valdés", Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
| | - Hao Wu
- Department of Ophthalmology, Columbia University, New York, USA
| | - Andrei V Tkatchenko
- Department of Ophthalmology, Columbia University, New York, USA; Department of Pathology and Cell Biology, Columbia University, New York, USA.
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15
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Muzzio N, Moya S, Romero G. Multifunctional Scaffolds and Synergistic Strategies in Tissue Engineering and Regenerative Medicine. Pharmaceutics 2021; 13:792. [PMID: 34073311 PMCID: PMC8230126 DOI: 10.3390/pharmaceutics13060792] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/17/2021] [Accepted: 05/20/2021] [Indexed: 12/20/2022] Open
Abstract
The increasing demand for organ replacements in a growing world with an aging population as well as the loss of tissues and organs due to congenital defects, trauma and diseases has resulted in rapidly evolving new approaches for tissue engineering and regenerative medicine (TERM). The extracellular matrix (ECM) is a crucial component in tissues and organs that surrounds and acts as a physical environment for cells. Thus, ECM has become a model guide for the design and fabrication of scaffolds and biomaterials in TERM. However, the fabrication of a tissue/organ replacement or its regeneration is a very complex process and often requires the combination of several strategies such as the development of scaffolds with multiple functionalities and the simultaneous delivery of growth factors, biochemical signals, cells, genes, immunomodulatory agents, and external stimuli. Although the development of multifunctional scaffolds and biomaterials is one of the most studied approaches for TERM, all these strategies can be combined among them to develop novel synergistic approaches for tissue regeneration. In this review we discuss recent advances in which multifunctional scaffolds alone or combined with other strategies have been employed for TERM purposes.
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Affiliation(s)
- Nicolas Muzzio
- Department of Biomedical Engineering and Chemical Engineering, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA;
| | - Sergio Moya
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA), Paseo Miramon 182 C, 20014 Donostia-San Sebastian, Spain;
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, 61-614 Poznan, Poland
| | - Gabriela Romero
- Department of Biomedical Engineering and Chemical Engineering, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA;
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16
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Cvekl A, Eliscovich C. Crystallin gene expression: Insights from studies of transcriptional bursting. Exp Eye Res 2021; 207:108564. [PMID: 33894228 DOI: 10.1016/j.exer.2021.108564] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 03/05/2021] [Accepted: 03/22/2021] [Indexed: 01/26/2023]
Abstract
Cellular differentiation is marked by temporally and spatially regulated gene expression. The ocular lens is one of the most powerful mammalian model system since it is composed from only two cell subtypes, called lens epithelial and fiber cells. Lens epithelial cells differentiate into fiber cells through a series of spatially and temporally orchestrated processes, including massive production of crystallins, cellular elongation and the coordinated degradation of nuclei and other organelles. Studies of transcriptional and posttranscriptional gene regulatory mechanisms in lens provide a wide range of opportunities to understand global molecular mechanisms of gene expression as steady-state levels of crystallin mRNAs reach very high levels comparable to globin genes in erythrocytes. Importantly, dysregulation of crystallin gene expression results in lens structural abnormalities and cataracts. The mRNA life cycle is comprised of multiple stages, including transcription, splicing, nuclear export into cytoplasm, stabilization, localization, translation and ultimate decay. In recent years, development of modern mRNA detection methods with single molecule and single cell resolution enabled transformative studies to visualize the mRNA life cycle to generate novel insights into the sequential regulatory mechanisms of gene expression during embryogenesis. This review is focused on recent major advancements in studies of transcriptional bursting in differentiating lens fiber cells, analysis of nascent mRNA expression from bi-directional promoters, transient nuclear accumulation of specific mRNAs, condensation of chromatin prior lens fiber cell denucleation, and outlines future studies to probe the interactions of individual mRNAs with specific RNA-binding proteins (RBPs) in the cytoplasm and regulation of translation and mRNA decay.
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Affiliation(s)
- Ales Cvekl
- Department of Ophthalmology and VIsual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| | - Carolina Eliscovich
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
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17
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Shparberg R, Dewi CU, Gnanasambandapillai V, Liyanage L, O'Connor MD. Single cell RNA-sequencing data generated from human pluripotent stem cell-derived lens epithelial cells. Data Brief 2021; 34:106657. [PMID: 33521174 PMCID: PMC7820909 DOI: 10.1016/j.dib.2020.106657] [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: 10/29/2020] [Revised: 12/09/2020] [Accepted: 12/10/2020] [Indexed: 11/10/2022] Open
Abstract
Detailed transcriptomic analyses of differentiated cell populations derived from human pluripotent stem cells is routinely used to assess the identity and utility of the differentiated cells. Here we provide single cell RNA-sequencing data obtained from ROR1-expressing lens epithelial cells (ROR1e LECs), obtained via directed differentiation of CA1 human embryonic stem cells. Analysis of the data using principal component analysis, heat maps and gene ontology assessments revealed phenotypes associated with lens epithelial cells. These data provide a resource for future characterisation of both normal and cataractous human lens biology. Corresponding morphological and functional data obtained from ROR1e LECs are reported in the associated research article "A simplified method for producing human lens epithelial cells and light-focusing micro-lenses from pluripotent stem cells " (Dewi et al., 2020).
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Affiliation(s)
- Rachel Shparberg
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Chitra Umala Dewi
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Vikkitharan Gnanasambandapillai
- Garvan-Weizmann Centre for Cellular Genomics, Garvan Institute, UNSW Cellular Genomics Futures Institute, University of New South Wales, Sydney 2010, Australia
| | - Liwan Liyanage
- School of Computer, Data and Mathematical Sciences, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Michael D. O'Connor
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia
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18
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Reversible corneal stromal thinning, acute-onset white cataract and angle-closure glaucoma due to erdafitinib, a fibroblast growth factor receptor inhibitor: Report of three cases. J Fr Ophtalmol 2020; 44:67-75. [PMID: 33162180 DOI: 10.1016/j.jfo.2020.03.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 11/22/2022]
Abstract
PURPOSE To report corneal and lens toxicity in patients undergoing chemotherapy with erdafitinib, a fibroblast growth factor receptor (FGFR) inhibitor. METHODS This retrospective case series contains three patients from a cohort of 41 patients receiving erdafitinib, a selective pan-FGFR inhibitor, for chemotherapy. These three patients underwent complete ophthalmic examination: one was followed by corneal topography and the other two were followed by anterior segment optical coherence tomography. RESULTS All three patients had severe dry eye syndrome. One patient had bilateral corneal thinning. One patient had bilateral neurosensory retinal detachment, unilateral corneal thinning and white cataracts in both eyes. The third patient had bilateral corneal thinning, a corneal ulcer of the left eye and acute-onset white cataracts in both eyes, causing angle-closure glaucoma in the left eye. Following the cessation of erdafitinib treatment or a decrease in the dose used, corneal thinning resolved in all three cases within four months. Acute-onset cataracts were treated urgently by surgery, with no complications. In one patient, although the corneal ulcer healed, corneal transparency was lost, and the patient never fully recovered his initial vision. CONCLUSION Bilateral neurosensory retinal detachment associated with FGFR inhibitor use has already been reported. However, we provide herein the first report of reversible corneal thinning and acute-onset white cataracts causing angle-closure glaucoma associated with FGFR inhibitor use. Early recognition and management of these adverse ocular reactions are required to prevent vision loss due to acute glaucoma and/or corneal ulcer.
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19
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Dewi CU, Mason M, Cohen-Hyams T, Killingsworth MC, Harman DG, Gnanasambandapillai V, Liyanage L, O'Connor MD. A simplified method for producing human lens epithelial cells and light-focusing micro-lenses from pluripotent stem cells. Exp Eye Res 2020; 202:108317. [PMID: 33130031 DOI: 10.1016/j.exer.2020.108317] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 10/05/2020] [Accepted: 10/14/2020] [Indexed: 11/26/2022]
Abstract
Here we describe a modified method for harvesting tens-of-millions of human lens epithelial-like cells from differentiated pluripotent stem cell cultures. To assess the utility of this method, we analysed the lens cell population via: light microscopy; single cell RNA-sequencing and gene ontology analyses; formation of light-focusing micro-lenses; mass spectrometry; and electron microscopy. Both individually and collectively, the data indicate this simplified harvesting method provides a large-scale source of stem cell-derived lens cells and micro-lenses for investigating human lens and cataract formation.
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Affiliation(s)
- Chitra Umala Dewi
- School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | - Michele Mason
- School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | - Tzipi Cohen-Hyams
- Electron Microscopy Laboratory, NSW Health Pathology and Correlative Microscopy Facility, Ingham Institute, Liverpool, NSW, 2170, Australia
| | - Murray C Killingsworth
- Electron Microscopy Laboratory, NSW Health Pathology and Correlative Microscopy Facility, Ingham Institute, Liverpool, NSW, 2170, Australia
| | - David G Harman
- School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | | | - Liwan Liyanage
- School of Computer, Data and Mathematical Sciences, Western Sydney University, Campbelltown, NSW, 2560, Australia
| | - Michael D O'Connor
- School of Medicine, Western Sydney University, Campbelltown, NSW, 2560, Australia.
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20
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Wormstone IM, Wormstone YM, Smith AJO, Eldred JA. Posterior capsule opacification: What's in the bag? Prog Retin Eye Res 2020; 82:100905. [PMID: 32977000 DOI: 10.1016/j.preteyeres.2020.100905] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/18/2020] [Accepted: 09/21/2020] [Indexed: 12/18/2022]
Abstract
Cataract, a clouding of the lens, is the most common cause of blindness in the world. It has a marked impact on the wellbeing and productivity of individuals and has a major economic impact on healthcare providers. The only means of treating cataract is by surgical intervention. A modern cataract operation generates a capsular bag, which comprises a proportion of the anterior capsule and the entire posterior capsule. The bag remains in situ, partitions the aqueous and vitreous humours, and in the majority of cases, houses an intraocular lens (IOL). The production of a capsular bag following surgery permits a free passage of light along the visual axis through the transparent intraocular lens and thin acellular posterior capsule. Lens epithelial cells, however, remain attached to the anterior capsule, and in response to surgical trauma initiate a wound-healing response that ultimately leads to light scatter and a reduction in visual quality known as posterior capsule opacification (PCO). There are two commonly-described forms of PCO: fibrotic and regenerative. Fibrotic PCO follows classically defined fibrotic processes, namely hyperproliferation, matrix contraction, matrix deposition and epithelial cell trans-differentiation to a myofibroblast phenotype. Regenerative PCO is defined by lens fibre cell differentiation events that give rise to Soemmerring's ring and Elschnig's pearls and becomes evident at a later stage than the fibrotic form. Both fibrotic and regenerative forms of PCO contribute to a reduction in visual quality in patients. This review will highlight the wealth of tools available for PCO research, provide insight into our current knowledge of PCO and discuss putative management of PCO from IOL design to pharmacological interventions.
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Affiliation(s)
- I M Wormstone
- School of Biological Sciences, University of East Anglia, Norwich, UK.
| | - Y M Wormstone
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - A J O Smith
- School of Biological Sciences, University of East Anglia, Norwich, UK
| | - J A Eldred
- School of Biological Sciences, University of East Anglia, Norwich, UK
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21
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Kumaravel M, Uma S, Backiyarani S, Saraswathi MS. Proteomic analysis of somatic embryo development in Musa spp. cv. Grand Naine (AAA). Sci Rep 2020; 10:4501. [PMID: 32161309 PMCID: PMC7066174 DOI: 10.1038/s41598-020-61005-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 11/28/2019] [Indexed: 11/16/2022] Open
Abstract
Somatic embryos are comparable to their zygotic counterparts for morphological traits but are derived from somatic cells through various metabolic regulations, collectively referred as somatic embryogenesis (SE). It has been well exploited for germplasm conservation, genetic engineering, mutation breeding, for artificial seed technology and as a tool for mass multiplication. Though somatic embryo development is an important area of interest in growth, and developmental studies, the underlying molecular mechanism remains unclear. Therefore, understanding the molecular basis behind somatic embryo development can provide insight into the signaling pathways integrating this process. Proteomic analysis of somatic embryo development in cv. Grand Naine (AAA) was carried out to identify the differentially expressed protein during somatic embryo development stages, using two dimensional gel electrophoresis together with mass spectrometry. In total, 25 protein spots were differentially expressed during sequential developmental stages of somatic embryos. Among these, three proteins were uniquely present in 30 days globular stage and six proteins in 60 days old mature somatic embryo. Functional annotation of identified spots showed that major proteins are involved in growth and developmental process (17%) followed by defense response (12%) and signal transportation events (12%). In the early stage, cell division and growth related proteins are involved in the induction of somatic embryos whereas in the late developmental stage, cell wall associated proteins along with stress related proteins played a defensive role against dehydration and osmotic stress and resulted in the maturation of somatic embryo. The identified stage specific proteins are valuable indicators and genetic markers for screening and for media manipulation to improve SE efficiency in recalcitrant crops and varieties.
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Affiliation(s)
- Marimuthu Kumaravel
- Crop Improvement Division, ICAR-National Research Centre for Banana, Thogamalai Main Road, Thayanoor Post, Tiruchirappalli, 102, Tamil Nadu, India
| | - Subbaraya Uma
- Director, ICAR-National Research Centre for Banana, Thogamalai Main Road, Thayanoor Post, Tiruchirappalli, 102, Tamil Nadu, India.
| | - Suthanthiram Backiyarani
- Crop Improvement Division, ICAR-National Research Centre for Banana, Thogamalai Main Road, Thayanoor Post, Tiruchirappalli, 102, Tamil Nadu, India
| | - Marimuthu Somasundaram Saraswathi
- Crop Improvement Division, ICAR-National Research Centre for Banana, Thogamalai Main Road, Thayanoor Post, Tiruchirappalli, 102, Tamil Nadu, India
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22
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Molecular genetics of congenital cataracts. Exp Eye Res 2019; 191:107872. [PMID: 31770519 DOI: 10.1016/j.exer.2019.107872] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 12/18/2022]
Abstract
Congenital cataracts, the most common cause of visual impairment and blindness in children worldwide, have diverse etiologies. According to statistics analysis, about one quarter of congenital cataracts caused by genetic defects. Various mutations of more than one hundred genes have been identified in hereditary cataracts so far. In this review, we briefly summarize recent developments about the genetics, molecular mechanisms, and treatments of congenital cataracts. The studies of these pathogenic mutations and molecular genetics is making it possible for us to comprehend the underlying mechanisms of cataractogenesis and providing new insights into the preventive, diagnostic and therapeutic approaches of cataracts.
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23
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Dewi CU, O'Connor MD. Use of Human Pluripotent Stem Cells to Define Initiating Molecular Mechanisms of Cataract for Anti-Cataract Drug Discovery. Cells 2019; 8:E1269. [PMID: 31627438 PMCID: PMC6830331 DOI: 10.3390/cells8101269] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/08/2019] [Accepted: 10/15/2019] [Indexed: 01/09/2023] Open
Abstract
Cataract is a leading cause of blindness worldwide. Currently, restoration of vision in cataract patients requires surgical removal of the cataract. Due to the large and increasing number of cataract patients, the annual cost of surgical cataract treatment amounts to billions of dollars. Limited access to functional human lens tissue during the early stages of cataract formation has hampered efforts to develop effective anti-cataract drugs. The ability of human pluripotent stem (PS) cells to make large numbers of normal or diseased human cell types raises the possibility that human PS cells may provide a new avenue for defining the molecular mechanisms responsible for different types of human cataract. Towards this end, methods have been established to differentiate human PS cells into both lens cells and transparent, light-focusing human micro-lenses. Sensitive and quantitative assays to measure light transmittance and focusing ability of human PS cell-derived micro-lenses have also been developed. This review will, therefore, examine how human PS cell-derived lens cells and micro-lenses might provide a new avenue for development of much-needed drugs to treat human cataract.
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Affiliation(s)
- Chitra Umala Dewi
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.
| | - Michael D O'Connor
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.
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24
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Disatham J, Chauss D, Gheyas R, Brennan L, Blanco D, Daley L, Menko AS, Kantorow M. Lens differentiation is characterized by stage-specific changes in chromatin accessibility correlating with differentiation state-specific gene expression. Dev Biol 2019; 453:86-104. [PMID: 31136738 PMCID: PMC6667291 DOI: 10.1016/j.ydbio.2019.04.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/16/2019] [Accepted: 04/16/2019] [Indexed: 11/24/2022]
Abstract
Changes in chromatin accessibility regulate the expression of multiple genes by controlling transcription factor access to key gene regulatory sequences. Here, we sought to establish a potential function for altered chromatin accessibility in control of key gene expression events during lens cell differentiation by establishing genome-wide chromatin accessibility maps specific for four distinct stages of lens cell differentiation and correlating specific changes in chromatin accessibility with genome-wide changes in gene expression. ATAC sequencing was employed to generate chromatin accessibility profiles that were correlated with the expression profiles of over 10,000 lens genes obtained by high-throughput RNA sequencing at the same stages of lens cell differentiation. Approximately 90,000 regions of the lens genome exhibited distinct changes in chromatin accessibility at one or more stages of lens differentiation. Over 1000 genes exhibited high Pearson correlation coefficients (r > 0.7) between altered expression levels at specific stages of lens cell differentiation and changes in chromatin accessibility in potential promoter (-7.5kbp/+2.5kbp of the transcriptional start site) and/or other potential cis-regulatory regions ( ±10 kb of the gene body). Analysis of these regions identified consensus binding sequences for multiple transcription factors including members of the TEAD, FOX, and NFAT families of transcription factors as well as HIF1a, RBPJ and IRF1. Functional mapping of genes with high correlations between altered chromatin accessibility and differentiation state-specific gene expression changes identified multiple families of proteins whose expression could be regulated through changes in chromatin accessibility including those governing lens structure (BFSP1,BFSP2), gene expression (Pax-6, Sox 2), translation (TDRD7), cell-cell communication (GJA1), autophagy (FYCO1), signal transduction (SMAD3, EPHA2), and lens transparency (CRYBB1, CRYBA4). These data provide a novel relationship between altered chromatin accessibility and lens differentiation and they identify a wide-variety of lens genes and functions that could be regulated through altered chromatin accessibility. The data also point to a large number of potential DNA regulatory sequences and transcription factors whose functional analysis is likely to provide insight into novel regulatory mechanisms governing the lens differentiation program.
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Affiliation(s)
- Joshua Disatham
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Daniel Chauss
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Rifah Gheyas
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Lisa Brennan
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - David Blanco
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Lauren Daley
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - A Sue Menko
- Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Marc Kantorow
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
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25
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Kabir MH, Patrick R, Ho JWK, O'Connor MD. Identification of active signaling pathways by integrating gene expression and protein interaction data. BMC SYSTEMS BIOLOGY 2018; 12:120. [PMID: 30598083 PMCID: PMC6311899 DOI: 10.1186/s12918-018-0655-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background Signaling pathways are the key biological mechanisms that transduce extracellular signals to affect transcription factor mediated gene regulation within cells. A number of computational methods have been developed to identify the topological structure of a specific signaling pathway using protein-protein interaction data, but they are not designed for identifying active signaling pathways in an unbiased manner. On the other hand, there are statistical methods based on gene sets or pathway data that can prioritize likely active signaling pathways, but they do not make full use of active pathway structure that link receptor, kinases and downstream transcription factors. Results Here, we present a method to simultaneously predict the set of active signaling pathways, together with their pathway structure, by integrating protein-protein interaction network and gene expression data. We evaluated the capacity for our method to predict active signaling pathways for dental epithelial cells, ocular lens epithelial cells, human pluripotent stem cell-derived lens epithelial cells, and lens fiber cells. This analysis showed our approach could identify all the known active pathways that are associated with tooth formation and lens development. Conclusions The results suggest that SPAGI can be a useful approach to identify the potential active signaling pathways given a gene expression profile. Our method is implemented as an open source R package, available via https://github.com/VCCRI/SPAGI/. Electronic supplementary material The online version of this article (10.1186/s12918-018-0655-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Md Humayun Kabir
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia.,Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,Department of Computer Science and Engineering, University of Rajshahi, Rajshahi, Bangladesh
| | - Ralph Patrick
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia.,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia.,Stem Cells Australia, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Joshua W K Ho
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW, Australia. .,St. Vincent's Clinical School, University of New South Wales, Sydney, NSW, Australia. .,School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China.
| | - Michael D O'Connor
- School of Medicine, Western Sydney University, Campbelltown, NSW, Australia. .,Molecular Medicine Research Group, Western Sydney University, Campbelltown, NSW, Australia.
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Ankyrin-G regulated epithelial phenotype is required for mouse lens morphogenesis and growth. Dev Biol 2018; 446:119-131. [PMID: 30562487 DOI: 10.1016/j.ydbio.2018.12.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 12/13/2018] [Accepted: 12/14/2018] [Indexed: 11/24/2022]
Abstract
Epithelial cell polarity, adhesion, proliferation, differentiation and survival are essential for morphogenesis of various organs and tissues including the ocular lens. The molecular mechanisms regulating the lens epithelial phenotype however, are not well understood. Here we investigated the role of scaffolding protein ankyrin-G (AnkG) in mouse lens development by conditional suppression of AnkG expression using the Cre-LoxP recombination approach. AnkG, which serves to link integral membrane proteins to the spectrin/actin cytoskeleton, was found to distribute predominantly to the lateral membranes of lens epithelium with several isoforms of the protein being detected in the mouse lens. Conditional deficiency of AnkG impaired mouse lens morphogenesis starting from embryonic stage E15.5, with neonatal (P1) AnkG cKO lenses exhibiting overt abnormalities in shape, size, epithelial cell height, sheet length and lateral membrane assembly together with defective fiber cell orientation relative to lenses from littermate AnkG floxed or Cre expressing mice. Severe disruptions in E-cadherin/β-catenin-based adherens junctions, and the membrane organization of spectrin-actin cytoskeleton, ZO-1, connexin-50 and Na+-K+-ATPase were noted in AnkG deficient lenses, along with detection in lens epithelium of α-smooth muscle actin, a marker of epithelial to mesenchymal transition. Moreover, lens epithelial cell proliferation and survival were severely compromised while differentiation appears to be normal in AnkG deficient mouse lenses. Collectively, these results indicate that AnkG regulates establishment of the epithelial phenotype via lateral membrane assembly, stabilization of E-cadherin-based cell-cell junctions, polarity and membrane organization of transport and adhesion proteins and the spectrin-actin skeleton, and provide evidence for an obligatory role for AnkG in lens morphogenesis and growth.
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27
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McGreal-Estrada RS, Wolf LV, Cvekl A. Promoter-enhancer looping and shadow enhancers of the mouse αA-crystallin locus. Biol Open 2018; 7:bio.036897. [PMID: 30404901 PMCID: PMC6310886 DOI: 10.1242/bio.036897] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Gene regulation by enhancers is important for precise temporal and spatial gene expression. Enhancers can drive gene expression regardless of their location, orientation or distance from the promoter. Changes in chromatin conformation and chromatin looping occur to bring the promoter and enhancers into close proximity. αA-crystallin ranks among one of the most abundantly expressed genes and proteins in the mammalian lens. The αA-crystallin locus is characterized by a 16 kb chromatin domain marked by two distal enhancers, 5′ DCR1 and 3′ DCR3. Here we used chromatin conformation capture (3C) analysis and transgenic approaches to analyze temporal control of the mouse αA-crystallin gene. We find that DCR1 is necessary, but not sufficient alone to drive expression at E10.5 in the mouse lens pit. Chromatin looping revealed interaction between the promoter and the region 3′ to DCR1, identifying a novel enhancer region in the αA-crystallin locus. We determined that this novel enhancer region, DCR1S, recapitulates the temporal control by DCR1. Acting as shadow enhancers, DCR1 and DCR1S are able to control expression in the lens vesicle at E11.5. It remains to be elucidated however, which region of the αA-crystallin locus is responsible for expression in the lens pit at E10.5. Summary: The αA-crystallin ranks amongst the most highly expressed tissue-specific genes. It is an advantageous model system to probe both promoter-enhancer looping and to identify distal enhancers and their temporal/spatial activities.
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Affiliation(s)
- Rebecca S McGreal-Estrada
- Departments Ophthalmology and Visual Sciences and Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave, Ullmann 123, Bronx, NY 10461, USA
| | - Louise V Wolf
- Departments Ophthalmology and Visual Sciences and Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave, Ullmann 123, Bronx, NY 10461, USA.,Office of Research Services (ORS), Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place - Box 1120, New York, NY 10029-6574
| | - Ales Cvekl
- Departments Ophthalmology and Visual Sciences and Department of Genetics, Albert Einstein College of Medicine, 1300 Morris Park Ave, Ullmann 123, Bronx, NY 10461, USA
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28
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Martynova E, Bouchard M, Musil LS, Cvekl A. Identification of Novel Gata3 Distal Enhancers Active in Mouse Embryonic Lens. Dev Dyn 2018; 247:1186-1198. [PMID: 30295986 PMCID: PMC6246825 DOI: 10.1002/dvdy.24677] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 09/30/2018] [Accepted: 10/01/2018] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The tissue-specific transcriptional programs during normal development require tight control by distal cis-regulatory elements, such as enhancers, with specific DNA sequences recognized by transcription factors, coactivators, and chromatin remodeling enzymes. Gata3 is a sequence-specific DNA-binding transcription factor that regulates formation of multiple tissues and organs, including inner ear, lens, mammary gland, T-cells, urogenital system, and thyroid gland. In the eye, Gata3 has a highly restricted expression domain in the posterior part of the lens vesicle; however, the underlying regulatory mechanisms are unknown. RESULTS Here we describe the identification of a novel bipartite Gata3 lens-specific enhancer located ∼18 kb upstream from its transcriptional start site. We also found that a 5-kb Gata3 promoter possesses low activity in the lens. The bipartite enhancer contains arrays of AP-1, Ets-, and Smad1/5-binding sites as well as binding sites for lens-associated DNA-binding factors. Transient transfection studies of the promoter with the bipartite enhancer showed enhanced activation by BMP4 and FGF2. CONCLUSIONS These studies identify a novel distal enhancer of Gata3 with high activity in lens and indicate that BMP and FGF signaling can up-regulate expression of Gata3 in differentiating lens fiber cells through the identified Gata3 enhancer and promoter elements. Developmental Dynamics 247:1186-1198, 2018. © 2018 The Authors. Developmental Dynamics published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Elena Martynova
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, New York
| | - Maxime Bouchard
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Linda S Musil
- Department of Biochemistry and Molecular Biology, Oregon Health Science University, Portland, Oregon
| | - Ales Cvekl
- Departments of Ophthalmology and Visual Sciences and Genetics, Albert Einstein College of Medicine, Bronx, New York
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29
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Young LK, Jarrin M, Saunter CD, Quinlan RA, Girkin JM. Non-invasive in vivo quantification of the developing optical properties and graded index of the embryonic eye lens using SPIM. BIOMEDICAL OPTICS EXPRESS 2018; 9:2176-2188. [PMID: 29760979 PMCID: PMC5946780 DOI: 10.1364/boe.9.002176] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 03/22/2018] [Accepted: 03/23/2018] [Indexed: 06/08/2023]
Abstract
Graded refractive index lenses are inherent to advanced visual systems in animals. By understanding their formation and local optical properties, significant potential for improved ocular healthcare may be realized. We report a novel technique measuring the developing optical power of the eye lens, in a living animal, by exploiting the orthogonal imaging modality of a selective plane illumination microscope (SPIM). We have quantified the maturation of the lenticular refractive index at three different visible wavelengths using a combined imaging and ray tracing approach. We demonstrate that the method can be used with transgenic and vital dye labeling as well as with both fixed and living animals. Using a key eye lens morphogen and its inhibitor, we have measured their effects both on lens size and on refractive index. Our technique provides insights into the mechanisms involved in the development of this natural graded index micro-lens and its associated optical properties.
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Affiliation(s)
- Laura K Young
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, UK
- Biophysical Sciences Institute, Durham University, South Road, Durham, DH1 3LE, UK
- Joint first authors
| | - Miguel Jarrin
- Biophysical Sciences Institute, Durham University, South Road, Durham, DH1 3LE, UK
- Department of Biosciences, Durham University, Upper Mountjoy, Stockton Road, Durham, DH1 3LE, UK
- Joint first authors
| | - Christopher D Saunter
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, UK
- Biophysical Sciences Institute, Durham University, South Road, Durham, DH1 3LE, UK
| | - Roy A Quinlan
- Biophysical Sciences Institute, Durham University, South Road, Durham, DH1 3LE, UK
- Department of Biosciences, Durham University, Upper Mountjoy, Stockton Road, Durham, DH1 3LE, UK
| | - John M Girkin
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, UK
- Biophysical Sciences Institute, Durham University, South Road, Durham, DH1 3LE, UK
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30
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Barui A, Chowdhury F, Pandit A, Datta P. Rerouting mesenchymal stem cell trajectory towards epithelial lineage by engineering cellular niche. Biomaterials 2018; 156:28-44. [DOI: 10.1016/j.biomaterials.2017.11.036] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 10/22/2017] [Accepted: 11/21/2017] [Indexed: 02/06/2023]
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31
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Murphy P, Kabir MH, Srivastava T, Mason ME, Dewi CU, Lim S, Yang A, Djordjevic D, Killingsworth MC, Ho JWK, Harman DG, O'Connor MD. Light-focusing human micro-lenses generated from pluripotent stem cells model lens development and drug-induced cataract in vitro. Development 2018; 145:dev.155838. [PMID: 29217756 PMCID: PMC5825866 DOI: 10.1242/dev.155838] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 11/15/2017] [Indexed: 12/14/2022]
Abstract
Cataracts cause vision loss and blindness by impairing the ability of the ocular lens to focus light onto the retina. Various cataract risk factors have been identified, including drug treatments, age, smoking and diabetes. However, the molecular events responsible for these different forms of cataract are ill-defined, and the advent of modern cataract surgery in the 1960s virtually eliminated access to human lenses for research. Here, we demonstrate large-scale production of light-focusing human micro-lenses from spheroidal masses of human lens epithelial cells purified from differentiating pluripotent stem cells. The purified lens cells and micro-lenses display similar morphology, cellular arrangement, mRNA expression and protein expression to human lens cells and lenses. Exposing the micro-lenses to the emergent cystic fibrosis drug Vx-770 reduces micro-lens transparency and focusing ability. These human micro-lenses provide a powerful and large-scale platform for defining molecular disease mechanisms caused by cataract risk factors, for anti-cataract drug screening and for clinically relevant toxicity assays.
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Affiliation(s)
- Patricia Murphy
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Md Humayun Kabir
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia.,Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Tarini Srivastava
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Michele E Mason
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Chitra U Dewi
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Seakcheng Lim
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Andrian Yang
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - Djordje Djordjevic
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - Murray C Killingsworth
- Electron Microscopy Laboratory, NSW Health Pathology and Correlative Microscopy Facility, Ingham Institute, Liverpool, NSW 2170, Australia
| | - Joshua W K Ho
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Sydney, NSW 2010, Australia
| | - David G Harman
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia.,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Michael D O'Connor
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia .,Medical Sciences Research Group, Western Sydney University, Campbelltown, NSW 2560, Australia
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32
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Abstract
Pediatric cataract is a leading cause of childhood blindness. Untreated cataracts in children lead to tremendous social, economical, and emotional burden to the child, family, and society. Blindness related to pediatric cataract can be treated with early identification and appropriate management. Most cases are diagnosed on routine screening whereas some may be diagnosed after the parents have noticed leukocoria or strabismus. Etiology of pediatric cataract is varied and diagnosis of specific etiology aids in prognostication and effective management. Pediatric cataract surgery has evolved over years, and with improving knowledge of myopic shift and axial length growth, outcomes of these patients have become more predictable. Favorable outcomes depend not only on effective surgery, but also on meticulous postoperative care and visual rehabilitation. Hence, it is the combined effort of parents, surgeons, anesthesiologists, pediatricians, and optometrists that can make all the difference.
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Affiliation(s)
| | - Ganesh Pillay
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
| | - Chirakshi Dhull
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
| | - Esha Agarwal
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
| | - Manish Mahabir
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
| | - Pulak Aggarwal
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, AIIMS, New Delhi, India
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Tomlinson MS, Bommarito PA, Martin EM, Smeester L, Fichorova RN, Onderdonk AB, Kuban KCK, O’Shea TM, Fry RC. Microorganisms in the human placenta are associated with altered CpG methylation of immune and inflammation-related genes. PLoS One 2017; 12:e0188664. [PMID: 29240761 PMCID: PMC5730116 DOI: 10.1371/journal.pone.0188664] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/10/2017] [Indexed: 12/26/2022] Open
Abstract
Microorganisms in the placenta have been linked to adverse pregnancy outcomes as well as neonatal illness. Inflammation in the placenta has been identified as a contributing factor in this association, but the underlying biological mechanisms are not yet fully understood. The placental epigenome may serve as an intermediate between placental microbes and inflammation, contributing to adverse outcomes in the offspring. In the present study, genome-wide DNA methylation (n = 486,428 CpG sites) of 84 placentas was analyzed in relation to 16 species of placental microorganisms using samples collected from the Extremely Low Gestation Age Newborns (ELGAN) cohort. A total of n = 1,789 CpG sites, corresponding to n = 1,079 genes, displayed differential methylation (q<0.1) in relation to microorganisms. The altered genes encode for proteins that are involved in immune/inflammatory responses, specifically the NF-κB signaling pathway. These data support bacteria-dependent epigenetic patterning in the placenta and provide potential insight into mechanisms that associate the presence of microorganisms in the placenta to pregnancy and neonatal outcomes. This study lays the foundation for investigations of the placental microbiome and its role in placental function.
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Affiliation(s)
- Martha Scott Tomlinson
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Paige A. Bommarito
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Elizabeth M. Martin
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Lisa Smeester
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Raina N. Fichorova
- Laboratory of Genital Tract Biology, Department of Obstetrics and Gynecology, Harvard Medical School and Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
| | - Andrew B. Onderdonk
- Department of Pathology, Harvard Medical School and Brigham and Women’s Hospital, Boston, Massachusetts, United States of America
| | - Karl C. K. Kuban
- Division of Pediatric Neurology, Department of Pediatrics, Boston Medical Center, Boston, Massachusetts, United States of America
| | - T. Michael O’Shea
- Department of Pediatrics, School of Medicine, University of North Carolina, Chapel Hill, North Carolina, United States of America
| | - Rebecca C. Fry
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina, United States of America
- * E-mail:
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34
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Petrova RS, Webb KF, Vaghefi E, Walker K, Schey KL, Donaldson PJ. Dynamic functional contribution of the water channel AQP5 to the water permeability of peripheral lens fiber cells. Am J Physiol Cell Physiol 2017; 314:C191-C201. [PMID: 29118028 DOI: 10.1152/ajpcell.00214.2017] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Although the functionality of the lens water channels aquaporin 1 (AQP1; epithelium) and AQP0 (fiber cells) is well established, less is known about the role of AQP5 in the lens. Since in other tissues AQP5 functions as a regulated water channel with a water permeability (PH2O) some 20 times higher than AQP0, AQP5 could function to modulate PH2O in lens fiber cells. To test this possibility, a fluorescence dye dilution assay was used to calculate the relative PH2O of epithelial cells and fiber membrane vesicles isolated from either the mouse or rat lens, in the absence and presence of HgCl2, an inhibitor of AQP1 and AQP5. Immunolabeling of lens sections and fiber membrane vesicles from mouse and rat lenses revealed differences in the subcellular distributions of AQP5 in the outer cortex between species, with AQP5 being predominantly membranous in the mouse but predominantly cytoplasmic in the rat. In contrast, AQP0 labeling was always membranous in both species. This species-specific heterogeneity in AQP5 membrane localization was mirrored in measurements of PH2O, with only fiber membrane vesicles isolated from the mouse lens, exhibiting a significant Hg2+-sensitive contribution to PH2O. When rat lenses were first organ cultured, immunolabeling revealed an insertion of AQP5 into cortical fiber cells, and a significant increase in Hg2+-sensitive PH2O was detected in membrane vesicles. Our results show that AQP5 forms functional water channels in the rodent lens, and they suggest that dynamic membrane insertion of AQP5 may regulate water fluxes in the lens by modulating PH2O in the outer cortex.
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Affiliation(s)
- Rosica S Petrova
- Department of Physiology, School of Medical Sciences, University of Auckland , Auckland , New Zealand
| | - Kevin F Webb
- Department of Physiology, School of Medical Sciences, University of Auckland , Auckland , New Zealand.,Optics and Photonics Research Group, Department of Electrical and Electronic Engineering, University of Nottingham , Nottingham , United Kingdom
| | - Ehsan Vaghefi
- School of Optometry and Vision Sciences, New Zealand National Eye Centre, University of Auckland , Auckland , New Zealand
| | - Kerry Walker
- Department of Physiology, School of Medical Sciences, University of Auckland , Auckland , New Zealand
| | - Kevin L Schey
- Department of Biochemistry, Vanderbilt University , Nashville, Tennessee
| | - Paul J Donaldson
- Department of Physiology, School of Medical Sciences, University of Auckland , Auckland , New Zealand.,School of Optometry and Vision Sciences, New Zealand National Eye Centre, University of Auckland , Auckland , New Zealand
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35
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Cvekl A, Zhang X. Signaling and Gene Regulatory Networks in Mammalian Lens Development. Trends Genet 2017; 33:677-702. [PMID: 28867048 DOI: 10.1016/j.tig.2017.08.001] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/27/2017] [Accepted: 08/01/2017] [Indexed: 11/16/2022]
Abstract
Ocular lens development represents an advantageous system in which to study regulatory mechanisms governing cell fate decisions, extracellular signaling, cell and tissue organization, and the underlying gene regulatory networks. Spatiotemporally regulated domains of BMP, FGF, and other signaling molecules in late gastrula-early neurula stage embryos generate the border region between the neural plate and non-neural ectoderm from which multiple cell types, including lens progenitor cells, emerge and undergo initial tissue formation. Extracellular signaling and DNA-binding transcription factors govern lens and optic cup morphogenesis. Pax6, c-Maf, Hsf4, Prox1, Sox1, and a few additional factors regulate the expression of the lens structural proteins, the crystallins. Extensive crosstalk between a diverse array of signaling pathways controls the complexity and order of lens morphogenetic processes and lens transparency.
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Affiliation(s)
- Ales Cvekl
- Departments of Genetics and Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Xin Zhang
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.
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36
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Maddala R, Rao PV. Switching of α-Catenin From Epithelial to Neuronal Type During Lens Epithelial Cell Differentiation. Invest Ophthalmol Vis Sci 2017; 58:3445-3455. [PMID: 28692740 PMCID: PMC5505122 DOI: 10.1167/iovs.17-21539] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Purpose Ocular lens fiber cell elongation, differentiation, and compaction are associated with extensive reorganization of cell adhesive interactions and cytoskeleton; however, our knowledge of proteins critical to these events is still evolving. This study characterizes the distribution pattern of neuronal-specific α-catenin (αN-catenin) and its interaction with the N-cadherin–associated adherens junctions (AJs) and their stability in the mouse lens fibers. Methods Expression and distribution of αN-catenin in developing mouse and adult human lenses was determined by RT-PCR, immunoblot, and immunofluorescence analyses. Characterization of αN-catenin and N-cadherin interacting proteins and colocalization analyses were performed using immunoprecipitation, mass spectrometry, and confocal imaging. Effects of periaxin deficiency on the stability of lens fiber cell AJs were evaluated using perixin-null mice. Results αN-catenin exhibits discrete distribution to lens fibers in both mouse and human lenses, undergoing a robust up-regulation during fiber cell differentiation and maturation. Epithelial-specific α-catenin (αE-catenin), in contrast, distributes primarily to the lens epithelium. αN-catenin and N-cadherin reciprocally coimmunoprecipitate and colocalize along with β-catenin, actin, spectrin, vinculin, Armadillo repeat protein deleted in velo-cardio-facial syndrome homolog, periaxin, and ankyrin-B in lens fibers. Fiber cells from periaxin-null mouse lenses revealed disrupted N-cadherin/αN-catenin–based AJs. Conclusions These results suggest that the discrete shift in α-catenin expression from αE-catenin to αN-catenin subtype that occurs during lens epithelial cell differentiation may play a key role in fiber cell cytoarchitecture by regulating the assembly and stability of N-cadherin–based AJs. This study also provides evidence for the importance of the fiber cell–specific cytoskeletal interacting periaxin, in the stability of N-cadherin/αN-catenin–based AJs in lens fibers.
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Affiliation(s)
- Rupalatha Maddala
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Ponugoti Vasantha Rao
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States 2Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, United States
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37
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Logan CM, Rajakaruna S, Bowen C, Radice GL, Robinson ML, Menko AS. N-cadherin regulates signaling mechanisms required for lens fiber cell elongation and lens morphogenesis. Dev Biol 2017; 428:118-134. [PMID: 28552735 DOI: 10.1016/j.ydbio.2017.05.022] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 05/15/2017] [Accepted: 05/15/2017] [Indexed: 12/14/2022]
Abstract
Tissue development and regeneration involve high-ordered morphogenetic processes that are governed by elements of the cytoskeleton in conjunction with cell adhesion molecules. Such processes are particularly important in the lens whose structure dictates its function. Studies of our lens-specific N-cadherin conditional knockout mouse (N-cadcKO) revealed an essential role for N-cadherin in the migration of the apical tips of differentiating lens fiber cells along the apical surfaces of the epithelium, a region termed the Epithelial Fiber Interface (EFI), that is necessary for normal fiber cell elongation and the morphogenesis. Studies of the N-cadcKO lens suggest that N-cadherin function in fiber cell morphogenesis is linked to the activation of Rac1 and myosin II, both signaling pathways central to the regulation of cell motility including determining the directionality of cellular movement. The absence of N-cadherin did not disrupt lateral contacts between fiber cells during development, and the maintenance of Aquaporin-0 and increased expression of EphA2 at cell-cell interfaces suggests that these molecules may function in this role. E-cadherin was maintained in newly differentiating fiber cells without interfering with expression of lens-specific differentiation proteins but was not able to replace N-cadherin function in these cells. The dependence of migration of the fiber cell apical domains along the EFI for lens morphogenesis on N-cadherin provides new insight into the process of tissue development.
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Affiliation(s)
- Caitlin M Logan
- Thomas Jefferson University, Pathology Anatomy and Cell Biology, Philadelphia, PA, United States
| | - Suren Rajakaruna
- Thomas Jefferson University, Pathology Anatomy and Cell Biology, Philadelphia, PA, United States
| | - Caitlin Bowen
- Thomas Jefferson University, Pathology Anatomy and Cell Biology, Philadelphia, PA, United States
| | - Glenn L Radice
- Thomas Jefferson University, Pathology Anatomy and Cell Biology, Philadelphia, PA, United States
| | - Michael L Robinson
- Department of Biology, Cell Molecular and Structural Biology Graduate Program, Miami University, Oxford, OH, United States
| | - A Sue Menko
- Thomas Jefferson University, Pathology Anatomy and Cell Biology, Philadelphia, PA, United States.
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38
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Bassnett S, Šikić H. The lens growth process. Prog Retin Eye Res 2017; 60:181-200. [PMID: 28411123 DOI: 10.1016/j.preteyeres.2017.04.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 04/06/2017] [Accepted: 04/10/2017] [Indexed: 01/17/2023]
Abstract
The factors that regulate the size of organs to ensure that they fit within an organism are not well understood. A simple organ, the ocular lens serves as a useful model with which to tackle this problem. In many systems, considerable variance in the organ growth process is tolerable. This is almost certainly not the case in the lens, which in addition to fitting comfortably within the eyeball, must also be of the correct size and shape to focus light sharply onto the retina. Furthermore, the lens does not perform its optical function in isolation. Its growth, which continues throughout life, must therefore be coordinated with that of other tissues in the optical train. Here, we review the lens growth process in detail, from pioneering clinical investigations in the late nineteenth century to insights gleaned more recently in the course of cell and molecular studies. During embryonic development, the lens forms from an invagination of surface ectoderm. Consequently, the progenitor cell population is located at its surface and differentiated cells are confined to the interior. The interactions that regulate cell fate thus occur within the obligate ellipsoidal geometry of the lens. In this context, mathematical models are particularly appropriate tools with which to examine the growth process. In addition to identifying key growth determinants, such models constitute a framework for integrating cell biological and optical data, helping clarify the relationship between gene expression in the lens and image quality at the retinal plane.
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Affiliation(s)
- Steven Bassnett
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine, USA.
| | - Hrvoje Šikić
- Department of Mathematics, Faculty of Science, University of Zagreb, Croatia
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Šikić H, Shi Y, Lubura S, Bassnett S. A full lifespan model of vertebrate lens growth. ROYAL SOCIETY OPEN SCIENCE 2017; 4:160695. [PMID: 28280571 PMCID: PMC5319337 DOI: 10.1098/rsos.160695] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/05/2016] [Indexed: 06/06/2023]
Abstract
The mathematical determinants of vertebrate organ growth have yet to be elucidated fully. Here, we utilized empirical measurements and a dynamic branching process-based model to examine the growth of a simple organ system, the mouse lens, from E14.5 until the end of life. Our stochastic model used difference equations to model immigration and emigration between zones of the lens epithelium and included some deterministic elements, such as cellular footprint area. We found that the epithelial cell cycle was shortened significantly in the embryo, facilitating the rapid growth that marks early lens development. As development progressed, epithelial cell division becomes non-uniform and four zones, each with a characteristic proliferation rate, could be discerned. Adjustment of two model parameters, proliferation rate and rate of change in cellular footprint area, was sufficient to specify all growth trajectories. Modelling suggested that the direction of cellular migration across zonal boundaries was sensitive to footprint area, a phenomenon that may isolate specific cell populations. Model runs consisted of more than 1000 iterations, in each of which the stochastic behaviour of thousands of cells was followed. Nevertheless, sequential runs were almost superimposable. This remarkable degree of precision was attributed, in part, to the presence of non-mitotic flanking regions, which constituted a path by which epithelial cells could escape the growth process. Spatial modelling suggested that clonal clusters of about 50 cells are produced during migration and that transit times lengthen significantly at later stages, findings with implications for the formation of certain types of cataract.
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Affiliation(s)
- Hrvoje Šikić
- Department of Ophthalmology and Visual Sciences, Washington University, St Louis, MO 63130, USA
- Department of Mathematics, University of Zagreb, Zagreb, Croatia
| | - Yanrong Shi
- Department of Ophthalmology and Visual Sciences, Washington University, St Louis, MO 63130, USA
| | - Snježana Lubura
- Department of Mathematics, University of Zagreb, Zagreb, Croatia
| | - Steven Bassnett
- Department of Ophthalmology and Visual Sciences, Washington University, St Louis, MO 63130, USA
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Gerlee P, Basanta D, Anderson ARA. The Influence of Cellular Characteristics on the Evolution of Shape Homeostasis. ARTIFICIAL LIFE 2017; 23:424-448. [PMID: 28786729 DOI: 10.1162/artl_a_00240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The importance of individual cells in a developing multicellular organism is well known, but precisely how the individual cellular characteristics of those cells collectively drive the emergence of robust, homeostatic structures is less well understood. For example, cell communication via a diffusible factor allows for information to travel across large distances within the population, and cell polarization makes it possible to form structures with a particular orientation, but how do these processes interact to produce a more robust and regulated structure? In this study we investigate the ability of cells with different cellular characteristics to grow and maintain homeostatic structures. We do this in the context of an individual-based model where cell behavior is driven by an intracellular network that determines the cell phenotype. More precisely, we investigated evolution with 96 different permutations of our model, where cell motility, cell death, long-range growth factor (LGF), short-range growth factor (SGF), and cell polarization were either present or absent. The results show that LGF has the largest positive influence on the fitness of the evolved solutions. SGF and polarization also contribute, but all other capabilities essentially increase the search space, effectively making it more difficult to achieve a solution. By perturbing the evolved solutions, we found that they are highly robust to both mutations and wounding. In addition, we observed that by evolving solutions in more unstable environments they produce structures that were more robust and adaptive. In conclusion, our results suggest that robust collective behavior is most likely to evolve when cells are endowed with long-range communication, cell polarisation, and selection pressure from an unstable environment.
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Affiliation(s)
- Philip Gerlee
- Chalmers University of Technology and University of Gothenburg
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Donaldson PJ, Grey AC, Maceo Heilman B, Lim JC, Vaghefi E. The physiological optics of the lens. Prog Retin Eye Res 2017; 56:e1-e24. [DOI: 10.1016/j.preteyeres.2016.09.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/09/2016] [Accepted: 09/13/2016] [Indexed: 11/17/2022]
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Holt R, Ugur Iseri SA, Wyatt AW, Bax DA, Gold Diaz D, Santos C, Broadgate S, Dunn R, Bruty J, Wallis Y, McMullan D, Ogilvie C, Gerrelli D, Zhang Y, Ragge N. Identification and functional characterisation of genetic variants in OLFM2 in children with developmental eye disorders. Hum Genet 2016; 136:119-127. [PMID: 27844144 DOI: 10.1007/s00439-016-1745-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/06/2016] [Indexed: 12/30/2022]
Abstract
Anophthalmia, microphthalmia, and coloboma are a genetically heterogeneous spectrum of developmental eye disorders and affect around 30 per 100,000 live births. OLFM2 encodes a secreted glycoprotein belonging to the noelin family of olfactomedin domain-containing proteins that modulate the timing of neuronal differentiation during development. OLFM2 SNPs have been associated with open angle glaucoma in a case-control study, and knockdown of Olfm2 in zebrafish results in reduced eye size. From a cohort of 258 individuals with developmental eye anomalies, we identified two with heterozygous variants in OLFM2: an individual with bilateral microphthalmia carrying a de novo 19p13.2 microdeletion involving OLFM2 and a second individual with unilateral microphthalmia and contralateral coloboma who had a novel single base change in the 5' untranslated region. Dual luciferase assays demonstrated that the latter variant causes a significant decrease in expression of OLFM2. Furthermore, RNA in situ hybridisation experiments using human developmental tissue revealed expression in relevant structures, including the lens vesicle and optic cup. Our study indicates that OLFM2 is likely to be important in mammalian eye development and disease and should be considered as a gene for human ocular anomalies.
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Affiliation(s)
- R Holt
- Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | - S A Ugur Iseri
- Department of Genetics, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - A W Wyatt
- Department of Urologic Sciences, University of British Columbia, Vancouver, Canada
| | - D A Bax
- Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | - D Gold Diaz
- Developmental Biology & Cancer Programme, UCL Great Ormond Street Institute of Child Health, London, UK
| | - C Santos
- Developmental Biology & Cancer Programme, UCL Great Ormond Street Institute of Child Health, London, UK
| | - S Broadgate
- Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK.,Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - R Dunn
- Department of Genetics, Viapath, Guy's Hospital, London, UK
| | - J Bruty
- West Midlands Regional Genetics Laboratory, Birmingham Women's Hospital, Birmingham, UK
| | - Y Wallis
- West Midlands Regional Genetics Laboratory, Birmingham Women's Hospital, Birmingham, UK
| | - D McMullan
- West Midlands Regional Genetics Laboratory, Birmingham Women's Hospital, Birmingham, UK
| | - C Ogilvie
- Department of Cytogenetics, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - D Gerrelli
- Developmental Biology & Cancer Programme, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Y Zhang
- Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK
| | - Nicola Ragge
- Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK. .,Clinical Genetics Unit, West Midlands Regional Genetics Service, Birmingham Women's Hospital, Birmingham, B15 2TG, UK.
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Thein T, de Melo J, Zibetti C, Clark BS, Juarez F, Blackshaw S. Control of lens development by Lhx2-regulated neuroretinal FGFs. Development 2016; 143:3994-4002. [PMID: 27633990 PMCID: PMC5117141 DOI: 10.1242/dev.137760] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 09/01/2016] [Indexed: 01/07/2023]
Abstract
Fibroblast growth factor (FGF) signaling is an essential regulator of lens epithelial cell proliferation and survival, as well as lens fiber cell differentiation. However, the identities of these FGF factors, their source tissue and the genes that regulate their synthesis are unknown. We have found that Chx10-Cre;Lhx2lox/lox mice, which selectively lack Lhx2 expression in neuroretina from E10.5, showed an early arrest in lens fiber development along with severe microphthalmia. These mutant animals showed reduced expression of multiple neuroretina-expressed FGFs and canonical FGF-regulated genes in neuroretina. When FGF expression was genetically restored in Lhx2-deficient neuroretina of Chx10-Cre;Lhx2lox/lox mice, we observed a partial but nonetheless substantial rescue of the defects in lens cell proliferation, survival and fiber differentiation. These data demonstrate that neuroretinal expression of Lhx2 and neuroretina-derived FGF factors are crucial for lens fiber development in vivo.
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Affiliation(s)
- Thuzar Thein
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Jimmy de Melo
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Cristina Zibetti
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Brian S Clark
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Felicia Juarez
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Ophthalmology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Department of Neurology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Center for Human Systems Biology, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
- Institute for Cell Engineering, Johns Hopkins University School of Medicine, 733 N. Broadway, Baltimore, MD 21205, USA
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Pathania M, Wang Y, Simirskii VN, Duncan MK. β1-integrin controls cell fate specification in early lens development. Differentiation 2016; 92:133-147. [PMID: 27596755 PMCID: PMC5159248 DOI: 10.1016/j.diff.2016.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/05/2016] [Accepted: 08/09/2016] [Indexed: 02/03/2023]
Abstract
Integrins are heterodimeric cell surface molecules that mediate cell-extracellular matrix (ECM) adhesion, ECM assembly, and regulation of both ECM and growth factor induced signaling. However, the developmental context of these diverse functions is not clear. Loss of β1-integrin from the lens vesicle (mouse E10.5) results in abnormal exit of anterior lens epithelial cells (LECs) from the cell cycle and their aberrant elongation toward the presumptive cornea by E12.5. These cells lose expression of LEC markers and initiate expression of the Maf (also known as c-Maf) and Prox1 transcription factors as well as other lens fiber cell markers. β1-integrin null LECs also upregulate the ERK, AKT and Smad1/5/8 phosphorylation indicative of BMP and FGF signaling. By E14.5, β1-integrin null lenses have undergone a complete conversion of all lens epithelial cells into fiber cells. These data suggest that shortly after lens vesicle closure, β1-integrin blocks inappropriate differentiation of the lens epithelium into fibers, potentially by inhibiting BMP and/or FGF receptor activation. Thus, β1-integrin has an important role in fine-tuning the response of the early lens to the gradient of growth factors that regulate lens fiber cell differentiation.
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Affiliation(s)
- Mallika Pathania
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Vladimir N Simirskii
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Melinda K Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
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Lee S, Shatadal S, Griep AE. Dlg-1 Interacts With and Regulates the Activities of Fibroblast Growth Factor Receptors and EphA2 in the Mouse Lens. Invest Ophthalmol Vis Sci 2016; 57:707-18. [PMID: 26906157 PMCID: PMC4771194 DOI: 10.1167/iovs.15-17727] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
PURPOSE We previously showed that Discs large-1 (Dlg-1) regulates lens fiber cell structure and the fibroblast growth factor receptor (Fgfr) signaling pathway, a pathway required for fiber cell differentiation. Herein, we investigated the mechanism through which Dlg-1 regulates Fgfr signaling. METHODS Immunofluorescence was used to measure levels of Fgfr1, Fgfr2, and activated Fgfr signaling intermediates, pErk and pAkt, in control and Dlg-1-deficient lenses that were haplodeficient for Fgfr1 or Fgfr2. Immunoblotting was used to measure levels of N-cadherin, EphA2, β-catenin, and tyrosine-phosphorylated EphA2, Fgfr1, Fgfr2, and Fgfr3 in cytoskeletal-associated and cytosolic fractions of control and Dlg-1-deficient lenses. Complex formation between Dlg-1, N-cadherin, β-catenin, Fgfr1, Fgfr2, Fgfr3, and EphA2 was assessed by coimmunoprecipitation. RESULTS Lenses deficient for Dlg-1 and haplodeficient for Fgfr1 or Fgfr2 showed increased levels of Fgfr2 or Fgfr1, respectively. Levels of pErk and pAkt correlated with the level of Fgfr2. N-cadherin was reduced in the cytoskeletal-associated fraction and increased in the cytosolic fraction of Dlg-1-deficient lenses. Dlg-1 complexed with β-catenin, EphA2, Fgfr1, Fgfr2, and Fgfr3. EphA2 complexed with N-cadherin, β-catenin, Fgfr1, Fgfr2, and Fgfr3. Levels of these interactions were altered in Dlg-1-deficient lenses. Loss of Dlg-1 led to changes in Fgfr1, Fgfr2, Fgfr3, and EphA2 levels and to greater changes in the levels of their activation. CONCLUSIONS Dlg-1 complexes with and regulates the activities of EphA2, Fgfr1, Fgfr2, and Fgfr3. As EphA2 contains a Psd95/Dlg/ZO-1 (PDZ) binding motif, whereas Fgfrs do not, we propose that the PDZ protein, Dlg-1, modulates Fgfr signaling through regulation of EphA2.
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AGE-RAGE interaction in the TGFβ2-mediated epithelial to mesenchymal transition of human lens epithelial cells. Glycoconj J 2016; 33:631-43. [PMID: 27263094 DOI: 10.1007/s10719-016-9686-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/18/2016] [Accepted: 05/24/2016] [Indexed: 01/12/2023]
Abstract
Basement membrane (BM) proteins accumulate chemical modifications with age. One such modification is glycation, which results in the formation of advanced glycation endproducts (AGEs). In a previous study, we reported that AGEs in the human lens capsule (BM) promote the TGFβ2-mediated epithelial-to-mesenchymal transition (EMT) of lens epithelial cells, which we proposed as a mechanism for posterior capsule opacification (PCO) or secondary cataract formation. In this study, we investigated the role of a receptor for AGEs (RAGE) in the TGFβ2-mediated EMT in a human lens epithelial cell line (FHL124). RAGE was present in FHL124 cells, and its levels were unaltered in cells cultured on either native or AGE-modified BM or upon treatment with TGFβ2. RAGE overexpression significantly enhanced the TGFβ2-mediated EMT responses in cells cultured on AGE-modified BM compared with the unmodified matrix. In contrast, treatment of cells with a RAGE antibody or EN-RAGE (an endogenous ligand for RAGE) resulted in a significant reduction in the TGFβ2-mediated EMT response. This was accompanied by a reduction in TGFβ2-mediated Smad signaling and ROS generation. These results imply that the interaction of matrix AGEs with RAGE plays a role in the TGFβ2-mediated EMT of lens epithelial cells and suggest that the blockade of RAGE could be a strategy to prevent PCO and other age-associated fibrosis.
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47
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Intrinsic and extrinsic regulatory mechanisms are required to form and maintain a lens of the correct size and shape. Exp Eye Res 2016; 156:34-40. [PMID: 27109030 DOI: 10.1016/j.exer.2016.04.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 04/13/2016] [Accepted: 04/16/2016] [Indexed: 02/04/2023]
Abstract
Understanding how tissues and organs acquire and maintain an appropriate size and shape remains one of the most challenging areas in developmental biology. The eye lens represents an excellent system to provide insights into regulatory mechanisms because in addition to its relative simplicity in cellular composition (being made up of only two forms of cells, epithelial and fiber cells), these cells must become organized to generate the precise spheroidal arrangement that delivers normal lens function. Epithelial and fiber cells also represent spatially distinct proliferation and differentiation compartments, respectively, and an ongoing balance between these domains must be tightly regulated so that the lens achieves and maintains appropriate dimensions during growth and ageing. Recent research indicates that reciprocal inductive interactions mediated by Wnt-Frizzled and Notch-Jagged signaling pathways are important for maintaining and organizing these compartments. The Hippo-Yap pathway has also been implicated in maintaining the epithelial progenitor compartment and regulating growth processes. Thus, whilst some molecules and mechanisms have been identified, further work in this important area is needed to provide a clearer understanding of how lens size and shape is regulated.
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48
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Audette DS, Scheiblin DA, Duncan MK. The molecular mechanisms underlying lens fiber elongation. Exp Eye Res 2016; 156:41-49. [PMID: 27015931 DOI: 10.1016/j.exer.2016.03.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 03/14/2016] [Accepted: 03/16/2016] [Indexed: 12/28/2022]
Abstract
Lens fiber cells are highly elongated cells with complex membrane morphologies that are critical for the transparency of the ocular lens. Investigations into the molecular mechanisms underlying lens fiber cell elongation were first reported in the 1960s, however, our understanding of the process is still poor nearly 50 years later. This review summarizes what is currently hypothesized about the regulation of lens fiber cell elongation along with the available experimental evidence, and how this information relates to what is known about the regulation of cell shape/elongation in other cell types, particularly neurons.
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Affiliation(s)
- Dylan S Audette
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - David A Scheiblin
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Melinda K Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
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49
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Wu JJ, Wu W, Tholozan FM, Saunter CD, Girkin JM, Quinlan RA. A dimensionless ordered pull-through model of the mammalian lens epithelium evidences scaling across species and explains the age-dependent changes in cell density in the human lens. J R Soc Interface 2016; 12:20150391. [PMID: 26236824 PMCID: PMC4528606 DOI: 10.1098/rsif.2015.0391] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We present a mathematical (ordered pull-through; OPT) model of the cell-density profile for the mammalian lens epithelium together with new experimental data. The model is based upon dimensionless parameters, an important criterion for inter-species comparisons where lens sizes can vary greatly (e.g. bovine (approx. 18 mm); mouse (approx. 2 mm)) and confirms that mammalian lenses scale with size. The validated model includes two parameters: β/α, which is the ratio of the proliferation rate in the peripheral and in the central region of the lens; and γGZ, a dimensionless pull-through parameter that accounts for the cell transition and exit from the epithelium into the lens body. Best-fit values were determined for mouse, rat, rabbit, bovine and human lens epithelia. The OPT model accounts for the peak in cell density at the periphery of the lens epithelium, a region where cell proliferation is concentrated and reaches a maximum coincident with the germinative zone. The β/α ratio correlates with the measured FGF-2 gradient, a morphogen critical to lens cell survival, proliferation and differentiation. As proliferation declines with age, the OPT model predicted age-dependent changes in cell-density profiles, which we observed in mouse and human lenses.
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Affiliation(s)
- Jun Jie Wu
- Biophysical Sciences Institute and School of Engineering and Computing Sciences, Durham University, Durham DH1 3LE, UK
- e-mail:
| | - Weiju Wu
- Biophysical Sciences Institute and School of Biological and Biomedical Sciences, Durham University, Durham DH1 3LE, UK
| | - Frederique M. Tholozan
- Biophysical Sciences Institute and School of Biological and Biomedical Sciences, Durham University, Durham DH1 3LE, UK
| | - Christopher D. Saunter
- Biophysical Sciences Institute and Department of Physics, Durham University, Durham DH1 3LE, UK
| | - John M. Girkin
- Biophysical Sciences Institute and Department of Physics, Durham University, Durham DH1 3LE, UK
| | - Roy A. Quinlan
- Biophysical Sciences Institute and School of Biological and Biomedical Sciences, Durham University, Durham DH1 3LE, UK
- e-mail:
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50
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Rothe M, Kanwal N, Dietmann P, Seigfried F, Hempel A, Schütz D, Reim D, Engels R, Linnemann A, Schmeisser MJ, Bockmann J, Kühl M, Boeckers TM, Kühl SJ. An Epha4/Sipa1l3/Wnt pathway regulates eye development and lens maturation. Development 2016; 144:321-333. [DOI: 10.1242/dev.147462] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 12/06/2016] [Indexed: 01/21/2023]
Abstract
The signal-induced proliferation associated family of proteins comprises four members, SIPA1 and SIPA1L1-1L3. Mutations of the human SIPA1L3 gene result in congenital cataracts. In Xenopus, loss of Sipa1l3 function led to a severe eye phenotype that was distinguished by smaller eyes and lenses including lens fiber cell maturation defects. We found a direct interaction between Sipa1l3 and Epha4, building a functional platform for proper ocular development. Epha4 deficiency phenocopied loss of Sipa1l3 and rescue experiments demonstrated that Epha4 acts up-stream of Sipa1l3 during eye development. Both, Sipa1l3 and Epha4 are required for early eye specification. The ocular phenotype, upon loss of either Epha4 or Sipa1l3, was partially mediated by rax. We demonstrated that canonical Wnt signaling is inhibited downstream of Epha4/Sipa1l3 during normal eye development. Depletion of either Sipa1l3 or Epha4 resulted in an up-regulation of axin2 expression, a direct Wnt/β-catenin target gene. In line with this, Sipa1l3 or Epha4 depletion could be rescued by blocking Wnt/β-catenin or activating non-canonical Wnt signaling. We therefore conclude that this pathomechanism prevents proper eye development and maturation of lens fiber cells resulting in congenital cataracts.
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Affiliation(s)
- Melanie Rothe
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
- International Graduate School in Molecular Medicine Ulm, 89081 Ulm University, Ulm, Germany
| | - Noreen Kanwal
- Institute for Anatomy and Cell Biology, Ulm University, 89081 Ulm, Germany
- International Graduate School in Molecular Medicine Ulm, 89081 Ulm University, Ulm, Germany
| | - Petra Dietmann
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
| | - Franziska Seigfried
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
- International Graduate School in Molecular Medicine Ulm, 89081 Ulm University, Ulm, Germany
| | - Annemarie Hempel
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
- International Graduate School in Molecular Medicine Ulm, 89081 Ulm University, Ulm, Germany
| | - Desiree Schütz
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
| | - Dominik Reim
- Institute for Anatomy and Cell Biology, Ulm University, 89081 Ulm, Germany
- International Graduate School in Molecular Medicine Ulm, 89081 Ulm University, Ulm, Germany
| | - Rebecca Engels
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
| | - Alexander Linnemann
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
| | - Michael J. Schmeisser
- Institute for Anatomy and Cell Biology, Ulm University, 89081 Ulm, Germany
- Department of Neurology, Ulm University, 89081 Ulm, Germany
| | - Juergen Bockmann
- Institute for Anatomy and Cell Biology, Ulm University, 89081 Ulm, Germany
| | - Michael Kühl
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
| | - Tobias M. Boeckers
- Institute for Anatomy and Cell Biology, Ulm University, 89081 Ulm, Germany
| | - Susanne J. Kühl
- Institute of Biochemistry and Molecular Biology, Ulm University, 89081 Ulm, Germany
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