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Rasys AM, Wegerski A, Trainor PA, Hufnagel RB, Menke DB, Lauderdale JD. Dynamic changes in ocular shape during human development and its implications for retina fovea formation. Bioessays 2024; 46:e2300054. [PMID: 38037292 DOI: 10.1002/bies.202300054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 10/10/2023] [Accepted: 10/24/2023] [Indexed: 12/02/2023]
Abstract
The human fovea is known for its distinctive pit-like appearance, which results from the displacement of retinal layers superficial to the photoreceptors cells. The photoreceptors are found at high density within the foveal region but not the surrounding retina. Efforts to elucidate the mechanisms responsible for these unique features have ruled out cell death as an explanation for pit formation and changes in cell proliferation as the cause of increased photoreceptor density. These findings have led to speculation that mechanical forces acting within and on the retina during development underly the formation of foveal architecture. Here we review eye morphogenesis and retinal remodeling in human embryonic development. Our meta-analysis of the literature suggests that fovea formation is a protracted process involving dynamic changes in ocular shape that start early and continue throughout most of human embryonic development. From these observations, we propose a new model for fovea development.
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Affiliation(s)
- Ashley M Rasys
- Department of Cellular Biology, The University of Georgia, Athens, Georgia, USA
| | - Andrew Wegerski
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Paul A Trainor
- Stowers Institute for Medical Research, Kansas City, Missouri, USA
- Department of Anatomy & Cell Biology, The University of Kansas School of Medicine, Kansas City, Kansas, USA
| | - Robert B Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Douglas B Menke
- Department of Genetics, The University of Georgia, Athens, Georgia, USA
| | - James D Lauderdale
- Department of Cellular Biology, The University of Georgia, Athens, Georgia, USA
- Neuroscience Division of the Biomedical and Health Sciences Institute, The University of Georgia, Athens, Georgia, USA
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2
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Casey MA, Lusk S, Kwan KM. Eye Morphogenesis in Vertebrates. Annu Rev Vis Sci 2023; 9:221-243. [PMID: 37040791 DOI: 10.1146/annurev-vision-100720-111125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Proper eye structure is essential for visual function: Multiple essential eye tissues must take shape and assemble into a precise three-dimensional configuration. Accordingly, alterations to eye structure can lead to pathological conditions of visual impairment. Changes in eye shape can also be adaptive over evolutionary time. Eye structure is first established during development with the formation of the optic cup, which contains the neural retina, retinal pigment epithelium, and lens. This crucial yet deceptively simple hemispherical structure lays the foundation for all later elaborations of the eye. Building on descriptions of the embryonic eye that started with hand drawings and micrographs, the field is beginning to identify mechanisms driving dynamic changes in three-dimensional cell and tissue shape. A combination of molecular genetics, imaging, and pharmacological approaches is defining connections among transcription factors, signaling pathways, and the intracellular machinery governing the emergence of this crucial structure.
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Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA; , ,
| | - Sarah Lusk
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA; , ,
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA; , ,
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3
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Ovadia S, Cui G, Elkon R, Cohen-Gulkar M, Zuk-Bar N, Tuoc T, Jing N, Ashery-Padan R. SWI/SNF complexes are required for retinal pigmented epithelium differentiation and for the inhibition of cell proliferation and neural differentiation programs. Development 2023; 150:dev201488. [PMID: 37522516 PMCID: PMC10482007 DOI: 10.1242/dev.201488] [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: 11/27/2022] [Accepted: 07/14/2023] [Indexed: 08/01/2023]
Abstract
During embryonic development, tissue-specific transcription factors and chromatin remodelers function together to ensure gradual, coordinated differentiation of multiple lineages. Here, we define this regulatory interplay in the developing retinal pigmented epithelium (RPE), a neuroectodermal lineage essential for the development, function and maintenance of the adjacent retina. We present a high-resolution spatial transcriptomic atlas of the developing mouse RPE and the adjacent ocular mesenchyme obtained by geographical position sequencing (Geo-seq) of a single developmental stage of the eye that encompasses young and more mature ocular progenitors. These transcriptomic data, available online, reveal the key transcription factors and their gene regulatory networks during RPE and ocular mesenchyme differentiation. Moreover, conditional inactivation followed by Geo-seq revealed that this differentiation program is dependent on the activity of SWI/SNF complexes, shown here to control the expression and activity of RPE transcription factors and, at the same time, inhibit neural progenitor and cell proliferation genes. The findings reveal the roles of the SWI/SNF complexes in controlling the intersection between RPE and neural cell fates and the coupling of cell-cycle exit and differentiation.
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Affiliation(s)
- Shai Ovadia
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Guizhong Cui
- Guangzhou National Laboratory, Department of Basic Research, Guangzhou 510005, China
| | - Ran Elkon
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Mazal Cohen-Gulkar
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Nitay Zuk-Bar
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
| | - Tran Tuoc
- Department of Human Genetics, Ruhr University of Bochum, 44791 Bochum, Germany
| | - Naihe Jing
- Guangzhou National Laboratory, Department of Basic Research, Guangzhou 510005, China
| | - Ruth Ashery-Padan
- Department of Human Molecular Genetics and Biochemistry, Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
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Paşcalău R, Badea TC. Signaling - transcription interactions in mouse retinal ganglion cells early axon pathfinding -a literature review. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1180142. [PMID: 38983012 PMCID: PMC11182120 DOI: 10.3389/fopht.2023.1180142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 04/21/2023] [Indexed: 07/11/2024]
Abstract
Sending an axon out of the eye and into the target brain nuclei is the defining feature of retinal ganglion cells (RGCs). The literature on RGC axon pathfinding is vast, but it focuses mostly on decision making events such as midline crossing at the optic chiasm or retinotopic mapping at the target nuclei. In comparison, the exit of RGC axons out of the eye is much less explored. The first checkpoint on the RGC axons' path is the optic cup - optic stalk junction (OC-OS). OC-OS development and the exit of the RGC pioneer axons out of the eye are coordinated spatially and temporally. By the time the optic nerve head domain is specified, the optic fissure margins are in contact and the fusion process is ongoing, the first RGCs are born in its proximity and send pioneer axons in the optic stalk. RGC differentiation continues in centrifugal waves. Later born RGC axons fasciculate with the more mature axons. Growth cones at the end of the axons respond to guidance cues to adopt a centripetal direction, maintain nerve fiber layer restriction and to leave the optic cup. Although there is extensive information on OC-OS development, we still have important unanswered questions regarding its contribution to the exit of the RGC axons out of the eye. We are still to distinguish the morphogens of the OC-OS from the axon guidance molecules which are expressed in the same place at the same time. The early RGC transcription programs responsible for axon emergence and pathfinding are also unknown. This review summarizes the molecular mechanisms for early RGC axon guidance by contextualizing mouse knock-out studies on OC-OS development with the recent transcriptomic studies on developing RGCs in an attempt to contribute to the understanding of human optic nerve developmental anomalies. The published data summarized here suggests that the developing optic nerve head provides a physical channel (the closing optic fissure) as well as molecular guidance cues for the pioneer RGC axons to exit the eye.
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Affiliation(s)
- Raluca Paşcalău
- Research and Development Institute, Transilvania University of Braşov, Braşov, Romania
- Ophthalmology Clinic, Cluj County Emergency Hospital, Cluj-Napoca, Romania
| | - Tudor Constantin Badea
- Research and Development Institute, Transilvania University of Braşov, Braşov, Romania
- National Center for Brain Research, Institutul de Cercetări pentru Inteligență Artificială, Romanian Academy, Bucharest, Romania
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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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Abstract
Intercellular communication by Wnt proteins governs many essential processes during development, tissue homeostasis and disease in all metazoans. Many context-dependent effects are initiated in the Wnt-producing cells and depend on the export of lipidated Wnt proteins. Although much focus has been on understanding intracellular Wnt signal transduction, the cellular machinery responsible for Wnt secretion became better understood only recently. After lipid modification by the acyl-transferase Porcupine, Wnt proteins bind their dedicated cargo protein Evi/Wntless for transport and secretion. Evi/Wntless and Porcupine are conserved transmembrane proteins, and their 3D structures were recently determined. In this Review, we summarise studies and structural data highlighting how Wnts are transported from the ER to the plasma membrane, and the role of SNX3-retromer during the recycling of its cargo receptor Evi/Wntless. We also describe the regulation of Wnt export through a post-translational mechanism and review the importance of Wnt secretion for organ development and cancer, and as a future biomarker.
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Affiliation(s)
- Lucie Wolf
- German Cancer Research Center (DKFZ), Division of Signalling and Functional Genomics and Heidelberg University, BioQuant and Department of Cell and Molecular Biology, 69120 Heidelberg, Germany
| | - Michael Boutros
- German Cancer Research Center (DKFZ), Division of Signalling and Functional Genomics and Heidelberg University, BioQuant and Department of Cell and Molecular Biology, 69120 Heidelberg, Germany
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7
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Cardozo MJ, Sánchez-Bustamante E, Bovolenta P. Optic cup morphogenesis across species and related inborn human eye defects. Development 2023; 150:dev200399. [PMID: 36714981 PMCID: PMC10110496 DOI: 10.1242/dev.200399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The vertebrate eye is shaped as a cup, a conformation that optimizes vision and is acquired early in development through a process known as optic cup morphogenesis. Imaging living, transparent teleost embryos and mammalian stem cell-derived organoids has provided insights into the rearrangements that eye progenitors undergo to adopt such a shape. Molecular and pharmacological interference with these rearrangements has further identified the underlying molecular machineries and the physical forces involved in this morphogenetic process. In this Review, we summarize the resulting scenarios and proposed models that include common and species-specific events. We further discuss how these studies and those in environmentally adapted blind species may shed light on human inborn eye malformations that result from failures in optic cup morphogenesis, including microphthalmia, anophthalmia and coloboma.
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Affiliation(s)
- Marcos J. Cardozo
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| | - Elena Sánchez-Bustamante
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| | - Paola Bovolenta
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
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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: 36] [Impact Index Per Article: 18.0] [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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Fuhrmann S, Ramirez S, Mina Abouda M, Campbell CD. Porcn is essential for growth and invagination of the mammalian optic cup. Front Cell Dev Biol 2022; 10:1016182. [PMID: 36393832 PMCID: PMC9661423 DOI: 10.3389/fcell.2022.1016182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 10/04/2022] [Indexed: 11/13/2022] Open
Abstract
Microphthalmia, anophthalmia, and coloboma (MAC) are congenital ocular malformations causing 25% of childhood blindness. The X-linked disorder Focal Dermal Hypoplasia (FDH) is frequently associated with MAC and results from mutations in Porcn, a membrane bound O-acyl transferase required for palmitoylation of Wnts to activate multiple Wnt-dependent pathways. Wnt/β-catenin signaling is suppressed in the anterior neural plate for initiation of eye formation and is subsequently required during differentiation of the retinal pigment epithelium (RPE). Non-canonical Wnts are critical for early eye formation in frog and zebrafish. However, it is unclear whether this also applies to mammals. We performed ubiquitous conditional inactivation of Porcn in mouse around the eye field stage. In Porcn CKO , optic vesicles (OV) arrest in growth and fail to form an optic cup. Ventral proliferation is significantly decreased in the mutant OV, with a concomitant increase in apoptotic cell death. While pan-ocular transcription factors such as PAX6, SIX3, LHX2, and PAX2 are present, indicative of maintenance of OV identity, regional expression of VSX2, MITF, OTX2, and NR2F2 is downregulated. Failure of RPE differentiation in Porcn CKO is consistent with downregulation of the Wnt/β-catenin effector LEF1, starting around 2.5 days after inactivation. This suggests that Porcn inactivation affects signaling later than a potential requirement for Wnts to promote eye field formation. Altogether, our data shows a novel requirement for Porcn in regulating growth and morphogenesis of the OV, likely by controlling proliferation and survival. In FDH patients with ocular manifestations, growth deficiency during early ocular morphogenesis may be the underlying cause for microphthalmia.
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Affiliation(s)
- Sabine Fuhrmann
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Cell and Developmental Biology, Vanderbilt University Medical School, Nashville, TN, United States
| | - Sara Ramirez
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
- Department of Cell and Developmental Biology, Vanderbilt University Medical School, Nashville, TN, United States
| | - Mirna Mina Abouda
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Clorissa D. Campbell
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, TN, United States
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Vallée A. Curcumin and Wnt/β‑catenin signaling in exudative age‑related macular degeneration (Review). Int J Mol Med 2022; 49:79. [PMID: 35445729 PMCID: PMC9083851 DOI: 10.3892/ijmm.2022.5135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/11/2022] [Indexed: 11/06/2022] Open
Abstract
Curcumin is a natural product widely used due to its pharmacological effects. Nevertheless, only a limited number of studies concerning the effects of curcumin on exudative age‑related macular degeneration (AMD) is currently available. Since ophthalmic diseases, including exudative AMD, have a marked impact on public health, the prevention and therapy of ophthalmic disorders remain of increasing concern. Exudative AMD is characterized by choroidal neovascularization (CNV) invading the subretinal space, ultimately enhancing exudation and hemorrhaging. The exudative AMD subtype corresponds to 10 to 15% of cases of macular degeneration; however, the occurrence of this subtype has been reported as the major cause of vision loss and blindness, with the occurrence of CNV being responsible for 80% of the cases with vision loss. In CNV increased expression of VEGF has been observed, stimulated by the overactivation of Wnt/β‑catenin signaling pathway. The stimulation of the Wnt/β‑catenin signaling pathway is responsible for the activation of several cellular mechanisms, simultaneously enhancing inflammation, oxidative stress and angiogenesis in numerous diseases, including ophthalmic disorders. Some studies have previously demonstrated the possible advantage of the use of curcumin for the inhibition of Wnt/β‑catenin signaling. In the present review article, the different mechanisms of curcumin are described concerning its effects on oxidative stress, inflammation and angiogenesis in exudative AMD, by interacting with Wnt/β‑catenin signaling.
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Affiliation(s)
- Alexandre Vallée
- Department of Epidemiology-Data-Biostatistics, Delegation of Clinical Research and Innovation (DRCI), Foch Hospital, 92150 Suresnes, France
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11
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Thulabandu V, Ferguson JW, Phung M, Atit RP. EZH2 modulates retinoic acid signaling to ensure myotube formation during development. FEBS Lett 2022; 596:1672-1685. [PMID: 35294045 DOI: 10.1002/1873-3468.14334] [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: 07/26/2021] [Revised: 02/27/2022] [Accepted: 03/02/2022] [Indexed: 11/09/2022]
Abstract
Sequential differentiation of pre-somitic progenitors into myocytes and subsequently into myotubes and myofibers is essential for the myogenic differentiation program (MDP) crucial for muscle development. Signaling factors involved in MDP are Polycomb Repressive Complex 2 (PRC2) targets in various developmental contexts. PRC2 is active in the developing myotomes during MDP, but how it regulates MDP is unclear. Here, we found that myocyte differentiation to myotubes requires Enhancer of Zeste 2 (EZH2), the catalytic component of PRC2. We observed elevated retinoic-acid (RA) signaling in the prospective myocytes in the Ezh2 mutants (E8.5-MusEzh2 ), and its inhibition can partially rescue the myocyte differentiation defect. Together, our data demonstrate a new role for PRC2-EZH2 during myocyte differentiation into myotubes by modulating RA signaling.
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Affiliation(s)
- Venkata Thulabandu
- Dept. of Biology, Case Western Reserve University, Cleveland, Ohio, U.S.A
| | - James W Ferguson
- Dept. of Biology, Case Western Reserve University, Cleveland, Ohio, U.S.A
| | - Melissa Phung
- Dept. of Biology, Case Western Reserve University, Cleveland, Ohio, U.S.A
| | - Radhika P Atit
- Dept. of Biology, Case Western Reserve University, Cleveland, Ohio, U.S.A.,Dept. of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, Ohio, U.S.A.,Dept. of Dermatology, Case Western Reserve University, Cleveland, Ohio, U.S.A
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12
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Balasubramanian R, Min X, Quinn PMJ, Giudice QL, Tao C, Polanco K, Makrides N, Peregrin J, Bouaziz M, Mao Y, Wang Q, da Costa BL, Buenaventura D, Wang F, Ma L, Tsang SH, Fabre PJ, Zhang X. Phase transition specified by a binary code patterns the vertebrate eye cup. SCIENCE ADVANCES 2021; 7:eabj9846. [PMID: 34757798 PMCID: PMC8580326 DOI: 10.1126/sciadv.abj9846] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/21/2021] [Indexed: 05/27/2023]
Abstract
The developing vertebrate eye cup is partitioned into the neural retina (NR), the retinal pigmented epithelium (RPE), and the ciliary margin (CM). By single-cell analysis, we showed that fibroblast growth factor (FGF) signaling regulates the CM in its stem cell–like property of self-renewal, differentiation, and survival, which is balanced by an evolutionarily conserved Wnt signaling gradient. FGF promotes Wnt signaling in the CM by stabilizing β-catenin in a GSK3β-independent manner. While Wnt signaling converts the NR to either the CM or the RPE depending on FGF signaling, FGF transforms the RPE to the NR or CM dependent on Wnt activity. The default fate of the eye cup is the NR, but synergistic FGF and Wnt signaling promotes CM formation both in vivo and in human retinal organoid. Our study reveals that the vertebrate eye develops through phase transition determined by a combinatorial code of FGF and Wnt signaling.
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Affiliation(s)
| | - Xuanyu Min
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | | | - Quentin Lo Giudice
- Department of Basic Neurosciences, University of Geneva, Geneva, Switzerland
| | - Chenqi Tao
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Karina Polanco
- Department of Psychology, Columbia University, New York, NY, USA
| | - Neoklis Makrides
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - John Peregrin
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Michael Bouaziz
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Yingyu Mao
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Qian Wang
- Department of Ophthalmology, Columbia University, New York, NY, USA
| | | | | | - Fen Wang
- Center for Cancer Biology and Nutrition, Institute of Biosciences and Technology, Texas A&M, Houston, TX, USA
| | - Liang Ma
- Division of Dermatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - Stephen H. Tsang
- Department of Ophthalmology, Columbia University, New York, NY, USA
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
- Jonas Children’s Vision Care, and Bernard and Shirley Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Institute of Human Nutrition, Vagelos College of Physicians and Surgeons, Columbia University, New York, NY, USA
- Edward S. Harkness Eye Institute, New York Presbyterian Hospital, Herbert Irving Comprehensive Cancer Center, Columbia University, New York, NY, USA
| | - Pierre J. Fabre
- Department of Basic Neurosciences, University of Geneva, Geneva, Switzerland
| | - Xin Zhang
- Department of Ophthalmology, Columbia University, New York, NY, USA
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY, USA
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13
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Thulabandu V, Nehila T, Ferguson JW, Atit RP. Dermal EZH2 orchestrates dermal differentiation and epidermal proliferation during murine skin development. Dev Biol 2021; 478:25-40. [PMID: 34166654 PMCID: PMC8384472 DOI: 10.1016/j.ydbio.2021.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 05/28/2021] [Accepted: 06/18/2021] [Indexed: 10/21/2022]
Abstract
Skin development and patterning is dependent on factors that regulate the stepwise differentiation of dermal fibroblasts concomitant with dermal-epidermal reciprocal signaling, two processes that are poorly understood. Here we show that dermal EZH2, the methyltransferase enzyme of the epigenetic Polycomb Repressive Complex 2 (PRC2), is a new coordinator of both these processes. Dermal EZH2 activity is present during dermal fibroblast differentiation and is required for spatially restricting Wnt/β-catenin signaling to reinforce dermal fibroblast cell fate. Later in development, dermal EZH2 regulates the expression of reticular dermal markers and initiation of secondary hair follicles. Embryos lacking dermal Ezh2 have elevated epidermal proliferation and differentiation that can be rescued by small molecule inhibition of retinoic acid (RA) signaling. Together, our study reveals that dermal EZH2 is acting like a rheostat to control the levels of Wnt/β-catenin and RA signaling to impact fibroblast differentiation cell autonomously and epidermal keratinocyte development non-cell autonomously, respectively.
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Affiliation(s)
| | - Timothy Nehila
- Dept. of Biology, Case Western Reserve University, Cleveland, OH, USA
| | - James W Ferguson
- Dept. of Biology, Case Western Reserve University, Cleveland, OH, USA
| | - Radhika P Atit
- Dept. of Biology, Case Western Reserve University, Cleveland, OH, USA; Dept. of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA; Dept. of Dermatology, Case Western Reserve University, Cleveland, OH, USA.
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14
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Moreno-Mármol T, Ledesma-Terrón M, Tabanera N, Martin-Bermejo MJ, Cardozo MJ, Cavodeassi F, Bovolenta P. Stretching of the retinal pigment epithelium contributes to zebrafish optic cup morphogenesis. eLife 2021; 10:63396. [PMID: 34545806 PMCID: PMC8530511 DOI: 10.7554/elife.63396] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 09/20/2021] [Indexed: 12/15/2022] Open
Abstract
The vertebrate eye primordium consists of a pseudostratified neuroepithelium, the optic vesicle (OV), in which cells acquire neural retina or retinal pigment epithelium (RPE) fates. As these fates arise, the OV assumes a cup shape, influenced by mechanical forces generated within the neural retina. Whether the RPE passively adapts to retinal changes or actively contributes to OV morphogenesis remains unexplored. We generated a zebrafish Tg(E1-bhlhe40:GFP) line to track RPE morphogenesis and interrogate its participation in OV folding. We show that, in virtual absence of proliferation, RPE cells stretch and flatten, thereby matching the retinal curvature and promoting OV folding. Localized interference with the RPE cytoskeleton disrupts tissue stretching and OV folding. Thus, extreme RPE flattening and accelerated differentiation are efficient solutions adopted by fast-developing species to enable timely optic cup formation. This mechanism differs in amniotes, in which proliferation drives RPE expansion with a much-reduced need of cell flattening. Rounded eyeballs help to optimize vision – but how do they acquire their distinctive shape? In animals with backbones, including humans, the eye begins to form early in development. A single layer of embryonic tissue called the optic vesicle reorganizes itself into a two-layered structure: a thin outer layer of cells, known as the retinal pigmented epithelium (RPE for short), and a thicker inner layer called the neural retina. If this process fails, the animal may be born blind or visually impaired. How this flat two-layered structure becomes round is still being investigated. In fish, studies have shown that the inner cell layer – the neural retina – generates mechanical forces that cause the developing tissue to curve inwards to form a cup-like shape. But it was unclear whether the outer layer of cells (the RPE) also contributed to this process. Moreno-Marmol et al. were able to investigate this question by genetically modifying zebrafish to make all new RPE cells fluoresce. Following the early development of the zebrafish eye under a microscope revealed that RPE cells flattened themselves into long thin structures that stretched to cover the entire neural retina. This change was made possible by the cell’s internal skeleton reorganizing. In fact, preventing this reorganization stopped the RPE cells from flattening, and precluded the optic cup from acquiring its curved shape. The results thus confirmed a direct role for the RPE in generating curvature. The entire process did not require the RPE to produce new cells, allowing the curved shape to emerge in just a few hours. This is a major advantage for fast-developing species such as zebrafish. In species whose embryos develop more slowly, such as mice and humans, the RPE instead grows by producing additional cells – a process that takes many days. The development of the eye thus shows how various species use different evolutionary approaches to achieve a common goal.
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Affiliation(s)
- Tania Moreno-Mármol
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Mario Ledesma-Terrón
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain
| | - Noemi Tabanera
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Maria Jesús Martin-Bermejo
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Marcos J Cardozo
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Florencia Cavodeassi
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Paola Bovolenta
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, c/ Nicolás Cabrera, 1, Campus de la Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Raras (CIBERER), Madrid, Spain
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15
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Latta L, Figueiredo FC, Ashery-Padan R, Collinson JM, Daniels J, Ferrari S, Szentmáry N, Solá S, Shalom-Feuerstein R, Lako M, Xapelli S, Aberdam D, Lagali N. Pathophysiology of aniridia-associated keratopathy: Developmental aspects and unanswered questions. Ocul Surf 2021; 22:245-266. [PMID: 34520870 DOI: 10.1016/j.jtos.2021.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 07/19/2021] [Accepted: 09/08/2021] [Indexed: 12/13/2022]
Abstract
Aniridia, a rare congenital disease, is often characterized by a progressive, pronounced limbal insufficiency and ocular surface pathology termed aniridia-associated keratopathy (AAK). Due to the characteristics of AAK and its bilateral nature, clinical management is challenging and complicated by the multiple coexisting ocular and systemic morbidities in aniridia. Although it is primarily assumed that AAK originates from a congenital limbal stem cell deficiency, in recent years AAK and its pathogenesis has been questioned in the light of new evidence and a refined understanding of ocular development and the biology of limbal stem cells (LSCs) and their niche. Here, by consolidating and comparing the latest clinical and preclinical evidence, we discuss key unanswered questions regarding ocular developmental aspects crucial to AAK. We also highlight hypotheses on the potential role of LSCs and the ocular surface microenvironment in AAK. The insights thus gained lead to a greater appreciation for the role of developmental and cellular processes in the emergence of AAK. They also highlight areas for future research to enable a deeper understanding of aniridia, and thereby the potential to develop new treatments for this rare but blinding ocular surface disease.
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Affiliation(s)
- L Latta
- Dr. Rolf. M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany; Department of Ophthalmology, Saarland University Medical Center, Homburg, Saar, Germany.
| | - F C Figueiredo
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle Upon Tyne, United Kingdom
| | - R Ashery-Padan
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - J M Collinson
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, AB25 2ZD, United Kingdom
| | - J Daniels
- Cells for Sight, UCL Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
| | - S Ferrari
- The Veneto Eye Bank Foundation, Venice, Italy
| | - N Szentmáry
- Dr. Rolf. M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany
| | - S Solá
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - R Shalom-Feuerstein
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of Technology, Haifa, Israel
| | - M Lako
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - S Xapelli
- Instituto Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - D Aberdam
- Centre de Recherche des Cordeliers, INSERM U1138, Team 17, France; Université de Paris, 75006, Paris, France.
| | - N Lagali
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden; Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway.
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16
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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: 21] [Impact Index Per Article: 7.0] [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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17
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Vielle A, Park YK, Secora C, Vergara MN. Organoids for the Study of Retinal Development and Developmental Abnormalities. Front Cell Neurosci 2021; 15:667880. [PMID: 34025363 PMCID: PMC8131530 DOI: 10.3389/fncel.2021.667880] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 04/12/2021] [Indexed: 02/01/2023] Open
Abstract
The cumulative knowledge of retina development has been instrumental in the generation of retinal organoid systems from pluripotent stem cells; and these three-dimensional organoid models, in turn, have provided unprecedented opportunities for retinal research and translational applications, including the ability to model disease in a human setting and to apply these models to the development and validation of therapeutic drugs. In this review article, we examine how retinal organoids can also contribute to our understanding of retinal developmental mechanisms, how this knowledge can be applied to modeling developmental abnormalities, and highlight some of the avenues that remain to be explored.
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Affiliation(s)
- Anne Vielle
- CellSight Ocular Stem Cell and Regeneration Program, Sue Anschutz-Rodgers Eye Center, University of Colorado School of Medicine, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, Aurora, CO, United States
| | - Yuna K Park
- CellSight Ocular Stem Cell and Regeneration Program, Sue Anschutz-Rodgers Eye Center, University of Colorado School of Medicine, Aurora, CO, United States
| | - Conner Secora
- CellSight Ocular Stem Cell and Regeneration Program, Sue Anschutz-Rodgers Eye Center, University of Colorado School of Medicine, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, Aurora, CO, United States.,Master of Science in Modern Human Anatomy Program, Aurora, CO, United States
| | - M Natalia Vergara
- CellSight Ocular Stem Cell and Regeneration Program, Sue Anschutz-Rodgers Eye Center, University of Colorado School of Medicine, Aurora, CO, United States.,Linda Crnic Institute for Down Syndrome, Aurora, CO, United States
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18
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O'Hara-Wright M, Gonzalez-Cordero A. Retinal organoids: a window into human retinal development. Development 2020; 147:147/24/dev189746. [PMID: 33361444 PMCID: PMC7774906 DOI: 10.1242/dev.189746] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Retinal development and maturation are orchestrated by a series of interacting signalling networks that drive the morphogenetic transformation of the anterior developing brain. Studies in model organisms continue to elucidate these complex series of events. However, the human retina shows many differences from that of other organisms and the investigation of human eye development now benefits from stem cell-derived organoids. Retinal differentiation methods have progressed from simple 2D adherent cultures to self-organising micro-physiological systems. As models of development, these have collectively offered new insights into the previously unexplored early development of the human retina and informed our knowledge of the key cell fate decisions that govern the specification of light-sensitive photoreceptors. Although the developmental trajectories of other retinal cell types remain more elusive, the collation of omics datasets, combined with advanced culture methodology, will enable modelling of the intricate process of human retinogenesis and retinal disease in vitro. Summary: Retinal organoid systems derived from human pluripotent stem cells are micro-physiological systems that offer new insights into previously unexplored human retina development.
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Affiliation(s)
- Michelle O'Hara-Wright
- Stem Cell Medicine Group, Children's Medical Research Institute, University of Sydney, Westmead, 2145, NSW, Australia.,School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
| | - Anai Gonzalez-Cordero
- Stem Cell Medicine Group, Children's Medical Research Institute, University of Sydney, Westmead, 2145, NSW, Australia .,School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Westmead, 2145, NSW, Australia
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19
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Najarro EH, Huang J, Jacobo A, Quiruz LA, Grillet N, Cheng AG. Dual regulation of planar polarization by secreted Wnts and Vangl2 in the developing mouse cochlea. Development 2020; 147:dev.191981. [PMID: 32907846 DOI: 10.1242/dev.191981] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 08/24/2020] [Indexed: 12/14/2022]
Abstract
Planar cell polarity (PCP) proteins localize asymmetrically to instruct cell polarity within the tissue plane, with defects leading to deformities of the limbs, neural tube and inner ear. Wnt proteins are evolutionarily conserved polarity cues, yet Wnt mutants display variable PCP defects; thus, how Wnts regulate PCP remains unresolved. Here, we have used the developing cochlea as a model system to show that secreted Wnts regulate PCP through polarizing a specific subset of PCP proteins. Conditional deletion of Wntless or porcupine, both of which are essential for secretion of Wnts, caused misrotated sensory cells and shortened cochlea - both hallmarks of PCP defects. Wntless-deficient cochleae lacked the polarized PCP components dishevelled 1/2 and frizzled 3/6, while other PCP proteins (Vangl1/2, Celsr1 and dishevelled 3) remained localized. We identified seven Wnt paralogues, including the major PCP regulator Wnt5a, which was, surprisingly, dispensable for planar polarization in the cochlea. Finally, Vangl2 haploinsufficiency markedly accentuated sensory cell polarization defects in Wntless-deficient cochlea. Together, our study indicates that secreted Wnts and Vangl2 coordinate to ensure proper tissue polarization during development.
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Affiliation(s)
- Elvis Huarcaya Najarro
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jennifer Huang
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Adrian Jacobo
- Laboratory of Sensory Neuroscience, The Rockefeller University, New York, NY 10065, USA
| | - Lee A Quiruz
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Nicolas Grillet
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alan G Cheng
- Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA 94305, USA
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20
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Medina-Martinez O, Haller M, Rosenfeld JA, O'Neill MA, Lamb DJ, Jamrich M. The transcription factor Maz is essential for normal eye development. Dis Model Mech 2020; 13:dmm044412. [PMID: 32571845 PMCID: PMC7449797 DOI: 10.1242/dmm.044412] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 06/10/2020] [Indexed: 12/19/2022] Open
Abstract
Wnt/β-catenin signaling has an essential role in eye development. Faulty regulation of this pathway results in ocular malformations, owing to defects in cell-fate determination and differentiation. Herein, we show that disruption of Maz, the gene encoding Myc-associated zinc-finger transcription factor, produces developmental eye defects in mice and humans. Expression of key genes involved in the Wnt cascade, Sfrp2, Wnt2b and Fzd4, was significantly increased in mice with targeted inactivation of Maz, resulting in abnormal peripheral eye formation with reduced proliferation of the progenitor cells in the region. Paradoxically, the Wnt reporter TCF-Lef1 displayed a significant downregulation in Maz-deficient eyes. Molecular analysis indicates that Maz is necessary for the activation of the Wnt/β-catenin pathway and participates in the network controlling ciliary margin patterning. Copy-number variations and single-nucleotide variants of MAZ were identified in humans that result in abnormal ocular development. The data support MAZ as a key contributor to the eye comorbidities associated with chromosome 16p11.2 copy-number variants and as a transcriptional regulator of ocular development.
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Affiliation(s)
- Olga Medina-Martinez
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Meade Haller
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
- Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jill A Rosenfeld
- Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Baylor Genetics Laboratories, Houston, TX 77021, USA
| | - Marisol A O'Neill
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
- Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX 77030, USA
| | - Dolores J Lamb
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
- Center for Reproductive Medicine, Baylor College of Medicine, Houston, TX 77030, USA
- James Buchanan Brady Foundation Department of Urology, Weill Cornell Medical College, New York City, NY 10065, USA
- Englander Institute for Precision Medicine, Weill Cornell Medical College, New York City, NY 10065, USA
- Center for Reproductive Genomics, Weill Cornell Medical College, New York City, NY 10065, USA
| | - Milan Jamrich
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
- Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
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21
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Zhang S, Kim B, Zhu X, Gui X, Wang Y, Lan Z, Prabhu P, Fond K, Wang A, Guo F. Glial type specific regulation of CNS angiogenesis by HIFα-activated different signaling pathways. Nat Commun 2020; 11:2027. [PMID: 32332719 PMCID: PMC7181614 DOI: 10.1038/s41467-020-15656-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 03/12/2020] [Indexed: 01/13/2023] Open
Abstract
The mechanisms by which oligodendroglia modulate CNS angiogenesis remain elusive. Previous in vitro data suggest that oligodendroglia regulate CNS endothelial cell proliferation and blood vessel formation through hypoxia inducible factor alpha (HIFα)-activated Wnt (but not VEGF) signaling. Using in vivo genetic models, we show that HIFα in oligodendroglia is necessary and sufficient for angiogenesis independent of CNS regions. At the molecular level, HIFα stabilization in oligodendroglia does not perturb Wnt signaling but rather activates VEGF. At the functional level, genetically blocking oligodendroglia-derived VEGF but not Wnt significantly decreases oligodendroglial HIFα-regulated CNS angiogenesis. Blocking astroglia-derived Wnt signaling reduces astroglial HIFα-regulated CNS angiogenesis. Together, our in vivo data demonstrate that oligodendroglial HIFα regulates CNS angiogenesis through Wnt-independent and VEGF-dependent signaling. These findings suggest an alternative mechanistic understanding of CNS angiogenesis by postnatal glial cells and unveil a glial cell type-dependent HIFα-Wnt axis in regulating CNS vessel formation. In the central nervous system, the maturation of glial cells is temporally and functionally coupled with that of the vascular network during postnatal development. Here the authors show that oligodendroglial HIFα regulates CNS angiogenesis through Wnt-independent and VEGF-dependent signaling, while astroglial HIFα participates through Wnt-dependent signaling.
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Affiliation(s)
- Sheng Zhang
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA.,Department of Neurology, School of Medicine, UC Davis, Sacramento, CA, 95817, USA
| | - Bokyung Kim
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA.,Department of Neurology, School of Medicine, UC Davis, Sacramento, CA, 95817, USA
| | - Xiaoqing Zhu
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA.,Qingdao University, Qingdao, China
| | - Xuehong Gui
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA
| | - Yan Wang
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA.,Department of Neurology, School of Medicine, UC Davis, Sacramento, CA, 95817, USA
| | - Zhaohui Lan
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA.,Department of Neurology, School of Medicine, UC Davis, Sacramento, CA, 95817, USA
| | - Preeti Prabhu
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA
| | - Kenneth Fond
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA
| | - Aijun Wang
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA.,Department of Surgery, School of Medicine, UC Davis, Sacramento, CA, 95817, USA
| | - Fuzheng Guo
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children/UC Davis School of Medicine, Sacramento, CA, 95817, USA. .,Department of Neurology, School of Medicine, UC Davis, Sacramento, CA, 95817, USA.
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22
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Vallée A, Vallée JN, Guillevin R, Lecarpentier Y. Riluzole: a therapeutic strategy in Alzheimer's disease by targeting the WNT/β-catenin pathway. Aging (Albany NY) 2020; 12:3095-3113. [PMID: 32035419 PMCID: PMC7041777 DOI: 10.18632/aging.102830] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 01/27/2020] [Indexed: 12/17/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease, where the etiology remains unclear. AD is characterized by amyloid-(Aβ) protein aggregation and neurofibrillary plaques deposits. Oxidative stress and chronic inflammation have been suggested as causes of AD. Glutamatergic pathway dysregulation is also mainly associated with AD process. In AD, the canonical WNT/β-catenin pathway is downregulated. Downregulation of WNT/β-catenin, by activation of GSK-3β-induced Aβ, and inactivation of PI3K/Akt pathway involve oxidative stress in AD. The downregulation of the WNT/β-catenin pathway decreases the activity of EAAT2, the glutamate receptors, and leads to neuronal death. In AD, oxidative stress, neuroinflammation and glutamatergic pathway operate in a vicious circle driven by the dysregulation of the WNT/β-catenin pathway. Riluzole is a glutamate modulator and used as treatment in amyotrophic lateral sclerosis. Recent findings have highlighted its use in AD and its potential increase power on the WNT pathway. Nevertheless, the mechanism by which Riluzole can operate in AD remains unclear and should be better determine. The focus of our review is to highlight the potential action of Riluzole in AD by targeting the canonical WNT/β-catenin pathway to modulate glutamatergic pathway, oxidative stress and neuroinflammation.
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Affiliation(s)
- Alexandre Vallée
- DACTIM-MIS, Laboratory of Mathematics and Applications (LMA), University of Poitiers, CHU de Poitiers, Poitiers, France
| | - Jean-Noël Vallée
- CHU Amiens Picardie, University of Picardie Jules Verne (UPJV), Amiens, France.,Laboratory of Mathematics and Applications (LMA), University of Poitiers, Poitiers, France
| | - Rémy Guillevin
- DACTIM-MIS, Laboratory of Mathematics and Applications (LMA), University of Poitiers, CHU de Poitiers, Poitiers, France
| | - Yves Lecarpentier
- Centre de Recherche Clinique, Grand Hôpital de l'Est Francilien (GHEF), Meaux, France
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23
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Vallée A, Lecarpentier Y, Vallée R, Guillevin R, Vallée JN. Circadian Rhythms in Exudative Age-Related Macular Degeneration: The Key Role of the Canonical WNT/β-Catenin Pathway. Int J Mol Sci 2020; 21:ijms21030820. [PMID: 32012797 PMCID: PMC7037737 DOI: 10.3390/ijms21030820] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 01/23/2020] [Accepted: 01/27/2020] [Indexed: 02/07/2023] Open
Abstract
Age-related macular degeneration (AMD) is considered as the main worldwide cause of blindness in elderly adults. Exudative AMD type represents 10 to 15% of macular degeneration cases, but is the main cause of vision loss and blindness. Circadian rhythm changes are associated with aging and could further accelerate it. However, the link between circadian rhythms and exudative AMD is not fully understood. Some evidence suggests that dysregulation of circadian functions could be manifestations of diseases or could be risk factors for the development of disease in elderly adults. Biological rhythms are complex systems interacting with the environment and control several physiological pathways. Recent findings have shown that the dysregulation of circadian rhythms is correlated with exudative AMD. One of the main pathways involved in exudative AMD is the canonical WNT/β-catenin pathway. Circadian clocks have a main role in some tissues by driving the circadian expression of genes involved in physiological and metabolic functions. In exudative AMD, the increase of the canonical WNT/β-catenin pathway is enhanced by the dysregulation of circadian rhythms. Exudative AMD progression is associated with major metabolic reprogramming, initiated by aberrant WNT/β-catenin pathway, of aerobic glycolysis. This review focuses on the interest of circadian rhythm dysregulation in exudative AMD through the aberrant upregulation of the canonical WNT/β-catenin pathway.
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Affiliation(s)
- Alexandre Vallée
- DACTIM-MIS, Laboratory of Mathematics and Applications (LMA), UMR CNRS 7348, University of Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - Yves Lecarpentier
- Centre de Recherche Clinique, Grand Hôpital de l'Est Francilien (GHEF), 77100 Meaux, France
| | - Rodolphe Vallée
- University Hospital Group of Paris-Seine-Saint-Denis, APHP, University of Paris-13 Sorbonne Paris-Cité, 93000 Paris, France
| | - Rémy Guillevin
- DACTIM-MIS, Laboratory of Mathematics and Applications (LMA), UMR CNRS 7348, University of Poitiers, CHU de Poitiers, 86021 Poitiers, France
| | - Jean-Noël Vallée
- CHU Amiens Picardie, University of Picardie Jules Verne (UPJV), 80000 Amiens, France
- Laboratory of Mathematics and Applications (LMA), UMR CNRS 7348, University of Poitiers, 86021 Poitiers, France
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24
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Valensi M, Goldman G, Marchant D, Van Den Berghe L, Jonet L, Daruich A, Robert MP, Krejci E, Klein C, Mascarelli F, Versaux-Botteri C, Moulin A, Putterman M, Guimiot F, Molina T, Terris B, Brémond-Gignac D, Behar-Cohen F, Abitbol MM. Sostdc1 is expressed in all major compartments of developing and adult mammalian eyes. Graefes Arch Clin Exp Ophthalmol 2019; 257:2401-2427. [PMID: 31529323 DOI: 10.1007/s00417-019-04462-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 08/20/2019] [Accepted: 09/04/2019] [Indexed: 01/16/2023] Open
Abstract
PURPOSE This study was conducted in order to study Sostdc1 expression in rat and human developing and adult eyes. METHODS Using the yeast signal sequence trap screening method, we identified the Sostdc1 cDNA encoding a protein secreted by the adult rat retinal pigment epithelium. We determined by in situ hybridization, RT-PCR, immunohistochemistry, and western blot analysis Sostdc1 gene and protein expression in developing and postnatal rat ocular tissue sections. We also investigated Sostdc1 immunohistolocalization in developing and adult human ocular tissues. RESULTS We demonstrated a prominent Sostdc1 gene expression in the developing rat central nervous system (CNS) and eyes at early developmental stages from E10.5 days postconception (dpc) to E13 dpc. Specific Sostdc1 immunostaining was also detected in most adult cells of rat ocular tissue sections. We also identified the rat ocular embryonic compartments characterized by a specific Sostdc1 immunohistostaining and specific Pax6, Sox2, Otx2, and Vsx2 immunohistostaining from embryonic stages E10.5 to E13 dpc. Furthermore, we determined the localization of SOSTDC1 immunoreactivity in ocular tissue sections of developing and adult human eyes. Indeed, we detected SOSTDC1 immunostaining in developing and adult human retinal pigment epithelium (RPE) and neural retina (NR) as well as in several developing and adult human ocular compartments, including the walls of choroidal and scleral vessels. Of utmost importance, we observed a strong SOSTDC1 expression in a pathological ocular specimen of type 2 Peters' anomaly complicated by retinal neovascularization as well in the walls ofother pathological extra-ocular vessels. CONCLUSION: As rat Sostdc1 and human SOSTDC1 are dual antagonists of the Wnt/β-catenin and BMP signaling pathways, these results underscore the potential crucial roles of these pathways and their antagonists, such as Sostdc1 and SOSTDC1, in developing and adult mammalian normal eyes as well as in syndromic and nonsyndromic congenital eye diseases.
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Affiliation(s)
- Maud Valensi
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
| | - Gabrielle Goldman
- APHP, Service de Pathologie de L'Hôpital Cochin-Hôtel-Dieu, Université Paris Descartes, 27 rue du Faubourg Saint-Jacques, 75014, Paris, France
| | - Dominique Marchant
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
- Sorbonne Paris Cité, UFR SMBH, Laboratoire Hypoxie et poumons, Université Paris 13, EA 2363, 93017, Bobigny, France
| | - Loïc Van Den Berghe
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
- Inserm UMR 1037, CRCT (Cancer Research Center of Toulouse), 31037, Toulouse, France
| | - Laurent Jonet
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
| | - Alejandra Daruich
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
- AP-HP, Hôpital Universitaire Necker-Enfants-Malades, Service d'Ophtalmologie, 149 rue de Sèvres, 75015, Paris, France
| | - Matthieu P Robert
- AP-HP, Hôpital Universitaire Necker-Enfants-Malades, Service d'Ophtalmologie, 149 rue de Sèvres, 75015, Paris, France
- COGnition and Action Group, UMR 8257, CNRS, Université Paris Descartes, Paris, France
| | - Eric Krejci
- COGnition and Action Group, UMR 8257, CNRS, Université Paris Descartes, Paris, France
| | - Christophe Klein
- Centre d'Imagerie Cellulaire et de Cytométrie (CICC), Centre de Recherche des Cordeliers (CRC), Université Pierre et Marie Curie - Paris 6, Université Paris Descartes - Paris 5, UMR_S 1138, 75006, Paris, France
| | - Frédéric Mascarelli
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
| | - Claudine Versaux-Botteri
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
| | - Alexandre Moulin
- Département de Pathologie, Hôpital Ophtalmique Jules-Gonin , 15, avenue de France, 1004, Lausanne, Switzerland
| | - Marc Putterman
- APHP, Service de Pathologie de l'Hôpital Universitaire Necker-Enfants-Malades, Université Paris Descartes, 149 rue de Sèvres, 75015, Paris, France
| | - Fabien Guimiot
- Unité Fonctionnelle de Foeto-Pathologie, Hôpital Universitaire Robert Debré, 48 Boulevard Serrurier, 75019, Paris, France
| | - Thierry Molina
- APHP, Service de Pathologie de l'Hôpital Universitaire Necker-Enfants-Malades, Université Paris Descartes, 149 rue de Sèvres, 75015, Paris, France
| | - Benoît Terris
- APHP, Service de Pathologie de L'Hôpital Cochin-Hôtel-Dieu, Université Paris Descartes, 27 rue du Faubourg Saint-Jacques, 75014, Paris, France
| | - Dominique Brémond-Gignac
- AP-HP, Hôpital Universitaire Necker-Enfants-Malades, Service d'Ophtalmologie, 149 rue de Sèvres, 75015, Paris, France
| | - Francine Behar-Cohen
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France
- AP-HP, Service d'Ophtalmologie, Hôpital Universitaire Cochin-Hôtel-Dieu, 27 rue du Faubourg Saint-Jacques, 75014, Paris, France
| | - Marc M Abitbol
- Centre de Recherches des Cordeliers, UMR_S INSERM 1138, Equipe 17, Université Paris Descartes, 15 rue de l'école de médecine, 75006, Paris, France.
- AP-HP, Hôpital Universitaire Necker-Enfants-Malades, Service d'Ophtalmologie, 149 rue de Sèvres, 75015, Paris, France.
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Cardozo MJ, Almuedo-Castillo M, Bovolenta P. Patterning the Vertebrate Retina with Morphogenetic Signaling Pathways. Neuroscientist 2019; 26:185-196. [PMID: 31509088 DOI: 10.1177/1073858419874016] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The primordium of the vertebrate eye is composed of a pseudostratified and apparently homogeneous neuroepithelium, which folds inward to generate a bilayered optic cup. During these early morphogenetic events, the optic vesicle is patterned along three different axes-proximo-distal, dorso-ventral, and naso-temporal-and three major domains: the neural retina, the retinal pigment epithelium (RPE), and the optic stalk. These fundamental steps that enable the subsequent development of a functional eye, entail the precise coordination among genetic programs. These programs are driven by the interplay of signaling pathways and transcription factors, which progressively dictate how each tissue should evolve. Here, we discuss the contribution of the Hh, Wnt, FGF, and BMP signaling pathways to the early patterning of the retina. Comparative studies in different vertebrate species have shown that their morphogenetic activity is repetitively used to orchestrate the progressive specification of the eye with evolutionary conserved mechanisms that have been adapted to match the specific need of a given species.
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Affiliation(s)
- Marcos J Cardozo
- Centro de Biología Molecular "Severo Ochoa," (CSIC/UAM), Madrid, Spain.,CIBERER, ISCIII, Madrid, Spain
| | | | - Paola Bovolenta
- Centro de Biología Molecular "Severo Ochoa," (CSIC/UAM), Madrid, Spain.,CIBERER, ISCIII, Madrid, Spain
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26
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Cavodeassi F, Wilson SW. Looking to the future of zebrafish as a model to understand the genetic basis of eye disease. Hum Genet 2019; 138:993-1000. [PMID: 31422478 PMCID: PMC6710215 DOI: 10.1007/s00439-019-02055-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 07/31/2019] [Indexed: 02/07/2023]
Abstract
In this brief commentary, we provide some of our thoughts and opinions on the current and future use of zebrafish to model human eye disease, dissect pathological progression and advance in our understanding of the genetic bases of microphthalmia, andophthalmia and coloboma (MAC) in humans. We provide some background on eye formation in fish and conservation and divergence across vertebrates in this process, discuss different approaches for manipulating gene function and speculate on future research areas where we think research using fish may prove to be particularly effective.
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Affiliation(s)
- Florencia Cavodeassi
- Institute of Medical and Biomedical Education, St. George's, University of London, Cranmer Terrace, London, SW17 0RE, UK.
| | - Stephen W Wilson
- Department of Cell and Developmental Biology, Biosciences, UCL, Gower St, London, WC1E 6BT, UK
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27
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Zhang R, Kikuchi AT, Nakao T, Russell JO, Preziosi ME, Poddar M, Singh S, Bell AW, England SG, Monga SP. Elimination of Wnt Secretion From Stellate Cells Is Dispensable for Zonation and Development of Liver Fibrosis Following Hepatobiliary Injury. Gene Expr 2019; 19:121-136. [PMID: 30236172 PMCID: PMC6466178 DOI: 10.3727/105221618x15373858350141] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Alterations in the Wnt signaling pathway including those impacting hepatic stellate cells (HSCs) have been implicated in liver fibrosis. In the current study, we first examined the expression of Wnt genes in human HSC (HHSCs) after treatment with a profibrogenic factor TGF-β1. Next, we generated HSC-specific Wntless (Wls) knockout (KO) using the Lrat-cre and Wls-floxed mice. KO and littermate controls (CON) were characterized for any basal phenotype and subjected to two liver fibrosis protocols. In vitro, TGF-β1 induced expression of Wnt2, 5a and 9a while decreasing Wnt2b, 3a, 4, and 11 in HHSC. In vivo, KO and CON mice were born at normal Mendelian ratio and lacked any overt phenotype. Loss of Wnt secretion from HSCs had no effect on liver weight and did not impact β-catenin activation in the pericentral hepatocytes. After 7 days of bile duct ligation (BDL), KO and CON showed comparable levels of serum alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, total and direct bilirubin. Comparable histology, Sirius red staining, and immunohistochemistry for α-SMA, desmin, Ki-67, F4/80, and CD45 indicated similar proliferation, inflammation, and portal fibrosis in both groups. Biweekly administration of carbon tetrachloride for 4 or 8 weeks also led to comparable serum biochemistry, inflammation, and fibrosis in KO and CON. Specific Wnt genes were altered in HHSCs in response to TGF-β1; however, eliminating Wnt secretion from HSC did not impact basal β-catenin activation in normal liver nor did it alter the injury-repair response during development of liver fibrosis.
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Affiliation(s)
- Rong Zhang
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Alexander T Kikuchi
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Toshimasa Nakao
- Department of Organ Transplantation and General Surgery, Graduate School of Medical Sciences, Kyoto Prefectural University of Medical School, Hirokoji, Kawaramachi, Kamikyo-ku, Kyoto City, Kyoto, Japan
| | - Jacquelyn O Russell
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Morgan E Preziosi
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Minakshi Poddar
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Sucha Singh
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Aaron W Bell
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Steven G England
- Future Therapeutics and Technologies, Abbvie, North Chicago, IL, USA
| | - Satdarshan P Monga
- Department of Pathology, University of Pittsburgh, School of Medicine and University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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28
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Abstract
This chapter provides an overview of the early developmental origins of six ocular tissues: the cornea, lens, ciliary body, iris, neural retina, and retina pigment epithelium. Many of these tissue types are concurrently specified and undergo a complex set of morphogenetic movements that facilitate their structural interconnection. Within the context of vertebrate eye organogenesis, we also discuss the genetic hierarchies of transcription factors and signaling pathways that regulate growth, patterning, cell type specification and differentiation.
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Affiliation(s)
- Joel B Miesfeld
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, Davis, CA, United States
| | - Nadean L Brown
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, Davis, CA, United States.
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29
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Moreno-Marmol T, Cavodeassi F, Bovolenta P. Setting Eyes on the Retinal Pigment Epithelium. Front Cell Dev Biol 2018; 6:145. [PMID: 30406103 PMCID: PMC6207792 DOI: 10.3389/fcell.2018.00145] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 10/08/2018] [Indexed: 01/08/2023] Open
Abstract
The neural component of the zebrafish eye derives from a small group of cells known as the eye/retinal field. These cells, positioned in the anterior neural plate, rearrange extensively and generate the optic vesicles (OVs). Each vesicle subsequently folds over itself to form the double-layered optic cup, from which the mature eye derives. During this transition, cells of the OV are progressively specified toward three different fates: the retinal pigment epithelium (RPE), the neural retina, and the optic stalk. Recent studies have shown that folding of the zebrafish OV into a cup is in part driven by basal constriction of the cells of the future neural retina. During folding, however, RPE cells undergo an even more dramatic shape conversion that seems to entail the acquisition of unique properties. How these changes occur and whether they contribute to optic cup formation is still poorly understood. Here we will review present knowledge on RPE morphogenesis and discuss potential mechanisms that may explain such transformation using examples taken from embryonic Drosophila tissues that undergo similar shape changes. We will also put forward a hypothesis for optic cup folding that considers an active contribution from the RPE.
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Affiliation(s)
- Tania Moreno-Marmol
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
| | - Florencia Cavodeassi
- Institute of Medical and Biomedical Education, University of London, London, United Kingdom
| | - Paola Bovolenta
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas, Universidad Autónoma de Madrid, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
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30
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Seo J, Kee HJ, Choi HJ, Lee JE, Park SY, Lee SH, Jeong MH, Guk G, Lee S, Choi KC, Choi YY, Kim H, Noh SH, Yoon HG, Cheong JH. Inhibition of Wntless/GPR177 suppresses gastric tumorigenesis. BMB Rep 2018; 51:255-260. [PMID: 29555015 PMCID: PMC5988581 DOI: 10.5483/bmbrep.2018.51.5.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Indexed: 12/23/2022] Open
Abstract
Wntless/GPR177 functions as WNT ligand carrier protein and activator of WNT/β-catenin signaling, however, its molecular role in gastric cancer (GC) has remained elusive. We investigated the role of GPR177 in gastric tumorigenesis and provided the therapeutic potential of a clinical development of anti-GPR177 monoclonal antibodies. GPR177 mRNA expression was assessed in GC transcriptome data sets (GSE15459, n = 184; GSE66229, n = 300); protein expression was assessed in independent patient tumor tissues (Yonsei TMA, n = 909). GPR177 expression were associated with unfavorable prognosis [log-rank test, GSE15459 (P = 0.00736), GSE66229 (P = 0.0142), and Yonsei TMA (P = 0.0334)] and identified as an independent risk predictor of clinical outcomes: GSE15459 [hazard ratio (HR) 1.731 (95% confidence interval; CI; 1.103–2.715), P = 0.017], GSE66229 [HR 1.54 (95% CI, 1.10–2.151), P = 0.011], and Yonsei TMA [HR 1.254 (95% CI, 1.049–1.500), P = 0.013]. Either antibody treatment or GPR177 knockdown suppressed proliferation of GC cells and sensitized cells to apoptosis. And also inhibition of GPR177 suppresses in vitro and in vivo tumorogenesis in GC cells and inhibits WNT/β-catenin signaling. Finally, targeting and inhibition of GPR177 with antibody suppressed tumorigenesis in PDX model. Together, these results suggest GPR177 as a novel candidate for prognostic marker as well as a promising target for treatment of GC patients.
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Affiliation(s)
- Jaesung Seo
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Hyun Jung Kee
- Department of Surgery, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Hye Ji Choi
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea; Department of Surgery, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Jae Eun Lee
- Department of Surgery, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Soo-Yeon Park
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Seung-Hyun Lee
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Mi-Hyeon Jeong
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Garam Guk
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - SooYeon Lee
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Kyung-Chul Choi
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 05505, Korea
| | - Yoon Young Choi
- Department of Surgery, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Hyunki Kim
- Department of Pathology, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Sung Hoon Noh
- Department of Surgery, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Ho-Geun Yoon
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Jae-Ho Cheong
- Department of Biochemistry and Molecular Biology, Brain Korea 21 PLUS Project for Medical Sciences, Yonsei University College of Medicine, Seoul 03722, Korea; Department of Surgery, Yonsei University College of Medicine, Seoul 03722, Korea
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31
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Luo Z, Zhong X, Li K, Xie B, Liu Y, Ye M, Li K, Xu C, Ge J. An Optimized System for Effective Derivation of Three-Dimensional Retinal Tissue via Wnt Signaling Regulation. Stem Cells 2018; 36:1709-1722. [DOI: 10.1002/stem.2890] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 06/17/2018] [Accepted: 06/25/2018] [Indexed: 01/04/2023]
Affiliation(s)
- Ziming Luo
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Xiufeng Zhong
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Kaijing Li
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Bingbing Xie
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Yuchun Liu
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Meifang Ye
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Kang Li
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Chaochao Xu
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
| | - Jian Ge
- State Key Laboratory of Ophthalmology, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Zhongshan Ophthalmic Center; Sun Yat-sen University; Guangzhou Guangdong People's Republic of China
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32
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The peripheral eye: A neurogenic area with potential to treat retinal pathologies? Prog Retin Eye Res 2018; 68:110-123. [PMID: 30201383 DOI: 10.1016/j.preteyeres.2018.09.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 08/31/2018] [Accepted: 09/03/2018] [Indexed: 12/14/2022]
Abstract
Numerous degenerative diseases affecting visual function, including glaucoma and retinitis pigmentosa, are produced by the loss of different types of retinal cells. Cell replacement therapy has emerged as a promising strategy for treating these and other retinal diseases. The retinal margin or ciliary body (CB) of mammals has been proposed as a potential source of cells to be used in degenerative conditions affecting the retina because it has been reported it might hold neurogenic potential beyond embryonic development. However, many aspects of the origin and biology of the CB are unknown and more recent experiments have challenged the capacity of CB cells to generate different types of retinal neurons. Here we review the most recent findings about the development of the marginal zone of the retina in different vertebrates and some of the mechanisms underlying the proliferative and neurogenic capacity of this fascinating region of the vertebrates eye. In addition, we performed experiments to isolate CB cells from the mouse retina, generated neurospheres and observed that they can be expanded with a proliferative ratio similar to neural stem cells. When induced to differentiate, cells derived from the CB neurospheres start to express early neural markers but, unlike embryonic stem cells, they are not able to fully differentiate in vitro or generate retinal organoids. Together with previous reports on the neurogenic capacity of CB cells, also reviewed here, our results contribute to the current knowledge about the potentiality of this peripheral region of the eye as a therapeutic source of functional retinal neurons in degenerative diseases.
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33
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Cohen-Tayar Y, Cohen H, Mitiagin Y, Abravanel Z, Levy C, Idelson M, Reubinoff B, Itzkovitz S, Raviv S, Kaestner KH, Blinder P, Elkon R, Ashery-Padan R. Pax6 regulation of Sox9 in the mouse retinal pigmented epithelium controls its timely differentiation and choroid vasculature development. Development 2018; 145:dev.163691. [PMID: 29986868 DOI: 10.1242/dev.163691] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 07/02/2018] [Indexed: 01/08/2023]
Abstract
The synchronized differentiation of neuronal and vascular tissues is crucial for normal organ development and function, although there is limited information about the mechanisms regulating the coordinated development of these tissues. The choroid vasculature of the eye serves as the main blood supply to the metabolically active photoreceptors, and develops together with the retinal pigmented epithelium (RPE). Here, we describe a novel regulatory relationship between the RPE transcription factors Pax6 and Sox9 that controls the timing of RPE differentiation and the adjacent choroid maturation. We used a novel machine learning algorithm tool to analyze high resolution imaging of the choroid in Pax6 and Sox9 conditional mutant mice. Additional unbiased transcriptomic analyses in mutant mice and RPE cells generated from human embryonic stem cells, as well as chromatin immunoprecipitation and high-throughput analyses, revealed secreted factors that are regulated by Pax6 and Sox9. These factors might be involved in choroid development and in the pathogenesis of the common blinding disease: age-related macular degeneration (AMD).
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Affiliation(s)
- Yamit Cohen-Tayar
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Hadar Cohen
- Department of Particle Physics, Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Yulia Mitiagin
- Department of Neurobiology, Biochemistry and Biophysics school, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Zohar Abravanel
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Carmit Levy
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Masha Idelson
- The Hadassah Human Embryonic Stem Cell Research Center, The Goldyne Savad Institute of Gene Therapy and The Department of Obstetrics and Gynecology, Hadassah-Hebrew University Medical Center, 9112001 Jerusalem, Israel
| | - Benjamin Reubinoff
- The Hadassah Human Embryonic Stem Cell Research Center, The Goldyne Savad Institute of Gene Therapy and The Department of Obstetrics and Gynecology, Hadassah-Hebrew University Medical Center, 9112001 Jerusalem, Israel
| | - Shalev Itzkovitz
- Department of Molecular Cell Biology, Weizmann Institute of Science 76100, Rehovot, Israel
| | - Shaul Raviv
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Klaus H Kaestner
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, 12-126 Smilow Center for Translational Research, 3400 Civic Center Blvd, Philadelphia, PA 19104-6145, USA
| | - Pablo Blinder
- Department of Neurobiology, Biochemistry and Biophysics school, George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv 69978, Israel.,Sagol School for Neuroscience, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Ran Elkon
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv 69978, Israel .,Sagol School for Neuroscience, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Ruth Ashery-Padan
- Department of Human Molecular Genetics and Biochemistry, Sackler Faculty of Medicine, Sagol School of Neurosciences, Tel Aviv University, Tel Aviv 69978, Israel .,Sagol School for Neuroscience, Tel-Aviv University, Tel Aviv 69978, Israel
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34
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Wang Y, Mahesh P, Wang Y, Novo SG, Shihan MH, Hayward-Piatkovskyi B, Duncan MK. Spatiotemporal dynamics of canonical Wnt signaling during embryonic eye development and posterior capsular opacification (PCO). Exp Eye Res 2018; 175:148-158. [PMID: 29932883 DOI: 10.1016/j.exer.2018.06.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 06/14/2018] [Accepted: 06/18/2018] [Indexed: 02/07/2023]
Abstract
The appropriate spatial and temporal regulation of canonical Wnt signaling is vital for eye development. However, the literature often conflicts on the distribution of canonical Wnt signaling in the eye. Here, using a sensitive mouse transgenic reporter line, we report a detailed re-evaluation of the spatiotemporal dynamics of canonical Wnt signaling in the developing eye. Canonical Wnt activity was dynamic in the optic vesicle and later in the retina, while it was absent from the ectodermal precursors of the lens and corneal epithelium. However, later in corneal development, canonical Wnt reporter activity was detected in corneal stroma and endothelium precursors as they form from the neural crest, although this was lost around birth. Interestingly, while no canonical Wnt signaling was detected in the corneal limbus or basal cells at any developmental stage, it was robust in adult corneal wing and squamous epithelial cells. While canonical Wnt reporter activity was also absent from the postnatal lens, upon lens injury intended to model cataract surgery, it upregulated within 12 h in remnant lens epithelial cells, and co-localized with alpha smooth muscle actin in fibrotic lens epithelial cells from 48 h post-surgery onward. This pattern correlated with downregulation of the inhibitor of canonical Wnt signaling, Dkk3. These data demonstrate that canonical Wnt signaling is dynamic within the developing eye and upregulates in lens epithelial cells in response to lens injury. As canonical Wnt signaling can collaborate with TGFβ to drive fibrosis in other systems, these data offer the first evidence in a lens-injury model that canonical Wnt may synergize with TGFβ signaling to drive fibrotic posterior capsular opacification (PCO).
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Affiliation(s)
- Yichen Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States
| | - Priyha Mahesh
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States
| | - Samuel G Novo
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States
| | - Mahbubul H Shihan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States
| | | | - Melinda K Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, United States.
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35
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Meng Q, Mongan M, Wang J, Xia Y. Repression of MAP3K1 expression and JNK activity by canonical Wnt signaling. Dev Biol 2018; 440:129-136. [PMID: 29787744 DOI: 10.1016/j.ydbio.2018.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/10/2018] [Accepted: 05/10/2018] [Indexed: 10/16/2022]
Abstract
Morphogenesis is a complex and highly coordinated process orchestrated by temporal spatial activity of developmental pathways. How the different pathways interact to guide the developmental program remains an intriguing and open question. MAP3K1-JNK and Wnt are signaling pathways crucial for embryonic eyelid closure, an epithelial morphogenetic event conserved in mammals. Here we used a mouse model of eyelid development and genetic and biochemistry tools to investigate the relationships between the two pathways. We found that Wnt activation repressed MAP3K1 expression. Using Axin-LacZ reporter mice, spatial Wnt activity was detected in the leading edge of the developing eyelid. Conditional knockout of Wntless (Wls) in ocular surface ectoderm blocked eyelid formation, and significantly increased MAP3K1 expression in eyelid cells at the nasal canthus region. Conversely, knockout of Dkk2, encoding a canonical Wnt antagonist, resulted in an increase of Wnt activity in cells at the upper eyelid margin near the nasal canthus. Up-regulation of Wnt signaling in the Dkk2-knockout embryos corresponded to down-regulation of MAP3K1 expression. In vitro data showed that Wnt3a treatment decreased MAP3K1 promoter activity, whereas activation of Wnt by lithium chloride inhibited MAP3K1 expression, and attenuated MAP3K1-mediated JNK activity. Our data identify a unique signal crosstalk between Wnt signaling and the MAP3K1-JNK pathway in epithelial morphogenesis.
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Affiliation(s)
- Qinghang Meng
- Department of Environmental Health, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Maureen Mongan
- Department of Environmental Health, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Jingjing Wang
- Department of Environmental Health, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Ying Xia
- Department of Environmental Health, University of Cincinnati, College of Medicine, Cincinnati, OH, USA.
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36
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Dynamic Tissue Rearrangements during Vertebrate Eye Morphogenesis: Insights from Fish Models. J Dev Biol 2018; 6:jdb6010004. [PMID: 29615553 PMCID: PMC5875564 DOI: 10.3390/jdb6010004] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 02/22/2018] [Accepted: 02/27/2018] [Indexed: 12/16/2022] Open
Abstract
Over the last thirty years, fish models, such as the zebrafish and medaka, have become essential to pursue developmental studies and model human disease. Community efforts have led to the generation of wide collections of mutants, a complete sequence of their genomes, and the development of sophisticated genetic tools, enabling the manipulation of gene activity and labelling and tracking of specific groups of cells during embryonic development. When combined with the accessibility and optical clarity of fish embryos, these approaches have made of them an unbeatable model to monitor developmental processes in vivo and in real time. Over the last few years, live-imaging studies in fish have provided fascinating insights into tissue morphogenesis and organogenesis. This review will illustrate the advantages of fish models to pursue morphogenetic studies by highlighting the findings that, in the last decade, have transformed our understanding of eye morphogenesis.
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37
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Lovatt M, Yam GHF, Peh GS, Colman A, Dunn NR, Mehta JS. Directed differentiation of periocular mesenchyme from human embryonic stem cells. Differentiation 2018; 99:62-69. [DOI: 10.1016/j.diff.2017.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Revised: 10/31/2017] [Accepted: 11/08/2017] [Indexed: 12/13/2022]
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Martinez-Morales JR, Cavodeassi F, Bovolenta P. Coordinated Morphogenetic Mechanisms Shape the Vertebrate Eye. Front Neurosci 2017; 11:721. [PMID: 29326547 PMCID: PMC5742352 DOI: 10.3389/fnins.2017.00721] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 12/11/2017] [Indexed: 11/22/2022] Open
Abstract
The molecular bases of vertebrate eye formation have been extensively investigated during the past 20 years. This has resulted in the definition of the backbone of the gene regulatory networks controlling the different steps of eye development and has further highlighted a substantial conservation of these networks among vertebrates. Yet, the precise morphogenetic events allowing the formation of the optic cup from a small group of cells within the anterior neural plate are still poorly understood. It is also unclear if the morphogenetic events leading to eyes of very similar shape are indeed comparable among all vertebrates or if there are any species-specific peculiarities. Improved imaging techniques have enabled to follow how the eye forms in living embryos of a few vertebrate models, whereas the development of organoid cultures has provided fascinating tools to recapitulate tissue morphogenesis of other less accessible species. Here, we will discuss what these advances have taught us about eye morphogenesis, underscoring possible similarities and differences among vertebrates. We will also discuss the contribution of cell shape changes to this process and how morphogenetic and patterning mechanisms integrate to assemble the final architecture of the eye.
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Affiliation(s)
| | - Florencia Cavodeassi
- Centro de Biología Molecular Severo Ochoa, (CSIC/UAM), Madrid, Spain.,CIBERER, ISCIII, Madrid, Spain
| | - Paola Bovolenta
- Centro de Biología Molecular Severo Ochoa, (CSIC/UAM), Madrid, Spain.,CIBERER, ISCIII, Madrid, Spain
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39
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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: 120] [Impact Index Per Article: 17.1] [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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40
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Smith R, Huang YT, Tian T, Vojtasova D, Mesalles-Naranjo O, Pollard SM, Pratt T, Price DJ, Fotaki V. The Transcription Factor Foxg1 Promotes Optic Fissure Closure in the Mouse by Suppressing Wnt8b in the Nasal Optic Stalk. J Neurosci 2017; 37:7975-7993. [PMID: 28729440 PMCID: PMC5559767 DOI: 10.1523/jneurosci.0286-17.2017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/25/2017] [Accepted: 07/02/2017] [Indexed: 11/21/2022] Open
Abstract
During vertebrate eye morphogenesis, a transient fissure forms at its inferior part, known as the optic fissure. This will gradually close, giving rise to a healthy, spherical optic cup. Failure of the optic fissure to close gives rise to an ocular disorder known as coloboma. During this developmental process, Foxg1 is expressed in the optic neuroepithelium, with highest levels of expression in the nasal optic stalk. Foxg1-/- mutant mice have microphthalmic eyes with a large ventral coloboma. We found Wnt8b expression upregulated in the Foxg1-/- optic stalk and hypothesized that, similar to what is observed in telencephalic development, Foxg1 directs development of the optic neuroepithelium through transcriptional suppression of Wnt8b To test this, we generated Foxg1-/-;Wnt8b-/- double mutants of either sex and found that the morphology of the optic cup and stalk and the closure of the optic fissure were substantially rescued in these embryos. This rescue correlates with restored Pax2 expression in the anterior tip of the optic fissure. In addition, although we do not find evidence implicating altered proliferation in the rescue, we observe a significant increase in apoptotic cell density in Foxg1-/-;Wnt8b-/- double mutants compared with the Foxg1-/- single mutant. Upregulation of Wnt/β-catenin target molecules in the optic cup and stalk may underlie the molecular and morphological defects in the Foxg1-/- mutant. Our results show that proper optic fissure closure relies on Wnt8b suppression by Foxg1 in the nasal optic stalk to maintain balanced apoptosis and Pax2 expression in the nasal and temporal edges of the fissure.SIGNIFICANCE STATEMENT Coloboma is an ocular disorder that may result in a loss of visual acuity and accounts for ∼10% of childhood blindness. It results from errors in the sealing of the optic fissure (OF), a transient structure at the bottom of the eye. Here, we investigate the colobomatous phenotype of the Foxg1-/- mutant mouse. We identify upregulated expression of Wnt8b in the optic stalk of Foxg1-/- mutants before OF closure initiates. Foxg1-/-;Wnt8b-/- double mutants show a substantial rescue of the Foxg1-/- coloboma phenotype, which correlates with a rescue in molecular and cellular defects of Foxg1-/- mutants. Our results unravel a new role of Foxg1 in promoting OF closure providing additional knowledge about the molecules and cellular mechanisms underlying coloboma formation.
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Affiliation(s)
- Rowena Smith
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom
| | - Yu-Ting Huang
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom
| | - Tian Tian
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom
| | - Dominika Vojtasova
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom
| | - Oscar Mesalles-Naranjo
- Information Service Division, NHS National Services Scotland, Edinburgh, EH12 9EB, United Kingdom
| | - Steven M Pollard
- Medical Research Council Centre for Regenerative Medicine, Edinburgh, EH16 4UU, United Kingdom, and
- Edinburgh Cancer Research UK Cancer Centre, Edinburgh, EH16 4UU, United Kingdom
| | - Thomas Pratt
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom
| | - David J Price
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom
| | - Vassiliki Fotaki
- Edinburgh Medical School, Biomedical Sciences, Centre for Integrative Physiology, Edinburgh, EH8 9XD, United Kingdom,
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41
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Vallée A, Lecarpentier Y, Guillevin R, Vallée JN. Aerobic Glycolysis Hypothesis Through WNT/Beta-Catenin Pathway in Exudative Age-Related Macular Degeneration. J Mol Neurosci 2017; 62:368-379. [PMID: 28689265 DOI: 10.1007/s12031-017-0947-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 06/28/2017] [Indexed: 12/18/2022]
Abstract
Exudative age-related macular degeneration (AMD) is characterized by molecular mechanisms responsible for the initiation of choroidal neovascularization (CNV). Inflammatory processes are associated with upregulation of the canonical WNT/beta-catenin pathway in exudative AMD. We focus this review on the link between WNT/beta-catenin pathway activation and neovascular progression in exudative AMD through activation of aerobic glycolysis for production of angiogenic factors. Increased WNT/beta-catenin pathway involves hexokinase 2 (HK2) and pyruvate kinase M2 (PKM2). WNT/beta-catenin pathway stimulates PI3K/Akt pathway and then HIF-1alpha which activates glycolytic enzymes: glucose transporter (Glut), pyruvate dehydrogenase kinase 1 (PDK1), lactate dehydrogenase A (LDH-A), and monocarboxylate lactate transporter (MCT-1). This phenomenon is called aerobic glycolysis or the Warburg effect. Consequently, phosphorylation of PDK-1 inhibits the pyruvate dehydrogenase complex (PDH). Thus, a large part of pyruvate cannot be converted into acetyl-CoA in mitochondria and only a part of acetyl-CoA can enter the tricarboxylic acid cycle. Cytosolic pyruvate is converted into lactate through the action of LDH-A. In exudative AMD, high level of cytosolic lactate is correlated with increase of VEGF expression, the angiogenic factor of CNV. Photoreceptors in retina cells can metabolize glucose through aerobic glycolysis to protect them against oxidative damage, as cancer cells do.
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Affiliation(s)
- Alexandre Vallée
- Experimental and Clinical Neurosciences Laboratory, INSERM U1084, University of Poitiers, Poitiers, France.
- Laboratoire de Mathématiques et Applications (LMA), UMR CNRS 7348, Université de Poitiers, 11 Boulevard Marie et Pierre Curie, Poitiers, France.
| | | | - Rémy Guillevin
- DACTIM, Laboratoire de Mathématiques et Applications, Université de Poitiers et CHU de Poitiers, UMR CNRS 7348, SP2MI Futuroscope, Chasseneuil-du-Poitou, France
| | - Jean-Noël Vallée
- Laboratoire de Mathématiques et Applications (LMA), UMR CNRS 7348, Université de Poitiers, 11 Boulevard Marie et Pierre Curie, Poitiers, France
- CHU Amiens Picardie, Université Picardie Jules Verne (UPJV), Amiens, France
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Alldredge A, Fuhrmann S. Loss of Axin2 Causes Ocular Defects During Mouse Eye Development. Invest Ophthalmol Vis Sci 2017; 57:5253-5262. [PMID: 27701636 PMCID: PMC5054732 DOI: 10.1167/iovs.15-18599] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose The scaffold protein Axin2 is an antagonist and universal target of the Wnt/β-catenin pathway. Disruption of Axin2 may lead to developmental eye defects; however, this has not been examined. The purpose of this study was to investigate the role of Axin2 during ocular and extraocular development in mouse. Methods Animals heterozygous and homozygous for a Axin2lacZ knock-in allele were analyzed at different developmental stages for reporter expression, morphology as well as for the presence of ocular and extraocular markers using histologic and immunohistochemical techniques. Results During early eye development, the Axin2lacZ reporter was expressed in the periocular mesenchyme, RPE, and optic stalk. In the developing retina, Axin2lacZ reporter expression was initiated in ganglion cells at late embryonic stages and robustly expressed in subpopulations of amacrine and horizontal cells postnatally. Activation of the Axin2lacZ reporter overlapped with labeling of POU4F1, PAX6, and Calbindin. Germline deletion of Axin2 led to variable ocular phenotypes ranging from normal to severely defective eyes exhibiting microphthalmia, coloboma, lens defects, and expanded ciliary margin. These defects were correlated with abnormal tissue patterning in individual affected tissues, such as the optic fissure margins in the ventral optic cup and in the expanded ciliary margin. Conclusions Our results reveal a critical role for Axin2 during ocular development, likely by restricting the activity of the Wnt/β-catenin pathway.
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Affiliation(s)
- Ashley Alldredge
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, Tennessee, United States
| | - Sabine Fuhrmann
- Department of Ophthalmology and Visual Sciences, Vanderbilt Eye Institute, Vanderbilt University Medical Center, Nashville, Tennessee, United States
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43
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Fujimura N. WNT/β-Catenin Signaling in Vertebrate Eye Development. Front Cell Dev Biol 2016; 4:138. [PMID: 27965955 PMCID: PMC5127792 DOI: 10.3389/fcell.2016.00138] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 11/09/2016] [Indexed: 01/04/2023] Open
Abstract
The vertebrate eye is a highly specialized sensory organ, which is derived from the anterior neural plate, head surface ectoderm, and neural crest-derived mesenchyme. The single central eye field, generated from the anterior neural plate, divides to give rise to the optic vesicle, which evaginates toward the head surface ectoderm. Subsequently, the surface ectoderm, in conjunction with the optic vesicle invaginates to form the lens vesicle and double-layered optic cup, respectively. This complex process is controlled by transcription factors and several intracellular and extracellular signaling pathways including WNT/β-catenin signaling. This signaling pathway plays an essential role in multiple developmental processes and has a profound effect on cell proliferation and cell fate determination. During eye development, the activity of WNT/β-catenin signaling is tightly controlled. Faulty regulation of WNT/β-catenin signaling results in multiple ocular malformations due to defects in the process of cell fate determination and differentiation. This mini-review summarizes recent findings on the role of WNT/β-catenin signaling in eye development. Whilst this mini-review focuses on loss-of-function and gain-of-function mutants of WNT/β-catenin signaling components, it also highlights some important aspects of β-catenin-independent WNT signaling in the eye development at later stages.
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Affiliation(s)
- Naoko Fujimura
- Laboratory of Eye Biology, BIOCEV Division, Institute of Molecular Genetics Prague, Czechia
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44
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Capowski EE, Wright LS, Liang K, Phillips MJ, Wallace K, Petelinsek A, Hagstrom A, Pinilla I, Borys K, Lien J, Min JH, Keles S, Thomson JA, Gamm DM. Regulation of WNT Signaling by VSX2 During Optic Vesicle Patterning in Human Induced Pluripotent Stem Cells. Stem Cells 2016; 34:2625-2634. [PMID: 27301076 DOI: 10.1002/stem.2414] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/28/2016] [Indexed: 12/22/2022]
Abstract
Few gene targets of Visual System Homeobox 2 (VSX2) have been identified despite its broad and critical role in the maintenance of neural retina (NR) fate during early retinogenesis. We performed VSX2 ChIP-seq and ChIP-PCR assays on early stage optic vesicle-like structures (OVs) derived from human iPS cells (hiPSCs), which highlighted WNT pathway genes as direct regulatory targets of VSX2. Examination of early NR patterning in hiPSC-OVs from a patient with a functional null mutation in VSX2 revealed mis-expression and upregulation of WNT pathway components and retinal pigmented epithelium (RPE) markers in comparison to control hiPSC-OVs. Furthermore, pharmacological inhibition of WNT signaling rescued the early mutant phenotype, whereas augmentation of WNT signaling in control hiPSC-OVs phenocopied the mutant. These findings reveal an important role for VSX2 as a regulator of WNT signaling and suggest that VSX2 may act to maintain NR identity at the expense of RPE in part by direct repression of WNT pathway constituents. Stem Cells 2016;34:2625-2634.
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Affiliation(s)
| | - Lynda S Wright
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Kun Liang
- Statistics and Actuarial Science, University of Waterloo, Waterloo, ON, Canada
| | - M Joseph Phillips
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Kyle Wallace
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Anna Petelinsek
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Anna Hagstrom
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Isabel Pinilla
- Aragon Institute for Health Research (IIS Aragón), Lozano Blesa University Hospital, Zaragoza, 50009, Spain.,Department of Ophthalmology, Lozano Blesa University Hospital, Zaragoza, 50009, Spain
| | - Katarzyna Borys
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Jessica Lien
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Jee Hong Min
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Sunduz Keles
- Department of Statistics, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | | | - David M Gamm
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53705, USA.,McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, 53705, USA.,Department of Ophthamology and Visual Sciences, University of Wisconsin-Madison, Madison, WI, 53705, USA
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45
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Abstract
Morphogenesis is the developmental process by which tissues and organs acquire the shape that is critical to their function. Here, we review recent advances in our understanding of the mechanisms that drive morphogenesis in the developing eye. These investigations have shown that regulation of the actin cytoskeleton is central to shaping the presumptive lens and retinal epithelia that are the major components of the eye. Regulation of the actin cytoskeleton is mediated by Rho family GTPases, by signaling pathways and indirectly, by transcription factors that govern the expression of critical genes. Changes in the actin cytoskeleton can shape cells through the generation of filopodia (that, in the eye, connect adjacent epithelia) or through apical constriction, a process that produces a wedge-shaped cell. We have also learned that one tissue can influence the shape of an adjacent one, probably by direct force transmission, in a process we term inductive morphogenesis. Though these mechanisms of morphogenesis have been identified using the eye as a model system, they are likely to apply broadly where epithelia influence the shape of organs during development.
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