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Bery A, Bagchi U, Bergen AA, Felder-Schmittbuhl MP. Circadian clocks, retinogenesis and ocular health in vertebrates: new molecular insights. Dev Biol 2022; 484:40-56. [DOI: 10.1016/j.ydbio.2022.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 01/21/2022] [Accepted: 02/01/2022] [Indexed: 12/22/2022]
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LIM Homeobox 4 (lhx4) regulates retinal neural differentiation and visual function in zebrafish. Sci Rep 2021; 11:1977. [PMID: 33479361 PMCID: PMC7820405 DOI: 10.1038/s41598-021-81211-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 01/04/2021] [Indexed: 01/29/2023] Open
Abstract
LIM homeobox 4 (LHX4) is expressed in the photoreceptors (PRs) of the outer nuclear layer (ONL) and bipolar cells (BCs) of the inner nuclear layer (INL) in mouse and chicken retina. It regulates the subtype-specific development of rod BCs and cone BCs in the mouse retina. However, no report has been published on its expression and function in the zebrafish retina. In this study, we assessed the expression of Lhx4 using in situ hybridization (ISH) technique and explored its role in zebrafish (Danio rerio) retinal development via morpholino (MO) technology. We found that the expression of lhx4 in the zebrafish retina begins 48 h post-fertilization (hpf) and is continuously expressed in the ONL and INL. A zebrafish model constructed with lhx4 knockdown in the eyes through vivo-MO revealed that: lhx4 knockdown inhibits the differentiation of Parvalbumin+ amacrine cells (ACs) and Rhodopsin+ rod photoreceptors (RPs), enhances the expression of visual system homeobox 2 (vsx2); and damages the responses of zebrafish to light stimulus, without affecting the differentiation of OFF-BCs and rod BCs, and apoptosis in the retina. These findings reveal that lhx4 regulates neural differentiation in the retina and visual function during zebrafish embryonic development.
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3
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Single-Cell Analysis of Human Retina Identifies Evolutionarily Conserved and Species-Specific Mechanisms Controlling Development. Dev Cell 2020; 53:473-491.e9. [PMID: 32386599 DOI: 10.1016/j.devcel.2020.04.009] [Citation(s) in RCA: 131] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/05/2020] [Accepted: 04/10/2020] [Indexed: 01/08/2023]
Abstract
The development of single-cell RNA sequencing (scRNA-seq) has allowed high-resolution analysis of cell-type diversity and transcriptional networks controlling cell-fate specification. To identify the transcriptional networks governing human retinal development, we performed scRNA-seq analysis on 16 time points from developing retina as well as four early stages of retinal organoid differentiation. We identified evolutionarily conserved patterns of gene expression during retinal progenitor maturation and specification of all seven major retinal cell types. Furthermore, we identified gene-expression differences between developing macula and periphery and between distinct populations of horizontal cells. We also identified species-specific patterns of gene expression during human and mouse retinal development. Finally, we identified an unexpected role for ATOH7 expression in regulation of photoreceptor specification during late retinogenesis. These results provide a roadmap to future studies of human retinal development and may help guide the design of cell-based therapies for treating retinal dystrophies.
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Blixt MKE, Konjusha D, Ring H, Hallböök F. Zinc finger gene nolz1 regulates the formation of retinal progenitor cells and suppresses the Lim3/Lhx3 phenotype of retinal bipolar cells in chicken retina. Dev Dyn 2017; 247:630-641. [PMID: 29139167 DOI: 10.1002/dvdy.24607] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 09/29/2017] [Accepted: 10/17/2017] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The zinc-finger transcription factor Nolz1 regulates spinal cord neuron development by interacting with the transcription factors Isl1, Lim1, and Lim3, which are also important for photoreceptors, horizontal and bipolar cells during retinal development. We, therefore, studied Nolz1 during retinal development. RESULTS Nolz1 expression was seen in two waves during development: one early (peak at embryonic day 3-4.5) in retinal progenitors and one late (embryonic day 8) in newly differentiated cells in the inner nuclear layer. Overexpression and knockdown showed that Nolz1 decreases proliferation and stimulates cell cycle withdrawal in retinal progenitors with effects on the generation of retinal ganglion cells, photoreceptors, and horizontal cells without triggering apoptosis. Overexpression of Nolz1 gave more p27 positive cells. Sustained overexpression of Nolz1 in the retina gave fewer Lim3/Lhx3 bipolar cells. CONCLUSIONS We conclude that Nolz1 has multiple functions during development and suggest a mechanism in which Nolz1 initially regulates the proliferation state of the retinal progenitor cells and then acts as a repressor that suppresses the Lim3/Lhx3 bipolar cell phenotype at the time of bipolar cell differentiation. Developmental Dynamics 247:630-641, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Maria K E Blixt
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Dardan Konjusha
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Henrik Ring
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Finn Hallböök
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
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Stenfelt S, Blixt MKE, All-Ericsson C, Hallböök F, Boije H. Heterogeneity in retinoblastoma: a tale of molecules and models. Clin Transl Med 2017; 6:42. [PMID: 29124525 PMCID: PMC5680409 DOI: 10.1186/s40169-017-0173-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 10/26/2017] [Indexed: 12/13/2022] Open
Abstract
Retinoblastoma, an intraocular pediatric cancer, develops in the embryonic retina following biallelic loss of RB1. However, there is a wide range of genetic and epigenetic changes that can affect RB1 resulting in different clinical outcomes. In addition, other transformations, such as MYCN amplification, generate particularly aggressive tumors, which may or may not be RB1 independent. Recognizing the cellular characteristics required for tumor development, by identifying the elusive cell-of-origin for retinoblastoma, would help us understand the development of these tumors. In this review we summarize the heterogeneity reported in retinoblastoma on a molecular, cellular and tissue level. We also discuss the challenging heterogeneity in current retinoblastoma models and suggest future platforms that could contribute to improved understanding of tumor initiation, progression and metastasis in retinoblastoma, which may ultimately lead to more patient-specific treatments.
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Affiliation(s)
- Sonya Stenfelt
- Department of Neuroscience, Uppsala University, 75124, Uppsala, Sweden
| | - Maria K E Blixt
- Department of Neuroscience, Uppsala University, 75124, Uppsala, Sweden
| | | | - Finn Hallböök
- Department of Neuroscience, Uppsala University, 75124, Uppsala, Sweden
| | - Henrik Boije
- Department of Neuroscience, Uppsala University, 75124, Uppsala, Sweden.
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6
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Laboissonniere LA, Martin GM, Goetz JJ, Bi R, Pope B, Weinand K, Ellson L, Fru D, Lee M, Wester AK, Liu P, Trimarchi JM. Single cell transcriptome profiling of developing chick retinal cells. J Comp Neurol 2017; 525:2735-2781. [PMID: 28510275 DOI: 10.1002/cne.24241] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 04/07/2017] [Accepted: 05/08/2017] [Indexed: 02/06/2023]
Abstract
The vertebrate retina is a specialized photosensitive tissue comprised of six neuronal and one glial cell types, each of which develops in prescribed proportions at overlapping timepoints from a common progenitor pool. While each of these cells has a specific function contributing to proper vision in the mature animal, their differential representation in the retina as well as the presence of distinctive cellular subtypes makes identifying the transcriptomic signatures that lead to each retinal cell's fate determination and development challenging. We have analyzed transcriptomes from individual cells isolated from the chick retina throughout retinogenesis. While we focused our efforts on the retinal ganglion cells, our transcriptomes of developing chick cells also contained representation from multiple retinal cell types, including photoreceptors and interneurons at different stages of development. Most interesting was the identification of transcriptomes from individual mixed lineage progenitor cells in the chick as these cells offer a window into the cell fate decision-making process. Taken together, these data sets will enable us to uncover the most critical genes acting in the steps of cell fate determination and early differentiation of various retinal cell types.
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Affiliation(s)
- Lauren A Laboissonniere
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Gregory M Martin
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Jillian J Goetz
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Ran Bi
- Department of Statistics, 2117 Snedecor Hall, Iowa State University, Ames, Iowa, 50011
| | - Brock Pope
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Kallie Weinand
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Laura Ellson
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Diane Fru
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Miranda Lee
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Andrea K Wester
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
| | - Peng Liu
- Department of Statistics, 2117 Snedecor Hall, Iowa State University, Ames, Iowa, 50011
| | - Jeffrey M Trimarchi
- Department of Genetics, Development and Cell Biology, 2114 Molecular Biology, Iowa State University, Ames, Iowa, 50011
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Boije H, Shirazi Fard S, Edqvist PH, Hallböök F. Horizontal Cells, the Odd Ones Out in the Retina, Give Insights into Development and Disease. Front Neuroanat 2016; 10:77. [PMID: 27486389 PMCID: PMC4949263 DOI: 10.3389/fnana.2016.00077] [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: 04/12/2016] [Accepted: 06/21/2016] [Indexed: 01/03/2023] Open
Abstract
Thorough investigation of a neuronal population can help reveal key aspects regarding the nervous system and its development. The retinal horizontal cells have several extraordinary features making them particularly interesting for addressing questions regarding fate assignment and subtype specification. In this review we discuss and summarize data concerning the formation and diversity of horizontal cells, how morphology is correlated to molecular markers, and how fate assignment separates the horizontal lineage from the lineages of other retinal cell types. We discuss the novel and unique features of the final cell cycle of horizontal cell progenitors and how they may relate to retinoblastoma carcinogenesis.
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Affiliation(s)
- Henrik Boije
- Department of Neuroscience, Uppsala University Uppsala, Sweden
| | | | - Per-Henrik Edqvist
- Department of Immunology, Genetics and Pathology, Uppsala University Uppsala, Sweden
| | - Finn Hallböök
- Department of Neuroscience, Uppsala University Uppsala, Sweden
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Martín-Partido G, Francisco-Morcillo J. The role of Islet-1 in cell specification, differentiation, and maintenance of phenotypes in the vertebrate neural retina. Neural Regen Res 2016; 10:1951-2. [PMID: 26889183 PMCID: PMC4730819 DOI: 10.4103/1673-5374.165301] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Affiliation(s)
- Gervasio Martín-Partido
- Departamento de Biología Celular, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
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Dorn T, Goedel A, Lam JT, Haas J, Tian Q, Herrmann F, Bundschu K, Dobreva G, Schiemann M, Dirschinger R, Guo Y, Kühl SJ, Sinnecker D, Lipp P, Laugwitz KL, Kühl M, Moretti A. Direct nkx2-5 transcriptional repression of isl1 controls cardiomyocyte subtype identity. Stem Cells 2016; 33:1113-29. [PMID: 25524439 PMCID: PMC6750130 DOI: 10.1002/stem.1923] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 10/29/2014] [Accepted: 11/08/2014] [Indexed: 12/31/2022]
Abstract
During cardiogenesis, most myocytes arise from cardiac progenitors expressing the transcription factors Isl1 and Nkx2-5. Here, we show that a direct repression of Isl1 by Nkx2-5 is necessary for proper development of the ventricular myocardial lineage. Overexpression of Nkx2-5 in mouse embryonic stem cells (ESCs) delayed specification of cardiac progenitors and inhibited expression of Isl1 and its downstream targets in Isl1(+) precursors. Embryos deficient for Nkx2-5 in the Isl1(+) lineage failed to downregulate Isl1 protein in cardiomyocytes of the heart tube. We demonstrated that Nkx2-5 directly binds to an Isl1 enhancer and represses Isl1 transcriptional activity. Furthermore, we showed that overexpression of Isl1 does not prevent cardiac differentiation of ESCs and in Xenopus laevis embryos. Instead, it leads to enhanced specification of cardiac progenitors, earlier cardiac differentiation, and increased cardiomyocyte number. Functional and molecular characterization of Isl1-overexpressing cardiomyocytes revealed higher beating frequencies in both ESC-derived contracting areas and Xenopus Isl1-gain-of-function hearts, which associated with upregulation of nodal-specific genes and downregulation of transcripts of working myocardium. Immunocytochemistry of cardiomyocyte lineage-specific markers demonstrated a reduction of ventricular cells and an increase of cells expressing the pacemaker channel Hcn4. Finally, optical action potential imaging of single cardiomyocytes combined with pharmacological approaches proved that Isl1 overexpression in ESCs resulted in normally electrophysiologically functional cells, highly enriched in the nodal subtype at the expense of the ventricular lineage. Our findings provide an Isl1/Nkx2-5-mediated mechanism that coordinately regulates the specification of cardiac progenitors toward the different myocardial lineages and ensures proper acquisition of myocyte subtype identity.
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Affiliation(s)
- Tatjana Dorn
- I. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität München, Munich, Germany
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Boije H, Rulands S, Dudczig S, Simons BD, Harris WA. The Independent Probabilistic Firing of Transcription Factors: A Paradigm for Clonal Variability in the Zebrafish Retina. Dev Cell 2015; 34:532-43. [PMID: 26343455 PMCID: PMC4572358 DOI: 10.1016/j.devcel.2015.08.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 06/29/2015] [Accepted: 08/13/2015] [Indexed: 01/31/2023]
Abstract
Early retinal progenitor cells (RPCs) in vertebrates produce lineages that vary greatly both in terms of cell number and fate composition, yet how this variability is achieved remains unknown. One possibility is that these RPCs are individually distinct and that each gives rise to a unique lineage. Another is that stochastic mechanisms play upon the determinative machinery of equipotent early RPCs to drive clonal variability. Here we show that a simple model, based on the independent firing of key fate-influencing transcription factors, can quantitatively account for the intrinsic clonal variance in the zebrafish retina and predict the distributions of neuronal cell types in clones where one or more of these fates are made unavailable. A simple quantitative model can explain clonal variability in the retina This model is based on the firing probabilities of key transcription factors These probabilities are shown to be largely independent of each other The environment has only a minor effect on these probabilities
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Affiliation(s)
- Henrik Boije
- Department of Physiology, Development and Neuroscience, Cambridge University, Cambridge CB2 3DY, UK; Department of Neuroscience, Uppsala University, 751 24 Uppsala, Sweden
| | - Steffen Rulands
- Department of Physics, Cambridge University, Cambridge CB3 0HE, UK
| | - Stefanie Dudczig
- Department of Physiology, Development and Neuroscience, Cambridge University, Cambridge CB2 3DY, UK
| | | | - William A Harris
- Department of Physiology, Development and Neuroscience, Cambridge University, Cambridge CB2 3DY, UK.
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11
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Expression and function of the LIM-homeodomain transcription factor Islet-1 in the developing and mature vertebrate retina. Exp Eye Res 2015; 138:22-31. [DOI: 10.1016/j.exer.2015.06.021] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 06/24/2015] [Accepted: 06/25/2015] [Indexed: 11/19/2022]
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12
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Ascl1 as a novel player in the Ptf1a transcriptional network for GABAergic cell specification in the retina. PLoS One 2014; 9:e92113. [PMID: 24643195 PMCID: PMC3958475 DOI: 10.1371/journal.pone.0092113] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/17/2014] [Indexed: 11/19/2022] Open
Abstract
In contrast with the wealth of data involving bHLH and homeodomain transcription factors in retinal cell type determination, the molecular bases underlying neurotransmitter subtype specification is far less understood. Using both gain and loss of function analyses in Xenopus, we investigated the putative implication of the bHLH factor Ascl1 in this process. We found that in addition to its previously characterized proneural function, Ascl1 also contributes to the specification of the GABAergic phenotype. We showed that it is necessary for retinal GABAergic cell genesis and sufficient in overexpression experiments to bias a subset of retinal precursor cells towards a GABAergic fate. We also analysed the relationships between Ascl1 and a set of other bHLH factors using an in vivo ectopic neurogenic assay. We demonstrated that Ascl1 has unique features as a GABAergic inducer and is epistatic over factors endowed with glutamatergic potentialities such as Neurog2, NeuroD1 or Atoh7. This functional specificity is conferred by the basic DNA binding domain of Ascl1 and involves a specific genetic network, distinct from that underlying its previously demonstrated effects on catecholaminergic differentiation. Our data show that GABAergic inducing activity of Ascl1 requires the direct transcriptional regulation of Ptf1a, providing therefore a new piece of the network governing neurotransmitter subtype specification during retinogenesis.
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Abstract
Isl1 is a LIM-homeodomain transcription factor that is critical in the development and differentiation of multiple tissues. In the mouse inner ear, Isl1 is expressed in the prosensory region of otocyst, in young hair cells and supporting cells, and is no longer expressed in postnatal auditory hair cells. To evaluate how continuous Isl1 expression in postnatal hair cells affects hair cell development and cochlear function, we created a transgenic mouse model in which the Pou4f3 promoter drives Isl1 overexpression specifically in hair cells. Isl1 overexpressing hair cells develop normally, as seen by morphology and cochlear functions (auditory brainstem response and otoacoustic emissions). As the mice aged to 17 months, wild-type (WT) controls showed the progressive threshold elevation and outer hair cell loss characteristic of the age-related hearing loss (ARHL) in the background strain (C57BL/6J). In contrast, the Isl1 transgenic mice showed significantly less threshold elevation with survival of hair cells. Further, the Isl1 overexpression protected the ear from noise-induced hearing loss (NIHL): both ABR threshold shifts and hair cell death were significantly reduced when compared with WT littermates. Our model suggests a common mechanism underlying ARHL and NIHL, and provides evidence that hair cell-specific Isl1 expression can promote hair cell survival and therefore minimize the hearing impairment that normally occurs with aging and/or acoustic overexposure.
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14
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Islet-1 immunoreactivity in the developing retina of Xenopus laevis. ScientificWorldJournal 2013; 2013:740420. [PMID: 24348185 PMCID: PMC3844241 DOI: 10.1155/2013/740420] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 09/22/2013] [Indexed: 01/09/2023] Open
Abstract
The LIM-homeodomain transcription factor Islet1 (Isl1) has been widely used as a marker of neuronal differentiation in the developing visual system of different classes of vertebrates, including mammals, birds, reptiles, and fish. In the present study, we analyzed the spatial and temporal distribution of Isl1-immunoreactive cells during Xenopus laevis retinal development and its relation to the formation of the retinal layers, and in combination with different markers of cell differentiation. The earliest Isl1 expression appeared at St29-30 in the cell nuclei of sparse differentiating neuroblasts located in the vitreal surface of the undifferentiated retina. At St35-36, abundant Isl1-positive cells accumulated at the vitreal surface of the neuroepithelium. As development proceeded and through the postmetamorphic juveniles, Isl1 expression was identified in subpopulations of ganglion cells and in subsets of amacrine, bipolar, and horizontal cells. These data together suggest a possible role for Isl1 in the early differentiation and maintenance of different retinal cell types, and Isl1 can serve as a specific molecular marker for the study of retinal cell specification in X. laevis.
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Islam MM, Li Y, Luo H, Xiang M, Cai L. Meis1 regulates Foxn4 expression during retinal progenitor cell differentiation. Biol Open 2013; 2:1125-36. [PMID: 24244849 PMCID: PMC3828759 DOI: 10.1242/bio.20132279] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 08/12/2013] [Indexed: 12/20/2022] Open
Abstract
The transcription factor forkhead box N4 (Foxn4) is a key regulator in a variety of biological processes during development. In particular, Foxn4 plays an essential role in the genesis of horizontal and amacrine neurons from neural progenitors in the vertebrate retina. Although the functions of Foxn4 have been well established, the transcriptional regulation of Foxn4 expression during progenitor cell differentiation remains unclear. Here, we report that an evolutionarily conserved 129 bp noncoding DNA fragment (Foxn4CR4.2 or CR4.2), located ∼26 kb upstream of Foxn4 transcription start site, functions as a cis-element for Foxn4 regulation. CR4.2 directs gene expression in Foxn4-positive cells, primarily in progenitors, differentiating horizontal and amacrine cells. We further determined that the gene regulatory activity of CR4.2 is modulated by Meis1 binding motif, which is bound and activated by Meis1 transcription factor. Deletion of the Meis1 binding motif or knockdown of Meis1 expression abolishes the gene regulatory activity of CR4.2. In addition, knockdown of Meis1 expression diminishes the endogenous Foxn4 expression and affects cell lineage development. Together, we demonstrate that CR4.2 and its interacting Meis1 transcription factor play important roles in regulating Foxn4 expression during early retinogenesis. These findings provide new insights into molecular mechanisms that govern gene regulation in retinal progenitors and specific cell lineage development.
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Affiliation(s)
- Mohammed M Islam
- Department of Biomedical Engineering, Rutgers University , 599 Taylor Road, Piscataway, NJ 08854 , USA ; Present address: Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
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Inoue J, Ueda Y, Bando T, Mito T, Noji S, Ohuchi H. The expression of LIM-homeobox genes,Lhx1andLhx5,in the forebrain is essential for neural retina differentiation. Dev Growth Differ 2013; 55:668-75. [DOI: 10.1111/dgd.12074] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Revised: 07/22/2013] [Accepted: 07/22/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Junji Inoue
- Department of Cytology and Histology; Okayama University Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; 2-5-1 Shikata-cho; Okayama; 700-8558; Japan
| | - Yuuki Ueda
- Department of Life Systems; Institute of Technology and Science; The University of Tokushima Graduate School; 2-1 Minami-Josanjima-cho; Tokushima; 770-8506; Japan
| | - Tetsuya Bando
- Department of Cytology and Histology; Okayama University Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; 2-5-1 Shikata-cho; Okayama; 700-8558; Japan
| | - Taro Mito
- Department of Life Systems; Institute of Technology and Science; The University of Tokushima Graduate School; 2-1 Minami-Josanjima-cho; Tokushima; 770-8506; Japan
| | - Sumihare Noji
- Department of Life Systems; Institute of Technology and Science; The University of Tokushima Graduate School; 2-1 Minami-Josanjima-cho; Tokushima; 770-8506; Japan
| | - Hideyo Ohuchi
- Department of Cytology and Histology; Okayama University Graduate School of Medicine; Dentistry and Pharmaceutical Sciences; 2-5-1 Shikata-cho; Okayama; 700-8558; Japan
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Shirazi Fard S, Jarrin M, Boije H, Fillon V, All-Eriksson C, Hallböök F. Heterogenic final cell cycle by chicken retinal Lim1 horizontal progenitor cells leads to heteroploid cells with a remaining replicated genome. PLoS One 2013; 8:e59133. [PMID: 23527113 PMCID: PMC3602602 DOI: 10.1371/journal.pone.0059133] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Accepted: 02/13/2013] [Indexed: 12/24/2022] Open
Abstract
Retinal progenitor cells undergo apical mitoses during the process of interkinetic nuclear migration and newly generated post-mitotic neurons migrate to their prospective retinal layer. Whereas this is valid for most types of retinal neurons, chicken horizontal cells are generated by delayed non-apical mitoses from dedicated progenitors. The regulation of such final cell cycle is not well understood and we have studied how Lim1 expressing horizontal progenitor cells (HPCs) exit the cell cycle. We have used markers for S- and G2/M-phase in combination with markers for cell cycle regulators Rb1, cyclin B1, cdc25C and p27Kip1 to characterise the final cell cycle of HPCs. The results show that Lim1+ HPCs are heterogenic with regards to when and during what phase they leave the final cell cycle. Not all horizontal cells were generated by a non-apical (basal) mitosis; instead, the HPCs exhibited three different behaviours during the final cell cycle. Thirty-five percent of the Lim1+ horizontal cells was estimated to be generated by non-apical mitoses. The other horizontal cells were either generated by an interkinetic nuclear migration with an apical mitosis or by a cell cycle with an S-phase that was not followed by any mitosis. Such cells remain with replicated DNA and may be regarded as somatic heteroploids. The observed heterogeneity of the final cell cycle was also seen in the expression of Rb1, cyclin B1, cdc25C and p27Kip1. Phosphorylated Rb1-Ser608 was restricted to the Lim1+ cells that entered S-phase while cyclin B1 and cdc25C were exclusively expressed in HPCs having a basal mitosis. Only HPCs that leave the cell cycle after an apical mitosis expressed p27Kip1. We speculate that the cell cycle heterogeneity with formation of heteroploid cells may present a cellular context that contributes to the suggested propensity of these cells to generate cancer when the retinoblastoma gene is mutated.
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Affiliation(s)
| | - Miguel Jarrin
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Henrik Boije
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
| | - Valerie Fillon
- Laboratoire de Génétique Cellulaire, Institut National de la Recherche Agronomique, Castanet-Tolosan, France
| | | | - Finn Hallböök
- Department of Neuroscience, Uppsala University, Uppsala, Sweden
- * E-mail:
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Kawaue T, Okamoto M, Matsuyo A, Inoue J, Ueda Y, Tomonari S, Noji S, Ohuchi H. Lhx1 in the proximal region of the optic vesicle permits neural retina development in the chicken. Biol Open 2012; 1:1083-93. [PMID: 23213388 PMCID: PMC3507191 DOI: 10.1242/bio.20121396] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 07/17/2012] [Indexed: 11/25/2022] Open
Abstract
How the eye forms has been one of the fundamental issues in developmental biology. The retinal anlage first appears as the optic vesicle (OV) evaginating from the forebrain. Subsequently, its distal portion invaginates to form the two-walled optic cup, which develops into the outer pigmented and inner neurosensory layers of the retina. Recent work has shown that this optic-cup morphogenesis proceeds as a self-organizing activity without any extrinsic molecules. However, intrinsic factors that regulate this process have not been elucidated. Here we show that a LIM-homeobox gene, Lhx1, normally expressed in the proximal region of the nascent OV, induces a second neurosensory retina formation from the outer pigmented retina when overexpressed in the chicken OV. Lhx2, another LIM-homeobox gene supposed to be involved in early OV formation, could not substitute this function of Lhx1, while Lhx5, closely related to Lhx1, could replace it. Conversely, knockdown of Lhx1 expression by RNA interference resulted in the formation of a small or pigmented vesicle. These results suggest that the proximal region demarcated by Lhx1 expression permits OV development, eventually dividing the two retinal domains.
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Affiliation(s)
- Takumi Kawaue
- Department of Life Systems, Institute of Technology and Science, The University of Tokushima Graduate School , 2-1 Minami-Josanjima-cho, Tokushima 770-8506 , Japan
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Ye L, Evans J, Gargett CE. Lim1/LIM1 is expressed in developing and adult mouse and human endometrium. Histochem Cell Biol 2012; 137:527-36. [DOI: 10.1007/s00418-011-0909-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2011] [Indexed: 01/12/2023]
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Lelièvre EC, Lek M, Boije H, Houille-Vernes L, Brajeul V, Slembrouck A, Roger JE, Sahel JA, Matter JM, Sennlaub F, Hallböök F, Goureau O, Guillonneau X. Ptf1a/Rbpj complex inhibits ganglion cell fate and drives the specification of all horizontal cell subtypes in the chick retina. Dev Biol 2011; 358:296-308. [PMID: 21839069 DOI: 10.1016/j.ydbio.2011.07.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 07/19/2011] [Accepted: 07/25/2011] [Indexed: 11/18/2022]
Abstract
During development, progenitor cells of the retina give rise to six principal classes of neurons and the Müller glial cells found within the adult retina. The pancreas transcription factor 1 subunit a (Ptf1a) encodes a basic-helix-loop-helix transcription factor necessary for the specification of horizontal cells and the majority of amacrine cell subtypes in the mouse retina. The Ptf1a-regulated genes and the regulation of Ptf1a activity by transcription cofactors during retinogenesis have been poorly investigated. Using a retrovirus-mediated gene transfer approach, we reported that Ptf1a was sufficient to promote the fates of amacrine and horizontal cells from retinal progenitors and inhibit retinal ganglion cell and photoreceptor differentiation in the chick retina. Both GABAergic H1 and non-GABAergic H3 horizontal cells were induced following the forced expression of Ptf1a. We describe Ptf1a as a strong, negative regulator of Atoh7 expression. Furthermore, the Rbpj-interacting domains of Ptf1a protein were required for its effects on cell fate specification. Together, these data provide a novel insight into the molecular basis of Ptf1a activity on early cell specification in the chick retina.
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Affiliation(s)
- E C Lelièvre
- Centre de Recherche des Cordeliers, INSERM UMR S872, 75006 Paris, France
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A regulatory domain is required for Foxn4 activity during retinogenesis. J Mol Neurosci 2011; 46:315-23. [PMID: 21701787 DOI: 10.1007/s12031-011-9585-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 06/14/2011] [Indexed: 01/24/2023]
Abstract
Foxn4, a member of the N-family forkhead transcription factors, controls fate decision in mouse retina and spinal cord as well as in zebrafish heart. Analysis of Foxn4 amino acid sequence revealed the presence of a region homologous to the activation domain of its close relative Foxn1 in between C-terminal amino acids 402 and 455 of Foxn4 protein. The requirement of Foxn4 putative activation domain remains to be elucidated. Using a gain-of function approach in rat and chick retinal explants, we report that deletion of Foxn4 putative activation domain results in a complete loss of its activity during retinogenesis. Target promoter transcription assay indicates that this domain is critical for Foxn4 transcriptional regulatory properties in vitro. Accordingly, in chick retinal explants, this domain is required for proper regulation of target retinogenic factors expression by Foxn4. Thus, our study demonstrates that the domain between amino acids 402 and 455 is necessary for Foxn4 transcriptional activity both in vitro and in the retina.
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Zhang X, Serb JM, Greenlee MHW. Mouse retinal development: a dark horse model for systems biology research. Bioinform Biol Insights 2011; 5:99-113. [PMID: 21698072 PMCID: PMC3118678 DOI: 10.4137/bbi.s6930] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The developing retina is an excellent model to study cellular fate determination and differentiation in the context of a complex tissue. Over the last decade, many basic principles and key genes that underlie these processes have been experimentally identified. In this review, we construct network models to summarize known gene interactions that underlie determination and fundamentally affect differentiation of each retinal cell type. These networks can act as a scaffold to assemble subsequent discoveries. In addition, these summary networks provide a rational segue to systems biology approaches necessary to understand the many events leading to appropriate cellular determination and differentiation in the developing retina and other complex tissues.
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Affiliation(s)
- Xia Zhang
- Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
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Abstract
Neuronal populations display conspicuous variability in their size among individuals, but the genetic sources of this variation are largely undefined. We demonstrate a large and highly heritable variation in neuron number within the mouse retina, affecting a critical population of interneurons, the horizontal cells. Variation in the size of this population maps to the distal end of chromosome (Chr) 13, a region homologous to human Chr 5q11.1-11.2. This region contains two genes known to modulate retinal cell number. Using conditional knock-out mice, we demonstrate that one of these genes, the LIM homeodomain gene Islet-1 (Isl1), plays a role in regulating horizontal cell number. Genetic differences in Isl1 expression are high during the period of horizontal cell production, and cis-regulation of Isl1 expression within the retina is demonstrated directly. We identify a single nucleotide polymorphism in the 5' UTR of Isl1 that creates an E-box sequence as a candidate causal variant contributing to this variation in horizontal cell number.
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Doh ST, Hao H, Loh SC, Patel T, Tawil HY, Chen DK, Pashkova A, Shen A, Wang H, Cai L. Analysis of retinal cell development in chick embryo by immunohistochemistry and in ovo electroporation techniques. BMC DEVELOPMENTAL BIOLOGY 2010; 10:8. [PMID: 20089190 PMCID: PMC2822752 DOI: 10.1186/1471-213x-10-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Accepted: 01/20/2010] [Indexed: 01/08/2023]
Abstract
Background Retinal cell development has been extensively investigated; however, the current knowledge of dynamic morphological and molecular changes is not yet complete. Results This study was aimed at revealing the dynamic morphological and molecular changes in retinal cell development during the embryonic stages using a new method of targeted retinal injection, in ovo electroporation, and immunohistochemistry techniques. A plasmid DNA that expresses the green fluorescent protein (GFP) as a marker was delivered into the sub-retinal space to transfect the chick retinal stem/progenitor cells at embryonic day 3 (E3) or E4 with the aid of pulses of electric current. The transfected retinal tissues were analyzed at various stages during chick development from near the start of neurogenesis at E4 to near the end of neurogenesis at E18. The expression of GFP allowed for clear visualization of cell morphologies and retinal laminar locations for the indication of retinal cell identity. Immunohistochemistry using cell type-specific markers (e.g., Visinin, Xap-1, Lim1+2, Pkcα, NeuN, Pax6, Brn3a, Vimentin, etc.) allowed further confirmation of retinal cell types. The composition of retinal cell types was then determined over time by counting the number of GFP-expressing cells observed with morphological characteristics specific to the various retinal cell types. Conclusion The new method of retinal injection and electroporation at E3 - E4 allows the visualization of all retinal cell types, including the late-born neurons, e.g., bipolar cells at a level of single cells, which has been difficult with a conventional method with injection and electroporation at E1.5. Based on data collected from analyses of cell morphology, laminar locations in the retina, immunohistochemistry, and cell counts of GFP-expressing cells, the time-line and dynamic morphological and molecular changes of retinal cell development were determined. These data provide more complete information on retinal cell development, and they can serve as a reference for the investigations in normal retinal development and diseases.
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Affiliation(s)
- Sung Tae Doh
- Department of Biomedical Engineering, Rutgers University, 599 Taylor Road, Piscataway, NJ 08854, USA
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Poché RA, Reese BE. Retinal horizontal cells: challenging paradigms of neural development and cancer biology. Development 2009; 136:2141-51. [PMID: 19502480 DOI: 10.1242/dev.033175] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A group of retinal interneurons known as horizontal cells has recently been shown to exhibit a variety of unique biological properties, as compared with other nerve cells, that challenge many long-standing assumptions in the fields of neural development and cancer biology. These features include their unusual migratory behavior, their unique morphological plasticity, and their propensity to divide at a relatively late stage during development. Here, we review these novel features, discuss their relevance for other cell types, outline open questions in our understanding of horizontal cell development and consider their implications.
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Affiliation(s)
- Ross A Poché
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.
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