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Bosze B, Suarez-Navarro J, Cajias I, Brzezinski IV JA, Brown NL. Notch pathway mutants do not equivalently perturb mouse embryonic retinal development. PLoS Genet 2023; 19:e1010928. [PMID: 37751417 PMCID: PMC10522021 DOI: 10.1371/journal.pgen.1010928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 08/16/2023] [Indexed: 09/28/2023] Open
Abstract
In the vertebrate eye, Notch ligands, receptors, and ternary complex components determine the destiny of retinal progenitor cells in part by regulating Hes effector gene activity. There are multiple paralogues for nearly every node in this pathway, which results in numerous instances of redundancy and compensation during development. To dissect such complexity at the earliest stages of eye development, we used seven germline or conditional mutant mice and two spatiotemporally distinct Cre drivers. We perturbed the Notch ternary complex and multiple Hes genes to understand if Notch regulates optic stalk/nerve head development; and to test intracellular pathway components for their Notch-dependent versus -independent roles during retinal ganglion cell and cone photoreceptor competence and fate acquisition. We confirmed that disrupting Notch signaling universally blocks progenitor cell growth, but delineated specific pathway components that can act independently, such as sustained Hes1 expression in the optic stalk/nerve head. In retinal progenitor cells, we found that among the genes tested, they do not uniformly suppress retinal ganglion cell or cone differentiation; which is not due differences in developmental timing. We discovered that shifts in the earliest cell fates correlate with expression changes for the early photoreceptor factor Otx2, but not with Atoh7, a factor required for retinal ganglion cell formation. During photoreceptor genesis we also better defined multiple and simultaneous activities for Rbpj and Hes1 and identify redundant activities that occur downstream of Notch. Given its unique roles at the retina-optic stalk boundary and cone photoreceptor genesis, our data suggest Hes1 as a hub where Notch-dependent and -independent inputs converge.
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Affiliation(s)
- Bernadett Bosze
- Department of Cell Biology & Human Anatomy, University of California, Davis, California, United States of America
| | - Julissa Suarez-Navarro
- Department of Cell Biology & Human Anatomy, University of California, Davis, California, United States of America
| | - Illiana Cajias
- Department of Cell Biology & Human Anatomy, University of California, Davis, California, United States of America
| | - Joseph A. Brzezinski IV
- Department of Ophthalmology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Nadean L. Brown
- Department of Cell Biology & Human Anatomy, University of California, Davis, California, United States of America
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2
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Katsura M, Urade Y, Nansai H, Kobayashi M, Taguchi A, Ishikawa Y, Ito T, Fukunaga H, Tozawa H, Chikaoka Y, Nakaki R, Echigo A, Kohro T, Sone H, Wada Y. Low-dose radiation induces unstable gene expression in developing human iPSC-derived retinal ganglion organoids. Sci Rep 2023; 13:12888. [PMID: 37558727 PMCID: PMC10412642 DOI: 10.1038/s41598-023-40051-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 08/03/2023] [Indexed: 08/11/2023] Open
Abstract
The effects of low-dose radiation on undifferentiated cells carry important implications. However, the effects on developing retinal cells remain unclear. Here, we analyzed the gene expression characteristics of neuronal organoids containing immature human retinal cells under low-dose radiation and predicted their changes. Developing retinal cells generated from human induced pluripotent stem cells (iPSCs) were irradiated with either 30 or 180 mGy on days 4-5 of development for 24 h. Genome-wide gene expression was observed until day 35. A knowledge-based pathway analysis algorithm revealed fluctuations in Rho signaling and many other pathways. After a month, the levels of an essential transcription factor of eye development, the proportion of paired box 6 (PAX6)-positive cells, and the proportion of retinal ganglion cell (RGC)-specific transcription factor POU class 4 homeobox 2 (POU4F2)-positive cells increased with 30 mGy of irradiation. In contrast, they decreased after 180 mGy of irradiation. Activation of the "development of neurons" pathway after 180 mGy indicated the dedifferentiation and development of other neural cells. Fluctuating effects after low-dose radiation exposure suggest that developing retinal cells employ hormesis and dedifferentiation mechanisms in response to stress.
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Affiliation(s)
- Mari Katsura
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
- Reiwa Eye Clinic, Hatsukaichi, Hiroshima, Japan
| | - Yoshihiro Urade
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Hiroko Nansai
- Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Mika Kobayashi
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Akashi Taguchi
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Yukiko Ishikawa
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Tomohiro Ito
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan
| | - Hisako Fukunaga
- Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Hideto Tozawa
- Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yoko Chikaoka
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | | | | | - Takahide Kohro
- Department of Clinical Informatics, Jichi Medical University, Shimotsuke, Tochigi, Japan
| | - Hideko Sone
- Center for Health and Environmental Risk Research, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan.
- Environmental Health and Prevention Research Unit, Yokohama University of Pharmacy, Yokohama, Japan.
| | - Youichiro Wada
- Isotope Science Center, The University of Tokyo, Tokyo, Japan.
- Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan.
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3
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Saleh AJ, Ahmed Y, Peters LO, Nothwang HG. Comparative expression analysis of the Atoh7 gene regulatory network in the mouse and chicken auditory hindbrain. Cell Tissue Res 2023:10.1007/s00441-023-03763-9. [PMID: 36961563 DOI: 10.1007/s00441-023-03763-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 03/09/2023] [Indexed: 03/25/2023]
Abstract
The mammalian and avian auditory brainstem likely arose by independent evolution. To compare the underlying molecular mechanisms, we focused on Atoh7, as its expression pattern in the mammalian hindbrain is restricted to bushy cells in the ventral cochlear nucleus. We thereby took advantage of an Atoh7 centered gene regulatory network (GRN) in the retina including upstream regulators, Hes1 and Pax6, and downstream targets, Ebf3 and Eya2. In situ hybridization demonstrated for the latter four genes broad expression in all three murine cochlear nuclei at postnatal days (P) 4 and P30, contrasting the restricted expression of Atoh7. In chicken, all five transcription factors were expressed in all auditory hindbrain nuclei at embryonic day (E) 13 and P14. Notably, all five genes showed graded expression in the embryonic nucleus magnocellularis (NM). Atoh7 was highly expressed in caudally located neurons, whereas the other four transcription factors were highly expressed in rostrally located neurons. Thus, Atoh7 shows a strikingly different expression between the mammalian and avian auditory hindbrain. This together with the consistent absence of graded expression of GRN components in developing mammalian nuclei provide the first molecular support to the current view of convergent evolution as a major mechanism in the amniote auditory hindbrain. The graded expression of five transcription factors specifically in the developing NM confirms this nucleus as a central organizer of tonotopic features in birds. Finally, the expression of all five retinal GRN components in the auditory system suggests co-options of genes for development of sensory systems of distinct modalities.
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Affiliation(s)
- Ali Jason Saleh
- Division of Neurogenetics and Cluster of Excellence "Hearing4all", School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, 26111, Oldenburg, Germany
| | - Yannis Ahmed
- Institute of Neurophysiopathology (INP), Aix-Marseille University, CNRS, Marseille, France
| | - Lars-Oliver Peters
- Division of Neurogenetics and Cluster of Excellence "Hearing4all", School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, 26111, Oldenburg, Germany
| | - Hans Gerd Nothwang
- Division of Neurogenetics and Cluster of Excellence "Hearing4all", School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, 26111, Oldenburg, Germany.
- Research Center for Neurosensory Science, Carl von Ossietzky University Oldenburg, 26111, Oldenburg, Germany.
- Department of Neuroscience, Cluster of Excellence "Hearing4all", Carl von Ossietzky University Oldenburg, 26111, Oldenburg, Germany.
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4
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Diacou R, Nandigrami P, Fiser A, Liu W, Ashery-Padan R, Cvekl A. Cell fate decisions, transcription factors and signaling during early retinal development. Prog Retin Eye Res 2022; 91:101093. [PMID: 35817658 PMCID: PMC9669153 DOI: 10.1016/j.preteyeres.2022.101093] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 12/30/2022]
Abstract
The development of the vertebrate eyes is a complex process starting from anterior-posterior and dorso-ventral patterning of the anterior neural tube, resulting in the formation of the eye field. Symmetrical separation of the eye field at the anterior neural plate is followed by two symmetrical evaginations to generate a pair of optic vesicles. Next, reciprocal invagination of the optic vesicles with surface ectoderm-derived lens placodes generates double-layered optic cups. The inner and outer layers of the optic cups develop into the neural retina and retinal pigment epithelium (RPE), respectively. In vitro produced retinal tissues, called retinal organoids, are formed from human pluripotent stem cells, mimicking major steps of retinal differentiation in vivo. This review article summarizes recent progress in our understanding of early eye development, focusing on the formation the eye field, optic vesicles, and early optic cups. Recent single-cell transcriptomic studies are integrated with classical in vivo genetic and functional studies to uncover a range of cellular mechanisms underlying early eye development. The functions of signal transduction pathways and lineage-specific DNA-binding transcription factors are dissected to explain cell-specific regulatory mechanisms underlying cell fate determination during early eye development. The functions of homeodomain (HD) transcription factors Otx2, Pax6, Lhx2, Six3 and Six6, which are required for early eye development, are discussed in detail. Comprehensive understanding of the mechanisms of early eye development provides insight into the molecular and cellular basis of developmental ocular anomalies, such as optic cup coloboma. Lastly, modeling human development and inherited retinal diseases using stem cell-derived retinal organoids generates opportunities to discover novel therapies for retinal diseases.
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Affiliation(s)
- Raven Diacou
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Prithviraj Nandigrami
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Andras Fiser
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Wei Liu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Ruth Ashery-Padan
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - Ales Cvekl
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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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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6
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Loss of Hes1 in embryonic stem cells caused developmental disorders in retinal pigment epithelium morphogenesis and specification. Biochem Biophys Res Commun 2022; 632:76-84. [DOI: 10.1016/j.bbrc.2022.09.080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 08/23/2022] [Accepted: 09/21/2022] [Indexed: 11/20/2022]
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Aniridia-related keratopathy relevant cell signaling pathways in human fetal corneas. Histochem Cell Biol 2022; 158:169-180. [PMID: 35551459 PMCID: PMC9338123 DOI: 10.1007/s00418-022-02099-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2022] [Indexed: 11/26/2022]
Abstract
We aimed to study aniridia-related keratopathy (ARK) relevant cell signaling pathways [Notch1, Wnt/β-catenin, Sonic hedgehog (SHH) and mTOR] in normal human fetal corneas compared with normal human adult corneas and ARK corneas. We found that fetal corneas at 20 weeks of gestation (wg) and normal adult corneas showed similar staining patterns for Notch1; however 10–11 wg fetal corneas showed increased presence of Notch1. Numb and Dlk1 had an enhanced presence in the fetal corneas compared with the adult corneas. Fetal corneas showed stronger immunolabeling with antibodies against β-catenin, Wnt5a, Wnt7a, Gli1, Hes1, p-rpS6, and mTOR when compared with the adult corneas. Gene expression of Notch1, Wnt5A, Wnt7A, β-catenin, Hes1, mTOR, and rps6 was higher in the 9–12 wg fetal corneas compared with adult corneas. The cell signaling pathway differences found between human fetal and adult corneas were similar to those previously found in ARK corneas with the exception of Notch1. Analogous profiles of cell signaling pathway activation between human fetal corneas and ARK corneas suggests that there is a less differentiated host milieu in ARK.
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8
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Disatham J, Brennan L, Jiao X, Ma Z, Hejtmancik JF, Kantorow M. Changes in DNA methylation hallmark alterations in chromatin accessibility and gene expression for eye lens differentiation. Epigenetics Chromatin 2022; 15:8. [PMID: 35246225 PMCID: PMC8897925 DOI: 10.1186/s13072-022-00440-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/16/2022] [Indexed: 12/13/2022] Open
Abstract
Background Methylation at cytosines (mCG) is a well-known regulator of gene expression, but its requirements for cellular differentiation have yet to be fully elucidated. A well-studied cellular differentiation model system is the eye lens, consisting of a single anterior layer of epithelial cells that migrate laterally and differentiate into a core of fiber cells. Here, we explore the genome-wide relationships between mCG methylation, chromatin accessibility and gene expression during differentiation of eye lens epithelial cells into fiber cells. Results Whole genome bisulfite sequencing identified 7621 genomic loci exhibiting significant differences in mCG levels between lens epithelial and fiber cells. Changes in mCG levels were inversely correlated with the differentiation state-specific expression of 1285 genes preferentially expressed in either lens fiber or lens epithelial cells (Pearson correlation r = − 0.37, p < 1 × 10–42). mCG levels were inversely correlated with chromatin accessibility determined by assay for transposase-accessible sequencing (ATAC-seq) (Pearson correlation r = − 0.86, p < 1 × 10–300). Many of the genes exhibiting altered regions of DNA methylation, chromatin accessibility and gene expression levels in fiber cells relative to epithelial cells are associated with lens fiber cell structure, homeostasis and transparency. These include lens crystallins (CRYBA4, CRYBB1, CRYGN, CRYBB2), lens beaded filament proteins (BFSP1, BFSP2), transcription factors (HSF4, SOX2, HIF1A), and Notch signaling pathway members (NOTCH1, NOTCH2, HEY1, HES5). Analysis of regions exhibiting cell-type specific alterations in DNA methylation revealed an overrepresentation of consensus sequences of multiple transcription factors known to play key roles in lens cell differentiation including HIF1A, SOX2, and the MAF family of transcription factors. Conclusions Collectively, these results link DNA methylation with control of chromatin accessibility and gene expression changes required for eye lens differentiation. The results also point to a role for DNA methylation in the regulation of transcription factors previously identified to be important for lens cell differentiation. Supplementary Information The online version contains supplementary material available at 10.1186/s13072-022-00440-z.
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Affiliation(s)
- Joshua Disatham
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Lisa Brennan
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA
| | - Xiaodong Jiao
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Zhiwei Ma
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - J Fielding Hejtmancik
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Marc Kantorow
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
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9
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Gabriel E, Albanna W, Pasquini G, Ramani A, Josipovic N, Mariappan A, Schinzel F, Karch CM, Bao G, Gottardo M, Suren AA, Hescheler J, Nagel-Wolfrum K, Persico V, Rizzoli SO, Altmüller J, Riparbelli MG, Callaini G, Goureau O, Papantonis A, Busskamp V, Schneider T, Gopalakrishnan J. Human brain organoids assemble functionally integrated bilateral optic vesicles. Cell Stem Cell 2021; 28:1740-1757.e8. [PMID: 34407456 DOI: 10.1016/j.stem.2021.07.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 04/23/2021] [Accepted: 07/20/2021] [Indexed: 02/07/2023]
Abstract
During embryogenesis, optic vesicles develop from the diencephalon via a multistep process of organogenesis. Using induced pluripotent stem cell (iPSC)-derived human brain organoids, we attempted to simplify the complexities and demonstrate formation of forebrain-associated bilateral optic vesicles, cellular diversity, and functionality. Around day 30, brain organoids attempt to assemble optic vesicles, which develop progressively as visible structures within 60 days. These optic vesicle-containing brain organoids (OVB-organoids) constitute a developing optic vesicle's cellular components, including primitive corneal epithelial and lens-like cells, retinal pigment epithelia, retinal progenitor cells, axon-like projections, and electrically active neuronal networks. OVB-organoids also display synapsin-1, CTIP-positive myelinated cortical neurons, and microglia. Interestingly, various light intensities could trigger photosensitive activity of OVB-organoids, and light sensitivities could be reset after transient photobleaching. Thus, brain organoids have the intrinsic ability to self-organize forebrain-associated primitive sensory structures in a topographically restricted manner and can allow interorgan interaction studies within a single organoid.
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Affiliation(s)
- Elke Gabriel
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Walid Albanna
- Institute for Neurophysiology, University of Cologne, 50931 Cologne, Germany; Department of Neurosurgery, RWTH Aachen University, 52074 Aachen, Germany
| | - Giovanni Pasquini
- Department of Ophthalmology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Anand Ramani
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Natasa Josipovic
- Institute of Pathology, University Medicine Göttingen, Georg-August University Göttingen, 37075 Göttingen, Germany; Center for molecular medicine, Cologne, Universität zu Köln, 50931 Köln, Germany
| | - Aruljothi Mariappan
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Friedrich Schinzel
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Celeste M Karch
- Department of Psychiatry, Washington University in St. Louis, St. Louis, MO 63116, USA
| | - Guobin Bao
- Institute of Neurophysiology and Cellular Biophysics, University Medicine Göttingen, Georg-August-Universität Göttingen, 37073 Göttingen, Germany
| | - Marco Gottardo
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Ata Alp Suren
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany
| | - Jürgen Hescheler
- Institute for Neurophysiology, University of Cologne, 50931 Cologne, Germany
| | - Kerstin Nagel-Wolfrum
- Institute of Molecular Physiology, Johannes Gutenberg University, 55099 Mainz, Germany
| | - Veronica Persico
- Department of Life Sciences and Medical Biotechnology University of Siena, Siena 53100, Italy
| | - Silvio O Rizzoli
- Institute of Neurophysiology and Cellular Biophysics, University Medicine Göttingen, Georg-August-Universität Göttingen, 37073 Göttingen, Germany
| | - Janine Altmüller
- Cologne Center for Genomics (CCG), Universität zu Köln, Köln, Germany; Center for molecular medicine, Cologne, Universität zu Köln, 50931 Köln, Germany
| | | | - Giuliano Callaini
- Department of Life Sciences and Medical Biotechnology University of Siena, Siena 53100, Italy
| | - Olivier Goureau
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, 75012 Paris, France
| | - Argyris Papantonis
- Institute of Pathology, University Medicine Göttingen, Georg-August University Göttingen, 37075 Göttingen, Germany
| | - Volker Busskamp
- Department of Ophthalmology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Toni Schneider
- Institute for Neurophysiology, University of Cologne, 50931 Cologne, Germany
| | - Jay Gopalakrishnan
- Institute of Human Genetics, University Hospital, Heinrich-Heine-Universität, 40225 Düsseldorf, Germany.
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10
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Zhang X, Mandric I, Nguyen KH, Nguyen TTT, Pellegrini M, Grove JCR, Barnes S, Yang XJ. Single Cell Transcriptomic Analyses Reveal the Impact of bHLH Factors on Human Retinal Organoid Development. Front Cell Dev Biol 2021; 9:653305. [PMID: 34055784 PMCID: PMC8155690 DOI: 10.3389/fcell.2021.653305] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/22/2021] [Indexed: 11/13/2022] Open
Abstract
The developing retina expresses multiple bHLH transcription factors. Their precise functions and interactions in uncommitted retinal progenitors remain to be fully elucidated. Here, we investigate the roles of bHLH factors ATOH7 and Neurog2 in human ES cell-derived retinal organoids. Single cell transcriptome analyses identify three states of proliferating retinal progenitors: pre-neurogenic, neurogenic, and cell cycle-exiting progenitors. Each shows different expression profile of bHLH factors. The cell cycle-exiting progenitors feed into a postmitotic heterozygous neuroblast pool that gives rise to early born neuronal lineages. Elevating ATOH7 or Neurog2 expression accelerates the transition from the pre-neurogenic to the neurogenic state, and expands the exiting progenitor and neuroblast populations. In addition, ATOH7 and Neurog2 significantly, yet differentially, enhance retinal ganglion cell and cone photoreceptor production. Moreover, single cell transcriptome analyses reveal that ATOH7 and Neurog2 each assert positive autoregulation, and both suppress key bHLH factors associated with the pre-neurogenic and states and elevate bHLH factors expressed by exiting progenitors and differentiating neuroblasts. This study thus provides novel insight regarding how ATOH7 and Neurog2 impact human retinal progenitor behaviors and neuroblast fate choices.
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Affiliation(s)
- Xiangmei Zhang
- Department of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Igor Mandric
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Kevin H Nguyen
- Department of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Thao T T Nguyen
- Department of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Matteo Pellegrini
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - James C R Grove
- Department of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Steven Barnes
- Department of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States.,Doheny Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States
| | - Xian-Jie Yang
- Department of Ophthalmology, Stein Eye Institute, University of California, Los Angeles, Los Angeles, CA, United States.,Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
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11
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Wu F, Bard JE, Kann J, Yergeau D, Sapkota D, Ge Y, Hu Z, Wang J, Liu T, Mu X. Single cell transcriptomics reveals lineage trajectory of retinal ganglion cells in wild-type and Atoh7-null retinas. Nat Commun 2021; 12:1465. [PMID: 33674582 PMCID: PMC7935890 DOI: 10.1038/s41467-021-21704-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 02/09/2021] [Indexed: 01/31/2023] Open
Abstract
Atoh7 has been believed to be essential for establishing the retinal ganglion cell (RGC) lineage, and Pou4f2 and Isl1 are known to regulate RGC specification and differentiation. Here we report our further study of the roles of these transcription factors. Using bulk RNA-seq, we identify genes regulated by the three transcription factors, which expand our understanding of the scope of downstream events. Using scRNA-seq on wild-type and mutant retinal cells, we reveal a transitional cell state of retinal progenitor cells (RPCs) co-marked by Atoh7 and other genes for different lineages and shared by all early retinal lineages. We further discover the unexpected emergence of the RGC lineage in the absence of Atoh7. We conclude that competence of RPCs for different retinal fates is defined by lineage-specific genes co-expressed in the transitional state and that Atoh7 defines the RGC competence and collaborates with other factors to shepherd transitional RPCs to the RGC lineage.
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Affiliation(s)
- Fuguo Wu
- Department of Ophthalmology/Ross Eye Institute, University at Buffalo, Buffalo, NY, USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Jonathan E Bard
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Julien Kann
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Donald Yergeau
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Darshan Sapkota
- Department of Ophthalmology/Ross Eye Institute, University at Buffalo, Buffalo, NY, USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Yichen Ge
- Department of Ophthalmology/Ross Eye Institute, University at Buffalo, Buffalo, NY, USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Zihua Hu
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA
| | - Jie Wang
- Department of Biostatistics & Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Tao Liu
- Department of Biostatistics & Bioinformatics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA
| | - Xiuqian Mu
- Department of Ophthalmology/Ross Eye Institute, University at Buffalo, Buffalo, NY, USA.
- New York State Center of Excellence in Bioinformatics and Life Sciences, University at Buffalo, Buffalo, NY, USA.
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12
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Multiple roles for Pax2 in the embryonic mouse eye. Dev Biol 2021; 472:18-29. [PMID: 33428890 DOI: 10.1016/j.ydbio.2020.12.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/23/2020] [Accepted: 12/24/2020] [Indexed: 02/07/2023]
Abstract
The vertebrate eye anlage grows out of the brain and folds into bilayered optic cups. The eye is patterned along multiple axes, precisely controlled by genetic programs, to delineate neural retina, pigment epithelium, and optic stalk tissues. Pax genes encode developmental regulators of key morphogenetic events, with Pax2 being essential for interpreting inductive signals, including in the eye. PAX2 mutations cause ocular coloboma, when the ventral optic fissure fails to close. Previous studies established that Pax2 is necessary for fissure closure and to maintain the neural retina -- glial optic stalk boundary. Using a Pax2GFP/+ knock-in allele we discovered that the mutant optic nerve head (ONH) lacks molecular boundaries with the retina and RPE, rendering the ONH larger than normal. This was preceded by ventronasal cup mispatterning, a burst of overproliferation and followed by optic cup apoptosis. Our findings support the hypothesis that ONH cells are tripotential, requiring Pax2 to remain committed to glial fates. This work extends current models of ocular development, contributes to broader understanding of tissue boundary formation and informs the underlying mechanisms of human coloboma.
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13
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Sun WR, Ramirez S, Spiller KE, Zhao Y, Fuhrmann S. Nf2 fine-tunes proliferation and tissue alignment during closure of the optic fissure in the embryonic mouse eye. Hum Mol Genet 2020; 29:3373-3387. [PMID: 33075808 DOI: 10.1093/hmg/ddaa228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/29/2020] [Accepted: 10/12/2020] [Indexed: 11/14/2022] Open
Abstract
Uveal coloboma represents one of the most common congenital ocular malformations accounting for up to 10% of childhood blindness (~1 in 5000 live birth). Coloboma originates from defective fusion of the optic fissure (OF), a transient gap that forms during eye morphogenesis by asymmetric, ventral invagination. Genetic heterogeneity combined with the activity of developmentally regulated genes suggests multiple mechanisms regulating OF closure. The tumor suppressor and FERM domain protein Neurofibromin 2 (NF2) controls diverse processes in cancer, development and regeneration, via Hippo pathway and cytoskeleton regulation. In humans, NF2 mutations can cause ocular abnormalities, including coloboma, however, its actual role in OF closure is unknown. Using conditional inactivation in the embryonic mouse eye, our data indicate that loss of Nf2 function results in a novel underlying cause for coloboma. In particular, mutant eyes show substantially increased retinal pigmented epithelium (RPE) proliferation in the fissure region with concomitant acquisition of RPE cell fate. Cells lining the OF margin can maintain RPE fate ectopically and fail to transition from neuroepithelial to cuboidal shape. In the dorsal RPE of the optic cup, Nf2 inactivation leads to a robust increase in cell number, with local disorganization of the cytoskeleton components F-actin and pMLC2. We propose that RPE hyperproliferation is the primary cause for the observed defects causing insufficient alignment of the OF margins in Nf2 mutants and failure to fuse properly, resulting in persistent coloboma. Our findings indicate that limiting proliferation particularly in the RPE layer is a critical mechanism during OF closure.
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Affiliation(s)
- Wesley R Sun
- Department of Ophthalmology and Visual Sciences, VEI, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Sara Ramirez
- Department of Ophthalmology and Visual Sciences, VEI, Vanderbilt University Medical Center, Nashville, TN 37232, USA.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA
| | - Kelly E Spiller
- Department of Ophthalmology and Visual Sciences, VEI, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Yan Zhao
- Department of Ophthalmology and Visual Sciences, VEI, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Sabine Fuhrmann
- Department of Ophthalmology and Visual Sciences, VEI, Vanderbilt University Medical Center, Nashville, TN 37232, USA.,Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37240, USA
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14
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Simultaneous Requirements for Hes1 in Retinal Neurogenesis and Optic Cup-Stalk Boundary Maintenance. J Neurosci 2020; 40:1501-1513. [PMID: 31949107 DOI: 10.1523/jneurosci.2327-19.2020] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 01/02/2020] [Accepted: 01/07/2020] [Indexed: 12/15/2022] Open
Abstract
The bHLH transcription factor Hes1 is a key downstream effector for the Notch signaling pathway. During embryogenesis neural progenitors express low levels of Hes1 in an oscillating pattern, whereas glial brain boundary regions (e.g., isthmus) have high, sustained Hes1 levels that suppress neuronal fates. Here, we show that in the embryonic mouse retina, the optic nerve head and stalk express high Hes1, with the ONH constituting a boundary between the neural retina and glial cells that ultimately line the optic stalk. Using two Cre drivers with distinct spatiotemporal expression we conditionally inactivated Hes1, to delineate the requirements for this transcriptional repressor during retinal neurogenesis versus patterning of the optic cup and stalk. Throughout retinal neurogenesis, Hes1 maintains proliferation and blocks retinal ganglion cell formation, but surprisingly we found it also promotes cone photoreceptor genesis. In the postnatal eye, Hes1 inactivation with Rax-Cre resulted in increased bipolar neurons and a mispositioning of Müller glia. Our results indicate that Notch pathway regulation of cone genesis is more complex than previously assumed, and reveal a novel role for Hes1 in maintaining the optic cup-stalk boundary.SIGNIFICANCE STATEMENT The bHLH repressor Hes1 regulates the timing of neurogenesis, rate of progenitor cell division, gliogenesis, and maintains tissue compartment boundaries. This study expands current eye development models by showing Notch-independent roles for Hes1 in the developing optic nerve head (ONH). Defects in ONH formation result in optic nerve coloboma; our work now inserts Hes1 into the genetic hierarchy regulating optic fissure closure. Given that Hes1 acts analogously in the ONH as the brain isthmus, it prompts future investigation of the ONH as a signaling factor center, or local organizer. Embryonic development of the ONH region has been poorly studied, which is surprising given it is where the pan-ocular disease glaucoma is widely believed to inflict damage on RGC axons.
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15
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Lin S, Guo J, Chen S. Transcriptome and DNA Methylome Signatures Associated With Retinal Müller Glia Development, Injury Response, and Aging. ACTA ACUST UNITED AC 2019; 60:4436-4450. [DOI: 10.1167/iovs.19-27361] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Siyuan Lin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jingyi Guo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shuyi Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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16
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Cheng M, Chu F, Feng Q, Shen G. Cyclic tensile strain promotes the ECM synthesis of cranial base synchondrosis chondrocytes by upregulating miR-140-5p. Orthod Craniofac Res 2019; 23:44-49. [PMID: 31461554 DOI: 10.1111/ocr.12341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 07/28/2019] [Accepted: 08/26/2019] [Indexed: 01/08/2023]
Abstract
OBJECTIVE This study aimed to explore the role of miR-140-5p in cranial base synchondrosis chondrocytes (CBSCs) under cyclic tensile strain (CTS). SETTING AND SAMPLE POPULATION A total of 25 1-week-old Sprague Dawley rats from Shanghai Laboratory Animal Center, Chinese Academy of Sciences, were used. MATERIAL AND METHODS The second passage of CBSCs was applied with CTS at 10% elongation (1 Hz) for 24 hours. MiR-140-5p levels in CBSCs were detected by qRT-PCR. The role of miR-140-5p in CBSCs was evaluated by transfection of mimics and inhibitor. RNA sequencing and online search of miRNA databases (TargetScan, miRDB and miRanda) were used in prediction of miR-140-5p targets. A luciferase reporter assay was applied to identify the target gene of miR-140-5p. RESULTS Compared with the control, the expression of Col2a1 and Sox9 was significantly higher after CTS (P < .05). Also, CBSCs demonstrated higher expression of miR-140-5p after CTS loading for 24 hours (P < .05). Overexpression of miR-140-5p promoted ECM synthesis under CTS loading environment, while suppression of miR-140-5p inhibited the effect. Bloc1s2 was a putative target gene of miR-140-5p. CONCLUSIONS The expression of ECM in CBSCs could be promoted by CTS and miR-140-5p might play a role in this process through targeting Bloc1s2.
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Affiliation(s)
- Mingjia Cheng
- Department of Orthodontics, College of Stomatology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, China
| | - Fengting Chu
- Department of Orthodontics, College of Stomatology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Qiping Feng
- Department of Orthodontics, College of Stomatology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Gang Shen
- Department of Orthodontics, College of Stomatology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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17
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Wiegering A, Petzsch P, Köhrer K, Rüther U, Gerhardt C. GLI3 repressor but not GLI3 activator is essential for mouse eye patterning and morphogenesis. Dev Biol 2019; 450:141-154. [PMID: 30953627 DOI: 10.1016/j.ydbio.2019.02.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/12/2019] [Accepted: 02/15/2019] [Indexed: 12/11/2022]
Abstract
Since 1967, it is known that the loss of GLI3 causes very severe defects in murine eye development. GLI3 is able to act as a transcriptional activator (GLI3-A) or as a transcriptional repressor (GLI3-R). Soon after the discovery of these GLI3 isoforms, the question arose which of the different isoforms is involved in eye formation - GLI3-A, GLI3-R or even both. For several years, this question remained elusive. By analysing the eye morphogenesis of Gli3XtJ/XtJ mouse embryos that lack GLI3-A and GLI3-R and of Gli3Δ699/Δ699 mouse embryos in which only GLI3-A is missing, we revealed that GLI3-A is dispensable in vertebrate eye formation. Remarkably, our study shows that GLI3-R is sufficient for the creation of morphologically normal eyes although the molecular setup deviates substantially from normality. In depth-investigations elucidated that GLI3-R controls numerous key players in eye development and governs lens and retina development at least partially via regulating WNT/β-CATENIN signalling.
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Affiliation(s)
- Antonia Wiegering
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, 40225 Düsseldorf, Germany.
| | - Patrick Petzsch
- Biological and Medical Research Center (BMFZ), Genomics and Transcriptomics Laboratory (GTL), Heinrich Heine University, 40225 Düsseldorf, Germany.
| | - Karl Köhrer
- Biological and Medical Research Center (BMFZ), Genomics and Transcriptomics Laboratory (GTL), Heinrich Heine University, 40225 Düsseldorf, Germany.
| | - Ulrich Rüther
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, 40225 Düsseldorf, Germany.
| | - Christoph Gerhardt
- Institute for Animal Developmental and Molecular Biology, Heinrich Heine University, 40225 Düsseldorf, Germany.
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18
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Lens differentiation is controlled by the balance between PDGF and FGF signaling. PLoS Biol 2019; 17:e3000133. [PMID: 30716082 PMCID: PMC6375662 DOI: 10.1371/journal.pbio.3000133] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 02/14/2019] [Accepted: 01/17/2019] [Indexed: 12/15/2022] Open
Abstract
How multiple receptor tyrosine kinases coordinate cell fate determination is yet to be elucidated. We show here that the receptor for platelet-derived growth factor (PDGF) signaling recruits the p85 subunit of Phosphoinositide 3-kinase (PI3K) to regulate mammalian lens development. Activation of PI3K signaling not only prevents B-cell lymphoma 2 (BCL2)-Associated X (Bax)- and BCL2 Antagonist/Killer (Bak)-mediated apoptosis but also promotes Notch signaling to prevent premature cell differentiation. Reducing PI3K activity destabilizes the Notch intracellular domain, while the constitutive activation of Notch reverses the PI3K deficiency phenotype. In contrast, fibroblast growth factor receptors (FGFRs) recruit Fibroblast Growth Factor Receptor Substrate 2 (Frs2) and Rous sarcoma oncogene (Src) Homology Phosphatase 2 (Shp2) to activate Mitogen-Activated Protein Kinase (MAPK) signaling, which induces the Notch ligand Jagged 1 (Jag1) and promotes cell differentiation. Inactivation of Shp2 restored the proper timing of differentiation in the p85 mutant lens, demonstrating the antagonistic interaction between FGF-induced MAPK and PDGF-induced PI3K signaling. By selective activation of PI3K and MAPK, PDGF and FGF cooperate with and oppose each other to balance progenitor cell maintenance and differentiation. A central aim in understanding cell signaling is to decode the cellular logic that underlies the functional specificity of growth factors. Although these factors are known to activate a common set of intracellular pathways, they nevertheless play specific roles in development and physiology. Using lens development in mice as a model, we show that fibroblast growth factor (FGF) and platelet-derived growth factor (PDGF) antagonize each other through their intrinsic biases toward distinct downstream targets. While FGF primarily induces the Ras–Mitogen-Activated Protein Kinase (MAPK) axis to promote lens cell differentiation, PDGF preferentially stimulates Phosphoinositide 3-kinase (PI3K) to enhance Notch signaling, which is necessary for maintaining the lens progenitor cell pool. By revealing the intricate interactions between PDGF, FGF, and Notch, we present a paradigm for how signaling crosstalk enables balanced growth and differentiation in multicellular organisms.
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19
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Vicente A, Byström B, Pedrosa Domellöf F. Altered Signaling Pathways in Aniridia-Related Keratopathy. ACTA ACUST UNITED AC 2018; 59:5531-5541. [DOI: 10.1167/iovs.18-25175] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- André Vicente
- Department of Clinical Science, Ophthalmology, Umeå University, Umeå, Sweden
| | - Berit Byström
- Department of Clinical Science, Ophthalmology, Umeå University, Umeå, Sweden
| | - Fátima Pedrosa Domellöf
- Department of Clinical Science, Ophthalmology, Umeå University, Umeå, Sweden
- Department of Integrative Medical Biology, Section for Anatomy, Umeå University, Umeå, Sweden
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20
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Miesfeld JB, Moon MS, Riesenberg AN, Contreras AN, Kovall RA, Brown NL. Rbpj direct regulation of Atoh7 transcription in the embryonic mouse retina. Sci Rep 2018; 8:10195. [PMID: 29977079 PMCID: PMC6033939 DOI: 10.1038/s41598-018-28420-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 06/22/2018] [Indexed: 12/24/2022] Open
Abstract
In vertebrate retinal progenitor cells, the proneural factor Atoh7 exhibits a dynamic tissue and cellular expression pattern. Although the resulting Atoh7 retinal lineage contains all seven major cell types, only retinal ganglion cells require Atoh7 for proper differentiation. Such specificity necessitates complex regulation of Atoh7 transcription during retina development. The Notch signaling pathway is an evolutionarily conserved suppressor of proneural bHLH factor expression. Previous in vivo mouse genetic studies established the cell autonomous suppression of Atoh7 transcription by Notch1, Rbpj and Hes1. Here we identify four CSL binding sites within the Atoh7 proximal regulatory region and demonstrate Rbpj protein interaction at these sequences by in vitro electromobility shift, calorimetry and luciferase assays and, in vivo via colocalization and chromatin immunoprecipitation. We found that Rbpj simultaneously represses Atoh7 transcription using both Notch-dependent and –independent pathways.
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Affiliation(s)
- Joel B Miesfeld
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, One Shields Avenue, Davis, CA, 95616, USA
| | - Myung-Soon Moon
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, One Shields Avenue, Davis, CA, 95616, USA.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA
| | - Amy N Riesenberg
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA
| | - Ashley N Contreras
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati School of Medicine, Cincinnati, OH, 45267, USA.,Department of Biology, University of Cincinnati Blue Ash College, Cincinnati, OH, 45236, USA
| | - Rhett A Kovall
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati School of Medicine, Cincinnati, OH, 45267, USA
| | - Nadean L Brown
- Department of Cell Biology & Human Anatomy, University of California Davis School of Medicine, One Shields Avenue, Davis, CA, 95616, USA. .,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA.
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21
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Zhang XM, Hashimoto T, Tang R, Yang XJ. Elevated expression of human bHLH factor ATOH7 accelerates cell cycle progression of progenitors and enhances production of avian retinal ganglion cells. Sci Rep 2018; 8:6823. [PMID: 29717171 PMCID: PMC5931526 DOI: 10.1038/s41598-018-25188-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Accepted: 04/03/2018] [Indexed: 12/13/2022] Open
Abstract
The production of vertebrate retinal projection neurons, retinal ganglion cells (RGCs), is regulated by cell-intrinsic determinants and cell-to-cell signaling events. The basic-helix-loop-helix (bHLH) protein Atoh7 is a key neurogenic transcription factor required for RGC development. Here, we investigate whether manipulating human ATOH7 expression among uncommitted progenitors can promote RGC fate specification and thus be used as a strategy to enhance RGC genesis. Using the chicken retina as a model, we show that cell autonomous expression of ATOH7 is sufficient to induce precocious RGC formation and expansion of the neurogenic territory. ATOH7 overexpression among neurogenic progenitors significantly enhances RGC production at the expense of reducing the progenitor pool. Furthermore, forced expression of ATOH7 leads to a minor increase of cone photoreceptors. We provide evidence that elevating ATOH7 levels accelerates cell cycle progression from S to M phase and promotes cell cycle exit. We also show that ATOH7-induced ectopic RGCs often exhibit aberrant axonal projection patterns and are correlated with increased cell death during the period of retinotectal connections. These results demonstrate the high potency of human ATOH7 in promoting early retinogenesis and specifying the RGC differentiation program, thus providing insight for manipulating RGC production from stem cell-derived retinal organoids.
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Affiliation(s)
- Xiang-Mei Zhang
- Stein Eye Institute, University of California, Los Angeles, CA, USA
| | - Takao Hashimoto
- Stein Eye Institute, University of California, Los Angeles, CA, USA
| | - Ronald Tang
- Stein Eye Institute, University of California, Los Angeles, CA, USA
| | - Xian-Jie Yang
- Stein Eye Institute, University of California, Los Angeles, CA, USA. .,Molecular Biology Institute, University of California, Los Angeles, CA, USA.
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22
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Johnsen EO, Frøen RC, Olstad OK, Nicolaissen B, Petrovski G, Moe MC, Noer A. Proliferative Cells Isolated from the Adult Human Peripheral Retina only Transiently Upregulate Key Retinal Markers upon Induced Differentiation. Curr Eye Res 2017; 43:340-349. [PMID: 29161152 DOI: 10.1080/02713683.2017.1403630] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Purpose/Aim: The adult human retina has limited regenerative potential, and severe injury will result in permanent damage. Lower vertebrates handle retinal injury by activating neural stem cells (NSCs) in the ciliary marginal zone (CMZ). Müller glia-like cells expressing markers of NSCs are also present in the peripheral retina (PR) of the adult human eye, leading to the hypothesis that a CMZ-like zone might exists also in humans. In order to shed further light on this hypothesis we investigated the in vitro differentiation potential of proliferative cells isolated from the adult human PR towards a retinal phenotype. MATERIALS AND METHODS Proliferative cells were isolated from the peripheral retina of human eyes (n = 6) within 24 to 48 hours post mortem and further expanded for 2 or 3 passages before being differentiated for 1-3 weeks. Gene expression was analyzed by microarray and qRT-PCR analysis, while protein expression was identified by immunocytochemistry. RESULTS A high density of cells co-staining with markers for progenitor cells and Müller glia was found in situ in the PR. Cells isolated from this region and cultured adherently showed fibrillary processes and were positive for the immature marker Nestin and the glial marker GFAP, while a few co-expressed PAX6. After 7 days of differentiation, there was a transient upregulation of early and mature photoreceptor markers, including NRL, CRX, RHO and RCVRN, as well as the Müller cell and retinal pigmented epithelium (RPE) marker CRALBP, and the early RPE marker MITF. However, the expression of all these markers dropped from Day 14 and onwards. CONCLUSIONS Upon exposure of proliferating cells from the adult human PR to differentiating conditions in culture, there is a widespread change in morphology and gene expression, including the upregulation of key retinal markers. However, this upregulation is only transient and decreases after 14 days of differentiation.
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Affiliation(s)
- Erik O Johnsen
- a Center for Eye Research, Department of Ophthalmology , Oslo University Hospital and University of Oslo , Oslo , Norway.,b Norwegian Center for Stem Cell Research , Oslo University Hospital and University of Oslo , Oslo , Norway
| | - Rebecca C Frøen
- a Center for Eye Research, Department of Ophthalmology , Oslo University Hospital and University of Oslo , Oslo , Norway.,b Norwegian Center for Stem Cell Research , Oslo University Hospital and University of Oslo , Oslo , Norway
| | | | - Bjørn Nicolaissen
- a Center for Eye Research, Department of Ophthalmology , Oslo University Hospital and University of Oslo , Oslo , Norway.,b Norwegian Center for Stem Cell Research , Oslo University Hospital and University of Oslo , Oslo , Norway
| | - Goran Petrovski
- a Center for Eye Research, Department of Ophthalmology , Oslo University Hospital and University of Oslo , Oslo , Norway.,b Norwegian Center for Stem Cell Research , Oslo University Hospital and University of Oslo , Oslo , Norway.,d Department of Ophthalmology, Faculty of Medicine , University of Szeged and Stem Cells and Eye Research LaboratorySzeged, Hungary.,e Department of Biochemistry and Molecular Biology , University of Debrecen , Debrecen , Hungary
| | - Morten C Moe
- a Center for Eye Research, Department of Ophthalmology , Oslo University Hospital and University of Oslo , Oslo , Norway.,b Norwegian Center for Stem Cell Research , Oslo University Hospital and University of Oslo , Oslo , Norway
| | - Agate Noer
- a Center for Eye Research, Department of Ophthalmology , Oslo University Hospital and University of Oslo , Oslo , Norway.,b Norwegian Center for Stem Cell Research , Oslo University Hospital and University of Oslo , Oslo , Norway
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23
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Cvekl A, Zhang X. Signaling and Gene Regulatory Networks in Mammalian Lens Development. Trends Genet 2017; 33:677-702. [PMID: 28867048 DOI: 10.1016/j.tig.2017.08.001] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/27/2017] [Accepted: 08/01/2017] [Indexed: 11/16/2022]
Abstract
Ocular lens development represents an advantageous system in which to study regulatory mechanisms governing cell fate decisions, extracellular signaling, cell and tissue organization, and the underlying gene regulatory networks. Spatiotemporally regulated domains of BMP, FGF, and other signaling molecules in late gastrula-early neurula stage embryos generate the border region between the neural plate and non-neural ectoderm from which multiple cell types, including lens progenitor cells, emerge and undergo initial tissue formation. Extracellular signaling and DNA-binding transcription factors govern lens and optic cup morphogenesis. Pax6, c-Maf, Hsf4, Prox1, Sox1, and a few additional factors regulate the expression of the lens structural proteins, the crystallins. Extensive crosstalk between a diverse array of signaling pathways controls the complexity and order of lens morphogenetic processes and lens transparency.
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Affiliation(s)
- Ales Cvekl
- Departments of Genetics and Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
| | - Xin Zhang
- Departments of Ophthalmology, Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.
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24
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Riesenberg AN, Conley KW, Le TT, Brown NL. Separate and coincident expression of Hes1 and Hes5 in the developing mouse eye. Dev Dyn 2017; 247:212-221. [PMID: 28675662 DOI: 10.1002/dvdy.24542] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 06/27/2017] [Accepted: 06/27/2017] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Notch signaling is broadly required during embryogenesis, frequently activating the transcription of two basic helix-loop-helix transcription factors, Hes1 and Hes5. But, it remains unresolved when and where Hes1 and Hes5 act alone or together during development. Here, we analyzed a Hes5-green fluorescent protein (GFP) bacterial artificial chromosome (BAC) transgenic mouse, as a proxy for endogenous Hes5. We directly compared transgenic GFP expression with Hes1, and particular markers of embryonic lens and retina development. RESULTS Hes5-GFP is dynamic within subsets of retinal and lens progenitor cells, and differentiating retinal ganglion neurons, in contrast to Hes1 found in all progenitor cells. In the adult retina, only Müller glia express Hes5-GFP. Finally, Hes5-GFP is up-regulated in Hes1 germline mutants, consistent with previous demonstration that Hes1 suppresses Hes5 transcription. CONCLUSIONS Hes5-GFP BAC transgenic mice are useful for identifying Hes5-expressing cells. Although Hes5-GFP and Hes1 are coexpressed in particular developmental contexts, we also noted cohorts of lens or retinal cells expressing just one factor. The dynamic Hes5-GFP expression pattern, coupled with its derepressed expression in Hes1 mutants, suggests that this transgene contains the relevant cis-regulatory elements that regulate endogenous Hes5 in the mouse lens and retina. Developmental Dynamics 247:212-221, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Amy N Riesenberg
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio
| | - Kevin W Conley
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio
| | - Tien T Le
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio
| | - Nadean L Brown
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio.,Department of Cell Biology & Human Anatomy, University of California Davis, Davis, California
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25
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Rodrigues T, Krawczyk M, Skowronska-Krawczyk D, Matter-Sadzinski L, Matter JM. Delayed neurogenesis with respect to eye growth shapes the pigeon retina for high visual acuity. Development 2016; 143:4701-4712. [PMID: 27836962 DOI: 10.1242/dev.138719] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 11/01/2016] [Indexed: 12/31/2022]
Abstract
The macula and fovea located at the optical centre of the retina make primate visual perception unique among mammals. Our current understanding of retina ontogenesis is primarily based on animal models having no macula and no fovea. However, the pigeon retina and the human macula share a number of structural and functional properties that justify introducing the former as a new model system for retina development. Comparative transcriptome analysis of pigeon and chicken retinas at different embryonic stages reveals that the genetic programmes underlying cell differentiation are postponed in the pigeon until the end of the period of cell proliferation. We show that the late onset of neurogenesis has a profound effect on the developmental patterning of the pigeon retina, which is at odds with the current models of retina development. The uncoupling of tissue growth and neurogenesis is shown to result from the fact that the pigeon retinal epithelium is inhibitory to cell differentiation. The sum of these developmental features allows the pigeon to build a retina that displays the structural and functional traits typical of primate macula and fovea.
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Affiliation(s)
- Tania Rodrigues
- Department of Molecular Biology and Department of Biochemistry, Sciences III, University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Michal Krawczyk
- Shiley Eye Institute, Department of Ophthalmology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Dorota Skowronska-Krawczyk
- Department of Molecular Biology and Department of Biochemistry, Sciences III, University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Lidia Matter-Sadzinski
- Department of Molecular Biology and Department of Biochemistry, Sciences III, University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Jean-Marc Matter
- Department of Molecular Biology and Department of Biochemistry, Sciences III, University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
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26
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Dhanesh SB, Subashini C, James J. Hes1: the maestro in neurogenesis. Cell Mol Life Sci 2016; 73:4019-42. [PMID: 27233500 PMCID: PMC11108451 DOI: 10.1007/s00018-016-2277-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 05/12/2016] [Accepted: 05/12/2016] [Indexed: 10/21/2022]
Abstract
The process of neurogenesis is well orchestrated by the harmony of multiple cues in a spatiotemporal manner. In this review, we focus on how a dynamic gene, Hes1, is involved in neurogenesis with the view of its regulation and functional implications. Initially, we have reviewed the immense functional significance drawn by this maestro during neural development in a context-dependent manner. How this indispensable role of Hes1 in conferring the competency for neural differentiation partly relies on the direct/indirect mode of repression mediated by very specific structural and functional arms of this protein has also been outlined here. We also review the detailed molecular mechanisms behind the well-tuned oscillatory versus sustained expression of this antineurogenic bHLH repressor, which indeed makes it a master gene to implement the elusive task of neural progenitor propensity. Apart from the functional aspects of Hes1, we also discuss the molecular insights into the endogenous regulatory machinery that regulates its expression. Though Hes1 is a classical target of the Notch signaling pathway, we discuss here its differential expression at the molecular, cellular, and/or regional level. Moreover, we describe how its expression is fine-tuned by all possible ways of gene regulation such as epigenetic, transcriptional, post-transcriptional, post-translational, and environmental factors during vertebrate neurogenesis.
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Affiliation(s)
- Sivadasan Bindu Dhanesh
- Neuro Stem Cell Biology Laboratory, Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Thiruvananthapuram, 695 014, Kerala, India
| | - Chandramohan Subashini
- Neuro Stem Cell Biology Laboratory, Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Thiruvananthapuram, 695 014, Kerala, India
| | - Jackson James
- Neuro Stem Cell Biology Laboratory, Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud PO, Thiruvananthapuram, 695 014, Kerala, India.
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27
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Zhou W, He Q, Zhang C, He X, Cui Z, Liu F, Li W. BLOS2 negatively regulates Notch signaling during neural and hematopoietic stem and progenitor cell development. eLife 2016; 5. [PMID: 27719760 PMCID: PMC5094856 DOI: 10.7554/elife.18108] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 10/04/2016] [Indexed: 12/28/2022] Open
Abstract
Notch signaling plays a crucial role in controling the proliferation and differentiation of stem and progenitor cells during embryogenesis or organogenesis, but its regulation is incompletely understood. BLOS2, encoded by the Bloc1s2 gene, is a shared subunit of two lysosomal trafficking complexes, biogenesis of lysosome-related organelles complex-1 (BLOC-1) and BLOC-1-related complex (BORC). Bloc1s2-/- mice were embryonic lethal and exhibited defects in cortical development and hematopoiesis. Loss of BLOS2 resulted in elevated Notch signaling, which consequently increased the proliferation of neural progenitor cells and inhibited neuronal differentiation in cortices. Likewise, ablation of bloc1s2 in zebrafish or mice led to increased hematopoietic stem and progenitor cell production in the aorta-gonad-mesonephros region. BLOS2 physically interacted with Notch1 in endo-lysosomal trafficking of Notch1. Our findings suggest that BLOS2 is a novel negative player in regulating Notch signaling through lysosomal trafficking to control multiple stem and progenitor cell homeostasis in vertebrates.
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Affiliation(s)
- Wenwen Zhou
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Qiuping He
- University of Chinese Academy of Sciences, Beijing, China.,State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Chunxia Zhang
- University of Chinese Academy of Sciences, Beijing, China.,State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xin He
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Zongbin Cui
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Beijing, China
| | - Feng Liu
- University of Chinese Academy of Sciences, Beijing, China.,State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Wei Li
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.,Center for Medical Genetics, Beijing Children's Hospital, Capital Medical University, Beijing, China.,Center of Alzheimer's Disease, Beijing Institute for Brain Disorders, Beijing, China.,MOE Key Laboratory of Major Diseases in Children, Beijing, China.,Beijing Pediatric Research Institute, Beijing, China
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28
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Pathania M, Wang Y, Simirskii VN, Duncan MK. β1-integrin controls cell fate specification in early lens development. Differentiation 2016; 92:133-147. [PMID: 27596755 PMCID: PMC5159248 DOI: 10.1016/j.diff.2016.08.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/05/2016] [Accepted: 08/09/2016] [Indexed: 02/03/2023]
Abstract
Integrins are heterodimeric cell surface molecules that mediate cell-extracellular matrix (ECM) adhesion, ECM assembly, and regulation of both ECM and growth factor induced signaling. However, the developmental context of these diverse functions is not clear. Loss of β1-integrin from the lens vesicle (mouse E10.5) results in abnormal exit of anterior lens epithelial cells (LECs) from the cell cycle and their aberrant elongation toward the presumptive cornea by E12.5. These cells lose expression of LEC markers and initiate expression of the Maf (also known as c-Maf) and Prox1 transcription factors as well as other lens fiber cell markers. β1-integrin null LECs also upregulate the ERK, AKT and Smad1/5/8 phosphorylation indicative of BMP and FGF signaling. By E14.5, β1-integrin null lenses have undergone a complete conversion of all lens epithelial cells into fiber cells. These data suggest that shortly after lens vesicle closure, β1-integrin blocks inappropriate differentiation of the lens epithelium into fibers, potentially by inhibiting BMP and/or FGF receptor activation. Thus, β1-integrin has an important role in fine-tuning the response of the early lens to the gradient of growth factors that regulate lens fiber cell differentiation.
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Affiliation(s)
- Mallika Pathania
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Vladimir N Simirskii
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Melinda K Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
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29
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de Melo J, Clark BS, Blackshaw S. Multiple intrinsic factors act in concert with Lhx2 to direct retinal gliogenesis. Sci Rep 2016; 6:32757. [PMID: 27605455 PMCID: PMC5015061 DOI: 10.1038/srep32757] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 08/15/2016] [Indexed: 12/14/2022] Open
Abstract
Müller glia (MG) are the principal glial cell type in the vertebrate retina. Recent work has identified the LIM homeodomain factor encoding gene Lhx2 as necessary for both Notch signaling and MG differentiation in late-stage retinal progenitor cells (RPCs). However, the extent to which Lhx2 interacts with other intrinsic regulators of MG differentiation is unclear. We investigated this question by investigating the effects of overexpression of multiple transcriptional regulators that are either known or hypothesized to control MG formation, in both wildtype and Lhx2-deficient RPCs. We observe that constitutively elevated Notch signaling, induced by N1ICD electroporation, inhibited gliogenesis in wildtype animals, but rescued MG development in Lhx2-deficient retinas. Electroporation of Nfia promoted the formation of cells with MG-like radial morphology, but did not drive expression of MG molecular markers. Plagl1 and Sox9 did not induce gliogenesis in wildtype animals, but nonetheless activated expression of the Müller marker P27Kip1 in Lhx2-deficient cells. Finally, Sox2, Sox8, and Sox9 promoted amacrine cell formation in Lhx2-deficient cells, but not in wildtype retinas. These findings demonstrate that overexpression of individual gliogenic factors typically regulates only a subset of characteristic MG markers, and that these effects are differentially modulated by Lhx2.
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Affiliation(s)
- Jimmy de Melo
- Johns Hopkins University School of Medicine, Solomon H. Snyder Department of Neuroscience, Baltimore, 21205, USA
| | - Brian S Clark
- Johns Hopkins University School of Medicine, Solomon H. Snyder Department of Neuroscience, Baltimore, 21205, USA
| | - Seth Blackshaw
- Johns Hopkins University School of Medicine, Solomon H. Snyder Department of Neuroscience, Baltimore, 21205, USA.,Johns Hopkins University School of Medicine, Department of Ophthalmology, Baltimore, 21205, USA.,Johns Hopkins University School of Medicine, Department of Neurology, Baltimore, 21205, USA.,Johns Hopkins University School of Medicine, Center for Human Systems Biology, Baltimore, 21205, USA.,Johns Hopkins University School of Medicine, Institute for Cell Engineering, Baltimore, 21205, USA
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30
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Dash S, Siddam AD, Barnum CE, Janga SC, Lachke SA. RNA-binding proteins in eye development and disease: implication of conserved RNA granule components. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:527-57. [PMID: 27133484 DOI: 10.1002/wrna.1355] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 03/21/2016] [Indexed: 01/16/2023]
Abstract
The molecular biology of metazoan eye development is an area of intense investigation. These efforts have led to the surprising recognition that although insect and vertebrate eyes have dramatically different structures, the orthologs or family members of several conserved transcription and signaling regulators such as Pax6, Six3, Prox1, and Bmp4 are commonly required for their development. In contrast, our understanding of posttranscriptional regulation in eye development and disease, particularly regarding the function of RNA-binding proteins (RBPs), is limited. We examine the present knowledge of RBPs in eye development in the insect model Drosophila as well as several vertebrate models such as fish, frog, chicken, and mouse. Interestingly, of the 42 RBPs that have been investigated for their expression or function in vertebrate eye development, 24 (~60%) are recognized in eukaryotic cells as components of RNA granules such as processing bodies, stress granules, or other specialized ribonucleoprotein (RNP) complexes. We discuss the distinct developmental and cellular events that may necessitate potential RBP/RNA granule-associated RNA regulon models to facilitate posttranscriptional control of gene expression in eye morphogenesis. In support of these hypotheses, three RBPs and RNP/RNA granule components Tdrd7, Caprin2, and Stau2 are linked to ocular developmental defects such as congenital cataract, Peters anomaly, and microphthalmia in human patients or animal models. We conclude by discussing the utility of interdisciplinary approaches such as the bioinformatics tool iSyTE (integrated Systems Tool for Eye gene discovery) to prioritize RBPs for deriving posttranscriptional regulatory networks in eye development and disease. WIREs RNA 2016, 7:527-557. doi: 10.1002/wrna.1355 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Soma Dash
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Archana D Siddam
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Carrie E Barnum
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Sarath Chandra Janga
- Department of Biohealth Informatics, School of Informatics and Computing, Indiana University & Purdue University Indianapolis, Indianapolis, IN, USA.,Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Salil A Lachke
- Department of Biological Sciences, University of Delaware, Newark, DE, USA.,Center for Bioinformatics and Computational Biology, University of Delaware, Newark, DE, USA
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31
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Riesenberg AN, Brown NL. Cell autonomous and nonautonomous requirements for Delltalike1 during early mouse retinal neurogenesis. Dev Dyn 2016; 245:631-40. [PMID: 26947267 DOI: 10.1002/dvdy.24402] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 01/14/2016] [Accepted: 02/22/2016] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND In the vertebrate retina, six neuronal and one glial cell class are produced from a common progenitor pool. During neurogenesis, adjacent retinal cells use Notch signaling to maintain a pool of progenitors by blocking particular cells from differentiating prematurely. In mice there are multiple Notch pathway ligands and receptors, but the role(s) of each paralogue during retinal histogenesis remains only partially defined. RESULTS Here we analyzed the cell autonomous and nonautonomous requirements for the Deltalike1(Dll1) ligand during prenatal retinogenesis. We used the α-Cre driver to simultaneously delete a Dll1 conditional allele and activate the Z/EG reporter, then quantified Dll1 mutant phenotypes within and outside of this α-Cre GFP-marked lineage. We found that Dll1 activity is required for Hes1 expression, both autonomously and nonautonomously, but were surprised that retinal ganglion cell differentiation is only blocked cell autonomously. Moreover, Dll1 does not act during cone photoreceptor neurogenesis. Finally, Dll1 mutant adult retinas contained small retinal rosettes and RGC patterning defects but were otherwise normal. CONCLUSIONS Although Dll1 participates in bidirectional (cis + trans) Notch signaling to regulate Hes1 expression, it only acts cell autonomously (in cis) to interpret inhibitory signals from other cells that block RGC neurogenesis. Developmental Dynamics 245:631-640, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Amy N Riesenberg
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio
| | - Nadean L Brown
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, Ohio.,Department of Cell Biology & Human Anatomy, University of California Davis, Davis, California
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32
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33
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Sigulinsky CL, German ML, Leung AM, Clark AM, Yun S, Levine EM. Genetic chimeras reveal the autonomy requirements for Vsx2 in embryonic retinal progenitor cells. Neural Dev 2015; 10:12. [PMID: 25927996 PMCID: PMC4450477 DOI: 10.1186/s13064-015-0039-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 04/14/2015] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Vertebrate retinal development is a complex process, requiring the specification and maintenance of retinal identity, proliferative expansion of retinal progenitor cells (RPCs), and their differentiation into retinal neurons and glia. The homeobox gene Vsx2 is expressed in RPCs and required for the proper execution of this retinal program. However, our understanding of the mechanisms by which Vsx2 does this is still rudimentary. To define the autonomy requirements for Vsx2 in the regulation of RPC properties, we generated chimeric mouse embryos comprised of wild-type and Vsx2-deficient cells. RESULTS We show that Vsx2 maintains retinal identity in part through the cell-autonomous repression of the retinal pigment epithelium determinant Mitf, and that Lhx2 is required cell autonomously for the ectopic Mitf expression in Vsx2-deficient cells. We also found significant cell-nonautonomous contributions to Vsx2-mediated regulation of RPC proliferation, pointing to an important role for Vsx2 in establishing a growth-promoting extracellular environment. Additionally, we report a cell-autonomous requirement for Vsx2 in controlling when neurogenesis is initiated, indicating that Vsx2 is an important mediator of neurogenic competence. Finally, the distribution of wild-type cells shifted away from RPCs and toward retinal ganglion cell precursors in patches of high Vsx2-deficient cell density to potentially compensate for the lack of fated precursors in these areas. CONCLUSIONS Through the generation and analysis of genetic chimeras, we demonstrate that Vsx2 utilizes both cell-autonomous and cell-nonautonomous mechanisms to regulate progenitor properties in the embryonic retina. Importantly, Vsx2's role in regulating Mitf is in part separable from its role in promoting proliferation, and proliferation is excluded as the intrinsic timer that determines when neurogenesis is initiated. These findings highlight the complexity of Vsx2 function during retinal development and provide a framework for identifying the molecular mechanisms mediating these functions.
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Affiliation(s)
- Crystal L Sigulinsky
- Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
- Interdepartmental Program in Neuroscience, University of Utah, 20 North 1900 East, Salt Lake City, UT, 84132, USA.
| | - Massiell L German
- Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Amanda M Leung
- Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
- Department of Neurobiology and Anatomy, University of Utah, 20 North 1900 East, Salt Lake City, UT, 84132, USA.
| | - Anna M Clark
- Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
| | - Sanghee Yun
- Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
- Department of Neurobiology and Anatomy, University of Utah, 20 North 1900 East, Salt Lake City, UT, 84132, USA.
| | - Edward M Levine
- Department of Ophthalmology and Visual Sciences, John A Moran Eye Center, University of Utah, 65 Mario Capecchi Drive, Salt Lake City, UT, 84132, USA.
- Department of Neurobiology and Anatomy, University of Utah, 20 North 1900 East, Salt Lake City, UT, 84132, USA.
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Su YX, Hou CC, Yang WX. Control of hair cell development by molecular pathways involving Atoh1, Hes1 and Hes5. Gene 2014; 558:6-24. [PMID: 25550047 DOI: 10.1016/j.gene.2014.12.054] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 11/23/2014] [Accepted: 12/25/2014] [Indexed: 01/14/2023]
Abstract
Atoh1, Hes1 and Hes5 are crucial for normal inner ear hair cell development. They regulate the expression of each other in a complex network, while they also interact with many other genes and pathways, such as Notch, FGF, SHH, WNT, BMP and RA. This paper summarized molecular pathways that involve Atoh1, Hes1, and Hes5. Some of the pathways and gene regulation mechanisms discussed here were studied in other tissues, yet they might inspire studies in inner ear hair cell development. Thereby, we presented a complex regulatory network involving these three genes, which might be crucial for proliferation and differentiation of inner ear hair cells.
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Affiliation(s)
- Yi-Xun Su
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Cong-Cong Hou
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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35
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Cvekl A, Ashery-Padan R. The cellular and molecular mechanisms of vertebrate lens development. Development 2014; 141:4432-47. [PMID: 25406393 PMCID: PMC4302924 DOI: 10.1242/dev.107953] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The ocular lens is a model system for understanding important aspects of embryonic development, such as cell specification and the spatiotemporally controlled formation of a three-dimensional structure. The lens, which is characterized by transparency, refraction and elasticity, is composed of a bulk mass of fiber cells attached to a sheet of lens epithelium. Although lens induction has been studied for over 100 years, recent findings have revealed a myriad of extracellular signaling pathways and gene regulatory networks, integrated and executed by the transcription factor Pax6, that are required for lens formation in vertebrates. This Review summarizes recent progress in the field, emphasizing the interplay between the diverse regulatory mechanisms employed to form lens progenitor and precursor cells and highlighting novel opportunities to fill gaps in our understanding of lens tissue morphogenesis.
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Affiliation(s)
- Aleš 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
| | - Ruth Ashery-Padan
- Sackler School of Medicine and Sagol School of Neuroscience, Tel-Aviv University, 69978 Ramat Aviv, Tel Aviv, Israel
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36
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Xie BB, Zhang XM, Hashimoto T, Tien AH, Chen A, Ge J, Yang XJ. Differentiation of retinal ganglion cells and photoreceptor precursors from mouse induced pluripotent stem cells carrying an Atoh7/Math5 lineage reporter. PLoS One 2014; 9:e112175. [PMID: 25401462 PMCID: PMC4234374 DOI: 10.1371/journal.pone.0112175] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Accepted: 10/13/2014] [Indexed: 11/18/2022] Open
Abstract
The neural retina is a critical component of the visual system, which provides the majority of sensory input in humans. Various retinal degenerative diseases can result in the permanent loss of retinal neurons, especially the light-sensing photoreceptors and the centrally projecting retinal ganglion cells (RGCs). The replenishment of lost RGCs and the repair of optic nerve damage are particularly challenging, as both RGC specification and their subsequent axonal growth and projection involve complex and precise regulation. To explore the developmental potential of pluripotent stem cell-derived neural progenitors, we have established mouse iPS cells that allow cell lineage tracing of progenitors that have expressed Atoh7/Math5, a bHLH transcription factor required for RGC production. These Atoh7 lineage reporter iPS cells encode Cre to replace one copy of the endogenous Atoh7 gene and a Cre-dependent YFP reporter in the ROSA locus. In addition, they express pluripotent markers and are capable of generating teratomas in vivo. Under anterior neural induction and neurogenic conditions in vitro, the Atoh7-Cre/ROSA-YFP iPS cells differentiate into neurons that co-express various RGC markers and YFP, indicating that these neurons are derived from Atoh7-expressing progenitors. Consistent with previous in vivo cell lineage studies, the Atoh7-Cre/ROSA-YFP iPS cells also give rise to a subset of Crx-positive photoreceptor precursors. Furthermore, inhibition of Notch signaling in the iPSC cultures results in a significant increase of YFP-positive RGCs and photoreceptor precursors. Together, these results show that Atoh7-Cre/ROSA-YFP iPS cells can be used to monitor the development and survival of RGCs and photoreceptors from pluripotent stem cells.
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Affiliation(s)
- Bin-Bin Xie
- Zhong-Shan Ophthalmic Center, Sun Yat-Sen University, Guangzhuo, China
| | - Xiang-Mei Zhang
- Jules Stein Eye Institute, University of California Los Angeles, California, United States of America
| | - Takao Hashimoto
- Jules Stein Eye Institute, University of California Los Angeles, California, United States of America
| | - Amy H. Tien
- Jules Stein Eye Institute, University of California Los Angeles, California, United States of America
| | - Andrew Chen
- Jules Stein Eye Institute, University of California Los Angeles, California, United States of America
| | - Jian Ge
- Zhong-Shan Ophthalmic Center, Sun Yat-Sen University, Guangzhuo, China
| | - Xian-Jie Yang
- Jules Stein Eye Institute, University of California Los Angeles, California, United States of America
- Molecular Biology Institute, University of California Los Angeles, California, United States of America
- * E-mail:
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37
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Maurer KA, Riesenberg AN, Brown NL. Notch signaling differentially regulates Atoh7 and Neurog2 in the distal mouse retina. Development 2014; 141:3243-54. [PMID: 25100656 DOI: 10.1242/dev.106245] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Notch signaling regulates basic helix-loop-helix (bHLH) factors as an evolutionarily conserved module, but the tissue-specific mechanisms are incompletely elucidated. In the mouse retina, bHLH genes Atoh7 and Neurog2 have distinct functions, with Atoh7 regulating retinal competence and Neurog2 required for progression of neurogenesis. These transcription factors are extensively co-expressed, suggesting similar regulation. We directly compared Atoh7 and Neurog2 regulation at the earliest stages of retinal neurogenesis in a broad spectrum of Notch pathway mutants. Notch1 and Rbpj normally block Atoh7 and Neurog2 expression. However, the combined activities of Notch1, Notch3 and Rbpj regulate Neurog2 patterning in the distal retina. Downstream of the Notch complex, we found the Hes1 repressor mediates Atoh7 suppression, but Hes1, Hes3 and Hes5 do not regulate Neurog2 expression. We also tested Notch-mediated regulation of Jag1 and Pax6 in the distal retina, to establish the appropriate context for Neurog2 patterning. We found that Notch1;Notch3 and Rbpj block co-expression of Jag1 and Neurog2, while specifically stimulating Pax6 within an adjacent domain. Our data suggest that Notch signaling controls the overall tempo of retinogenesis, by integrating cell fate specification, the wave of neurogenesis and the developmental status of cells ahead of this wave.
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Affiliation(s)
- Kate A Maurer
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH 45229, USA
| | - Amy N Riesenberg
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH 45229, USA
| | - Nadean L Brown
- Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation, Cincinnati, OH 45229, USA Department of Cell Biology and Human Anatomy, University of California Davis, School of Medicine, Davis, CA 95616, USA
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Kuznetsova AV, Kurinov AM, Aleksandrova MA. Cell models to study regulation of cell transformation in pathologies of retinal pigment epithelium. J Ophthalmol 2014; 2014:801787. [PMID: 25177495 PMCID: PMC4142280 DOI: 10.1155/2014/801787] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 06/16/2014] [Accepted: 06/30/2014] [Indexed: 11/25/2022] Open
Abstract
The retinal pigment epithelium (RPE) plays a key role in the development of many eye diseases leading to visual impairment and even blindness. Cell culture models of pathological changes in the RPE make it possible to study factors responsible for these changes and signaling pathways coordinating cellular and molecular mechanisms of cell interactions under pathological conditions. Moreover, they give an opportunity to reveal target cells and develop effective specific treatment for degenerative and dystrophic diseases of the retina. In this review, data are presented on RPE cell sources for culture models, approaches to RPE cell culturing, phenotypic changes of RPE cells in vitro, the role of signal pathways, and possibilities for their regulation in pathological processes.
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Affiliation(s)
- Alla V. Kuznetsova
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow 119334, Russia
| | - Alexander M. Kurinov
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow 119334, Russia
| | - Maria A. Aleksandrova
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow 119334, Russia
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Sinn R, Peravali R, Heermann S, Wittbrodt J. Differential responsiveness of distinct retinal domains to Atoh7. Mech Dev 2014; 133:218-29. [PMID: 25151399 PMCID: PMC4232737 DOI: 10.1016/j.mod.2014.08.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 07/24/2014] [Accepted: 08/11/2014] [Indexed: 02/03/2023]
Abstract
During vertebrate eye development retinal progenitor cells (RPCs) differentiate into all neural cell types of the retina. Retinal ganglion cells (RGCs) represent the first cell type to be generated. For their development, Atoh7, a basic Helix Loop Helix (bHLH) transcription factor is crucial. Atoh7 loss of function results in a massive reduction or even a total loss of RGCs. However, inconsistent results have been obtained in atoh7 gain of function experiments with respect to ganglion cell genesis, implying that the effect of Atoh7 is likely to be dependent on the competence state of the RPC. In this study we addressed the differential susceptibilities of early RPCs to Atoh7 in vivo, using medaka. Unexpectedly, we observed a largely normal development of the dorsal retina, although atoh7 was precociously expressed. However, the development of the retina close to the optic nerve head (part of the ventral retina) was disturbed severely. Photoreceptors were largely absent and the Müller glia cell number was reduced significantly. The majority of cells in this domain were ganglion cells and the abnormal development of this area affected the closure of the optic fissure resulting in coloboma.
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Affiliation(s)
- Rebecca Sinn
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany; Hartmut Hoffmann-Berling International Graduate School (HBIGS), Heidelberg, Germany
| | - Ravindra Peravali
- Institute of Toxicology and Genetics (ITG), Karlsruhe Institute of Technology, Germany
| | - Stephan Heermann
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany; Institute for Anatomy and Cell Biology, Dept. of Molecular Embryology, University Freiburg, Freiburg, Germany
| | - Joachim Wittbrodt
- Centre for Organismal Studies, Heidelberg University, Heidelberg, Germany
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Sarode B, Nowell CS, Ihm J, Kostic C, Arsenijevic Y, Moulin AP, Schorderet DF, Beermann F, Radtke F. Notch signaling in the pigmented epithelium of the anterior eye segment promotes ciliary body development at the expense of iris formation. Pigment Cell Melanoma Res 2014; 27:580-9. [DOI: 10.1111/pcmr.12236] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 03/12/2014] [Indexed: 11/27/2022]
Affiliation(s)
- Bhushan Sarode
- School of Life Science; Ecole Polytechnique Fédérale de Lausanne (EPFL); Lausanne Switzerland
- Swiss Institute for Experimental Cancer Research (ISREC); Lausanne Switzerland
| | - Craig S. Nowell
- School of Life Science; Ecole Polytechnique Fédérale de Lausanne (EPFL); Lausanne Switzerland
- Swiss Institute for Experimental Cancer Research (ISREC); Lausanne Switzerland
| | - JongEun Ihm
- School of Life Science; Ecole Polytechnique Fédérale de Lausanne (EPFL); Lausanne Switzerland
| | - Corinne Kostic
- Unit of Gene Therapy and Stem Cell Biology; Jules-Gonin Eye Hospital; University of Lausanne; Lausanne Switzerland
- Eye Pathology Laboratory; Jules-Gonin Eye Hospital; University of Lausanne; Lausanne Switzerland
| | - Yvan Arsenijevic
- Unit of Gene Therapy and Stem Cell Biology; Jules-Gonin Eye Hospital; University of Lausanne; Lausanne Switzerland
- Eye Pathology Laboratory; Jules-Gonin Eye Hospital; University of Lausanne; Lausanne Switzerland
| | - Alexandre P. Moulin
- Eye Pathology Laboratory; Jules-Gonin Eye Hospital; University of Lausanne; Lausanne Switzerland
| | - Daniel F. Schorderet
- School of Life Science; Ecole Polytechnique Fédérale de Lausanne (EPFL); Lausanne Switzerland
- Eye Pathology Laboratory; Jules-Gonin Eye Hospital; University of Lausanne; Lausanne Switzerland
- IRO - Institute for Research in Ophthalmology; Sion Switzerland
| | - Friedrich Beermann
- School of Life Science; Ecole Polytechnique Fédérale de Lausanne (EPFL); Lausanne Switzerland
- Swiss Institute for Experimental Cancer Research (ISREC); Lausanne Switzerland
| | - Freddy Radtke
- School of Life Science; Ecole Polytechnique Fédérale de Lausanne (EPFL); Lausanne Switzerland
- Swiss Institute for Experimental Cancer Research (ISREC); Lausanne Switzerland
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41
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Klimova L, Kozmik Z. Stage-dependent requirement of neuroretinal Pax6 for lens and retina development. Development 2014; 141:1292-302. [PMID: 24523460 DOI: 10.1242/dev.098822] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The physical contact of optic vesicle with head surface ectoderm is an initial event triggering eye morphogenesis. This interaction leads to lens specification followed by coordinated invagination of the lens placode and optic vesicle, resulting in formation of the lens, retina and retinal pigmented epithelium. Although the role of Pax6 in early lens development has been well documented, its role in optic vesicle neuroepithelium and early retinal progenitors is poorly understood. Here we show that conditional inactivation of Pax6 at distinct time points of mouse neuroretina development has a different impact on early eye morphogenesis. When Pax6 is eliminated in the retina at E10.5 using an mRx-Cre transgene, after a sufficient contact between the optic vesicle and surface ectoderm has occurred, the lens develops normally but the pool of retinal progenitor cells gradually fails to expand. Furthermore, a normal differentiation program is not initiated, leading to almost complete disappearance of the retina after birth. By contrast, when Pax6 was inactivated at the onset of contact between the optic vesicle and surface ectoderm in Pax6(Sey/flox) embryos, expression of lens-specific genes was not initiated and neither the lens nor the retina formed. Our data show that Pax6 in the optic vesicle is important not only for proper retina development, but also for lens formation in a non-cell-autonomous manner.
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Affiliation(s)
- Lucie Klimova
- Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Videnska 1083, 14420 Prague 4, Czech Republic
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42
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Cavalheiro GR, Matos-Rodrigues GE, Gomes AL, Rodrigues PMG, Martins RAP. c-Myc regulates cell proliferation during lens development. PLoS One 2014; 9:e87182. [PMID: 24503550 PMCID: PMC3913586 DOI: 10.1371/journal.pone.0087182] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 12/20/2013] [Indexed: 12/20/2022] Open
Abstract
Myc protooncogenes play important roles in the regulation of cell proliferation, growth, differentiation and survival during development. In various developing organs, c-myc has been shown to control the expression of cell cycle regulators and its misregulated expression is detected in many human tumors. Here, we show that c-myc gene (Myc) is highly expressed in developing mouse lens. Targeted deletion of c-myc gene from head surface ectoderm dramatically impaired ocular organogenesis, resulting in severe microphtalmia, defective anterior segment development, formation of a lens stalk and/or aphakia. In particular, lenses lacking c-myc presented thinner epithelial cell layer and growth impairment that was detectable soon after its inactivation. Defective development of c-myc-null lens was not caused by increased cell death of lens progenitor cells. Instead, c-myc loss reduced cell proliferation, what was associated with an ectopic expression of Prox1 and p27Kip1 proteins within epithelial cells. Interestingly, a sharp decrease in the expression of the forkhead box transcription factor Foxe3 was also observed following c-myc inactivation. These data represent the first description of the physiological roles played by a Myc family member in mouse lens development. Our findings support the conclusion that c-myc regulates the proliferation of lens epithelial cells in vivo and may, directly or indirectly, modulate the expression of classical cell cycle regulators in developing mouse lens.
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Affiliation(s)
- Gabriel R. Cavalheiro
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabriel E. Matos-Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Anielle L. Gomes
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo M. G. Rodrigues
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo A. P. Martins
- Programa de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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43
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Yip HK. Retinal stem cells and regeneration of vision system. Anat Rec (Hoboken) 2013; 297:137-60. [PMID: 24293400 DOI: 10.1002/ar.22800] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 09/13/2013] [Indexed: 12/14/2022]
Abstract
The vertebrate retina is a well-characterized model for studying neurogenesis. Retinal neurons and glia are generated in a conserved order from a pool of mutlipotent progenitor cells. During retinal development, retinal stem/progenitor cells (RPC) change their competency over time under the influence of intrinsic (such as transcriptional factors) and extrinsic factors (such as growth factors). In this review, we summarize the roles of these factors, together with the understanding of the signaling pathways that regulate eye development. The information about the interactions between intrinsic and extrinsic factors for retinal cell fate specification is useful to regenerate specific retinal neurons from RPCs. Recent studies have identified RPCs in the retina, which may have important implications in health and disease. Despite the recent advances in stem cell biology, our understanding of many aspects of RPCs in the eye remains limited. PRCs are present in the developing eye of all vertebrates and remain active in lower vertebrates throughout life. In mammals, however, PRCs are quiescent and exhibit very little activity and thus have low capacity for retinal regeneration. A number of different cellular sources of RPCs have been identified in the vertebrate retina. These include PRCs at the retinal margin, pigmented cells in the ciliary body, iris, and retinal pigment epithelium, and Müller cells within the retina. Because PRCs can be isolated and expanded from immature and mature eyes, it is possible now to study these cells in culture and after transplantation in the degenerated retinal tissue. We also examine current knowledge of intrinsic RPCs, and human embryonic stems and induced pluripotent stem cells as potential sources for cell transplant therapy to regenerate the diseased retina.
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Affiliation(s)
- Henry K Yip
- Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Adminstrative Region, People's Republic of China; Research Center of Heart, Brain, Hormone and Healthy Aging, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Adminstrative Region, People's Republic of China; State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Pokfulam, Hong Kong Special Adminstrative Region, People's Republic of China
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44
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Dixit R, Tachibana N, Touahri Y, Zinyk D, Logan C, Schuurmans C. Gene expression is dynamically regulated in retinal progenitor cells prior to and during overt cellular differentiation. Gene Expr Patterns 2013; 14:42-54. [PMID: 24148613 DOI: 10.1016/j.gep.2013.10.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 10/11/2013] [Accepted: 10/11/2013] [Indexed: 12/27/2022]
Abstract
The retina is comprised of one glial and six neuronal populations that are generated from a multipotent pool of retinal progenitor cells (RPCs) during development. To give rise to these different cell types, RPCs undergo temporal identity transitions, displaying distinct gene expression profiles at different stages of differentiation. Little, however, is known about temporal differences in RPC identities prior to the onset of overt cellular differentiation, during the period when a retinal identity is gradually acquired. Here we examined the sequential onset of expression of regional markers (i.e., homeodomain transcription factors) and cell fate determinants (i.e., basic-helix-loop-helix transcription factors and neurogenic genes) in RPCs from the earliest appearance of a morphologically-distinct retina. By performing a comparative analysis of the expression of a panel of 27 homeodomain, basic-helix-loop-helix and Notch pathway genes between embryonic day (E) 8.75 and postnatal day (P) 9, we identified six distinct RPC molecular profiles. At E8.75, the earliest stage assayed, murine RPCs expressed five homeodomain genes and a single neurogenic gene (Pax6, Six3, Six6, Rx, Otx2, Hes1). This early gene expression profile was remarkably similar to that of 'early' RPCs in the amphibian ciliary marginal zone (CMZ), where RPCs are compartmentalised according to developmental stage, and homologs of Pax6, Six3 and Rx are expressed in the 'early' stem cell zone. As development proceeds, expression of additional homeodomain, bHLH and neurogenic genes was gradually initiated in murine RPCs, allowing distinct genetic profiles to also be defined at E9.5, E10.5, E12.5, E15.5 and P0. In addition, RPCs in the postnatal ciliary margin, where retinal stem cells are retained throughout life, displayed a unique molecular signature, expressing all of the early-onset genes as well as several late-onset markers, indicative of a 'mixed' temporal identity. Taken together, the identification of temporal differences in gene expression in mammalian RPCs during pre-neurogenic developmental stages leads to new insights into how regional identities are progressively acquired during development, while comparisons at later stages highlight the dynamic nature of gene expression in temporally distinct RPC pools.
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Affiliation(s)
- Rajiv Dixit
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada.
| | - Nobuhiko Tachibana
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Yacine Touahri
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Dawn Zinyk
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada
| | - Cairine Logan
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Carol Schuurmans
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada.
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45
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El Yakoubi W, Borday C, Hamdache J, Parain K, Tran HT, Vleminckx K, Perron M, Locker M. Hes4 controls proliferative properties of neural stem cells during retinal ontogenesis. Stem Cells 2013; 30:2784-95. [PMID: 22969013 PMCID: PMC3549485 DOI: 10.1002/stem.1231] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 08/08/2012] [Indexed: 11/22/2022]
Abstract
The retina of fish and amphibian contains genuine neural stem cells located at the most peripheral edge of the ciliary marginal zone (CMZ). However, their cell-of-origin as well as the mechanisms that sustain their maintenance during development are presently unknown. We identified Hes4 (previously named XHairy2), a gene encoding a bHLH-O transcriptional repressor, as a stem cell-specific marker of the Xenopus CMZ that is positively regulated by the canonical Wnt pathway and negatively by Hedgehog signaling. We found that during retinogenesis, Hes4 labels a small territory, located first at the pigmented epithelium (RPE)/neural retina (NR) border and later in the retinal margin, that likely gives rise to adult retinal stem cells. We next addressed whether Hes4 might impart this cell subpopulation with retinal stem cell features: inhibited RPE or NR differentiation programs, continuous proliferation, and slow cell cycle speed. We could indeed show that Hes4 overexpression cell autonomously prevents retinal precursor cells from commitment toward retinal fates and maintains them in a proliferative state. Besides, our data highlight for the first time that Hes4 may also constitute a crucial regulator of cell cycle kinetics. Hes4 gain of function indeed significantly slows down cell division, mainly through the lengthening of G1 phase. As a whole, we propose that Hes4 maintains particular stemness features in a cellular cohort dedicated to constitute the adult retinal stem cell pool, by keeping it in an undifferentiated and slowly proliferative state along embryonic retinogenesis. Stem Cells 2012;30:2784–2795
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Gordon PJ, Yun S, Clark AM, Monuki ES, Murtaugh LC, Levine EM. Lhx2 balances progenitor maintenance with neurogenic output and promotes competence state progression in the developing retina. J Neurosci 2013; 33:12197-207. [PMID: 23884928 PMCID: PMC3721834 DOI: 10.1523/jneurosci.1494-13.2013] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 05/29/2013] [Accepted: 06/13/2013] [Indexed: 11/21/2022] Open
Abstract
The LIM-Homeodomain transcription factor Lhx2 is an essential organizer of early eye development and is subsequently expressed in retinal progenitor cells (RPCs). To determine its requirement in RPCs, we performed a temporal series of conditional inactivations in mice with the early RPC driver Pax6 α-Cre and the tamoxifen-inducible Hes1(CreERT2) driver. Deletion of Lhx2 caused a significant reduction of the progenitor population and a corresponding increase in neurogenesis. Precursor fate choice correlated with the time of inactivation; early and late inactivation led to the overproduction of retinal ganglion cells (RGCs) and rod photoreceptors, respectively. In each case, however, the overproduction was selective, occurring at the expense of other cell types and indicating a role for Lhx2 in generating cell type diversity. RPCs that persisted in the absence of Lhx2 continued to generate RGC precursors beyond their normal production window, suggesting that Lhx2 facilitates a transition in competence state. These results identify Lhx2 as a key regulator of RPC properties that contribute to the ordered production of multiple cell types during retinal tissue formation.
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Affiliation(s)
- Patrick J. Gordon
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center
- Interdepartmental Program in Neuroscience, and
| | - Sanghee Yun
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center
| | - Anna M. Clark
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center
| | - Edwin S. Monuki
- Department of Pathology and Laboratory Medicine, University of California, Irvine, California 92697
| | - L. Charles Murtaugh
- Department of Human Genetics, University of Utah, Salt Lake City, Utah 84132, and
| | - Edward M. Levine
- Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center
- Department of Neurobiology and Anatomy
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47
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Venters SJ, Mikawa T, Hyer J. Central and peripheral retina arise through distinct developmental paths. PLoS One 2013; 8:e61422. [PMID: 23613848 PMCID: PMC3628928 DOI: 10.1371/journal.pone.0061422] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 03/10/2013] [Indexed: 12/21/2022] Open
Abstract
In the mature eye, three distinct tissue fates, retina, ciliary body, and iris, arrange with a strict linear organization along the central (back) to peripheral (front) axis. The establishment of this topographical relationship within the optic vesicle is not well understood. We use a targeted vital labeling strategy to test the derivation of mature eye tissues from the optic vesicle of the chick embryo. Fate mapping uncovers two distinct origins of the neural retina. Contrary to expectations, the central neural retina has a discrete origin within the posterior optic vesicle. The peripheral retina derives from the distal optic vesicle, sharing a common origin with more peripheral tissue fates. This study identifies for the first time two distinct retinal sub-domains, central and peripheral, which arise during embryogenesis. Identification of these discrete retinal compartments provides a framework for understanding functional and disease processes throughout retinal tissue.
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Affiliation(s)
- Sara J. Venters
- Department of Neurosurgery, University of California San Francisco, San Francisco, California, United States of America
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, California, United States of America
| | - Takashi Mikawa
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, California, United States of America
| | - Jeanette Hyer
- Department of Neurosurgery, University of California San Francisco, San Francisco, California, United States of America
- Department of Ophthalmology, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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48
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Chiodini F, Matter-Sadzinski L, Rodrigues T, Skowronska-Krawczyk D, Brodier L, Schaad O, Bauer C, Ballivet M, Matter JM. A positive feedback loop between ATOH7 and a Notch effector regulates cell-cycle progression and neurogenesis in the retina. Cell Rep 2013; 3:796-807. [PMID: 23434507 DOI: 10.1016/j.celrep.2013.01.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 01/02/2013] [Accepted: 01/31/2013] [Indexed: 01/24/2023] Open
Abstract
The HES proteins are known Notch effectors and have long been recognized as important in inhibiting neuronal differentiation. However, the roles that they play in the specification of neuronal fate remain largely unknown. Here, we show that in the differentiating retinal epithelium, the proneural protein ATOH7 (ATH5) is required for the activation of the transcription of the Hes5.3 gene before the penultimate mitosis of progenitor cells. We further show that the HES5.3 protein slows down the cell-cycle progression of Atoh7-expressing cells, thereby establishing conditions for Atoh7 to reach a high level of expression in S phase and induce neuronal differentiation prior to the ultimate mitosis. Our study uncovers how a proneural protein recruits a protein known to be a component of the Notch signaling pathway in order to regulate the transition between an initial phase of selection among uncommitted progenitors and a later phase committing the selected progenitors to neuronal differentiation.
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Affiliation(s)
- Florence Chiodini
- Department of Biochemistry, Sciences II, University of Geneva, 1211 Geneva, Switzerland
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49
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Osakada F, Takahashi M. Stem Cells in the Developing and Adult Nervous System. Regen Med 2013. [DOI: 10.1007/978-94-007-5690-8_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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50
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Zhu MY, Gasperowicz M, Chow RL. The expression of NOTCH2, HES1 and SOX9 during mouse retinal development. Gene Expr Patterns 2012; 13:78-83. [PMID: 23277114 DOI: 10.1016/j.gep.2012.12.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 12/08/2012] [Accepted: 12/21/2012] [Indexed: 11/28/2022]
Abstract
Notch signaling is an important regulator of both developmental and post-developmental processes. In the developing retina, Notch1 is required for the maintenance of retinal progenitor cells and for inhibiting photoreceptor cell fate, while Notch3 is required for inhibiting ganglion cell fate. Here we used immunolabeling coupled with a knock-in reporter approach to obtain a detailed spatiotemporal expression pattern of Notch2 during mouse retinal development. Although previous in situ hybridization studies did not reveal appreciable levels of Notch2 in the developing retina, we detected NOTCH2 protein and reporter expression in early embryonic retinal progenitors that also expressed the Notch downstream gene, HES1. In the postnatal retina, NOTCH2, as well as the Notch downstream genes, HES1 and SOX9, were detected in VSX2/Cyclin D1/SOX2-expressing cells in the postnatal retina, and in the mature retina NOTCH2 was most abundant in Müller glia. Our findings indicate a potential role for Notch2 in the developing and mature retina.
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Affiliation(s)
- Min-Yan Zhu
- Department of Biology, University of Victoria, Victoria, BC, Canada, V8W 3N5
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