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Mori Y, Smith S, Wang J, Munjal A. Versican controlled by Lmx1b regulates hyaluronate density and hydration for semicircular canal morphogenesis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.07.592968. [PMID: 38766227 PMCID: PMC11100707 DOI: 10.1101/2024.05.07.592968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
During inner ear semicircular canal morphogenesis in zebrafish, patterned canal-genesis zones express genes for extracellular matrix component synthesis. These include hyaluronan and the hyaluronan-binding chondroitin sulfate proteoglycan Versican, which are abundant in the matrices of many developing organs. Charged hyaluronate polymers play a key role in canal morphogenesis through osmotic swelling. However, the developmental factor(s) that control the synthesis of the matrix components and regulation of hyaluronate density and swelling are unknown. Here, we identify the transcription factor, Lmx1b, as a positive transcriptional regulator of hyaluronan, Versican, and chondroitin synthesis genes crucial for canal morphogenesis. We show that Versican regulates hyaluronan density through its protein core, whereas the charged chondroitin side chains contribute to the osmotic swelling of hyaluronate. Versican-tuned properties of hyaluronate matrices may be a broadly used mechanism in morphogenesis with important implications for understanding diseases where these matrices are impaired, and for hydrogel engineering for tissue regeneration.
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Affiliation(s)
- Yusuke Mori
- Department of Cell Biology, Duke University School of Medicine, Durham NC 27710
| | - Sierra Smith
- Department of Cell Biology, Duke University School of Medicine, Durham NC 27710
| | - Jiacheng Wang
- Department of Cell Biology, Duke University School of Medicine, Durham NC 27710
| | - Akankshi Munjal
- Department of Cell Biology, Duke University School of Medicine, Durham NC 27710
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2
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Sokolova N, Zilova L, Wittbrodt J. Unravelling the link between embryogenesis and adult stem cell potential in the ciliary marginal zone: A comparative study between mammals and teleost fish. Cells Dev 2023; 174:203848. [PMID: 37172718 DOI: 10.1016/j.cdev.2023.203848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/03/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023]
Abstract
The discovery and study of adult stem cells have revolutionized regenerative medicine by offering new opportunities for treating various medical conditions. Anamniote stem cells, which retain their full proliferative capacity and full differentiation range throughout their lifetime, harbour a greater potential compared to mammalian adult stem cells, which only exhibit limited stem cell potential. Therefore, understanding the mechanisms underlying these differences is of significant interest. In this review, we examine the similarities and differences of adult retinal stem cells in anamniotes and mammals, from their embryonic stages in the optic vesicle to their residence in the postembryonic retinal stem cell niche, the ciliary marginal zone located in the retinal periphery. In anamniotes, developing precursors of retinal stem cells are exposed to various environmental cues during their migration in the complex morphogenetic remodelling of the optic vesicle to the optic cup. In contrast, their mammalian counterparts in the retinal periphery are primarily instructed by neighbouring tissues once they are in place. We explore the distinct modes of optic cup morphogenesis in mammals and teleost fish and highlight molecular mechanisms governing morphogenesis and stem cells instruction. The review concludes with the molecular mechanisms of ciliary marginal zone formation and offers a perspective on the impact of comparative single cell transcriptomic studies to reveal the evolutionary similarities and differences.
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Affiliation(s)
- Natalia Sokolova
- Centre for Organismal Studies Heidelberg, Germany; Heidelberg Biosciences International Graduate School, Germany
| | - Lucie Zilova
- Centre for Organismal Studies Heidelberg, Germany.
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3
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Diacou R, Nandigrami P, Fiser A, Liu W, Ashery-Padan R, Cvekl A. Cell fate decisions, transcription factors and signaling during early retinal development. Prog Retin Eye Res 2022; 91:101093. [PMID: 35817658 PMCID: PMC9669153 DOI: 10.1016/j.preteyeres.2022.101093] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 12/30/2022]
Abstract
The development of the vertebrate eyes is a complex process starting from anterior-posterior and dorso-ventral patterning of the anterior neural tube, resulting in the formation of the eye field. Symmetrical separation of the eye field at the anterior neural plate is followed by two symmetrical evaginations to generate a pair of optic vesicles. Next, reciprocal invagination of the optic vesicles with surface ectoderm-derived lens placodes generates double-layered optic cups. The inner and outer layers of the optic cups develop into the neural retina and retinal pigment epithelium (RPE), respectively. In vitro produced retinal tissues, called retinal organoids, are formed from human pluripotent stem cells, mimicking major steps of retinal differentiation in vivo. This review article summarizes recent progress in our understanding of early eye development, focusing on the formation the eye field, optic vesicles, and early optic cups. Recent single-cell transcriptomic studies are integrated with classical in vivo genetic and functional studies to uncover a range of cellular mechanisms underlying early eye development. The functions of signal transduction pathways and lineage-specific DNA-binding transcription factors are dissected to explain cell-specific regulatory mechanisms underlying cell fate determination during early eye development. The functions of homeodomain (HD) transcription factors Otx2, Pax6, Lhx2, Six3 and Six6, which are required for early eye development, are discussed in detail. Comprehensive understanding of the mechanisms of early eye development provides insight into the molecular and cellular basis of developmental ocular anomalies, such as optic cup coloboma. Lastly, modeling human development and inherited retinal diseases using stem cell-derived retinal organoids generates opportunities to discover novel therapies for retinal diseases.
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Affiliation(s)
- Raven Diacou
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Prithviraj Nandigrami
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Andras Fiser
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Wei Liu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ruth Ashery-Padan
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Ales Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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Self-Organization of the Retina during Eye Development, Retinal Regeneration In Vivo, and in Retinal 3D Organoids In Vitro. Biomedicines 2022; 10:biomedicines10061458. [PMID: 35740479 PMCID: PMC9221005 DOI: 10.3390/biomedicines10061458] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 06/16/2022] [Accepted: 06/18/2022] [Indexed: 11/23/2022] Open
Abstract
Self-organization is a process that ensures histogenesis of the eye retina. This highly intricate phenomenon is not sufficiently studied due to its biological complexity and genetic heterogeneity. The review aims to summarize the existing central theories and ideas for a better understanding of retinal self-organization, as well as to address various practical problems of retinal biomedicine. The phenomenon of self-organization is discussed in the spatiotemporal context and illustrated by key findings during vertebrate retina development in vivo and retinal regeneration in amphibians in situ. Described also are histotypic 3D structures obtained from the disaggregated retinal progenitor cells of birds and retinal 3D organoids derived from the mouse and human pluripotent stem cells. The review highlights integral parts of retinal development in these conditions. On the cellular level, these include competence, differentiation, proliferation, apoptosis, cooperative movements, and migration. On the physical level, the focus is on the mechanical properties of cell- and cell layer-derived forces and on the molecular level on factors responsible for gene regulation, such as transcription factors, signaling molecules, and epigenetic changes. Finally, the self-organization phenomenon is discussed as a basis for the production of retinal organoids, a promising model for a wide range of basic scientific and medical applications.
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Casey MA, Hill JT, Hoshijima K, Bryan CD, Gribble SL, Brown JT, Chien CB, Yost HJ, Kwan KM. Shutdown corner, a large deletion mutant isolated from a haploid mutagenesis screen in zebrafish. G3 (BETHESDA, MD.) 2022; 12:jkab442. [PMID: 35079792 PMCID: PMC9210284 DOI: 10.1093/g3journal/jkab442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022]
Abstract
Morphogenesis, the formation of three-dimensional organ structures, requires precise coupling of genetic regulation and complex cell behaviors. The genetic networks governing many morphogenetic systems, including that of the embryonic eye, are poorly understood. In zebrafish, several forward genetic screens have sought to identify factors regulating eye development. These screens often look for eye defects at stages after the optic cup is formed and when retinal neurogenesis is under way. This approach can make it difficult to identify mutants specific for morphogenesis, as opposed to neurogenesis. To this end, we carried out a forward genetic, small-scale haploid mutagenesis screen in zebrafish (Danio rerio) to identify factors that govern optic cup morphogenesis. We screened ∼100 genomes and isolated shutdown corner (sco), a mutant that exhibits multiple tissue defects and harbors a ∼10-Mb deletion that encompasses 89 annotated genes. Using a combination of live imaging and antibody staining, we found cell proliferation, cell death, and tissue patterning defects in the sco optic cup. We also observed other phenotypes, including paralysis, neuromuscular defects, and ocular vasculature defects. To date, the largest deletion mutants reported in zebrafish are engineered using CRISPR-Cas9 and are less than 300 kb. Because of the number of genes within the deletion interval, shutdown corner [Df(Chr05:sco)z207] could be a useful resource to the zebrafish community, as it may be helpful for gene mapping, understanding genetic interactions, or studying many genes lost in the mutant.
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Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Jonathon T Hill
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT 84602, USA
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Chase D Bryan
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32611, USA
| | - Suzanna L Gribble
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - J Thomas Brown
- Department of Biomedical Informatics, Vanderbilt University, Nashville, TN 37203, USA
| | - Chi-Bin Chien
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - H Joseph Yost
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
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6
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Neurospheres obtained from the ciliary margin of the chicken eye possess positional values and retinal ganglion cells differentiated from them respond to EphA/ephrin-A system. Exp Eye Res 2022; 217:108965. [DOI: 10.1016/j.exer.2022.108965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 12/14/2021] [Accepted: 01/25/2022] [Indexed: 11/23/2022]
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7
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Extracellular hyaluronate pressure shaped by cellular tethers drives tissue morphogenesis. Cell 2021; 184:6313-6325.e18. [PMID: 34942099 PMCID: PMC8722442 DOI: 10.1016/j.cell.2021.11.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 09/29/2021] [Accepted: 11/15/2021] [Indexed: 12/24/2022]
Abstract
How tissues acquire complex shapes is a fundamental question in biology and regenerative medicine. Zebrafish semicircular canals form from invaginations in the otic epithelium (buds) that extend and fuse to form the hubs of each canal. We find that conventional actomyosin-driven behaviors are not required. Instead, local secretion of hyaluronan, made by the enzymes uridine 5'-diphosphate dehydrogenase (ugdh) and hyaluronan synthase 3 (has3), drives canal morphogenesis. Charged hyaluronate polymers osmotically swell with water and generate isotropic extracellular pressure to deform the overlying epithelium into buds. The mechanical anisotropy needed to shape buds into tubes is conferred by a polarized distribution of actomyosin and E-cadherin-rich membrane tethers, which we term cytocinches. Most work on tissue morphogenesis ascribes actomyosin contractility as the driving force, while the extracellular matrix shapes tissues through differential stiffness. Our work inverts this expectation. Hyaluronate pressure shaped by anisotropic tissue stiffness may be a widespread mechanism for powering morphological change in organogenesis and tissue engineering.
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Casey MA, Lusk S, Kwan KM. Build me up optic cup: Intrinsic and extrinsic mechanisms of vertebrate eye morphogenesis. Dev Biol 2021; 476:128-136. [PMID: 33811855 PMCID: PMC8848517 DOI: 10.1016/j.ydbio.2021.03.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 12/16/2022]
Abstract
The basic structure of the eye, which is crucial for visual function, is established during the embryonic process of optic cup morphogenesis. Molecular pathways of specification and patterning are integrated with spatially distinct cell and tissue shape changes to generate the eye, with discrete domains and structural features: retina and retinal pigment epithelium enwrap the lens, and the optic fissure occupies the ventral surface of the eye and optic stalk. Interest in the underlying cell biology of eye morphogenesis has led to a growing body of work, combining molecular genetics and imaging to quantify cellular processes such as adhesion and actomyosin activity. These studies reveal that intrinsic machinery and spatiotemporally specific extrinsic inputs collaborate to control dynamics of cell movements and morphologies. Here we consider recent advances in our understanding of eye morphogenesis, with a focus on the mechanics of eye formation throughout vertebrate systems, including insights and potential opportunities using organoids, which may provide a tractable system to test hypotheses from embryonic models.
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Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Sarah Lusk
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA.
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9
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Revealing hidden genetic diagnoses in the ocular anterior segment disorders. Genet Med 2020; 22:1623-1632. [PMID: 32499604 PMCID: PMC7521990 DOI: 10.1038/s41436-020-0854-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/27/2022] Open
Abstract
Purpose Ocular anterior segment disorders (ASDs) are clinically and genetically heterogeneous, and genetic diagnosis often remains elusive. In this study, we demonstrate the value of a combined analysis protocol using phenotypic, genomic, and pedigree structure data to achieve a genetic conclusion. Methods We utilized a combination of chromosome microarray, exome sequencing, and genome sequencing with structural variant and trio analysis to investigate a cohort of 41 predominantly sporadic cases. Results We identified likely causative variants in 54% (22/41) of cases, including 51% (19/37) of sporadic cases and 75% (3/4) of cases initially referred as familial ASD. Two-thirds of sporadic cases were found to have heterozygous variants, which in most cases were de novo. Approximately one-third (7/22) of genetic diagnoses were found in rarely reported or recently identified ASD genes including PXDN, GJA8, COL4A1, ITPR1, CPAMD8, as well as the new phenotypic association of Axenfeld–Rieger anomaly with a homozygous ADAMTS17 variant. The remainder of the variants were in key ASD genes including FOXC1, PITX2, CYP1B1, FOXE3, and PAX6. Conclusions We demonstrate the benefit of detailed phenotypic, genomic, variant, and segregation analysis to uncover some of the previously “hidden” heritable answers in several rarely reported and newly identified ocular ASD-related disease genes.
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10
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Bryan CD, Casey MA, Pfeiffer RL, Jones BW, Kwan KM. Optic cup morphogenesis requires neural crest-mediated basement membrane assembly. Development 2020; 147:dev181420. [PMID: 31988185 PMCID: PMC7044464 DOI: 10.1242/dev.181420] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 01/13/2020] [Indexed: 12/21/2022]
Abstract
Organogenesis requires precise interactions between a developing tissue and its environment. In vertebrates, the developing eye is surrounded by a complex extracellular matrix as well as multiple mesenchymal cell populations. Disruptions to either the matrix or periocular mesenchyme can cause defects in early eye development, yet in many cases the underlying mechanism is unknown. Here, using multidimensional imaging and computational analyses in zebrafish, we establish that cell movements in the developing optic cup require neural crest. Ultrastructural analysis reveals that basement membrane formation around the developing eye is also dependent on neural crest, but only specifically around the retinal pigment epithelium. Neural crest cells produce the extracellular matrix protein nidogen: impairing nidogen function disrupts eye development, and, strikingly, expression of nidogen in the absence of neural crest partially restores optic cup morphogenesis. These results demonstrate that eye formation is regulated in part by extrinsic control of extracellular matrix assembly.This article has an associated 'The people behind the papers' interview.
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Affiliation(s)
- Chase D Bryan
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Rebecca L Pfeiffer
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Bryan W Jones
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
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11
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Müller WE, Schröder HC, Wang X. Inorganic Polyphosphates As Storage for and Generator of Metabolic Energy in the Extracellular Matrix. Chem Rev 2019; 119:12337-12374. [PMID: 31738523 PMCID: PMC6935868 DOI: 10.1021/acs.chemrev.9b00460] [Citation(s) in RCA: 91] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Indexed: 12/14/2022]
Abstract
Inorganic polyphosphates (polyP) consist of linear chains of orthophosphate residues, linked by high-energy phosphoanhydride bonds. They are evolutionarily old biopolymers that are present from bacteria to man. No other molecule concentrates as much (bio)chemically usable energy as polyP. However, the function and metabolism of this long-neglected polymer are scarcely known, especially in higher eukaryotes. In recent years, interest in polyP experienced a renaissance, beginning with the discovery of polyP as phosphate source in bone mineralization. Later, two discoveries placed polyP into the focus of regenerative medicine applications. First, polyP shows morphogenetic activity, i.e., induces cell differentiation via gene induction, and, second, acts as an energy storage and donor in the extracellular space. Studies on acidocalcisomes and mitochondria provided first insights into the enzymatic basis of eukaryotic polyP formation. In addition, a concerted action of alkaline phosphatase and adenylate kinase proved crucial for ADP/ATP generation from polyP. PolyP added extracellularly to mammalian cells resulted in a 3-fold increase of ATP. The importance and mechanism of this phosphotransfer reaction for energy-consuming processes in the extracellular matrix are discussed. This review aims to give a critical overview about the formation and function of this unique polymer that is capable of storing (bio)chemically useful energy.
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Affiliation(s)
- Werner E.G. Müller
- ERC Advanced Investigator
Grant Research
Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - Heinz C. Schröder
- ERC Advanced Investigator
Grant Research
Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
| | - Xiaohong Wang
- ERC Advanced Investigator
Grant Research
Group at the Institute for Physiological Chemistry, University Medical Center of the Johannes Gutenberg University, Duesbergweg 6, D-55128 Mainz, Germany
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12
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Carney KR, Bryan CD, Gordon HB, Kwan KM. LongAxis: A MATLAB-based program for 3D quantitative analysis of epithelial cell shape and orientation. Dev Biol 2019; 458:1-11. [PMID: 31589834 DOI: 10.1016/j.ydbio.2019.09.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 09/13/2019] [Accepted: 09/27/2019] [Indexed: 10/25/2022]
Abstract
Epithelial morphogenesis, a fundamental aspect of development, generates 3-dimensional tissue structures crucial for organ function. Underlying morphogenetic mechanisms are, in many cases, poorly understood, but mutations that perturb organ development can affect epithelial cell shape and orientation - difficult features to quantify in three dimensions. The basic structure of the eye is established via epithelial morphogenesis: in the embryonic optic cup, the retinal progenitor epithelium enwraps the lens. We previously found that loss of the extracellular matrix protein laminin-alpha1 (lama1) led to mislocalization of apical polarity markers and apparent misorientation of retinal progenitors. We sought to visualize and quantify this phenotype, and determine whether loss of the apical polarity determinant pard3 might rescue the phenotype. To this end, we developed LongAxis, a MATLAB-based program optimized for the retinal progenitor neuroepithelium. LongAxis facilitates 3-dimensional cell segmentation, visualization, and quantification of cell orientation and morphology. Using LongAxis, we find that retinal progenitors in the lama1-/- optic cup are misoriented and slightly less elongated. In the lama1;MZpard3 double mutant, cells are still misoriented, but larger. Therefore, loss of pard3 does not rescue loss of lama1, and in fact uncovers a novel cell size phenotype. LongAxis enables population-level visualization and quantification of retinal progenitor cell orientation and morphology. These results underscore the importance of visualizing and quantifying cell orientation and shape in three dimensions within the retina.
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Affiliation(s)
- Keith R Carney
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Chase D Bryan
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Hannah B Gordon
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA.
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13
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A non-cell-autonomous actin redistribution enables isotropic retinal growth. PLoS Biol 2018. [PMID: 30096143 DOI: 10.1371/journal.pbio.2006018.] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Tissue shape is often established early in development and needs to be scaled isotropically during growth. However, the cellular contributors and ways by which cells interact tissue-wide to enable coordinated isotropic tissue scaling are not yet understood. Here, we follow cell and tissue shape changes in the zebrafish retinal neuroepithelium, which forms a cup with a smooth surface early in development and maintains this architecture as it grows. By combining 3D analysis and theory, we show how a global increase in cell height can maintain tissue shape during growth. Timely cell height increase occurs concurrently with a non-cell-autonomous actin redistribution. Blocking actin redistribution and cell height increase perturbs isotropic scaling and leads to disturbed, folded tissue shape. Taken together, our data show how global changes in cell shape enable isotropic growth of the developing retinal neuroepithelium, a concept that could also apply to other systems.
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14
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Matejčić M, Salbreux G, Norden C. A non-cell-autonomous actin redistribution enables isotropic retinal growth. PLoS Biol 2018; 16:e2006018. [PMID: 30096143 PMCID: PMC6117063 DOI: 10.1371/journal.pbio.2006018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 08/30/2018] [Accepted: 07/31/2018] [Indexed: 11/26/2022] Open
Abstract
Tissue shape is often established early in development and needs to be scaled isotropically during growth. However, the cellular contributors and ways by which cells interact tissue-wide to enable coordinated isotropic tissue scaling are not yet understood. Here, we follow cell and tissue shape changes in the zebrafish retinal neuroepithelium, which forms a cup with a smooth surface early in development and maintains this architecture as it grows. By combining 3D analysis and theory, we show how a global increase in cell height can maintain tissue shape during growth. Timely cell height increase occurs concurrently with a non-cell-autonomous actin redistribution. Blocking actin redistribution and cell height increase perturbs isotropic scaling and leads to disturbed, folded tissue shape. Taken together, our data show how global changes in cell shape enable isotropic growth of the developing retinal neuroepithelium, a concept that could also apply to other systems.
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Affiliation(s)
- Marija Matejčić
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | | | - Caren Norden
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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15
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Extracellular matrix component expression in human pluripotent stem cell-derived retinal organoids recapitulates retinogenesis in vivo and reveals an important role for IMPG1 and CD44 in the development of photoreceptors and interphotoreceptor matrix. Acta Biomater 2018; 74:207-221. [PMID: 29777959 DOI: 10.1016/j.actbio.2018.05.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Revised: 05/07/2018] [Accepted: 05/15/2018] [Indexed: 02/08/2023]
Abstract
The extracellular matrix (ECM) plays an important role in numerous processes including cellular proliferation, differentiation, migration, maturation, adhesion guidance and axonal growth. To date, there has been no detailed analysis of the ECM distribution during retinal ontogenesis in humans and the functional importance of many ECM components is poorly understood. In this study, the expression of key ECM components in adult mouse and monkey retina, developing and adult human retina and retinal organoids derived from human pluripotent stem cells was studied. Our data indicate that basement membrane ECMs (Fibronectin and Collagen IV) were expressed in Bruch's membrane and the inner limiting membrane of the developing human retina, whilst the hyalectins (Versican and Brevican), cluster of differentiation 44 (CD44), photoreceptor-specific ECMs Interphotoreceptor Matrix Proteoglycan 1 (IMPG1) and Interphotoreceptor Matrix Proteoglycan 2 (IMPG2) were detected in the developing interphotoreceptor matrix (IPM). The expression of IMPG1, Versican and Brevican in the developing IPM was conserved between human developing retina and human pluripotent stem cell-derived retinal organoids. Blocking the action of CD44 and IMPG1 in pluripotent stem cell derived retinal organoids affected the development of photoreceptors, their inner/outer segments and connecting cilia and disrupted IPM formation, with IMPG1 having an earlier and more significant impact. Together, our data suggest an important role for IMPG1 and CD44 in the development of photoreceptors and IPM formation during human retinogenesis. STATEMENT OF SIGNIFICANCE The expression and the role of many extracellular matrix (ECM) components during human retinal development is not fully understood. In this study, expression of key ECM components (Collagen IV, Fibronectin, Brevican, Versican, IMPG1 and IMPG2) was investigated during human retinal ontogenesis. Collagen IV and Fibronectin were expressed in Bruch's membrane; whereas Brevican, Versican, IMPG1 & IMPG2 in the developing interphotoreceptor matrix (IPM). Retinal organoids were successfully generated from pluripotent stem cells. The expression of ECM components was examined in the retinal organoids and found to recapitulate human retinal development in vivo. Using functional blocking experiments, we were able to highlight an important role for IMPG1 and CD44 in the development of photoreceptors and IPM formation.
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Dorgau B, Felemban M, Sharpe A, Bauer R, Hallam D, Steel DH, Lindsay S, Mellough C, Lako M. Laminin γ3 plays an important role in retinal lamination, photoreceptor organisation and ganglion cell differentiation. Cell Death Dis 2018; 9:615. [PMID: 29795281 PMCID: PMC5966411 DOI: 10.1038/s41419-018-0648-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/12/2018] [Accepted: 04/26/2018] [Indexed: 01/02/2023]
Abstract
Laminins are heterotrimeric glycoproteins of the extracellular matrix. Eleven different laminin chains have been identified in vertebrates. They are ubiquitously expressed in the human body, with a distinct tissue distribution. Laminin expression in neural retina and their functional role during human retinogenesis is still unknown. This study investigated the laminin expression in human developing and adult retina, showing laminin α1, α5, β1, β2 and γ1 to be predominantly expressed in Bruch's membrane and the inner limiting membrane. Laminin-332 and laminin γ3 expression were mainly observed in the neural retina during retinal histogenesis. These expression patterns were largely conserved in pluripotent stem cell-derived retinal organoids. Blocking of laminin γ3 function in retinal organoids resulted in the disruption of laminar organisation and synapse formation, the loss of photoreceptor organisation and retinal ganglion cells. Our data demonstrate a unique temporal and spatial expression for laminins and reveal a novel role for laminin γ3 during human retinogenesis.
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Affiliation(s)
- Birthe Dorgau
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Majed Felemban
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Alexander Sharpe
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Roman Bauer
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Dean Hallam
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David H Steel
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Susan Lindsay
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Carla Mellough
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, University of Western Australia, Nedlands WA, Australia
| | - Majlinda Lako
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom.
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17
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He GH, Zhang W, Ma YX, Yang J, Chen L, Song J, Chen S. Mesenchymal stem cells-derived exosomes ameliorate blue light stimulation in retinal pigment epithelium cells and retinal laser injury by VEGF-dependent mechanism. Int J Ophthalmol 2018; 11:559-566. [PMID: 29675371 DOI: 10.18240/ijo.2018.04.04] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 02/07/2018] [Indexed: 01/09/2023] Open
Abstract
AIM To observe the effect of exosomes derived from human umbilical cord blood mesenchymal stem cells (hUCMSCs) on the expression of vascular endothelial growth factor-A (VEGF-A) in blue light injured human retinal pigment epithelial (RPE) cells and laser-induced choroidal neovascularization (CNV) in rats. METHODS Exosomes were isolated from hUCMSCs and characterized by transmission electron microscope and Western blot. MSCs-derived exosomes were cultured with RPE cells exposed to blue light. The mRNA and protein expression of VEGF-A were determined by real time-polymerase chain reaction (PCR) and Western blot, respectively. Immunofluorescence assay was used for the detection of the expression level of VEGF-A. We injected different doses of MSCs-derived exosomes intravitreally to observe and compare their effects in a mouse model of laser-induced retinal injury. The histological structure of CNV in rats was inspected by hematoxylin-eosin (HE) staining and fundus fluorescein angiography. The expression of VEGF-A was detected by immunohistochemistry. RESULTS Exosomes exhibited the typical characteristic morphology (cup-shaped) and size (diameter between 50 and 150 nm). The exosomes marker, CD63, and hUCMSCs marker, CD90, showed a robust presence. In vitro, MSCs-derived exosomes downregulated the mRNA(Exo-L: t=6.485, 7.959, 9.286; Exo-M: t=7.517, 10.170, 13.413; Exo-H: t=10.317, 12.234, 14.592, P<0.05) and protein (Exo-L: t=2.945, 4.477, 6.657; Exo-M: t=4.713, 6.421, 8.836; Exo-H: t=6.539, 12.194, 12.783; P<0.05) expression of VEGF-A in RPE cells after blue light stimulation. In vivo, we found that the MSCs-derived exosomes reduced damage, distinctly downregulated VEGF-A (Exo-H: t=0.957, 1.382; P<0.05), and gradually improved the histological structures of CNV for a better visual function (Exo-L: 0.346, Exo-M: 3.382, Exo-H: 8.571; P<0.05). CONCLUSION MSCs-derived exosomes ameliorate blue light stimulation in RPE cells and laser-induced retinal injury via downregulation of VEGF-A.
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Affiliation(s)
- Guang-Hui He
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
| | - Wei Zhang
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
| | - Ying-Xue Ma
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
| | - Jing Yang
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
| | - Li Chen
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
| | - Jian Song
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
| | - Song Chen
- Tianjin Eye Hospital; Tianjin Key Lab of Ophthalmology and Visual Science; Tianjin Eye Institute; Clinical College of Ophthalmology, Tianjin Medical University, Tianjin 300020, China
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18
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Wang J, Zhang W, He GH, Wu B, Chen S. Transfection with CXCR4 potentiates homing of mesenchymal stem cells in vitro and therapy of diabetic retinopathy in vivo. Int J Ophthalmol 2018; 11:766-772. [PMID: 29862173 PMCID: PMC5957026 DOI: 10.18240/ijo.2018.05.08] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 03/01/2018] [Indexed: 12/21/2022] Open
Abstract
AIM To investigate the effect of the overexpression of C-X-C chemokine receptor type 4 (CXCR4) on homing of mesenchymal stem cells (MSCs) in vitro and therapeutic effects of diabetic retinopathy (DR) in vivo. METHODS MSCs were infected by lentivirus constructed with CXCR4. The expression of CXCR4 was examined by immunofluorescence, Western blot, and quantitative polymerase chain reaction. CXCR4-overexpressing MSCs were cultured in vitro to evaluate their chemotaxis, migration, and apoptotic activities. CXCR4-overexpressing MSCs were intravitreally injected to observe and compare their effects in a mouse model of DR. The histological structure of DR in rats was inspected by hematoxylin and eosin staining. The expression of rhodopsin, neuron-specific enolase (NSE), and inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α was examined by Western blot and immunohistochemical analyses. RESULTS The transduction of MSCs by lentivirus was effective, and the transduced MSCs had high expression levels of CXCR4 gene and protein. Improved migration activities were observed in CXCR4-overexpressing MSCs. Further, reduced retinal damage, upregulation of rhodopsin and NSE protein, and downregulation of inflammatory cytokines IL-6 and TNF-α were observed in CXCR4-overexpressing MSCs in vivo. CONCLUSION The homing of MSCs can be enhanced by upregulating CXCR4 levels, possibly improving histological structures of DR. CXCR4-overexpressing MSCs can be a novel strategy for treating DR.
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Affiliation(s)
- Jian Wang
- Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Clinical College of Ophthalmology Tianjin Medical University, Tianjin 300020, China
| | - Wei Zhang
- Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Clinical College of Ophthalmology Tianjin Medical University, Tianjin 300020, China
| | - Guang-Hui He
- Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Clinical College of Ophthalmology Tianjin Medical University, Tianjin 300020, China
| | - Bin Wu
- Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Clinical College of Ophthalmology Tianjin Medical University, Tianjin 300020, China
| | - Song Chen
- Tianjin Eye Hospital, Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin Eye Institute, Clinical College of Ophthalmology Tianjin Medical University, Tianjin 300020, China
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19
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Aose M, Linbo TH, Lawrence O, Senoo T, Raible DW, Clark JI. The occhiolino (occ) mutant Zebrafish, a model for development of the optical function in the biological lens. Dev Dyn 2017; 246:915-924. [PMID: 28422363 PMCID: PMC6800130 DOI: 10.1002/dvdy.24511] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 03/16/2017] [Accepted: 04/03/2017] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Zebrafish visual function depends on quality optics. An F3 screen for developmental mutations in the Zebrafish nervous system was conducted in wild-type (wt) AB Zebrafish exposed to 3 mM of N-ethyl-N-nitrosourea (ENU). RESULTS Mutant offspring, identified in an F3 screen, were characterized by a small pupil, resulting from retinal hypertrophy or hyperplasia and a small lens. Deficits in visual function made feeding difficult after hatching at approximately 5-6 days postfertilization (dpf). Special feeding conditions were necessary for survival of the occhiolino (occ) mutants after 6 dpf. Optokinetic response (OKR) tests measured defects in visual function in the occ mutant, although electroretinograms (ERGs) were normal in the mutant and wt. Consistent with the ERGs, histology found normal retinal structure in the occ mutant and wt Zebrafish. However, lens development was abnormal. Multiphoton imaging of the developmental stages of live embryos confirmed the formation of a secondary mass of lens cells in the developing eye of the mutant Zebrafish at 3-4 dpf, and laminin immunohistochemistry indicated the lens capsule was thin and disorganized in the mutant Zebrafish. CONCLUSIONS The occ Zebrafish is a novel disease model for visual defects associated with abnormal lens development. Developmental Dynamics 246:915-924, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Masamoto Aose
- Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan
| | - Tor H Linbo
- Department of Biological Structure, University of Washington, Seattle, Washington
| | - Owen Lawrence
- Department of Biological Structure, University of Washington, Seattle, Washington
| | - Tadashi Senoo
- Department of Ophthalmology, Dokkyo Medical University, Tochigi, Japan
| | - David W Raible
- Department of Biological Structure, University of Washington, Seattle, Washington
| | - John I Clark
- Department of Biological Structure, University of Washington, Seattle, Washington
- Department of Ophthalmology, University of Washington, Seattle, Washington
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20
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Sedykh I, Yoon B, Roberson L, Moskvin O, Dewey CN, Grinblat Y. Zebrafish zic2 controls formation of periocular neural crest and choroid fissure morphogenesis. Dev Biol 2017; 429:92-104. [PMID: 28689736 DOI: 10.1016/j.ydbio.2017.07.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 05/30/2017] [Accepted: 07/06/2017] [Indexed: 12/31/2022]
Abstract
The vertebrate retina develops in close proximity to the forebrain and neural crest-derived cartilages of the face and jaw. Coloboma, a congenital eye malformation, is associated with aberrant forebrain development (holoprosencephaly) and with craniofacial defects (frontonasal dysplasia) in humans, suggesting a critical role for cross-lineage interactions during retinal morphogenesis. ZIC2, a zinc-finger transcription factor, is linked to human holoprosencephaly. We have previously used morpholino assays to show zebrafish zic2 functions in the developing forebrain, retina and craniofacial cartilage. We now report that zebrafish with genetic lesions in zebrafish zic2 orthologs, zic2a and zic2b, develop with retinal coloboma and craniofacial anomalies. We demonstrate a requirement for zic2 in restricting pax2a expression and show evidence that zic2 function limits Hh signaling. RNA-seq transcriptome analysis identified an early requirement for zic2 in periocular neural crest as an activator of alx1, a transcription factor with essential roles in craniofacial and ocular morphogenesis in human and zebrafish. Collectively, these data establish zic2 mutant zebrafish as a powerful new genetic model for in-depth dissection of cell interactions and genetic controls during craniofacial complex development.
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Affiliation(s)
- Irina Sedykh
- Department of Integrative Biology, University of Wisconsin, Madison, WI 53706, USA; Department of Neuroscience, University of Wisconsin, Madison, WI 53706, USA
| | - Baul Yoon
- Department of Integrative Biology, University of Wisconsin, Madison, WI 53706, USA; Department of Neuroscience, University of Wisconsin, Madison, WI 53706, USA; Genetics Ph. D. Training Program, University of Wisconsin, Madison, WI 53706, USA
| | - Laura Roberson
- Department of Integrative Biology, University of Wisconsin, Madison, WI 53706, USA; Department of Neuroscience, University of Wisconsin, Madison, WI 53706, USA
| | - Oleg Moskvin
- Primate Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Colin N Dewey
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Yevgenya Grinblat
- Department of Integrative Biology, University of Wisconsin, Madison, WI 53706, USA; Department of Neuroscience, University of Wisconsin, Madison, WI 53706, USA; McPherson Eye Research Institute, University of Wisconsin, Madison, WI, 53706, USA.
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21
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Kino J, Tsukaguchi H, Kimata T, Nguyen HT, Nakano Y, Miyake N, Matsumoto N, Kaneko K. Nephron development and extrarenal features in a child with congenital nephrotic syndrome caused by null LAMB2 mutations. BMC Nephrol 2017; 18:220. [PMID: 28683731 PMCID: PMC5501564 DOI: 10.1186/s12882-017-0632-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 06/22/2017] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Congenital nephrotic syndrome (CNS) is a rare disorder caused by various structural and developmental defects of glomeruli. It occurs typically as an isolated kidney disorder but associates sometimes with other systemic, extrarenal manifestations. CASE PRESENTATIONS An infant presented with severe CNS, which progressed rapidly to renal failure at age of 3 months and death at 27 months. The clinical phenotypes and genetic causes were studied, including the renal pathology at autopsy. Besides the CNS, the affected child had remarkable right-side predominant eye-ball hypoplasia with bilateral anterior chamber dysgenesis (microcoria). Brain MRI revealed grossly normal development in the cerebrum, cerebellum, and brain stem. Auditory brainstem responses were bilaterally blunted, suggesting a defective auditory system. At autopsy, both kidneys were mildly atrophied with persistent fetal lobulation. Microscopic examination showed a diffuse global sclerosis. However, despite of the smaller size of glomeruli, the nephron number remained similar to that of the age-matched control. Whole-exome sequencing revealed that the affected child was compound heterozygous for novel truncating LAMB2 mutations: a 4-bp insertion (p.Gly1693Alafs*8) and a splicing donor-site substitution (c.1225 + 1G > A), presumably deleting the coiled-coil domains that form the laminin 5-2-1 heterotrimer complex. CONCLUSIONS Our case represents a variation of Pierson syndrome that accompanies CNS with unilateral ocular hypoplasia. The average number but smaller glomeruli could reflect either mal-development or glomerulosclerosis. Heterogeneous clinical expression of LAMB2 defects may associate with the difference in fetal β1 subtype compensation among affected tissues. Further study is necessary to evaluate incidence and features of auditory defect under LAMB2 deficiency.
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Affiliation(s)
- Jiro Kino
- Department of Pediatrics, Kansai Medical University, 2-5-1 Shimachi, Hirakata, Osaka, 573-1010, Japan
| | - Hiroyasu Tsukaguchi
- Second Department of Internal Medicine, Kansai Medical University, 2-5-1 Shinmachi Hirakata, Osaka, 573-1010, Japan.
| | - Takahisa Kimata
- Department of Pediatrics, Kansai Medical University, 2-5-1 Shimachi, Hirakata, Osaka, 573-1010, Japan
| | - Huan Thanh Nguyen
- Second Department of Internal Medicine, Kansai Medical University, 2-5-1 Shinmachi Hirakata, Osaka, 573-1010, Japan
| | - Yorika Nakano
- Department of Pathology and Laboratory Medicine, Kansai Medical University, Osaka, Japan.,Present Address: Department of Histopathology and Cytology, Japanese Red Cross Kyoto Daini Hospital, Kyoto, Japan
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan
| | - Kazunari Kaneko
- Department of Pediatrics, Kansai Medical University, 2-5-1 Shimachi, Hirakata, Osaka, 573-1010, Japan
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22
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Oltean A, Huang J, Beebe DC, Taber LA. Tissue growth constrained by extracellular matrix drives invagination during optic cup morphogenesis. Biomech Model Mechanobiol 2016; 15:1405-1421. [PMID: 26984743 DOI: 10.1007/s10237-016-0771-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 02/05/2016] [Indexed: 12/19/2022]
Abstract
In the early embryo, the eyes form initially as relatively spherical optic vesicles (OVs) that protrude from both sides of the brain tube. Each OV grows until it contacts and adheres to the overlying surface ectoderm (SE) via an extracellular matrix (ECM) that is secreted by the SE and OV. The OV and SE then thicken and bend inward (invaginate) to create the optic cup (OC) and lens vesicle, respectively. While constriction of cell apices likely plays a role in SE invagination, the mechanisms that drive OV invagination are poorly understood. Here, we used experiments and computational modeling to explore the hypothesis that the ECM locally constrains the growing OV, forcing it to invaginate. In chick embryos, we examined the need for the ECM by (1) removing SE at different developmental stages and (2) exposing the embryo to collagenase. At relatively early stages of invagination (Hamburger-Hamilton stage HH14[Formula: see text]), removing the SE caused the curvature of the OV to reverse as it 'popped out' and became convex, but the OV remained concave at later stages (HH15) and invaginated further during subsequent culture. Disrupting the ECM had a similar effect, with the OV popping out at early to mid-stages of invagination (HH14[Formula: see text] to HH14[Formula: see text]). These results suggest that the ECM is required for the early stages but not the late stages of OV invagination. Microindentation tests indicate that the matrix is considerably stiffer than the cellular OV, and a finite-element model consisting of a growing spherical OV attached to a relatively stiff layer of ECM reproduced the observed behavior, as well as measured temporal changes in OV curvature, wall thickness, and invagination depth reasonably well. Results from our study also suggest that the OV grows relatively uniformly, while the ECM is stiffer toward the center of the optic vesicle. These results are consistent with our matrix-constraint hypothesis, providing new insight into the mechanics of OC (early retina) morphogenesis.
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Affiliation(s)
- Alina Oltean
- Department of Biomedical Engineering, Washington University, One Brookings Drive, Campus Box 1097, Saint Louis, MO, 63130-4899, USA.
| | - Jie Huang
- Department of Ophthalmology and Visual Sciences, Washington University, Saint Louis, MO, 63130, USA
| | - David C Beebe
- Department of Ophthalmology and Visual Sciences, Washington University, Saint Louis, MO, 63130, USA
| | - Larry A Taber
- Department of Biomedical Engineering, Washington University, One Brookings Drive, Campus Box 1097, Saint Louis, MO, 63130-4899, USA
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