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Lebœuf M, Vargas-Abonce SE, Pezé-Hedsieck E, Dupont E, Jimenez-Alonso L, Moya KL, Prochiantz A. ENGRAILED-1 transcription factor has a paracrine neurotrophic activity on adult spinal α-motoneurons. EMBO Rep 2023; 24:e56525. [PMID: 37534581 PMCID: PMC10398658 DOI: 10.15252/embr.202256525] [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: 11/22/2022] [Revised: 05/30/2023] [Accepted: 06/01/2023] [Indexed: 08/04/2023] Open
Abstract
Several homeoprotein transcription factors transfer between cells and regulate gene expression, protein translation, and chromatin organization in recipient cells. ENGRAILED-1 is one such homeoprotein expressed in spinal V1 interneurons that synapse on α-motoneurons. Neutralizing extracellular ENGRAILED-1 by expressing a secreted single-chain antibody blocks its capture by spinal motoneurons resulting in α-motoneuron loss and limb weakness. A similar but stronger phenotype is observed in the Engrailed-1 heterozygote mouse, confirming that ENGRAILED-1 exerts a paracrine neurotrophic activity on spinal cord α-motoneurons. Intrathecal injection of ENGRAILED-1 leads to its specific internalization by spinal motoneurons and has long-lasting protective effects against neurodegeneration and weakness. Midbrain dopaminergic neurons express Engrailed-1 and, similarly to spinal cord α-motoneurons, degenerate in the heterozygote. We identify genes expressed in spinal cord motoneurons whose expression changes in mouse Engrailed-1 heterozygote midbrain neurons. Among these, p62/SQSTM1 shows increased expression during aging in spinal cord motoneurons in the Engrailed-1 heterozygote and upon extracellular ENGRAILED-1 neutralization. We conclude that ENGRAILED-1 might regulate motoneuron aging and has non-cell-autonomous neurotrophic activity.
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Affiliation(s)
- Mélanie Lebœuf
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
- BrainEver SAS, Paris, France
| | - Stephanie E Vargas-Abonce
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
- BrainEver SAS, Paris, France
| | - Eugénie Pezé-Hedsieck
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Edmond Dupont
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | | | - Kenneth L Moya
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Alain Prochiantz
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
- BrainEver SAS, Paris, France
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2
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Leung RF, George AM, Roussel EM, Faux MC, Wigle JT, Eisenstat DD. Genetic Regulation of Vertebrate Forebrain Development by Homeobox Genes. Front Neurosci 2022; 16:843794. [PMID: 35546872 PMCID: PMC9081933 DOI: 10.3389/fnins.2022.843794] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 03/14/2022] [Indexed: 01/19/2023] Open
Abstract
Forebrain development in vertebrates is regulated by transcription factors encoded by homeobox, bHLH and forkhead gene families throughout the progressive and overlapping stages of neural induction and patterning, regional specification and generation of neurons and glia from central nervous system (CNS) progenitor cells. Moreover, cell fate decisions, differentiation and migration of these committed CNS progenitors are controlled by the gene regulatory networks that are regulated by various homeodomain-containing transcription factors, including but not limited to those of the Pax (paired), Nkx, Otx (orthodenticle), Gsx/Gsh (genetic screened), and Dlx (distal-less) homeobox gene families. This comprehensive review outlines the integral role of key homeobox transcription factors and their target genes on forebrain development, focused primarily on the telencephalon. Furthermore, links of these transcription factors to human diseases, such as neurodevelopmental disorders and brain tumors are provided.
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Affiliation(s)
- Ryan F. Leung
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
| | - Ankita M. George
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
| | - Enola M. Roussel
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
| | - Maree C. Faux
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
- Department of Surgery, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Jeffrey T. Wigle
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB, Canada
| | - David D. Eisenstat
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
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3
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Grodstein J, Levin M. A Computational Approach to Explaining Bioelectrically Induced Persistent, Stochastic Changes of Axial Polarity in Planarian Regeneration. Bioelectricity 2022. [DOI: 10.1089/bioe.2021.0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Joel Grodstein
- Department of Electrical and Computer Engineering, Tufts University, Medford, Massachusetts, USA
| | - Michael Levin
- Allen Discovery Center at Tufts University, Medford, Massachusetts, USA
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, Massachusetts, USA
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4
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Bridoux L, Gofflot F, Rezsohazy R. HOX Protein Activity Regulation by Cellular Localization. J Dev Biol 2021; 9:jdb9040056. [PMID: 34940503 PMCID: PMC8707151 DOI: 10.3390/jdb9040056] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/29/2021] [Accepted: 12/02/2021] [Indexed: 12/18/2022] Open
Abstract
While the functions of HOX genes have been and remain extensively studied in distinct model organisms from flies to mice, the molecular biology of HOX proteins remains poorly documented. In particular, the mechanisms involved in regulating the activity of HOX proteins have been poorly investigated. Nonetheless, based on data available from other well-characterized transcription factors, it can be assumed that HOX protein activity must be finely tuned in a cell-type-specific manner and in response to defined environmental cues. Indeed, records in protein–protein interaction databases or entries in post-translational modification registries clearly support that HOX proteins are the targets of multiple layers of regulation at the protein level. In this context, we review here what has been reported and what can be inferred about how the activities of HOX proteins are regulated by their intracellular distribution.
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5
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Moya KL, Ibad RT. OTX2 signaling in retinal dysfunction, degeneration and regeneration. Neural Regen Res 2021; 16:2002-2003. [PMID: 33642378 PMCID: PMC8343299 DOI: 10.4103/1673-5374.308094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/21/2020] [Accepted: 12/18/2020] [Indexed: 11/04/2022] Open
Affiliation(s)
- Kenneth. L. Moya
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Paris, France
- Univ. Lille, CNRS, UMR 8523 -PhLAM -Physique des Lasers Atomes et Molécules, F-59000 Lille, France
| | - Raoul Torero Ibad
- Univ. Lille, CNRS, UMR 8523 -PhLAM -Physique des Lasers Atomes et Molécules, F-59000 Lille, France
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6
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Latta L, Figueiredo FC, Ashery-Padan R, Collinson JM, Daniels J, Ferrari S, Szentmáry N, Solá S, Shalom-Feuerstein R, Lako M, Xapelli S, Aberdam D, Lagali N. Pathophysiology of aniridia-associated keratopathy: Developmental aspects and unanswered questions. Ocul Surf 2021; 22:245-266. [PMID: 34520870 DOI: 10.1016/j.jtos.2021.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 07/19/2021] [Accepted: 09/08/2021] [Indexed: 12/13/2022]
Abstract
Aniridia, a rare congenital disease, is often characterized by a progressive, pronounced limbal insufficiency and ocular surface pathology termed aniridia-associated keratopathy (AAK). Due to the characteristics of AAK and its bilateral nature, clinical management is challenging and complicated by the multiple coexisting ocular and systemic morbidities in aniridia. Although it is primarily assumed that AAK originates from a congenital limbal stem cell deficiency, in recent years AAK and its pathogenesis has been questioned in the light of new evidence and a refined understanding of ocular development and the biology of limbal stem cells (LSCs) and their niche. Here, by consolidating and comparing the latest clinical and preclinical evidence, we discuss key unanswered questions regarding ocular developmental aspects crucial to AAK. We also highlight hypotheses on the potential role of LSCs and the ocular surface microenvironment in AAK. The insights thus gained lead to a greater appreciation for the role of developmental and cellular processes in the emergence of AAK. They also highlight areas for future research to enable a deeper understanding of aniridia, and thereby the potential to develop new treatments for this rare but blinding ocular surface disease.
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Affiliation(s)
- L Latta
- Dr. Rolf. M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany; Department of Ophthalmology, Saarland University Medical Center, Homburg, Saar, Germany.
| | - F C Figueiredo
- Department of Ophthalmology, Royal Victoria Infirmary, Newcastle Upon Tyne, United Kingdom
| | - R Ashery-Padan
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, 69978, Israel
| | - J M Collinson
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen, AB25 2ZD, United Kingdom
| | - J Daniels
- Cells for Sight, UCL Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
| | - S Ferrari
- The Veneto Eye Bank Foundation, Venice, Italy
| | - N Szentmáry
- Dr. Rolf. M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany
| | - S Solá
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - R Shalom-Feuerstein
- Department of Genetics and Developmental Biology, The Rappaport Faculty of Medicine and Research Institute, Technion - Israel Institute of Technology, Haifa, Israel
| | - M Lako
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - S Xapelli
- Instituto Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - D Aberdam
- Centre de Recherche des Cordeliers, INSERM U1138, Team 17, France; Université de Paris, 75006, Paris, France.
| | - N Lagali
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden; Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway.
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7
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Di Nardo AA, Joliot A, Prochiantz A. Homeoprotein transduction in neurodevelopment and physiopathology. SCIENCE ADVANCES 2020; 6:6/44/eabc6374. [PMID: 33115744 PMCID: PMC7608782 DOI: 10.1126/sciadv.abc6374] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 09/11/2020] [Indexed: 05/28/2023]
Abstract
Homeoproteins were originally identified for embryonic cell-autonomous transcription activity, but they also have non-cell-autonomous activity owing to transfer between cells. This Review discusses transfer mechanisms and focuses on some established functions, such as neurodevelopmental regulation of axon guidance, and postnatal critical periods of brain plasticity that affect sensory processing and cognition. Homeoproteins are present across all eukaryotes, and intercellular transfer occurs in plants and animals. Proposed functions have evolutionary relevance, such as morphogenetic activity and sexual exchange during the mating of unicellular eukaryotes, while others have physiopathological relevance, such as regulation of mood and cognition by influencing brain compartmentalization, connectivity, and plasticity. There are more than 250 known homeoproteins with conserved transfer domains, suggesting that this is a common mode of signal transduction but with many undiscovered functions.
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Affiliation(s)
- Ariel A Di Nardo
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, INSERM U1050, PSL University, Labex MemoLife, 75005 Paris, France.
| | - Alain Joliot
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, INSERM U1050, PSL University, Labex MemoLife, 75005 Paris, France
| | - Alain Prochiantz
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241, INSERM U1050, PSL University, Labex MemoLife, 75005 Paris, France.
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8
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OTX2 Non-Cell Autonomous Activity Regulates Inner Retinal Function. eNeuro 2020; 7:ENEURO.0012-19.2020. [PMID: 32737182 PMCID: PMC7477954 DOI: 10.1523/eneuro.0012-19.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/19/2020] [Accepted: 05/05/2020] [Indexed: 12/11/2022] Open
Abstract
OTX2 is a homeoprotein transcription factor expressed in photoreceptors and bipolar cells in the retina. OTX2, like many other homeoproteins, transfers between cells and exerts non-cell autonomous effects such as promoting the survival of retinal ganglion cells that do not express the protein. Here we used a genetic approach to target extracellular OTX2 in the retina by conditional expression of a secreted single-chain anti-OTX2 antibody. Compared with control mice, the expression of this antibody by parvalbumin-expressing neurons in the retina is followed by a reduction in visual acuity in 1-month-old mice with no alteration of the retinal structure or cell type number or aspect. The a-waves and b-waves measured by electroretinogram were also indistinguishable from those of control mice, suggesting no functional deficit of photoreceptors and bipolar cells. Mice expressing the OTX2-neutralizing antibody did show a significant doubling in the flicker amplitude and a reduction in oscillatory potential, consistent with a change in inner retinal function. Our results show that interfering in vivo with OTX2 non-cell autonomous activity in the postnatal retina leads to an alteration in inner retinal cell functions and causes a deficit in visual acuity.
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9
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Gbx1 and Gbx2 Are Essential for Normal Patterning and Development of Interneurons and Motor Neurons in the Embryonic Spinal Cord. J Dev Biol 2020; 8:jdb8020009. [PMID: 32244588 PMCID: PMC7345146 DOI: 10.3390/jdb8020009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/01/2020] [Accepted: 03/26/2020] [Indexed: 12/17/2022] Open
Abstract
The molecular mechanisms regulating neurogenesis involve the control of gene expression by transcription factors. Gbx1 and Gbx2, two members of the Gbx family of homeodomain-containing transcription factors, are known for their essential roles in central nervous system development. The expression domains of mouse Gbx1 and Gbx2 include regions of the forebrain, anterior hindbrain, and spinal cord. In the spinal cord, Gbx1 and Gbx2 are expressed in PAX2+ interneurons of the dorsal horn and ventral motor neuron progenitors. Based on their shared domains of expression and instances of overlap, we investigated the functional relationship between Gbx family members in the developing spinal cord using Gbx1−/−, Gbx2−/−, and Gbx1−/−/Gbx2−/− embryos. In situ hybridization analyses of embryonic spinal cords show upregulation of Gbx2 expression in Gbx1−/− embryos and upregulation of Gbx1 expression in Gbx2−/− embryos. Additionally, our data demonstrate that Gbx genes regulate development of a subset of PAX2+ dorsal inhibitory interneurons. While we observe no difference in overall proliferative status of the developing ependymal layer, expansion of proliferative cells into the anatomically defined mantle zone occurs in Gbx mutants. Lastly, our data shows a marked increase in apoptotic cell death in the ventral spinal cord of Gbx mutants during mid-embryonic stages. While our studies reveal that both members of the Gbx gene family are involved in development of subsets of PAX2+ dorsal interneurons and survival of ventral motor neurons, Gbx1 and Gbx2 are not sufficient to genetically compensate for the loss of one another. Thus, our studies provide novel insight to the relationship harbored between Gbx1 and Gbx2 in spinal cord development.
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10
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Aguilar G, Vigano MA, Affolter M, Matsuda S. Reflections on the use of protein binders to study protein function in developmental biology. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2019; 8:e356. [PMID: 31265212 PMCID: PMC6851689 DOI: 10.1002/wdev.356] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 06/03/2019] [Accepted: 06/04/2019] [Indexed: 02/01/2023]
Abstract
Studies in the field of developmental biology aim to unravel how a fertilized egg develops into an adult organism and how proteins and other macromolecules work together during this process. With regard to protein function, most of the developmental studies have used genetic and RNA interference approaches, combined with biochemical analyses, to reach this goal. However, there always remains much room for interpretation on how a given protein functions, because proteins work together with many other molecules in complex regulatory networks and it is not easy to reveal the function of one given protein without affecting the networks. Likewise, it has remained difficult to experimentally challenge and/or validate the proposed concepts derived from mutant analyses without tools that directly manipulate protein function in a predictable manner. Recently, synthetic tools based on protein binders such as scFvs, nanobodies, DARPins, and others have been applied in developmental biology to directly manipulate target proteins in a predicted manner. Although such tools would have a great impact in filling the gap of knowledge between mutant phenotypes and protein functions, careful investigations are required when applying functionalized protein binders to fundamental questions in developmental biology. In this review, we first summarize how protein binders have been used in the field, and then reflect on possible guidelines for applying such tools to study protein functions in developmental biology. This article is categorized under: Technologies > Analysis of Proteins Establishment of Spatial and Temporal Patterns > Gradients Invertebrate Organogenesis > Flies.
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11
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Kaddour H, Coppola E, Di Nardo AA, Le Poupon C, Mailly P, Wizenmann A, Volovitch M, Prochiantz A, Pierani A. Extracellular Pax6 Regulates Tangential Cajal–Retzius Cell Migration in the Developing Mouse Neocortex. Cereb Cortex 2019; 30:465-475. [DOI: 10.1093/cercor/bhz098] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 04/09/2019] [Accepted: 04/16/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- H Kaddour
- Center for Interdisciplinary Research in Biology, Centre National de la Recherche Scientifique Unité mixte de recherche 7241/Institut national de la santé et de la recherche médicale U1050, Paris Science Lettre University, Labex MemoLife, Collège de France, 11 place Marcelin Berthelot, Paris, France
- Institut Jacques Monod, Centre National de la Recherche Scientifique Unité mixte de recherche 7592, Université Paris Diderot, Sorbonne Paris Cité, 15 Rue Hélène Brion, Paris, France
- Imagine Institute for Genetic Diseases, Université Paris Descartes, 24 Boulevard du Montparnasse, Paris, France
- Institute of Psychiatry and Neuroscience of Paris, Université Paris Descartes, 102–108 Rue de la Santé, Paris, France
| | - E Coppola
- Institut Jacques Monod, Centre National de la Recherche Scientifique Unité mixte de recherche 7592, Université Paris Diderot, Sorbonne Paris Cité, 15 Rue Hélène Brion, Paris, France
- Imagine Institute for Genetic Diseases, Université Paris Descartes, 24 Boulevard du Montparnasse, Paris, France
- Institute of Psychiatry and Neuroscience of Paris, Université Paris Descartes, 102–108 Rue de la Santé, Paris, France
| | - A A Di Nardo
- Center for Interdisciplinary Research in Biology, Centre National de la Recherche Scientifique Unité mixte de recherche 7241/Institut national de la santé et de la recherche médicale U1050, Paris Science Lettre University, Labex MemoLife, Collège de France, 11 place Marcelin Berthelot, Paris, France
| | - C Le Poupon
- Center for Interdisciplinary Research in Biology, Centre National de la Recherche Scientifique Unité mixte de recherche 7241/Institut national de la santé et de la recherche médicale U1050, Paris Science Lettre University, Labex MemoLife, Collège de France, 11 place Marcelin Berthelot, Paris, France
| | - P Mailly
- Center for Interdisciplinary Research in Biology, Centre National de la Recherche Scientifique, Core Facility Orion, 11 Place Marcelin Berthelot, Paris, France
| | - A Wizenmann
- Department of Anatomy, Institute of Clinical Anatomy and Cell, University of Tübingen, Osterbergstrasse 3, Tübingen, Germany
| | - M Volovitch
- Center for Interdisciplinary Research in Biology, Centre National de la Recherche Scientifique Unité mixte de recherche 7241/Institut national de la santé et de la recherche médicale U1050, Paris Science Lettre University, Labex MemoLife, Collège de France, 11 place Marcelin Berthelot, Paris, France
| | - A Prochiantz
- Center for Interdisciplinary Research in Biology, Centre National de la Recherche Scientifique Unité mixte de recherche 7241/Institut national de la santé et de la recherche médicale U1050, Paris Science Lettre University, Labex MemoLife, Collège de France, 11 place Marcelin Berthelot, Paris, France
| | - A Pierani
- Institut Jacques Monod, Centre National de la Recherche Scientifique Unité mixte de recherche 7592, Université Paris Diderot, Sorbonne Paris Cité, 15 Rue Hélène Brion, Paris, France
- Imagine Institute for Genetic Diseases, Université Paris Descartes, 24 Boulevard du Montparnasse, Paris, France
- Institute of Psychiatry and Neuroscience of Paris, Université Paris Descartes, 102–108 Rue de la Santé, Paris, France
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12
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Laggner M, Pollreisz A, Schmidinger G, Schmidt-Erfurth U, Chen YT. Autophagy mediates cell cycle response by regulating nucleocytoplasmic transport of PAX6 in limbal stem cells under ultraviolet-A stress. PLoS One 2017; 12:e0180868. [PMID: 28700649 PMCID: PMC5507275 DOI: 10.1371/journal.pone.0180868] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 06/22/2017] [Indexed: 01/09/2023] Open
Abstract
Limbal stem cells (LSC) account for homeostasis and regeneration of corneal epithelium. Solar ultraviolet A (UVA) is the major source causing oxidative damage in the ocular surface. Autophagy, a lysosomal degradation mechanism, is essential for physiologic function and stress defense of stem cells. PAX6, a master transcription factor governing corneal homeostasis by regulating cell cycle and cell fate of LSC, responds to oxidative stress by nucleocytoplasmic shuttling. Impaired autophagy and deregulated PAX6 have been reported in oxidative stress-related ocular surface disorders. We hypothesize a functional role for autophagy and PAX6 in LSC’s stress response to UVA. Therefore, human LSC colonies were irradiated with a sub-lethal dose of UVA and autophagic activity and intracellular reactive oxygen species (ROS) were measured by CYTO-ID assay and CM-H2DCFDA live staining, respectively. Following UVA irradiation, the percentage of autophagic cells significantly increased in LSC colonies while intracellular ROS levels remained unaffected. siRNA-mediated knockdown (KD) of ATG7 abolished UVA-induced autophagy and led to an excessive accumulation of ROS. Upon UVA exposure, LSCs displayed nuclear-to-cytoplasmic translocation of PAX6, while ATG7KD or antioxidant pretreatment largely attenuated the intracellular trafficking event. Immunofluorescence showing downregulation of proliferative marker PCNA and induction of cell cycle regulator p21 indicates cell cycle arrest in UVA-irradiated LSC. Abolishing autophagy, adenoviral-assisted restoration of nuclear PAX6 or antioxidant pretreatment abrogated the UVA-induced cell cycle arrest. Adenoviral expression of an ectopic PAX gene, PAX7, did not affect UVA cell cycle response. Furthermore, knocking down PAX6 attenuated the cell cycle progression of irradiated ATG7KD LSC by de-repressing p21 expression. Collectively, our data suggest a crosstalk between autophagy and PAX6 in regulating cell cycle response of ocular progenitors under UVA stress. Autophagy deficiency leads to impaired intracellular trafficking of PAX6, perturbed redox balance and uncurbed cell cycle progression in UVA-stressed LSCs. The coupling of autophagic machinery and PAX6 in cell cycle regulation represents an attractive therapeutic target for hyperproliferative ocular surface disorders associated with solar radiation.
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Affiliation(s)
- Maria Laggner
- Department of Ophthalmology & Optometry, Medical University of Vienna, Vienna, Austria
| | - Andreas Pollreisz
- Department of Ophthalmology & Optometry, Medical University of Vienna, Vienna, Austria
| | - Gerald Schmidinger
- Department of Ophthalmology & Optometry, Medical University of Vienna, Vienna, Austria
| | | | - Ying-Ting Chen
- Department of Ophthalmology & Optometry, Medical University of Vienna, Vienna, Austria
- * E-mail:
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13
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Shi D, Tavhelidse T, Thumberger T, Wittbrodt J, Greb T. Bifacial stem cell niches in fish and plants. Curr Opin Genet Dev 2017; 45:28-33. [PMID: 28242480 DOI: 10.1016/j.gde.2017.02.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/01/2017] [Accepted: 02/07/2017] [Indexed: 12/20/2022]
Abstract
Embryonic development is key for determining the architecture and shape of multicellular bodies. However, most cells are produced postembryonically in, at least partly, differentiated organs. In this regard, organismal growth faces common challenges in coordinating expansion and function of body structures. Here we compare two examples for postembryonic growth processes from two different kingdoms of life to reveal common regulatory principles: lateral growth of plants and the enlargement of the fish retina. In both cases, growth is based on stem cell systems mediating radial growth by a bifacial mode of tissue production. Surprisingly, although being evolutionary distinct, we find similar patterns in regulatory circuits suggesting the existence of preferable solutions to a common developmental problem.
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Affiliation(s)
- Dongbo Shi
- Centre for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | - Tinatini Tavhelidse
- Centre for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | - Thomas Thumberger
- Centre for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | - Joachim Wittbrodt
- Centre for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany
| | - Thomas Greb
- Centre for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany.
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Abstract
Heart failure and chronic renal diseases are usually progressive and only partially amenable to therapy. These disorders can be the sequelae of hypertension or worsened by hypertension. They are associated with the tissue up-regulation of multiple peptides, many of which are capable of acting within the cell interior. This article proposes that these peptides, intracrines, can form self-sustaining regulatory loops that can spread through heart or kidney, producing progressive disease. Moreover, mineralocorticoid activation seems capable of amplifying some of these peptide networks. This view suggests an expanded explanation of the pathogenesis of progressive cardiorenal disease and suggests new approaches to treatment.
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Affiliation(s)
- Richard N Re
- Ochsner Clinic Foundation, Division of Research, 1514 Jefferson Highway, New Orleans, LA 70121, USA.
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15
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An Expanded View of Progressive Cardiorenal Disorders. Am J Med Sci 2016; 351:626-33. [DOI: 10.1016/j.amjms.2016.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 03/17/2016] [Indexed: 11/23/2022]
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16
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Bernard C, Vincent C, Testa D, Bertini E, Ribot J, Di Nardo AA, Volovitch M, Prochiantz A. A Mouse Model for Conditional Secretion of Specific Single-Chain Antibodies Provides Genetic Evidence for Regulation of Cortical Plasticity by a Non-cell Autonomous Homeoprotein Transcription Factor. PLoS Genet 2016; 12:e1006035. [PMID: 27171438 PMCID: PMC4865174 DOI: 10.1371/journal.pgen.1006035] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 04/18/2016] [Indexed: 11/19/2022] Open
Abstract
During postnatal life the cerebral cortex passes through critical periods of plasticity allowing its physiological adaptation to the environment. In the visual cortex, critical period onset and closure are influenced by the non-cell autonomous activity of the Otx2 homeoprotein transcription factor, which regulates the maturation of parvalbumin-expressing inhibitory interneurons (PV cells). In adult mice, the maintenance of a non-plastic adult state requires continuous Otx2 import by PV cells. An important source of extra-cortical Otx2 is the choroid plexus, which secretes Otx2 into the cerebrospinal fluid. Otx2 secretion and internalization requires two small peptidic domains that are part of the DNA-binding domain. Thus, mutating these “transfer” sequences also modifies cell autonomous transcription, precluding this approach to obtain a cell autonomous-only mouse. Here, we develop a mouse model with inducible secretion of an anti-Otx2 single-chain antibody to trap Otx2 in the extracellular milieu. Postnatal secretion of this single-chain antibody by PV cells delays PV maturation and reduces plasticity gene expression. Induced adult expression of this single-chain antibody in cerebrospinal fluid decreases Otx2 internalization by PV cells, strongly induces plasticity gene expression and reopens physiological plasticity. We provide the first mammalian genetic evidence for a signaling mechanism involving intercellular transfer of a homeoprotein transcription factor. Our single-chain antibody mouse model is a valid strategy for extracellular neutralization that could be applied to other homeoproteins and signaling molecules within and beyond the nervous system. Classically, cell signaling is based on the secretion of molecules that bind cell surface receptors. Lipophilic agents can do without cell-surface receptors due to their ability to diffuse through the plasma membrane, but this is normally not the case for proteins, which cannot pass the membrane barrier. However, homeoprotein transcription factors represent an exception as they are secreted and internalized by live cells owing to two peptidic domains. An important illustration of this novel signaling mechanism is provided by Otx2, a homeoprotein that travels from the choroid plexus to specific inhibitory neurons in the cerebral cortex, where it regulates physiological plasticity throughout life. Because the two transfer peptides are in the DNA-binding domain of Otx2, it is impossible to mutate them without altering both cell signaling and cell-autonomous functions. We have therefore developed a mouse in which a secreted anti-Otx2 single-chain antibody can be induced to trap extracellular Otx2 while leaving its cell autonomous function untouched. We show that neutralizing extracellular Otx2 modifies the expression of plasticity genes in the visual cortex, thus providing the first genetic demonstration for homeoprotein signaling in a mammal.
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Affiliation(s)
- Clémence Bernard
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Clémentine Vincent
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Damien Testa
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Eva Bertini
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Jérôme Ribot
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Ariel A. Di Nardo
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Michel Volovitch
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
| | - Alain Prochiantz
- Centre for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS UMR 7241/INSERM U1050, PSL Research University, Paris, France
- * E-mail:
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17
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A transducible nuclear/nucleolar protein, mLLP, regulates neuronal morphogenesis and synaptic transmission. Sci Rep 2016; 6:22892. [PMID: 26961175 PMCID: PMC4790632 DOI: 10.1038/srep22892] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 02/23/2016] [Indexed: 12/03/2022] Open
Abstract
Cell-permeable proteins are emerging as unconventional regulators of signal transduction and providing a potential for therapeutic applications. However, only a few of them are identified and studied in detail. We identify a novel cell-permeable protein, mouse LLP homolog (mLLP), and uncover its roles in regulating neural development. We found that mLLP is strongly expressed in developing nervous system and that mLLP knockdown or overexpression during maturation of cultured neurons affected the neuronal growth and synaptic transmission. Interestingly, extracellular addition of mLLP protein enhanced dendritic arborization, demonstrating the non-cell-autonomous effect of mLLP. Moreover, mLLP interacts with CCCTC-binding factor (CTCF) as well as transcriptional machineries and modulates gene expression involved in neuronal growth. Together, these results illustrate the characteristics and roles of previously unknown cell-permeable protein mLLP in modulating neural development.
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18
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Ghobadian M, Nabiuni M, Parivar K, Fathi M, Pazooki J. Toxic effects of magnesium oxide nanoparticles on early developmental and larval stages of zebrafish (Danio rerio). ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 122:260-267. [PMID: 26283286 DOI: 10.1016/j.ecoenv.2015.08.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 08/08/2015] [Accepted: 08/10/2015] [Indexed: 06/04/2023]
Abstract
Magnesium oxide nanoparticles (MgONPs) are used in medicine, manufacturing and food industries. Because of their extensive application in our daily lives, environmental exposure to these nanoparticles is inevitable. The present study examined the effects of MgONPs on zebrafish (Danio rerio) early developmental stages. The results showed that, at different concentrations, MgONPs induced cellular apoptosis and intracellular reactive oxygen species. The hatching rate and survival of embryos decreased in a dose dependent manner. The 96-h LC50 value of MgONPs on zebrafish survival was 428 mg/l and the 48-h EC50 value of MgONPs on zebrafish embryo hatching rate was 175 mg/l. Moreover different types of malformation were observed in exposed embryos. The results demonstrate the toxic effects of MgONPs on zebrafish embryos and emphasize the need for further studies.
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Affiliation(s)
- Mehdi Ghobadian
- Department of Developmental Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran.
| | - Mohammad Nabiuni
- Department of Developmental Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Kazem Parivar
- Department of Developmental Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Mojtaba Fathi
- Department of Biochemistry, Zanjan University of Medical Sciences, Zanjan, Iran
| | - Jamileh Pazooki
- Department of Biological Sciences, Shahid Beheshti University, Tehran, Iran
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19
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Taylor SM, Alvarez-Delfin K, Saade CJ, Thomas JL, Thummel R, Fadool JM, Hitchcock PF. The bHLH Transcription Factor NeuroD Governs Photoreceptor Genesis and Regeneration Through Delta-Notch Signaling. Invest Ophthalmol Vis Sci 2015; 56:7496-515. [PMID: 26580854 PMCID: PMC4654396 DOI: 10.1167/iovs.15-17616] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 10/06/2015] [Indexed: 01/08/2023] Open
Abstract
PURPOSE Photoreceptor genesis in the retina requires precise regulation of progenitor cell competence, cell cycle exit, and differentiation, although information around the mechanisms that govern these events currently is lacking. In zebrafish, the basic helix-loop-helix (bHLH) transcription factor NeuroD governs photoreceptor genesis, but the signaling pathways through which NeuroD functions are unknown. The purpose of this study was to identify these pathways, and during photoreceptor genesis, Notch signaling was investigated as the putative mediator of NeuroD function. METHODS In embryos, genetic mosaic analysis was used to determine if NeuroD functions is cell- or non-cell-autonomous. Morpholino-induced NeuroD knockdown, CRISPR/Cas9 mutation, and pharmacologic and transgenic approaches were used, followed by in situ hybridization, immunocytochemistry, and quantitative RT-PCR (qRT-PCR), to identify mechanisms through which NeuroD functions. In adults, following photoreceptor ablation and NeuroD knockdown, similar methods as above were used to identify NeuroD function during photoreceptor regeneration. RESULTS In embryos, NeuroD function is non-cell-autonomous, NeuroD knockdown increases Notch pathway gene expression, Notch inhibition rescues the NeuroD knockdown-induced deficiency in cell cycle exit but not photoreceptor maturation, and Notch activation and CRISPR/Cas9 mutation of neurod recapitulate NeuroD knockdown. In adults, NeuroD knockdown prevents cell cycle exit and photoreceptor regeneration and increases Notch pathway gene expression, and Notch inhibition rescues this phenotype. CONCLUSIONS These data demonstrate that during embryonic development, NeuroD governs photoreceptor genesis via non-cell-autonomous mechanisms and that, during photoreceptor development and regeneration, Notch signaling is a mechanistic link between NeuroD and cell cycle exit. In contrast, during embryonic development, NeuroD governs photoreceptor maturation via mechanisms that are independent of Notch signaling.
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Affiliation(s)
- Scott M. Taylor
- Department of Ophthalmology and Visual Sciences University of Michigan, W. K. Kellogg Eye Center, Ann Arbor, Michigan, United States
| | - Karen Alvarez-Delfin
- Department of Biological Science, Florida State University, Tallahassee, Florida, United States
| | - Carole J. Saade
- Department of Biological Science, Florida State University, Tallahassee, Florida, United States
| | - Jennifer L. Thomas
- Departments of Anatomy/Cell Biology and Ophthalmology, Wayne State University, Detroit, Michigan, United States
| | - Ryan Thummel
- Departments of Anatomy/Cell Biology and Ophthalmology, Wayne State University, Detroit, Michigan, United States
| | - James M. Fadool
- Department of Biological Science, Florida State University, Tallahassee, Florida, United States
| | - Peter F. Hitchcock
- Department of Ophthalmology and Visual Sciences University of Michigan, W. K. Kellogg Eye Center, Ann Arbor, Michigan, United States
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20
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Dissecting the role of Engrailed in adult dopaminergic neurons--Insights into Parkinson disease pathogenesis. FEBS Lett 2015; 589:3786-94. [PMID: 26459030 DOI: 10.1016/j.febslet.2015.10.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Revised: 09/18/2015] [Accepted: 10/06/2015] [Indexed: 11/23/2022]
Abstract
The homeoprotein Engrailed (Engrailed-1/Engrailed-2, collectively En1/2) is not only a survival factor for mesencephalic dopaminergic (mDA) neurons during development, but continues to exert neuroprotective and physiological functions in adult mDA neurons. Loss of one En1 allele in the mouse leads to progressive demise of mDA neurons in the ventral midbrain starting from 6 weeks of age. These mice also develop Parkinson disease-like motor and non-motor symptoms. The characterization of En1 heterozygous mice have revealed striking parallels to central mechanisms of Parkinson disease pathogenesis, mainly related to mitochondrial dysfunction and retrograde degeneration. Thanks to the ability of homeoproteins to transduce cells, En1/2 proteins have also been used to protect mDA neurons in various experimental models of Parkinson disease. This neuroprotection is partly linked to the ability of En1/2 to regulate the translation of certain nuclear-encoded mitochondrial mRNAs for complex I subunits. Other transcription factors that govern mDA neuron development (e.g. Foxa1/2, Lmx1a/b, Nurr1, Otx2, Pitx3) also continue to function for the survival and maintenance of mDA neurons in the adult and act through partially overlapping but also diverse mechanisms.
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21
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Abstract
Signaling classically involves the secretion of diverse molecules that bind specific cell-surface receptors and engage intracellular transduction cascades. Some exceptions-namely, lipophilic agents-can cross plasma membranes to bind intracellular receptors and be carried to the nucleus to regulate transcription. Homeoprotein transcription factors are among the few proteins with such a capacity. Here, we review the signaling activities of homeoproteins in the developing and adult nervous system, with particular emphasis on axon/cell migration and postnatal critical periods of cerebral cortex plasticity. We also describe homeoprotein non-cell-autonomous mechanisms and explore how this "novel" signaling pathway impacts emerging research in brain development and physiology. In this context, we explore hypotheses on the evolution of signaling, the role of homeoproteins as early morphogens, and their therapeutic potential for neurological and psychiatric diseases.
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22
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Prochiantz A, Fuchs J, Di Nardo AA. Postnatal signalling with homeoprotein transcription factors. Philos Trans R Soc Lond B Biol Sci 2015; 369:rstb.2013.0518. [PMID: 25135979 DOI: 10.1098/rstb.2013.0518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Homeoprotein (HP) transcription factors were originally identified for their embryonic cell-autonomous developmental functions. In this review, we discuss their postnatal and adult physiological functions based on the study of Otx2, Engrailed-1 and Engrailed-2 (collectively Engrailed). For Engrailed, we discuss its function in the cell-autonomous regulation of ventral midbrain dopaminergic neuron survival and physiology and in the non-cell-autonomous maintenance of axons. For Otx2, we describe how the protein is expressed in the choroid plexus and transported into cortical parvalbumin cells where it regulates plasticity in the visual cortex. These two examples illustrate how the understanding of HP postnatal and adult functions, including signalling functions, may lead to the identification of disease-associated genetic pathways and to the development of original therapeutic strategies.
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Affiliation(s)
- Alain Prochiantz
- CIRB, CNRS UMR 7241/INSERM U1050, College de France, 11 place Marcelin Berthelot, Paris Cedex 05 75231, France
| | - Julia Fuchs
- CIRB, CNRS UMR 7241/INSERM U1050, College de France, 11 place Marcelin Berthelot, Paris Cedex 05 75231, France
| | - Ariel A Di Nardo
- CIRB, CNRS UMR 7241/INSERM U1050, College de France, 11 place Marcelin Berthelot, Paris Cedex 05 75231, France
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23
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Rampon C, Gauron C, Lin T, Meda F, Dupont E, Cosson A, Ipendey E, Frerot A, Aujard I, Le Saux T, Bensimon D, Jullien L, Volovitch M, Vriz S, Joliot A. Control of brain patterning by Engrailed paracrine transfer: a new function of the Pbx interaction domain. Development 2015; 142:1840-9. [PMID: 25926358 PMCID: PMC4440920 DOI: 10.1242/dev.114181] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 03/02/2015] [Indexed: 12/28/2022]
Abstract
Homeoproteins of the Engrailed family are involved in the patterning of mesencephalic boundaries through a mechanism classically ascribed to their transcriptional functions. In light of recent reports on the paracrine activity of homeoproteins, including Engrailed, we asked whether Engrailed intercellular transfer was also involved in brain patterning and boundary formation. Using time-controlled activation of Engrailed combined with tools that block its transfer, we show that the positioning of the diencephalic-mesencephalic boundary (DMB) requires Engrailed paracrine activity. Both zebrafish Eng2a and Eng2b are competent for intercellular transfer in vivo, but only extracellular endogenous Eng2b, and not Eng2a, participates in DMB positioning. In addition, disruption of the Pbx-interacting motif in Engrailed, known to strongly reduce the gain-of-function phenotype, also downregulates Engrailed transfer, thus revealing an unsuspected participation of the Pbx interaction domain in this pathway.
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Affiliation(s)
- Christine Rampon
- Université Paris Diderot, Sorbonne Paris Cité, Paris 75205, Cedex 13, France Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Carole Gauron
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Thibault Lin
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Francesca Meda
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France École Normale Supérieure, Institute of Biology at the Ecole Normale Supérieure (IBENS), CNRS UMR8197, INSERM U1024, PSL Research University, Paris F-75005, France
| | - Edmond Dupont
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Adrien Cosson
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Eliane Ipendey
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France École Normale Supérieure, Institute of Biology at the Ecole Normale Supérieure (IBENS), CNRS UMR8197, INSERM U1024, PSL Research University, Paris F-75005, France
| | - Alice Frerot
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Isabelle Aujard
- Ecole Normale Supérieure-PSL Research University, Département de Chimie, UMR 8640 CNRS-ENS-UPMC PASTEUR, 24, rue Lhomond, Paris 75005, France
| | - Thomas Le Saux
- Ecole Normale Supérieure-PSL Research University, Département de Chimie, UMR 8640 CNRS-ENS-UPMC PASTEUR, 24, rue Lhomond, Paris 75005, France
| | - David Bensimon
- École Normale Supérieure, Institute of Biology at the Ecole Normale Supérieure (IBENS), CNRS UMR8197, INSERM U1024, PSL Research University, Paris F-75005, France Laboratoire de Physique Statistique, UMR CNRS-ENS 8550, Paris F-75005, France Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA 90095-1569, USA
| | - Ludovic Jullien
- Ecole Normale Supérieure-PSL Research University, Département de Chimie, UMR 8640 CNRS-ENS-UPMC PASTEUR, 24, rue Lhomond, Paris 75005, France
| | - Michel Volovitch
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France École Normale Supérieure, Institute of Biology at the Ecole Normale Supérieure (IBENS), CNRS UMR8197, INSERM U1024, PSL Research University, Paris F-75005, France
| | - Sophie Vriz
- Université Paris Diderot, Sorbonne Paris Cité, Paris 75205, Cedex 13, France Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
| | - Alain Joliot
- Center for Interdisciplinary Research in Biology (CIRB) - CNRS UMR 7241, INSERM U1050, Labex MemoLife, PSL Research University, Collège de France, Paris F-75005, France
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Engrailed 1 mediates correct formation of limb innervation through two distinct mechanisms. PLoS One 2015; 10:e0118505. [PMID: 25710467 PMCID: PMC4340014 DOI: 10.1371/journal.pone.0118505] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/19/2015] [Indexed: 12/24/2022] Open
Abstract
Engrailed-1 (En1) is expressed in the ventral ectoderm of the developing limb where it plays an instructive role in the dorsal-ventral patterning of the forelimb. Besides its well-described role as a transcription factor in regulating gene expression through its DNA-binding domain, En1 may also be secreted to form an extracellular gradient, and directly impact on the formation of the retinotectal map. We show here that absence of En1 causes mispatterning of the forelimb and thus defects in the dorsal-ventral pathfinding choice of motor axons in vivo. In addition, En1 but not En2 also has a direct and specific repulsive effect on motor axons of the lateral aspect of the lateral motor column (LMC) but not on medial LMC projections. Moreover, an ectopic dorsal source of En1 pushes lateral LMC axons to the ventral limb in vivo. Thus, En1 controls the establishment of limb innervation through two distinct molecular mechanisms.
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25
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Engrailed homeoproteins in visual system development. Cell Mol Life Sci 2014; 72:1433-45. [PMID: 25432704 PMCID: PMC4366559 DOI: 10.1007/s00018-014-1776-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 10/31/2014] [Accepted: 11/06/2014] [Indexed: 12/28/2022]
Abstract
Engrailed is a homeoprotein transcription factor. This family of transcription factors is characterized by their DNA-binding homeodomain and some members, including Engrailed, can transfer between cells and regulate protein translation in addition to gene transcription. Engrailed is intimately involved in the development of the vertebrate visual system. Early expression of Engrailed in dorsal mesencephalon contributes to the development and organization of a visual structure, the optic tectum/superior colliculus. This structure is an important target for retinal ganglion cell axons that carry visual information from the retina. Engrailed regulates the expression of Ephrin axon guidance cues in the tectum/superior colliculus. More recently it has been reported that Engrailed itself acts as an axon guidance cue in synergy with the Ephrin system and is proposed to enhance retinal topographic precision.
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26
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A possible mechanism for the progression of chronic renal disease and congestive heart failure. ACTA ACUST UNITED AC 2014; 9:54-63. [PMID: 25539896 DOI: 10.1016/j.jash.2014.09.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 09/11/2014] [Accepted: 09/13/2014] [Indexed: 12/15/2022]
Abstract
Chronic neurologic diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis, as well as various forms of chronic renal disease and systolic congestive heart failure, are among the most common progressive degenerative disorders encountered in medicine. Each disease follows a nearly relentless course, albeit at varying rates, driven by progressive cell dysfunction and drop-out. The neurologic diseases are characterized by the progressive spread of disease-causing proteins (prion-like proteins) from cell to cell. Recent evidence indicates that cell autonomous renin angiotensin systems operate in heart and kidney, and it is known that functional intracrine proteins can also spread between cells. This then suggests that certain progressive degenerative cardiovascular disorders such as forms of chronic renal insufficiency and systolic congestive heart failure result from dysfunctional renin angiotensin system intracrine action spreading in kidney or myocardium.
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27
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Kim N, Acampora D, Dingli F, Loew D, Simeone A, Prochiantz A, Di Nardo AA. Immunoprecipitation and mass spectrometry identify non-cell autonomous Otx2 homeoprotein in the granular and supragranular layers of mouse visual cortex. F1000Res 2014; 3:178. [PMID: 25165539 PMCID: PMC4133762 DOI: 10.12688/f1000research.4869.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/29/2014] [Indexed: 11/20/2022] Open
Abstract
Plasticity in the visual cerebral cortex is regulated by the internalization of Otx2 homeoprotein into parvalbumin neurons in cortical layers II/III and IV. However the Otx2 locus is not active in these neurons and the protein is imported from external sources, including the choroid plexus. Because Otx1 and Otx2 may have redundant functions, we wanted to verify if part of the staining in parvalbumin neurons corresponds to Otx1 transported from cortical layer V neurons. It is demonstrated here that Otx staining in layer IV cells is maintained in Otx1-null mice. The immunoprecipitation of extracts from finely dissected granular and supragranular cortex (layers I-IV) gave immunoblots with a band corresponding to Otx2 and not Otx1. Moreover, high-resolution mass spectrometry analysis after immunoprecipitation identifies two peptides within the Otx2 homeodomain. One of these peptides is specific for Otx2 and is not found in Otx1. These results unambiguously establish that the staining in parvalbumin neurons revealed with the anti-Otx2 antibodies used in our previous studies identifies non-cell autonomous Otx2.
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Affiliation(s)
- Namsuk Kim
- CIRB, CNRS UMR 7241 / INSERM U1050, College de France, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Dario Acampora
- Institute of Genetics and Biophysics, Via Pietro Castellino 111, 80131 Napoli, Italy ; IRCCS Neuromed, 86077 Pozzilli (IS), Italy
| | - Florent Dingli
- Institut Curie, Centre de Recherche, Laboratoire de Spectrométrie de Masse Protéomique, 75248 Paris Cedex 05, France
| | - Damarys Loew
- Institut Curie, Centre de Recherche, Laboratoire de Spectrométrie de Masse Protéomique, 75248 Paris Cedex 05, France
| | - Antonio Simeone
- Institute of Genetics and Biophysics, Via Pietro Castellino 111, 80131 Napoli, Italy ; IRCCS Neuromed, 86077 Pozzilli (IS), Italy
| | - Alain Prochiantz
- CIRB, CNRS UMR 7241 / INSERM U1050, College de France, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
| | - Ariel A Di Nardo
- CIRB, CNRS UMR 7241 / INSERM U1050, College de France, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
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28
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Prochiantz A. Signaling with homeoprotein transcription factors in development and throughout adulthood. Curr Genomics 2014; 14:361-70. [PMID: 24396269 PMCID: PMC3861887 DOI: 10.2174/1389202911314060009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 06/15/2013] [Accepted: 07/15/2013] [Indexed: 11/22/2022] Open
Abstract
The concept of homeoprotein transduction as a novel signaling pathway has dramatically evolved since it was first proposed in 1991. It is now well established in several biological systems from plants to mammals. In this review, the different steps that have led to this unexpected observation are recalled and the developmental and physiological models that have allowed us (and a few others) to consolidate the original hypothesis are described. Because homeoprotein signaling is active in plants and animals it is proposed that it has predated the separation between animals and plants and is thus very ancient. This may explain why the basic phenomenon of homeoprotein transduction is so minimalist, requiring no specific receptors or transduction pathways beside those offered by mitochondria, organelles present in all eukaryotic cells. Indeed complexity has been added in the course of evolution and the conservation of homeoprotein transduction is discussed in the context of its synergy with bona fide signaling mechanism that may have added robustness to this primitive cell communication device. The same synergy possibly explains why homeoprotein signaling is important both in embryonic development and in adult functions fulfilled by signaling entities (e.g. growth factors) themselves active throughout development and in the adult. The cell biological mechanism of homeoprotein transfer is also discussed. Although it is clear that many questions are still in want of precise answers, it appears that the sequences responsible both for secretion and internalization are in the DNA-binding domain and very highly conserved among most homeoproteins. On this basis, it is proposed that this signaling pathway is likely to imply as many as 200 proteins that participate in a myriad of developmental and physiological pathways.
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Affiliation(s)
- A Prochiantz
- College de France, Centre for Interdisciplinary Research in Biology (CIRB), UMR CNRS 7241/INSERM 1050, Labex Memolife, PSL Research University, Development and Neuropharmacology group, 11 place Marcelin Berthelot, 75231 Paris Cedex 05, France
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Abnormal neuronal differentiation and mitochondrial dysfunction in hair follicle-derived induced pluripotent stem cells of schizophrenia patients. Mol Psychiatry 2013; 18:1067-76. [PMID: 23732879 DOI: 10.1038/mp.2013.67] [Citation(s) in RCA: 182] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 02/19/2013] [Accepted: 04/08/2013] [Indexed: 02/08/2023]
Abstract
One of the prevailing hypotheses suggests schizophrenia as a neurodevelopmental disorder, involving dysfunction of dopaminergic and glutamatergic systems. Accumulating evidence suggests mitochondria as an additional pathological factor in schizophrenia. An attractive model to study processes related to neurodevelopment in schizophrenia is reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) and differentiating them into different neuronal lineages. iPSCs from three schizophrenia patients and from two controls were reprogrammed from hair follicle keratinocytes, because of their accessibility and common ectodermal origin with neurons. iPSCs were differentiated into Pax6(+)/Nestin(+) neural precursors and then further differentiated into β3-Tubulin(+)/tyrosine hydroxylase(+)/DAT(+) dopaminergic neurons. In addition, iPSCs were differentiated through embryonic bodies into β3-Tubulin(+)/Tbox brain1(+) glutamatergic neurons. Schizophrenia-derived dopaminergic cells showed severely impaired ability to differentiate, whereas glutamatergic cells were unable to maturate. Mitochondrial respiration and its sensitivity to dopamine-induced inhibition were impaired in schizophrenia-derived keratinocytes and iPSCs. Moreover, we observed dissipation of mitochondrial membrane potential (Δψm) and perturbations in mitochondrial network structure and connectivity in dopaminergic along the differentiation process and in glutamatergic cells. Our data unravel perturbations in neural differentiation and mitochondrial function, which may be interconnected, and of relevance to dysfunctional neurodevelopmental processes in schizophrenia.
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Kayam G, Kohl A, Magen Z, Peretz Y, Weisinger K, Bar A, Novikov O, Brodski C, Sela-Donenfeld D. A novel role for Pax6 in the segmental organization of the hindbrain. Development 2013; 140:2190-202. [PMID: 23578930 DOI: 10.1242/dev.089136] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Complex patterns and networks of genes coordinate rhombomeric identities, hindbrain segmentation and neuronal differentiation and are responsible for later brainstem functions. Pax6 is a highly conserved transcription factor crucial for neuronal development, yet little is known regarding its early roles during hindbrain segmentation. We show that Pax6 expression is highly dynamic in rhombomeres, suggesting an early function in the hindbrain. Utilization of multiple gain- and loss-of-function approaches in chick and mice revealed that loss of Pax6 disrupts the sharp expression borders of Krox20, Kreisler, Hoxa2, Hoxb1 and EphA and leads to their expansion into adjacent territories, whereas excess Pax6 reduces these expression domains. A mutual negative cross-talk between Pax6 and Krox20 allows these genes to be co-expressed in the hindbrain through regulation of the Krox20-repressor gene Nab1 by Pax6. Rhombomere boundaries are also distorted upon Pax6 manipulations, suggesting a mechanism by which Pax6 acts to set hindbrain segmentation. Finally, FGF signaling acts upstream of the Pax6-Krox20 network to regulate Pax6 segmental expression. This study unravels a novel role for Pax6 in the segmental organization of the early hindbrain and provides new evidence for its significance in regional organization along the central nervous system.
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Affiliation(s)
- Galya Kayam
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, 76100 Rehovot, Israel
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31
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Spatazza J, Di Lullo E, Joliot A, Dupont E, Moya KL, Prochiantz A. Homeoprotein signaling in development, health, and disease: a shaking of dogmas offers challenges and promises from bench to bed. Pharmacol Rev 2013; 65:90-104. [PMID: 23300132 DOI: 10.1124/pr.112.006577] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Homeoproteins constitute a major class of transcription factors active throughout development and in adulthood. Their membrane transduction properties were discovered over 20 years ago, opening an original field of research in the domain of vector peptides and signal transduction. In early development, homeoprotein transfer participates in tissue patterning, cell/axon guidance, and migration. In the axon guidance model, homeoproteins exert their non-cell autonomous activity through the regulation of translation, in particular, that of nuclear-transcribed mitochondrial mRNAs. An important aspect of these studies on patterning and migration is that homeoproteins sensitize the cells to the action of other growth factors, thus cooperating with established signaling pathways. The role of homeoprotein signaling at later developmental stages is also of interest. In particular, the transfer of homeoprotein Otx2 into parvalbumin-expressing inhibitory neurons (PV-cells) in the visual cortex regulates cortical plasticity. The molecular deciphering of the interaction of Otx2 with binding sites at the surface of PV-cells has allowed the development of a specific Otx2 antagonist that reopens plasticity in the adult cortex and cures mice from experimental amblyopia, a neurodevelopmental disease. Finally, the use of homeoproteins as therapeutic proteins in mouse models of glaucoma and Parkinson disease is reviewed. In the latter case, engrailed homeoproteins protect mesencephalic dopaminergic neurons by increasing the local translation of complex I mitochondrial mRNAs. In conclusion, this review synthesizes 20 years of work on the fundamental and potentially translational aspects of homeoprotein signaling.
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Affiliation(s)
- Julien Spatazza
- Development and Neuropharmacology Group, College de France, Centre for Interdisciplinary Research in Biology, CNRS UMR 7241/INSERM U1050, Labex Memolife, PSL Research University, Paris, France
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32
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New insights into the mechanism of lens development using zebra fish. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 296:1-61. [PMID: 22559937 DOI: 10.1016/b978-0-12-394307-1.00001-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
On the basis of recent advances in molecular biology, genetics, and live-embryo imaging, direct comparisons between zebra fish and human lens development are being made. The zebra fish has numerous experimental advantages for investigation of fundamental biomedical problems that are often best studied in the lens. The physical characteristics of visible light can account for the highly coordinated cell differentiation during formation of a beautifully transparent, refractile, symmetric optical element, the biological lens. The accessibility of the zebra fish lens for direct investigation during rapid development will result in new knowledge about basic functional mechanisms of epithelia-mesenchymal transitions, cell fate, cell-matrix interactions, cytoskeletal interactions, cytoplasmic crowding, membrane transport, cell adhesion, cell signaling, and metabolic specialization. The lens is well known as a model for characterization of cell and molecular aging. We review the recent advances in understanding vertebrate lens development conducted with zebra fish.
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Sousounis K, Tsonis PA. Patterns of gene expression in microarrays and expressed sequence tags from normal and cataractous lenses. Hum Genomics 2012; 6:14. [PMID: 23244575 PMCID: PMC3563465 DOI: 10.1186/1479-7364-6-14] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Accepted: 05/14/2012] [Indexed: 11/30/2022] Open
Abstract
In this contribution, we have examined the patterns of gene expression in normal and cataractous lenses as presented in five different papers using microarrays and expressed sequence tags. The purpose was to evaluate unique and common patterns of gene expression during development, aging and cataracts.
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Affiliation(s)
- Konstantinos Sousounis
- Department of Biology and Center for Tissue Regeneration and Engineering, University of Dayton, Dayton, OH 45469-2320, USA
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Stettler O, Joshi RL, Wizenmann A, Reingruber J, Holcman D, Bouillot C, Castagner F, Prochiantz A, Moya KL. Engrailed homeoprotein recruits the adenosine A1 receptor to potentiate ephrin A5 function in retinal growth cones. Development 2012; 139:215-24. [PMID: 22147955 DOI: 10.1242/dev.063875] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Engrailed 1 and engrailed 2 homeoprotein transcription factors (collectively Engrailed) display graded expression in the chick optic tectum where they participate in retino-tectal patterning. In vitro, extracellular Engrailed guides retinal ganglion cell (RGC) axons and synergises with ephrin A5 to provoke the collapse of temporal growth cones. In vivo disruption of endogenous extracellular Engrailed leads to misrouting of RGC axons. Here we characterise the signalling pathway of extracellular Engrailed. Our results show that Engrailed/ephrin A5 synergy in growth cone collapse involves adenosine A1 receptor activation after Engrailed-dependent ATP synthesis, followed by ATP secretion and hydrolysis to adenosine. This is, to our knowledge, the first evidence for a role of the adenosine A1 receptor in axon guidance. Based on these results, together with higher expression of the adenosine A1 receptor in temporal than nasal growth cones, we propose a computational model that illustrates how the interaction between Engrailed, ephrin A5 and adenosine could increase the precision of the retinal projection map.
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Affiliation(s)
- Olivier Stettler
- CNRS Unité mixte de Recherche 7241/INSERM U1050, Equipe FRM, Center for Interdisciplinary Research in Biology, Collège de France, 11, place Marcelin Berthelot, 75005 Paris, France
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35
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Di Lullo E, Haton C, Le Poupon C, Volovitch M, Joliot A, Thomas JL, Prochiantz A. Paracrine Pax6 activity regulates oligodendrocyte precursor cell migration in the chick embryonic neural tube. Development 2011; 138:4991-5001. [PMID: 22028031 DOI: 10.1242/dev.066282] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Homeoprotein transcription factors play fundamental roles in development, ranging from embryonic polarity to cell differentiation and migration. Research in recent years has underscored the physiological importance of homeoprotein intercellular transfer in eye field development, axon guidance and retino-tectal patterning, and visual cortex plasticity. Here, we have used the embryonic chick neural tube to investigate a possible role for homeoprotein Pax6 transfer in oligodendrocyte precursor cell (OPC) migration. We report the extracellular expression of Pax6 and the effects of gain and loss of extracellular Pax6 activity on OPCs. Open book cultures with recombinant Pax6 protein or Pax6 blocking antibodies, as well as in ovo gene transfer experiments involving expression of secreted Pax6 protein or secreted Pax6 antibodies, provide converging evidences that OPC migration is promoted by extracellular Pax6. The paracrine effect of Pax6 on OPC migration is thus a new example of direct non-cell autonomous homeoprotein activity.
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Affiliation(s)
- Elizabeth Di Lullo
- Collège de France, Center for Interdisciplinary Research in Biology, 11 place Marcelin Berthelot, Paris F-75005, France
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36
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Layalle S, Volovitch M, Mugat B, Bonneaud N, Parmentier ML, Prochiantz A, Joliot A, Maschat F. Engrailed homeoprotein acts as a signaling molecule in the developing fly. Development 2011; 138:2315-23. [PMID: 21558379 DOI: 10.1242/dev.057059] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Homeodomain transcription factors classically exert their morphogenetic activities through the cell-autonomous regulation of developmental programs. In vertebrates, several homeoproteins have also been shown to have direct non-cell-autonomous activities in the developing nervous system. We present the first in vivo evidence for homeoprotein signaling in Drosophila. Focusing on wing development as a model, we first demonstrate that the homeoprotein Engrailed (En) is secreted. Using single-chain anti-En antibodies expressed under the control of a variety of promoters, we delineate the wing territories in which secreted En acts. We show that En is a short-range signaling molecule that participates in anterior crossvein development, interacting with the Dpp signaling pathway. This report thus suggests that direct signaling with homeoproteins is an evolutionarily conserved phenomenon that is not restricted to neural tissues and involves interactions with bona fide signal transduction pathways.
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Affiliation(s)
- Sophie Layalle
- Institut de Génétique Humaine, CNRS, UPR 1142, 141 rue de la Cardonille, 34396 Montpellier, France
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Joshi RL, Torero Ibad R, Rheey J, Castagner F, Prochiantz A, Moya KL. Cell non-autonomous functions of homeoproteins in neuroprotection in the brain. FEBS Lett 2011; 585:1573-8. [PMID: 21565195 DOI: 10.1016/j.febslet.2011.05.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 04/29/2011] [Accepted: 05/01/2011] [Indexed: 12/19/2022]
Abstract
Homeoproteins transcription factors can transfer between cells and play important roles in development. However, some of these homeoproteins are expressed in the adult, but their function is unknown. The loss of mesencephalic dopaminergic (mDA) neurons is the cause of Parkinson's disease. In mice lacking a functional allele for the Engrailed 1 homeoprotein, mDA neurons progressively die starting about 6 weeks after birth. Infusion of recombinant Engrailed stops the death of these neurons demonstrating that homeoproteins can be neuroprotective. This has been extended to retinal ganglion cell neurons (RGCs), which die in glaucoma and optic neuropathies. The homeoprotein Otx2 promotes the survival of injured adult RGCs both in vitro and in vivo. These examples raise the possibility that homeoproteins may provide neuroprotection to neurons vulnerable in other neurodegenerative diseases.
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Affiliation(s)
- Rajiv L Joshi
- Development and Neuropharmacology Group, Centre for Interdisciplinary Research in Biology (CIRB), CNRS UMR 7241, INSERM U 1050, Collège de France, Paris, France.
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Prochiantz A. Homeoprotein intercellular transfer, the hidden face of cell-penetrating peptides. Methods Mol Biol 2011; 683:249-57. [PMID: 21053135 DOI: 10.1007/978-1-60761-919-2_18] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Cell-Penetrating Peptides (CPPs) are small peptides internalized by live cells, gaining access to their cytoplasm and intracellular organelles (i.e., mitochondria, nucleus) and are used as pharmacological tools. This is indeed a very important issue, fully justifying the efforts of several groups to better understand the mechanisms of peptide transduction and to verify if and how this strategy can be translated into therapeutic improvements. However, the discovery of peptide transduction is a consequence of that of a novel signaling mechanism based on the intercellular transfer of homeoprotein transcription factors. Indeed, the first and probably most popular CPPs (Tat and Penetratin) correspond to domains that drive TAT (HIV) and homeoprotein transcription factors into the cells. These findings have fostered several studies on transduction and allowed the design of "nonnatural" CPPs. As useful as they are, these lines of research have, in general, neglected the fact that protein transduction is a signaling mechanism, in its own right, with important physiological functions. In this chapter, I describe some of these functions and propose that this class of signaling molecules, in particular homeoproteins, may also be used as therapeutic agents.
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Johansson HJ, Andaloussi SEL, Langel U. Mimicry of protein function with cell-penetrating peptides. Methods Mol Biol 2011; 683:233-247. [PMID: 21053134 DOI: 10.1007/978-1-60761-919-2_17] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Proteins are essential components of cellular processes inside cells, and their interactions between each other and with genes are important for the normal physiological functioning of cells as well as for disease states. Modulating protein interactions by different means can potentially control these interactions and restore normal function to diseased cells. The ways to do so are multiple, and such efforts often begin with knowledge of potential target proteins in order to devise mediators that retain the function of the original protein, i.e., mimic the protein functions. An alternative strategy is to utilize protein mimics to inhibit target proteins rather than restoring the activity of a protein. The vast majority of protein -mimics exploited to date have been designed to inhibit the activity of oncogenes or activate tumor suppressors for the purpose of tumor therapy. These protein mimics are usually based on small organic compounds or peptides, derived from interaction surfaces of the proteins, and in some cases, full proteins have been exploited. Although peptides and proteins are naturally highly specific and efficient inside cells, they suffer from low bioavailability resulting from their inability to enter cells. One strategy increasingly employed to facilitate the internalization of peptides and proteins has been to chemically conjugate them to cell-penetrating peptides (CPP) or to recombinantly express protein-CPP fusion constructs.This chapter provides an overview of some of the aspects of perturbing and mimicking protein interactions using peptides and proteins and CPP as transport vectors.
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Affiliation(s)
- Henrik J Johansson
- Department of Oncology-Pathology, Karolinska Biomics Center, Karolinska Institutet, Stockholm, Sweden.
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40
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Thomas M. Role of transcription factors in cell replacement therapies for neurodegenerative conditions. Regen Med 2010; 5:441-50. [PMID: 20455654 DOI: 10.2217/rme.10.17] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Parkinson's disease is the second most common neurological condition, behind dementia, for which there is currently no cure. A promising curative treatment approach is cell replacement therapy, which involves the introduction of new dopaminergic cells into a degenerative Parkinson's disease brain. The future progression of this field into a clinically viable treatment option is reliant on generating replacement dopaminergic cells. Furthermore, as the ability of transplanted dopaminergic neurons to form connections with host tissue is dependent on where the cells are derived from, the replacement dopaminergic cells will need to be phenotypically similar to substantia nigra dopaminergic neurons. This article focuses on how developmental transcription factors have been utilized to assist the progression of stem cell therapies for Parkinson's disease. Key transcription factor-mediated stages of substantia nigra dopaminergic neuronal development is described in the belief that a comprehensive understanding of this specific dopaminergic differentiation pathway is necessary for the progression of successful cell therapies for Parkinson's disease.
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Affiliation(s)
- Meghan Thomas
- Parkinson's Center (ParkC), Vario Health Institute, Edith Cowan University, Perth, Australia.
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41
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Winterbottom EF, Illes JC, Faas L, Isaacs HV. Conserved and novel roles for the Gsh2 transcription factor in primary neurogenesis. Development 2010; 137:2623-31. [DOI: 10.1242/dev.047159] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The Gsx genes encode members of the ParaHox family of homeodomain transcription factors, which are expressed in the developing central nervous system in members of all major groups of bilaterians. The Gsx genes in Xenopus show similar patterns of expression to their mammalian homologues during late development. However, they are also expressed from early neurula stages in an intermediate region of the open neural plate where primary interneurons form. The Gsx homologue in the protostome Drosophila is expressed in a corresponding intermediate region of the embryonic neuroectoderm, and is essential for the correct specification of the neuroblasts that arise from it, suggesting that Gsx genes may have played a role in intermediate neural specification in the last common bilaterian ancestor. Here, we show that manipulation of Gsx function disrupts the differentiation of primary interneurons. We demonstrate that, despite their similar expression patterns, the uni-directional system of interactions between homeodomain transcription factors from the Msx, Nkx and Gsx families in the Drosophila neuroectoderm is not conserved between their homologues in the Xenopus open neural plate. Finally, we report the identification of Dbx1 as a direct target of Gsh2-mediated transcriptional repression, and show that a series of cross-repressive interactions, reminiscent of those that exist in the amniote neural tube, act between Gsx, Dbx and Nkx transcription factors to pattern the medial aspect of the central nervous system at open neural plate stages in Xenopus.
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Affiliation(s)
| | - Jean C. Illes
- Area 11, Department of Biology, University of York, York YO10 5YW, UK
| | - Laura Faas
- Area 11, Department of Biology, University of York, York YO10 5YW, UK
| | - Harry V. Isaacs
- Area 11, Department of Biology, University of York, York YO10 5YW, UK
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Extracellular Engrailed participates in the topographic guidance of retinal axons in vivo. Neuron 2009; 64:355-366. [PMID: 19914184 DOI: 10.1016/j.neuron.2009.09.018] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2009] [Indexed: 12/21/2022]
Abstract
Engrailed transcription factors regulate the expression of guidance cues that pattern retinal axon terminals in the dorsal midbrain. They also act directly to guide axon growth in vitro. We show here that an extracellular En gradient exists in the tectum along the anterior-posterior axis. Neutralizing extracellular Engrailed in vivo with antibodies expressed in the tectum causes temporal axons to map aberrantly to the posterior tectum in chick and Xenopus. Furthermore, posterior membranes from wild-type tecta incubated with anti-Engrailed antibodies or posterior membranes from Engrailed-1 knockout mice exhibit diminished repulsive activity for temporal axons. Since EphrinAs play a major role in anterior-posterior mapping, we tested whether Engrailed cooperates with EphrinA5 in vitro. We find that Engrailed restores full repulsion to axons given subthreshold doses of EphrinA5. Collectively, our results indicate that extracellular Engrailed contributes to retinotectal mapping in vivo by modulating the sensitivity of growth cones to EphrinA.
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43
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Re RN, Cook JL. Senescence, apoptosis, and stem cell biology: the rationale for an expanded view of intracrine action. Am J Physiol Heart Circ Physiol 2009; 297:H893-901. [PMID: 19592610 PMCID: PMC2755987 DOI: 10.1152/ajpheart.00414.2009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Accepted: 07/02/2009] [Indexed: 12/28/2022]
Abstract
Some extracellular-signaling peptides also at times function within the intracellular space. We have termed these peptides intracrines and have argued that intracrine function is associated with a wide variety of peptides/proteins including hormones, growth factors, cytokines, enzymes, and DNA-binding proteins among others. Here we consider the possibility that intracrines participate in the related phenomena of senescence, apoptosis, and stem cell regulation of tissue biology. Based on this analysis, we also suggest that the concept of intracrine action be expanded to include possible regulatory peptide transfer via exosomes/microvesicles and possibly by nanotubes. Moreover, the process of microvesicular and nanotube transfer of peptides and other biologically relevant molecules, which we inclusively term laterality, is explored. These notions have potentially important therapeutic implications, including implications for the therapy of cardiovascular disease.
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Affiliation(s)
- Richard N Re
- Ochsner Clinic Foundation, New Orleans, LA 70121, USA.
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44
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Molecular cloning and characterization of homologs of achaete-scute and hairy-enhancer of split in the olfactory organ of the spiny lobster Panulirus argus. J Mol Neurosci 2009; 39:294-307. [PMID: 19322682 DOI: 10.1007/s12031-009-9195-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Accepted: 03/09/2009] [Indexed: 02/06/2023]
Abstract
The olfactory organ of the Caribbean spiny lobster Panulirus argus maintains lifelong proliferation and turnover of olfactory receptor neurons (ORNs). Towards examining the molecular basis of this adult neurogenesis, we search for expression of homologs of proneural, neurogenic, and pre-pattern genes in this olfactory organ. We report here a homolog of the proneural Achaete-Scute family, called splash (spiny lobster achaete-scute homolog), and a homolog of the pre-pattern and neurogenic hairy-enhancer of split family, called splhairy (spiny lobster hairy). Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) indicates a molt stage dependence of the levels of expression of splash and splhairy mRNA in the olfactory organ, with higher expression in premolt than in postmolt or intermolt animals, which is positively correlated with rates of neurogenesis. splash and splhairy mRNA are expressed not only in the olfactory organ but also in other tissues, albeit at lower levels, irrespective of molt stage. We conclude that the expression of achaete-scute and hairy-enhancer of split in the proliferation zone of the olfactory organ of spiny lobsters and their enhanced expression in premolt animals suggest that they play a role in the proliferation of ORNs and that their expression in regions of the olfactory organ populated by mature ORNs and in other tissues suggests that they have additional functions.
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Abstract
Intracrine peptides and proteins participate in the regulation of adult and pleuripotential embryonic-like stem cells. Included among these factors are VEGF, dynorphin, the readthrough form of acetylcholinesterase, Oct3/4, Pdx-1, Pax-6, and high-mobility group protein B1, among others. In some cases, the establishment of intracrine feedback loops can be shown to be relevant to this regulation, consistent with previously proposed principles of intracrine action. Here the role of intracrines in stem cell regulation is reviewed, with particular attention to the intracrine regulation of cardiac stem cells. The reprogramming of cells to restore the pleuripotent phenotype and the possible role of stem/progenitor cells in neoplasia are also discussed.
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Affiliation(s)
- Richard N Re
- Ochsner Clinic Foundation, New Orleans, LA 70121, USA.
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46
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Lee J, Willer JR, Willer GB, Smith K, Gregg RG, Gross JM. Zebrafish blowout provides genetic evidence for Patched1-mediated negative regulation of Hedgehog signaling within the proximal optic vesicle of the vertebrate eye. Dev Biol 2008; 319:10-22. [PMID: 18479681 DOI: 10.1016/j.ydbio.2008.03.035] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 03/21/2008] [Accepted: 03/25/2008] [Indexed: 11/16/2022]
Abstract
In this study, we have characterized the ocular defects in the recessive zebrafish mutant blowout that presents with a variably penetrant coloboma phenotype. blowout mutants develop unilateral or bilateral colobomas and as a result, the retina and retinal pigmented epithelium are not contained within the optic cup. Colobomas result from defects in optic stalk morphogenesis whereby the optic stalk extends into the retina and impedes the lateral edges of the choroid fissure from meeting and fusing. The expression domain of the proximal optic vesicle marker pax2a is expanded in blowout at the expense of the distal optic vesicle marker pax6, suggesting that the initial patterning of the optic vesicle into proximal and distal territories is disrupted in blowout. Later aspects of distal optic cup formation (i.e. retina development) are normal in blowout mutants, however. Positional cloning of blowout identified a nonsense mutation in patched1, a negative regulator of the Hedgehog pathway, as the underlying cause of the blowout phenotype. Expanded domains of expression of the Hedgehog target genes patched1 and patched2 were observed in blowout, consistent with a loss of Patched1 function and upregulation of Hedgehog pathway activity. Moreover, colobomas in blowout could be suppressed by pharmacologically inhibiting the Hedgehog pathway with cyclopamine, and maximal rescue occurred when embryos were exposed to cyclopamine between 5.5 and 13 hours post-fertilization. These observations highlight the critical role that Hedgehog pathway activity plays in mediating patterning of the proximal/distal axis of the optic vesicle during the early phases of eye development and they provide genetic confirmation for the integral role that patched1-mediated negative regulation of Hedgehog signaling plays during vertebrate eye development.
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Affiliation(s)
- Jiwoon Lee
- Section of Molecular Cell and Developmental Biology and Institute for Cell and Molecular Biology, USA
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Joliot A, Prochiantz A. Homeoproteins as natural Penetratin cargoes with signaling properties. Adv Drug Deliv Rev 2008; 60:608-13. [PMID: 18037528 DOI: 10.1016/j.addr.2007.09.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Accepted: 09/28/2007] [Indexed: 10/22/2022]
Abstract
Most of this volume is dedicated to a very important and pragmatic issue which is to design ways of internalizing active pharmacological compounds into cells. In fact, many vectors have now been developed and the improvement in the technology can be seen on two main fronts. A first one is the identification of extremely efficient cargoes, for example siRNAs, which can enter the cells once attached to the vectors. A second one is the development of chemical vectors designed after the properties of the peptides and of tags allowing in vivo addressing to specific organs, for example the brain, cell types or sub-cellular compartments. This chapter is of a different nature, as it is devoted to the physiological significance of protein transduction and to the comparative analysis of the Penetratin PTD with its parental proteins, the homeoproteins. Although very academic, these two issues are of practical interest for the rational design of new vectors and the identification of unforeseen pathological mechanisms and pharmacological targets.
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Prochiantz A. Protein and peptide transduction, twenty years later a happy birthday. Adv Drug Deliv Rev 2008; 60:448-51. [PMID: 18053614 DOI: 10.1016/j.addr.2007.08.040] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Accepted: 08/31/2007] [Indexed: 11/15/2022]
Abstract
This commentary underscores the following aspects of Cell Permeable Peptides/Transduction Peptides (CPP/PTD) research. First the discovery of CPP/PTD takes its origin in the observation that some full-length transcription factors navigate between cells. The latter physiological origin is of interest as the significance of this new mode of signal transduction is not yet fully understood. A second point is that most breakthroughs in the domain have been made possible by long lasting collaborations between biologists, chemists and physicists. It is beyond doubt that the understanding of the mechanisms of secretion and internalization, in parallel with the development of new transduction compounds, not only peptides, will require that such collaborative efforts be amplified. Finally, although the domain is flourishing and our minds full of hope, it must be said that many points need to be resolved before getting close to bedside. Among these points are bio-disponibility, toxicity and specific addressing to body regions, cell types and intracellular compartments. In brief, beyond this happy birthday, there is still plenty of home work!
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Affiliation(s)
- Alain Prochiantz
- Development and Neuropharmacology, UMR CNRS 8542, Ecole normale supérieure, 46 rue d'Ulm, 75230 Paris Cedex 05, France.
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Burket CT, Montgomery JE, Thummel R, Kassen SC, LaFave MC, Langenau DM, Zon LI, Hyde DR. Generation and characterization of transgenic zebrafish lines using different ubiquitous promoters. Transgenic Res 2007; 17:265-79. [PMID: 17968670 DOI: 10.1007/s11248-007-9152-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Accepted: 10/09/2007] [Indexed: 01/24/2023]
Abstract
Two commonly used promoters to ubiquitously express transgenes in zebrafish are the Xenopus laevis elongation factor 1 alpha promoter (XlEef1a1) and the zebrafish histone variant H2A.F/Z (h2afv) promoter. Recently, transgenes utilizing these promoters were shown to be silenced in certain adult tissues, particularly the central nervous system. To overcome this limitation, we cloned the promoters of four zebrafish genes that likely are transcribed ubiquitously throughout development and into the adult. These four genes are the TATA box binding protein gene, the taube nuss-like gene, the eukaryotic elongation factor 1-gamma gene, and the beta-actin-1 gene. We PCR amplified approximately 2.5 kb upstream of the putative translational start site of each gene and cloned each into a Tol2 expression vector that contains the EGFP reporter transgene. We used these four Tol2 vectors to independently generate stable transgenic fish lines for analysis of transgene expression during development and in the adult. We demonstrated that all four promoters drive a very broad pattern of EGFP expression throughout development and the adult. Using the retina as a well-characterized component of the CNS, all four promoters appeared to drive EGFP expression in all neuronal and non-neuronal cells of the adult retina. In contrast, the h2afv promoter failed to express EGFP in the adult retina. When we examined EGFP expression in the various cells of the blood cell lineage, we observed that all four promoters exhibited a more heterogenous expression pattern than either the XlEef1a1 or h2afv promoters. While these four ubiquitous promoters did not express EGFP in all the adult blood cells, they did express EGFP throughout the CNS and in broader expression patterns in the adult than either the XlEef1a1 or h2afv promoters. For these reasons, these four promoters will be valuable tools for expressing transgenes in adult zebrafish.
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Affiliation(s)
- Christopher T Burket
- Department of Biological Sciences and the Center for Zebrafish Research, University of Notre Dame, Notre Dame, IN 46556, USA
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Brunet I, Di Nardo AA, Sonnier L, Beurdeley M, Prochiantz A. The topological role of homeoproteins in the developing central nervous system. Trends Neurosci 2007; 30:260-7. [PMID: 17418905 DOI: 10.1016/j.tins.2007.03.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Revised: 02/13/2007] [Accepted: 03/29/2007] [Indexed: 11/24/2022]
Abstract
Homeogenes encode homeoprotein transcription factors that have fundamental roles in development. They are key players in genetic networks that lay out the body plan and also determine morphology and physiology at the cellular and multicellular level. However, homeoproteins share activities that extend beyond transcription, including translation regulation and signalling. For example, homeoproteins participate in the definition of territories in the neuroepithelium and also have a function in axonal guidance. Based on these examples, we propose that homeoproteins are not only morphogenetic transcription factors, but also morphogens themselves.
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Affiliation(s)
- Isabelle Brunet
- Unité Mixte de Recherche 8542, Development and Evolution of the Nervous System (Development and Neuropharmacology Group), Ecole normale supérieure, 46 rue d'Ulm, 75005 Paris, France
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