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Sena E, Feistel K, Durand BC. An Evolutionarily Conserved Network Mediates Development of the zona limitans intrathalamica, a Sonic Hedgehog-Secreting Caudal Forebrain Signaling Center. J Dev Biol 2016; 4:jdb4040031. [PMID: 29615594 PMCID: PMC5831802 DOI: 10.3390/jdb4040031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 09/29/2016] [Accepted: 10/13/2016] [Indexed: 12/16/2022] Open
Abstract
Recent studies revealed new insights into the development of a unique caudal forebrain-signaling center: the zona limitans intrathalamica (zli). The zli is the last brain signaling center to form and the first forebrain compartment to be established. It is the only part of the dorsal neural tube expressing the morphogen Sonic Hedgehog (Shh) whose activity participates in the survival, growth and patterning of neuronal progenitor subpopulations within the thalamic complex. Here, we review the gene regulatory network of transcription factors and cis-regulatory elements that underlies formation of a shh-expressing delimitated domain in the anterior brain. We discuss evidence that this network predates the origin of chordates. We highlight the contribution of Shh, Wnt and Notch signaling to zli development and discuss implications for the fact that the morphogen Shh relies on primary cilia for signal transduction. The network that underlies zli development also contributes to thalamus induction, and to its patterning once the zli has been set up. We present an overview of the brain malformations possibly associated with developmental defects in this gene regulatory network (GRN).
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Affiliation(s)
- Elena Sena
- Institut Curie, Université Paris Sud, INSERM U1021, CNRS UMR3347, Centre Universitaire, Bâtiment 110, F-91405 Orsay Cedex, France.
| | - Kerstin Feistel
- Institute of Zoology, University of Hohenheim, Garbenstr. 30, 70593 Stuttgart, Germany.
| | - Béatrice C Durand
- Institut Curie, Université Paris Sud, INSERM U1021, CNRS UMR3347, Centre Universitaire, Bâtiment 110, F-91405 Orsay Cedex, France.
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52
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Pedersen LB, Mogensen JB, Christensen ST. Endocytic Control of Cellular Signaling at the Primary Cilium. Trends Biochem Sci 2016; 41:784-797. [DOI: 10.1016/j.tibs.2016.06.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 06/03/2016] [Accepted: 06/07/2016] [Indexed: 01/20/2023]
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53
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Matías-Guíu J, Oreja-Guevara C, Matias-Guiu JA, Gomez-Pinedo U. Vitamin D and remyelination in multiple sclerosis. Neurologia 2016; 33:177-186. [PMID: 27321170 DOI: 10.1016/j.nrl.2016.05.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Accepted: 05/12/2016] [Indexed: 12/01/2022] Open
Abstract
INTRODUCTION Several studies have found an association between multiple sclerosis and vitamin D (VD) deficiency, which suggests that VD may play a role in the immune response. However, few studies have addressed its role in remyelination. DEVELOPMENT The VD receptor and the enzymes transforming VD into metabolites which activate the VD receptor are expressed in central nervous system (CNS) cells, which suggests a potential effect of VD on the CNS. Both in vitro and animal model studies have shown that VD may play a role in myelination by acting on factors that influence the microenvironment which promotes both proliferation and differentiation of neural stem cells into oligodendrocyte progenitor cells and oligodendrocytes. It remains unknown whether the mechanisms of internalisation of VD in the CNS are synergistic with or antagonistic to the mechanisms that facilitate the entry of VD metabolites into immune cells. CONCLUSIONS VD seems to play a role in the CNS and our hypothesis is that VD is involved in remyelination. Understanding the basic mechanisms of VD in myelination is necessary to manage multiple sclerosis patients with VD deficiency.
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Affiliation(s)
- J Matías-Guíu
- Servicio de Neurología, Hospital Clínico San Carlos, Facultad de Medicina, Universidad Complutense, IdiSSC, Madrid, España.
| | - C Oreja-Guevara
- Servicio de Neurología, Hospital Clínico San Carlos, Facultad de Medicina, Universidad Complutense, IdiSSC, Madrid, España
| | - J A Matias-Guiu
- Servicio de Neurología, Hospital Clínico San Carlos, Facultad de Medicina, Universidad Complutense, IdiSSC, Madrid, España
| | - U Gomez-Pinedo
- Servicio de Neurología, Hospital Clínico San Carlos, Facultad de Medicina, Universidad Complutense, IdiSSC, Madrid, España
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Abstract
The neuroendocrine hypothalamus is composed of the tuberal and anterodorsal hypothalamus, together with the median eminence/neurohypophysis. It centrally governs wide-ranging physiological processes, including homeostasis of energy balance, circadian rhythms and stress responses, as well as growth and reproductive behaviours. Homeostasis is maintained by integrating sensory inputs and effecting responses via autonomic, endocrine and behavioural outputs, over diverse time-scales and throughout the lifecourse of an individual. Here, we summarize studies that begin to reveal how different territories and cell types within the neuroendocrine hypothalamus are assembled in an integrated manner to enable function, thus supporting the organism's ability to survive and thrive. We discuss how signaling pathways and transcription factors dictate the appearance and regionalization of the hypothalamic primordium, the maintenance of progenitor cells, and their specification and differentiation into neurons. We comment on recent studies that harness such programmes for the directed differentiation of human ES/iPS cells. We summarize how developmental plasticity is maintained even into adulthood and how integration between the hypothalamus and peripheral body is established in the median eminence and neurohypophysis. Analysis of model organisms, including mouse, chick and zebrafish, provides a picture of how complex, yet elegantly coordinated, developmental programmes build glial and neuronal cells around the third ventricle of the brain. Such conserved processes enable the hypothalamus to mediate its function as a central integrating and response-control mediator for the homeostatic processes that are critical to life. Early indications suggest that deregulation of these events may underlie multifaceted pathological conditions and dysfunctional physiology in humans, such as obesity.
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Affiliation(s)
- Sarah Burbridge
- Bateson Centre and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Iain Stewart
- Bateson Centre and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Marysia Placzek
- Bateson Centre and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
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55
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Christ A, Herzog K, Willnow TE. LRP2, an auxiliary receptor that controls sonic hedgehog signaling in development and disease. Dev Dyn 2016; 245:569-79. [PMID: 26872844 DOI: 10.1002/dvdy.24394] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Revised: 02/03/2016] [Accepted: 02/07/2016] [Indexed: 12/31/2022] Open
Abstract
To fulfill their multiple roles in organ development and adult tissue homeostasis, hedgehog (HH) morphogens act through their receptor Patched (PTCH) on target cells. However, HH actions also require HH binding proteins, auxiliary cell surface receptors that agonize or antagonize morphogen signaling in a context-dependent manner. Here, we discuss recent findings on the LDL receptor-related protein 2 (LRP2), an exemplary HH binding protein that modulates sonic hedgehog activities in stem and progenitor cell niches in embryonic and adult tissues. LRP2 functions are crucial for developmental processes in a number of tissues, including the brain, the eye, and the heart, and defects in this receptor pathway are the cause of devastating congenital diseases in humans. Developmental Dynamics 245:569-579, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Annabel Christ
- Max-Delbrueck-Center for Molecular Medicine, 13125, Berlin, Germany
| | - Katja Herzog
- Max-Delbrueck-Center for Molecular Medicine, 13125, Berlin, Germany
| | - Thomas E Willnow
- Max-Delbrueck-Center for Molecular Medicine, 13125, Berlin, Germany
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56
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Xavier GM, Seppala M, Barrell W, Birjandi AA, Geoghegan F, Cobourne MT. Hedgehog receptor function during craniofacial development. Dev Biol 2016; 415:198-215. [PMID: 26875496 DOI: 10.1016/j.ydbio.2016.02.009] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 02/09/2016] [Accepted: 02/10/2016] [Indexed: 01/20/2023]
Abstract
The Hedgehog signalling pathway plays a fundamental role in orchestrating normal craniofacial development in vertebrates. In particular, Sonic hedgehog (Shh) is produced in three key domains during the early formation of the head; neuroectoderm of the ventral forebrain, facial ectoderm and the pharyngeal endoderm; with signal transduction evident in both ectodermal and mesenchymal tissue compartments. Shh signalling from the prechordal plate and ventral midline of the diencephalon is required for appropriate division of the eyefield and forebrain, with mutation in a number of pathway components associated with Holoprosencephaly, a clinically heterogeneous developmental defect characterized by a failure of the early forebrain vesicle to divide into distinct halves. In addition, signalling from the pharyngeal endoderm and facial ectoderm plays an essential role during development of the face, influencing cranial neural crest cells that migrate into the early facial processes. In recent years, the complexity of Shh signalling has been highlighted by the identification of multiple novel proteins that are involved in regulating both the release and reception of this protein. Here, we review the contributions of Shh signalling during early craniofacial development, focusing on Hedgehog receptor function and describing the consequences of disruption for inherited anomalies of this region in both mouse models and human populations.
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Affiliation(s)
- Guilherme M Xavier
- Department of Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK; Department of Orthodontics, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK
| | - Maisa Seppala
- Department of Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK; Department of Orthodontics, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK
| | - William Barrell
- Department of Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK
| | - Anahid A Birjandi
- Department of Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK
| | - Finn Geoghegan
- Department of Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK
| | - Martyn T Cobourne
- Department of Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK; Department of Orthodontics, King's College London Dental Institute, Floor 27, Guy's Hospital, London SE1 9RT, UK.
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57
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Low Density Lipoprotein Receptor Related Proteins as Regulators of Neural Stem and Progenitor Cell Function. Stem Cells Int 2016; 2016:2108495. [PMID: 26949399 PMCID: PMC4754494 DOI: 10.1155/2016/2108495] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 11/24/2015] [Accepted: 01/06/2016] [Indexed: 12/20/2022] Open
Abstract
The central nervous system (CNS) is a highly organised structure. Many signalling systems work in concert to ensure that neural stem cells are appropriately directed to generate progenitor cells, which in turn mature into functional cell types including projection neurons, interneurons, astrocytes, and oligodendrocytes. Herein we explore the role of the low density lipoprotein (LDL) receptor family, in particular family members LRP1 and LRP2, in regulating the behaviour of neural stem and progenitor cells during development and adulthood. The ability of LRP1 and LRP2 to bind a diverse and extensive range of ligands, regulate ligand endocytosis, recruit nonreceptor tyrosine kinases for direct signal transduction and signal in conjunction with other receptors, enables them to modulate many crucial neural cell functions.
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58
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Grego-Bessa J, Bloomekatz J, Castel P, Omelchenko T, Baselga J, Anderson KV. The tumor suppressor PTEN and the PDK1 kinase regulate formation of the columnar neural epithelium. eLife 2016; 5:e12034. [PMID: 26809587 PMCID: PMC4739759 DOI: 10.7554/elife.12034] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/02/2015] [Indexed: 01/16/2023] Open
Abstract
Epithelial morphogenesis and stability are essential for normal development and organ homeostasis. The mouse neural plate is a cuboidal epithelium that remodels into a columnar pseudostratified epithelium over the course of 24 hr. Here we show that the transition to a columnar epithelium fails in mutant embryos that lack the tumor suppressor PTEN, although proliferation, patterning and apical-basal polarity markers are normal in the mutants. The Pten phenotype is mimicked by constitutive activation of PI3 kinase and is rescued by the removal of PDK1 (PDPK1), but does not depend on the downstream kinases AKT and mTORC1. High resolution imaging shows that PTEN is required for stabilization of planar cell packing in the neural plate and for the formation of stable apical-basal microtubule arrays. The data suggest that appropriate levels of membrane-associated PDPK1 are required for stabilization of apical junctions, which promotes cell elongation, during epithelial morphogenesis.
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Affiliation(s)
- Joaquim Grego-Bessa
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Joshua Bloomekatz
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Pau Castel
- Human Oncology and Pathogenesis Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Tatiana Omelchenko
- Cell Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
| | - José Baselga
- Human Oncology and Pathogenesis Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Kathryn V Anderson
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, United States
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59
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Gui Y, Duan Z, Qiu X, Tang W, Gober HJ, Li D, Wang L. Multifarious effects of 17-β-estradiol on apolipoprotein E receptors gene expression during osteoblast differentiation in vitro . Biosci Trends 2016; 10:54-66. [DOI: 10.5582/bst.2016.01006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Yuyan Gui
- Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases
| | - Zhongliang Duan
- Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases
| | - Xuemin Qiu
- Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases
| | - Wei Tang
- Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, The University of Tokyo
| | - Hans-Jürgen Gober
- Department of Pharmacy, Wagner Jauregg Hospital and Children's Hospital
| | - Dajin Li
- Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College
| | - Ling Wang
- Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College
- Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases
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60
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Landowski LM, Pavez M, Brown LS, Gasperini R, Taylor BV, West AK, Foa L. Low-density Lipoprotein Receptor-related Proteins in a Novel Mechanism of Axon Guidance and Peripheral Nerve Regeneration. J Biol Chem 2015; 291:1092-102. [PMID: 26598525 PMCID: PMC4714193 DOI: 10.1074/jbc.m115.668996] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Indexed: 11/06/2022] Open
Abstract
The low-density lipoprotein receptor-related protein receptors 1 and 2 (LRP1 and LRP2) are emerging as important cell signaling mediators in modulating neuronal growth and repair. We examined whether LRP1 and LRP2 are able to mediate a specific aspect of neuronal growth: axon guidance. We sought to identify LRP1 and LRP2 ligands that could induce axonal chemoattraction, which might have therapeutic potential. Using embryonic sensory neurons (rat dorsal root ganglia) in a growth cone turning assay, we tested a range of LRP1 and LRP2 ligands for the ability to guide growth cone navigation. Three ligands were chemorepulsive: α-2-macroglobulin, tissue plasminogen activator, and metallothionein III. Conversely, only one LRP ligand, metallothionein II, was found to be chemoattractive. Chemoattraction toward a gradient of metallothionein II was calcium-dependent, required the expression of both LRP1 and LRP2, and likely involves further co-receptors such as the tropomyosin-related kinase A (TrkA) receptor. The potential for LRP-mediated chemoattraction to mediate axonal regeneration was examined in vivo in a model of chemical denervation in adult rats. In these in vivo studies, metallothionein II was shown to enhance epidermal nerve fiber regeneration so that it was complete within 7 days compared with 14 days in saline-treated animals. Our data demonstrate that both LRP1 and LRP2 are necessary for metallothionein II-mediated chemotactic signal transduction and that they may form part of a signaling complex. Furthermore, the data suggest that LRP-mediated chemoattraction represents a novel, non-classical signaling system that has therapeutic potential as a disease-modifying agent for the injured peripheral nervous system.
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Affiliation(s)
- Lila M Landowski
- From the School of Medicine and Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania 7001, Australia
| | | | | | - Robert Gasperini
- From the School of Medicine and Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - Bruce V Taylor
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania 7001, Australia
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61
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Moffat JJ, Ka M, Jung EM, Kim WY. Genes and brain malformations associated with abnormal neuron positioning. Mol Brain 2015; 8:72. [PMID: 26541977 PMCID: PMC4635534 DOI: 10.1186/s13041-015-0164-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 10/31/2015] [Indexed: 01/05/2023] Open
Abstract
Neuronal positioning is a fundamental process during brain development. Abnormalities in this process cause several types of brain malformations and are linked to neurodevelopmental disorders such as autism, intellectual disability, epilepsy, and schizophrenia. Little is known about the pathogenesis of developmental brain malformations associated with abnormal neuron positioning, which has hindered research into potential treatments. However, recent advances in neurogenetics provide clues to the pathogenesis of aberrant neuronal positioning by identifying causative genes. This may help us form a foundation upon which therapeutic tools can be developed. In this review, we first provide a brief overview of neural development and migration, as they relate to defects in neuronal positioning. We then discuss recent progress in identifying genes and brain malformations associated with aberrant neuronal positioning during human brain development.
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Affiliation(s)
- Jeffrey J Moffat
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
| | - Minhan Ka
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
| | - Eui-Man Jung
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
| | - Woo-Yang Kim
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
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62
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Christ A, Christa A, Klippert J, Eule JC, Bachmann S, Wallace VA, Hammes A, Willnow TE. LRP2 Acts as SHH Clearance Receptor to Protect the Retinal Margin from Mitogenic Stimuli. Dev Cell 2015; 35:36-48. [PMID: 26439398 DOI: 10.1016/j.devcel.2015.09.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 08/21/2015] [Accepted: 09/07/2015] [Indexed: 01/17/2023]
Abstract
During forebrain development, LRP2 promotes morphogen signaling as an auxiliary SHH receptor. However, in the developing retina, LRP2 assumes the opposing function, mediating endocytic clearance of SHH and antagonizing morphogen action. LRP2-mediated clearance prevents spread of SHH activity from the central retina into the retinal margin to protect quiescent progenitor cells in this niche from mitogenic stimuli. Loss of LRP2 in mice increases the sensitivity of the retinal margin for SHH, causing expansion of the retinal progenitor cell pool and hyperproliferation of this tissue. Our findings document the ability of LRP2 to act, in a context-dependent manner, as activator or inhibitor of the SHH pathway. Our current findings uncovered LRP2 activity as the molecular mechanism imposing quiescence of the retinal margin in the mammalian eye and suggest SHH-induced proliferation of the retinal margin as cause of the large eye phenotype observed in mouse models and patients with LRP2 defects.
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Affiliation(s)
- Annabel Christ
- Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin, Germany.
| | - Anna Christa
- Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin, Germany
| | - Julia Klippert
- Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin, Germany
| | - J Corinna Eule
- Small Animal Clinic, Free University Berlin, 14163 Berlin, Germany
| | - Sebastian Bachmann
- Institute for Vegetative Anatomy, Charité University Medicine Berlin, 10117 Berlin, Germany
| | - Valerie A Wallace
- Toronto Western Research Institute, University Health Network, Toronto, ON M5T 2S8, Canada
| | - Annette Hammes
- Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin, Germany
| | - Thomas E Willnow
- Max-Delbrueck-Center for Molecular Medicine, 13125 Berlin, Germany.
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63
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Cases O, Joseph A, Obry A, Santin MD, Ben-Yacoub S, Pâques M, Amsellem-Levera S, Bribian A, Simonutti M, Augustin S, Debeir T, Sahel JA, Christ A, de Castro F, Lehéricy S, Cosette P, Kozyraki R. Foxg1-Cre Mediated Lrp2 Inactivation in the Developing Mouse Neural Retina, Ciliary and Retinal Pigment Epithelia Models Congenital High Myopia. PLoS One 2015; 10:e0129518. [PMID: 26107939 PMCID: PMC4480972 DOI: 10.1371/journal.pone.0129518] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 05/08/2015] [Indexed: 12/11/2022] Open
Abstract
Myopia is a common ocular disorder generally due to increased axial length of the eye-globe. Its extreme form high myopia (HM) is a multifactorial disease leading to retinal and scleral damage, visual impairment or loss and is an important health issue. Mutations in the endocytic receptor LRP2 gene result in Donnai-Barrow (DBS) and Stickler syndromes, both characterized by HM. To clearly establish the link between Lrp2 and congenital HM we inactivated Lrp2 in the mouse forebrain including the neural retina and the retinal and ciliary pigment epithelia. High resolution in vivo MRI imaging and ophthalmological analyses showed that the adult Lrp2-deficient eyes were 40% longer than the control ones mainly due to an excessive elongation of the vitreal chamber. They had an apparently normal intraocular pressure and developed chorioretinal atrophy and posterior scleral staphyloma features reminiscent of human myopic retinopathy. Immunomorphological and ultrastructural analyses showed that increased eye lengthening was first observed by post-natal day 5 (P5) and that it was accompanied by a rapid decrease of the bipolar, photoreceptor and retinal ganglion cells, and eventually the optic nerve axons. It was followed by scleral thinning and collagen fiber disorganization, essentially in the posterior pole. We conclude that the function of LRP2 in the ocular tissues is necessary for normal eye growth and that the Lrp2-deficient eyes provide a unique tool to further study human HM.
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Affiliation(s)
- Olivier Cases
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
| | - Antoine Joseph
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
| | - Antoine Obry
- CNRS, UMR_6270, PISSARO Proteomics Platform, Institute for Research and Innovation in Biomedicine, Rouen University Hospital, Rouen, F-76821, France
- INSERM, U905, PISSARO Proteomics Platform, Institute for Research and Innovation in Biomedicine, Rouen University Hospital, Rouen, F-76821, France
| | | | - Sirine Ben-Yacoub
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
| | - Michel Pâques
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
- Centre Hospitalier National d’Ophthalmologie des Quinze-Vingts, INSERM-DHOS CIC 503, Paris, F-75012, France
| | - Sabine Amsellem-Levera
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
| | - Ana Bribian
- Grupo de Neurobiologia del Desarollo-GNDe, Hospital Nacional de Parapléjicos, Toledo, Spain
| | - Manuel Simonutti
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
| | - Sébastien Augustin
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
| | | | - José Alain Sahel
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
- Centre Hospitalier National d’Ophthalmologie des Quinze-Vingts, INSERM-DHOS CIC 503, Paris, F-75012, France
| | - Annabel Christ
- Max-Delbrück-Center for Molecular Medicine, Berlin, D-13125, Germany
| | - Fernando de Castro
- Grupo de Neurobiologia del Desarollo-GNDe, Hospital Nacional de Parapléjicos, Toledo, Spain
| | | | - Pascal Cosette
- CNRS, UMR_6270, PISSARO Proteomics Platform, Institute for Research and Innovation in Biomedicine, Rouen University Hospital, Rouen, F-76821, France
| | - Renata Kozyraki
- INSERM, U968, Paris, F-75012, France
- UPMC Univ Paris 06, UMR_S968, Institut de la Vision, Paris, F-75012, France
- CNRS, UMR_7210, Paris, F-75012, France
- * E-mail:
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64
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Song JY, Holtz AM, Pinskey JM, Allen BL. Distinct structural requirements for CDON and BOC in the promotion of Hedgehog signaling. Dev Biol 2015; 402:239-52. [PMID: 25848697 DOI: 10.1016/j.ydbio.2015.03.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 03/03/2015] [Accepted: 03/25/2015] [Indexed: 01/20/2023]
Abstract
Proper levels of Hedgehog (HH) signaling are essential during embryonic development and adult tissue homeostasis. A central mechanism to control HH pathway activity is through the regulation of secreted HH ligands at the plasma membrane. Recent studies have revealed a collective requirement for the cell surface co-receptors GAS1, CDON and BOC in HH signal transduction. Despite their requirement in HH pathway function, the mechanisms by which these proteins act to promote HH signaling remain poorly understood. Here we focus on the function of the two structurally related co-receptors, CDON and BOC. We utilized an in vivo gain-of-function approach in the developing chicken spinal cord to dissect the structural requirements for CDON and BOC function in HH signal transduction. Notably, we find that although CDON and BOC display functional redundancy during HH-dependent ventral neural patterning, these molecules utilize distinct molecular mechanisms to execute their HH-promoting effects. Specifically, we define distinct membrane attachment requirements for CDON and BOC function in HH signal transduction. Further, we identify novel and separate extracellular motifs in CDON and BOC that are required to promote HH signaling. Together, these data suggest that HH co-receptors employ distinct mechanisms to mediate HH pathway activity.
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Affiliation(s)
- Jane Y Song
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Alexander M Holtz
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA; Medical Scientist Training Program, University of Michigan, Ann Arbor, MI 48109, USA; Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - Justine M Pinskey
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Benjamin L Allen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
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65
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Blaess S, Szabó N, Haddad-Tóvolli R, Zhou X, Álvarez-Bolado G. Sonic hedgehog signaling in the development of the mouse hypothalamus. Front Neuroanat 2015; 8:156. [PMID: 25610374 PMCID: PMC4285088 DOI: 10.3389/fnana.2014.00156] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 12/02/2014] [Indexed: 11/13/2022] Open
Abstract
The expression pattern of Sonic Hedgehog (Shh) in the developing hypothalamus changes over time. Shh is initially expressed in the prechordal mesoderm and later in the hypothalamic neuroepithelium—first medially, and then in two off-medial domains. This dynamic expression suggests that Shh might regulate several aspects of hypothalamic development. To gain insight into them, lineage tracing, (conditional) gene inactivation in mouse, in ovo loss- and gain-of-function approaches in chick and analysis of Shh expression regulation have been employed. We will focus on mouse studies and refer to chick and fish when appropriate to clarify. These studies show that Shh-expressing neuroepithelial cells serve as a signaling center for neighboring precursors, and give rise to most of the basal hypothalamus (tuberal and mammillary regions). Shh signaling is initially essential for hypothalamic induction. Later, Shh signaling from the neuroepithelium controls specification of the lateral hypothalamic area and growth-patterning coordination in the basal hypothalamus. To further elucidate the role of Shh in hypothalamic development, it will be essential to understand how Shh regulates the downstream Gli transcription factors.
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Affiliation(s)
- Sandra Blaess
- Neurodevelopmental Genetics, Institute of Reconstructive Neurobiology, University of Bonn Bonn, Germany
| | - Nora Szabó
- Department of Neurobiology and Development, Institut de Recherches Cliniques de Montréal Montréal, QC, Canada
| | - Roberta Haddad-Tóvolli
- Department of Medical Cell Biology, Institute of Anatomy and Cell Biology, University of Heidelberg Heidelberg, Germany
| | - Xunlei Zhou
- Department of Medical Cell Biology, Institute of Anatomy and Cell Biology, University of Heidelberg Heidelberg, Germany
| | - Gonzalo Álvarez-Bolado
- Department of Medical Cell Biology, Institute of Anatomy and Cell Biology, University of Heidelberg Heidelberg, Germany
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66
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Abstract
Members of the low-density lipoprotein (LDL) receptor gene family have a diverse set of biological functions that transcend lipid metabolism. Lipoprotein receptors have broad effects in both the developing and adult brain and participate in synapse development, cargo trafficking, and signal transduction. In addition, several family members play key roles in Alzheimer's disease (AD) pathogenesis and neurodegeneration. This Review summarizes our current understanding of the role lipoprotein receptors play in CNS function and AD pathology, with a special emphasis on amyloid-independent roles in endocytosis and synaptic dysfunction.
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67
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Vyas N, Walvekar A, Tate D, Lakshmanan V, Bansal D, Lo Cicero A, Raposo G, Palakodeti D, Dhawan J. Vertebrate Hedgehog is secreted on two types of extracellular vesicles with different signaling properties. Sci Rep 2014; 4:7357. [PMID: 25483805 PMCID: PMC4258658 DOI: 10.1038/srep07357] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 11/18/2014] [Indexed: 12/29/2022] Open
Abstract
Hedgehog (Hh) is a secreted morphogen that elicits differentiation and patterning in developing tissues. Multiple proposed mechanisms to regulate Hh dispersion includes lipoprotein particles and exosomes. Here we report that vertebrate Sonic Hedgehog (Shh) is secreted on two types of extracellular-vesicles/exosomes, from human cell lines and primary chick notochord cells. Although largely overlapping in size as estimated from electron micrographs, the two exosomal fractions exhibited distinct protein and RNA composition. We have probed the functional properties of these vesicles using cell-based assays of Hh-elicited gene expression. Our results suggest that while both Shh-containing exo-vesicular fractions can activate an ectopic Gli-luciferase construct, only exosomes co-expressing Integrins can activate endogenous Shh target genes HNF3β and Olig2 during the differentiation of mouse ES cells to ventral neuronal progenitors. Taken together, our results demonstrate that primary vertebrate cells secrete Shh in distinct vesicular forms, and support a model where packaging of Shh along with other signaling proteins such as Integrins on exosomes modulates target gene activation. The existence of distinct classes of Shh-containing exosomes also suggests a previously unappreciated complexity for fine-tuning of Shh-mediated gradients and pattern formation.
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Affiliation(s)
- Neha Vyas
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India
| | - Ankita Walvekar
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India
| | - Dhananjay Tate
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India
| | | | - Dhiru Bansal
- Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India
| | - Alessandra Lo Cicero
- 1] Institut Curie, UMR 144, CNRS, F-75248 Paris, France [2] Structure and Membrane Compartments, Centre National de la Recherche Scientifique, UMR144, Paris F-75248, France [3] Cell and Tissue Imaging Facility, Infrastructures en Biologie Sante et Agronomie (IBiSA), Paris F-75248, France
| | - Graca Raposo
- 1] Institut Curie, UMR 144, CNRS, F-75248 Paris, France [2] Structure and Membrane Compartments, Centre National de la Recherche Scientifique, UMR144, Paris F-75248, France [3] Cell and Tissue Imaging Facility, Infrastructures en Biologie Sante et Agronomie (IBiSA), Paris F-75248, France
| | | | - Jyotsna Dhawan
- 1] Institute for Stem Cell Biology and Regenerative Medicine, Bangalore, India [2] CSIR-Center for Cellular and Molecular Biology, Hyderabad, India
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68
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Teperino R, Aberger F, Esterbauer H, Riobo N, Pospisilik JA. Canonical and non-canonical Hedgehog signalling and the control of metabolism. Semin Cell Dev Biol 2014; 33:81-92. [PMID: 24862854 DOI: 10.1016/j.semcdb.2014.05.007] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 05/07/2014] [Accepted: 05/08/2014] [Indexed: 02/07/2023]
Abstract
Obesity and diabetes represent key healthcare challenges of our day, affecting upwards of one billion people worldwide. These individuals are at higher risk for cancer, stroke, blindness, heart and cardiovascular disease, and to date, have no effective long-term treatment options available. Recent and accumulating evidence has implicated the developmental morphogen Hedgehog and its downstream signalling in metabolic control. Generally thought to be quiescent in adults, Hedgehog is associated with several human cancers, and as such, has already emerged as a therapeutic target in oncology. Here, we attempt to give a comprehensive overview of the key signalling events associated with both canonical and non-canonical Hedgehog signalling, and highlight the increasingly complex regulatory modalities that appear to link Hedgehog and control metabolism. We highlight these key findings and discuss their impact for therapeutic development, cancer and metabolic disease.
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Affiliation(s)
- Raffaele Teperino
- Department of Epigenetics, Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany
| | - Fritz Aberger
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Harald Esterbauer
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Natalia Riobo
- Department of Biochemistry and Molecular Biology and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - John Andrew Pospisilik
- Department of Epigenetics, Max-Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany.
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69
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Kur E, Mecklenburg N, Cabrera RM, Willnow TE, Hammes A. LRP2 mediates folate uptake in the developing neural tube. J Cell Sci 2014; 127:2261-8. [PMID: 24639464 DOI: 10.1242/jcs.140145] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The low-density lipoprotein (LDL) receptor-related protein 2 (LRP2) is a multifunctional cell-surface receptor expressed in the embryonic neuroepithelium. Loss of LRP2 in the developing murine central nervous system (CNS) causes impaired closure of the rostral neural tube at embryonic stage (E) 9.0. Similar neural tube defects (NTDs) have previously been attributed to impaired folate metabolism in mice. We therefore asked whether LRP2 might be required for the delivery of folate to neuroepithelial cells during neurulation. Uptake assays in whole-embryo cultures showed that LRP2-deficient neuroepithelial cells are unable to mediate the uptake of folate bound to soluble folate receptor 1 (sFOLR1). Consequently, folate concentrations are significantly reduced in Lrp2(-/-) embryos compared with control littermates. Moreover, the folic-acid-dependent gene Alx3 is significantly downregulated in Lrp2 mutants. In conclusion, we show that LRP2 is essential for cellular folate uptake in the developing neural tube, a crucial step for proper neural tube closure.
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Affiliation(s)
- Esther Kur
- Max Delbrück Center for Molecular Medicine (MDC), Robert Rössle Strasse 10, 13125 Berlin, Germany
| | - Nora Mecklenburg
- Max Delbrück Center for Molecular Medicine (MDC), Robert Rössle Strasse 10, 13125 Berlin, Germany
| | - Robert M Cabrera
- Department of Nutritional Sciences, Dell Pediatric Research Institute, The University of Texas at Austin, Austin, TX 78723, USA
| | - Thomas E Willnow
- Max Delbrück Center for Molecular Medicine (MDC), Robert Rössle Strasse 10, 13125 Berlin, Germany
| | - Annette Hammes
- Max Delbrück Center for Molecular Medicine (MDC), Robert Rössle Strasse 10, 13125 Berlin, Germany
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70
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Edwards TJ, Sherr EH, Barkovich AJ, Richards LJ. Clinical, genetic and imaging findings identify new causes for corpus callosum development syndromes. ACTA ACUST UNITED AC 2014; 137:1579-613. [PMID: 24477430 DOI: 10.1093/brain/awt358] [Citation(s) in RCA: 215] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The corpus callosum is the largest fibre tract in the brain, connecting the two cerebral hemispheres, and thereby facilitating the integration of motor and sensory information from the two sides of the body as well as influencing higher cognition associated with executive function, social interaction and language. Agenesis of the corpus callosum is a common brain malformation that can occur either in isolation or in association with congenital syndromes. Understanding the causes of this condition will help improve our knowledge of the critical brain developmental mechanisms required for wiring the brain and provide potential avenues for therapies for callosal agenesis or related neurodevelopmental disorders. Improved genetic studies combined with mouse models and neuroimaging have rapidly expanded the diverse collection of copy number variations and single gene mutations associated with callosal agenesis. At the same time, advances in our understanding of the developmental mechanisms involved in corpus callosum formation have provided insights into the possible causes of these disorders. This review provides the first comprehensive classification of the clinical and genetic features of syndromes associated with callosal agenesis, and provides a genetic and developmental framework for the interpretation of future research that will guide the next advances in the field.
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Affiliation(s)
- Timothy J Edwards
- 1 Queensland Brain Institute, The University of Queensland, Brisbane, 4072, Australia2 Departments of Neurology and Pediatrics, The University of California and the Benioff Children's Hospital, CA, 94158, USA
| | - Elliott H Sherr
- 3 Departments of Pediatrics and Neurosurgery, Radiology and Biomedical Imaging, The University of California Children's Hospital, CA 94143, USA
| | - A James Barkovich
- 3 Departments of Pediatrics and Neurosurgery, Radiology and Biomedical Imaging, The University of California Children's Hospital, CA 94143, USA4 Departments of Paediatrics and Neurosurgery, Radiology and Biomedical Imaging, The University of California San Francisco and The Benioff Children's Hospital, CA 94143-0628 USA
| | - Linda J Richards
- 1 Queensland Brain Institute, The University of Queensland, Brisbane, 4072, Australia5 School of Biomedical Sciences, The University of Queensland, Brisbane, 4072, Australia
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71
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Holtz AM, Peterson KA, Nishi Y, Morin S, Song JY, Charron F, McMahon AP, Allen BL. Essential role for ligand-dependent feedback antagonism of vertebrate hedgehog signaling by PTCH1, PTCH2 and HHIP1 during neural patterning. Development 2013; 140:3423-34. [PMID: 23900540 DOI: 10.1242/dev.095083] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Hedgehog (HH) signaling is essential for vertebrate and invertebrate embryogenesis. In Drosophila, feedback upregulation of the HH receptor Patched (PTC; PTCH in vertebrates), is required to restrict HH signaling during development. By contrast, PTCH1 upregulation is dispensable for early HH-dependent patterning in mice. Unique to vertebrates are two additional HH-binding antagonists that are induced by HH signaling, HHIP1 and the PTCH1 homologue PTCH2. Although HHIP1 functions semi-redundantly with PTCH1 to restrict HH signaling in the developing nervous system, a role for PTCH2 remains unresolved. Data presented here define a novel role for PTCH2 as a ciliary localized HH pathway antagonist. While PTCH2 is dispensable for normal ventral neural patterning, combined removal of PTCH2- and PTCH1-feedback antagonism produces a significant expansion of HH-dependent ventral neural progenitors. Strikingly, complete loss of PTCH2-, HHIP1- and PTCH1-feedback inhibition results in ectopic specification of ventral cell fates throughout the neural tube, reflecting constitutive HH pathway activation. Overall, these data reveal an essential role for ligand-dependent feedback inhibition of vertebrate HH signaling governed collectively by PTCH1, PTCH2 and HHIP1.
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Affiliation(s)
- Alexander M Holtz
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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72
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Ha S, Stottmann RW, Furley AJ, Beier DR. A forward genetic screen in mice identifies mutants with abnormal cortical patterning. ACTA ACUST UNITED AC 2013; 25:167-79. [PMID: 23968836 DOI: 10.1093/cercor/bht209] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Formation of a 6-layered cortical plate and axon tract patterning are key features of cerebral cortex development. Abnormalities of these processes may be the underlying cause for a range of functional disabilities seen in human neurodevelopmental disorders. To identify mouse mutants with defects in cortical lamination or corticofugal axon guidance, N-ethyl-N-nitrosourea (ENU) mutagenesis was performed using mice expressing LacZ reporter genes in layers II/III and V of the cortex (Rgs4-lacZ) or in corticofugal axons (TAG1-tau-lacZ). Four lines with abnormal cortical lamination have been identified. One of these was a splice site mutation in reelin (Reln) that results in a premature stop codon and the truncation of the C-terminal region (CTR) domain of reelin. Interestingly, this novel allele of Reln did not display cerebellar malformation or ataxia, and this is the first report of a Reln mutant without a cerebellar defect. Four lines with abnormal cortical axon development were also identified, one of which was found by whole-genome resequencing to carry a mutation in Lrp2. These findings demonstrated that the application of ENU mutagenesis to mice carrying transgenic reporters marking cortical anatomy is a sensitive and specific method to identify mutations that disrupt patterning of the developing brain.
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Affiliation(s)
- Seungshin Ha
- Genetics Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, WA 98101, USA
| | - Rolf W Stottmann
- Genetics Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA Divisions of Human Genetics and Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA and
| | - Andrew J Furley
- Department of Biomedical Science, The University of Sheffield, Western Bank, Sheffield S10 2TN, UK
| | - David R Beier
- Genetics Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA Center for Developmental Biology and Regenerative Medicine, Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, WA 98101, USA
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73
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Frattini V, Trifonov V, Chan JM, Castano A, Lia M, Abate F, Keir ST, Ji AX, Zoppoli P, Niola F, Danussi C, Dolgalev I, Porrati P, Pellegatta S, Heguy A, Gupta G, Pisapia DJ, Canoll P, Bruce JN, McLendon RE, Yan H, Aldape K, Finocchiaro G, Mikkelsen T, Privé GG, Bigner DD, Lasorella A, Rabadan R, Iavarone A. The integrated landscape of driver genomic alterations in glioblastoma. Nat Genet 2013; 45:1141-9. [PMID: 23917401 PMCID: PMC3799953 DOI: 10.1038/ng.2734] [Citation(s) in RCA: 408] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 07/29/2013] [Indexed: 12/12/2022]
Abstract
Glioblastoma is one of the most challenging forms of cancer to treat. Here we describe a computational platform that integrates the analysis of copy number variations and somatic mutations and unravels the landscape of in-frame gene fusions in glioblastoma. We found mutations with loss of heterozygosity in LZTR1, encoding an adaptor of CUL3-containing E3 ligase complexes. Mutations and deletions disrupt LZTR1 function, which restrains the self renewal and growth of glioma spheres that retain stem cell features. Loss-of-function mutations in CTNND2 target a neural-specific gene and are associated with the transformation of glioma cells along the very aggressive mesenchymal phenotype. We also report recurrent translocations that fuse the coding sequence of EGFR to several partners, with EGFR-SEPT14 being the most frequent functional gene fusion in human glioblastoma. EGFR-SEPT14 fusions activate STAT3 signaling and confer mitogen independence and sensitivity to EGFR inhibition. These results provide insights into the pathogenesis of glioblastoma and highlight new targets for therapeutic intervention.
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Affiliation(s)
- Veronique Frattini
- 1] Institute for Cancer Genetics, Columbia University Medical Center, New York, New York, USA. [2]
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74
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Shh/Boc signaling is required for sustained generation of ipsilateral projecting ganglion cells in the mouse retina. J Neurosci 2013; 33:8596-607. [PMID: 23678105 DOI: 10.1523/jneurosci.2083-12.2013] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Sonic Hedgehog (Shh) signaling is an important determinant of vertebrate retinal ganglion cell (RGC) development. In mice, there are two major RGC populations: (1) the Islet2-expressing contralateral projecting (c)RGCs, which both produce and respond to Shh; and (2) the Zic2-expressing ipsilateral projecting RGCs (iRGCs), which lack Shh expression. In contrast to cRGCs, iRGCs, which are generated in the ventrotemporal crescent (VTC) of the retina, specifically express Boc, a cell adhesion molecule that acts as a high-affinity receptor for Shh. In Boc(-/-) mutant mice, the ipsilateral projection is significantly decreased. Here, we demonstrate that this phenotype results, at least in part, from the misspecification of a proportion of iRGCs. In Boc(-/-) VTC, the number of Zic2-positive RGCs is reduced, whereas more Islet2/Shh-positive RGCs are observed, a phenotype also detected in Zic2 and Foxd1 null embryos. Consistent with this observation, organization of retinal projections at the dorsal lateral geniculate nucleus is altered in Boc(-/-) mice. Analyses of the molecular and cellular consequences of introducing Shh into the developing VTC and Zic2 and Boc into the central retina indicate that Boc expression alone is insufficient to fully activate the ipsilateral program and that Zic2 regulates Shh expression. Taking these data together, we propose that expression of Boc in cells from the VTC is required to sustain Zic2 expression, likely by regulating the levels of Shh signaling from the nearby cRGCs. Zic2, in turn, directly or indirectly, counteracts Shh and Islet2 expression in the VTC and activates the ipsilateral program.
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75
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Andersen OM, Dagil R, Kragelund BB. New horizons for lipoprotein receptors: communication by β-propellers. J Lipid Res 2013; 54:2763-74. [PMID: 23881912 DOI: 10.1194/jlr.m039545] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The lipoprotein receptor (LR) family constitutes a large group of structurally closely related receptors with broad ligand-binding specificity. Traditionally, ligand binding to LRs has been anticipated to involve merely the complement type repeat (CR)-domains omnipresent in the family. Recently, this dogma has transformed with the observation that β-propellers of some LRs actively engage in complex formation too. Based on an in-depth decomposition of current structures and sequences, we suggest that exploitation of the β-propellers as binding targets depends on receptor subgroups. In particular, we highlight the shutter mechanism of β-propellers as a general recognition motif for NxI-containing ligands, and we present indications that the generalized β-propeller-induced ligand release mechanism is not applicable for the larger LRs. For the giant LR members, we present evidence that their β-propellers may also actively engage in ligand binding. We therefore advocate for an increased focus on solving the structure-function relationship of this group of important biological receptors.
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Affiliation(s)
- Olav M Andersen
- Department of Biomedicine, Aarhus University, DK-8000 Aarhus C, Denmark; and
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76
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Carpentier S, N'Kuli F, Grieco G, Van Der Smissen P, Janssens V, Emonard H, Bilanges B, Vanhaesebroeck B, Gaide Chevronnay HP, Pierreux CE, Tyteca D, Courtoy PJ. Class III phosphoinositide 3-kinase/VPS34 and dynamin are critical for apical endocytic recycling. Traffic 2013; 14:933-48. [PMID: 23621784 DOI: 10.1111/tra.12079] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 04/23/2013] [Accepted: 04/26/2013] [Indexed: 12/27/2022]
Abstract
Recycling is a limiting step for receptor-mediated endocytosis. We first report three in vitro or in vivo evidences that class III PI3K/VPS34 is the key PI3K isoform regulating apical recycling. A substractive approach, comparing in Opossum Kidney (OK) cells a pan-class I/II/III PI3K inhibitor (LY294002) with a class I/II PI3K inhibitor (ZSTK474), suggested that class III PI3K/VPS34 inhibition induced selective apical endosome swelling and sequestration of the endocytic receptor, megalin/LRP-2, causing surface down-regulation. GFP-(FYVE)x2 overexpression to sequester PI(3)P caused undistinguishable apical endosome swelling. In mouse kidney proximal tubular cells, conditional Vps34 inactivation also led to vacuolation and intracellular megalin redistribution. We next report that removal of LY294002 from LY294002-treated OK cells induced a spectacular burst of recycling tubules and restoration of megalin surface pool. Acute triggering of recycling tubules revealed recruitment of dynamin-GFP and dependence of dynamin-GTPase, guidance directionality by microtubules, and suggested that a microfilamentous net constrained endosomal swelling. We conclude that (i) besides its role in endosome fusion, PI3K-III is essential for endosome fission/recycling; and (ii) besides its role in endocytic entry, dynamin also supports tubulation of recycling endosomes. The unleashing of recycling upon acute reversal of PI3K inhibition may help study its dynamics and associated machineries.
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Affiliation(s)
- Sarah Carpentier
- CELL Unit, Université catholique de Louvain & de Duve Institute, Brussels, Belgium
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77
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Briscoe J, Thérond PP. The mechanisms of Hedgehog signalling and its roles in development and disease. Nat Rev Mol Cell Biol 2013; 14:416-29. [DOI: 10.1038/nrm3598] [Citation(s) in RCA: 1212] [Impact Index Per Article: 110.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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78
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Cases O, Perea-Gomez A, Aguiar DP, Nykjaer A, Amsellem S, Chandellier J, Umbhauer M, Cereghini S, Madsen M, Collignon J, Verroust P, Riou JF, Creuzet SE, Kozyraki R. Cubilin, a high affinity receptor for fibroblast growth factor 8, is required for cell survival in the developing vertebrate head. J Biol Chem 2013; 288:16655-16670. [PMID: 23592779 DOI: 10.1074/jbc.m113.451070] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cubilin (Cubn) is a multiligand endocytic receptor critical for the intestinal absorption of vitamin B12 and renal protein reabsorption. During mouse development, Cubn is expressed in both embryonic and extra-embryonic tissues, and Cubn gene inactivation results in early embryo lethality most likely due to the impairment of the function of extra-embryonic Cubn. Here, we focus on the developmental role of Cubn expressed in the embryonic head. We report that Cubn is a novel, interspecies-conserved Fgf receptor. Epiblast-specific inactivation of Cubn in the mouse embryo as well as Cubn silencing in the anterior head of frog or the cephalic neural crest of chick embryos show that Cubn is required during early somite stages to convey survival signals in the developing vertebrate head. Surface plasmon resonance analysis reveals that fibroblast growth factor 8 (Fgf8), a key mediator of cell survival, migration, proliferation, and patterning in the developing head, is a high affinity ligand for Cubn. Cell uptake studies show that binding to Cubn is necessary for the phosphorylation of the Fgf signaling mediators MAPK and Smad1. Although Cubn may not form stable ternary complexes with Fgf receptors (FgfRs), it acts together with and/or is necessary for optimal FgfR activity. We propose that plasma membrane binding of Fgf8, and most likely of the Fgf8 family members Fgf17 and Fgf18, to Cubn improves Fgf ligand endocytosis and availability to FgfRs, thus modulating Fgf signaling activity.
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Affiliation(s)
- Olivier Cases
- Institut de la Vision, INSERM U968, CNRS UMR7210, Université Pierre et Marie Curie UMRS968, 17 Rue Moreau, F-75012 Paris, France
| | - Aitana Perea-Gomez
- Institut Jacques Monod, CNRS UMR7592, Université Paris Diderot, Sorbonne Paris Cité, 15 Rue Hélène Brion, F-75205 Paris, France
| | - Diego P Aguiar
- Institut de Neurobiologie Alfred-Fessard, CNRS UPR3294, Développement, Evolution et Plasticité du Système Nerveux, F-91198 Gif-sur-Yvette, France
| | - Anders Nykjaer
- Lundbeck Foundation Research Centre MIND, Department of Biomedicine, University of Aarhus, Olle Worms Allé 3, 8000 Aarhus, Denmark
| | - Sabine Amsellem
- Institut de la Vision, INSERM U968, CNRS UMR7210, Université Pierre et Marie Curie UMRS968, 17 Rue Moreau, F-75012 Paris, France
| | - Jacqueline Chandellier
- Institut de la Vision, INSERM U968, CNRS UMR7210, Université Pierre et Marie Curie UMRS968, 17 Rue Moreau, F-75012 Paris, France
| | - Muriel Umbhauer
- CNRS UMR7622, Laboratoire de Biologie du Développement, Université Pierre et Marie Curie, 9 Quai Saint Bernard, F-75252 Paris, France
| | - Silvia Cereghini
- CNRS UMR7622, Laboratoire de Biologie du Développement, Université Pierre et Marie Curie, 9 Quai Saint Bernard, F-75252 Paris, France
| | - Mette Madsen
- Department of Biomedicine, University of Aarhus, Olle Worms Allé 3, 8000 Aarhus, Denmark
| | - Jérôme Collignon
- Institut Jacques Monod, CNRS UMR7592, Université Paris Diderot, Sorbonne Paris Cité, 15 Rue Hélène Brion, F-75205 Paris, France
| | - Pierre Verroust
- Institut de la Vision, INSERM U968, CNRS UMR7210, Université Pierre et Marie Curie UMRS968, 17 Rue Moreau, F-75012 Paris, France
| | - Jean-François Riou
- CNRS UMR7622, Laboratoire de Biologie du Développement, Université Pierre et Marie Curie, 9 Quai Saint Bernard, F-75252 Paris, France
| | - Sophie E Creuzet
- Institut de Neurobiologie Alfred-Fessard, CNRS UPR3294, Développement, Evolution et Plasticité du Système Nerveux, F-91198 Gif-sur-Yvette, France
| | - Renata Kozyraki
- Institut de la Vision, INSERM U968, CNRS UMR7210, Université Pierre et Marie Curie UMRS968, 17 Rue Moreau, F-75012 Paris, France.
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79
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Palm W, Swierczynska MM, Kumari V, Ehrhart-Bornstein M, Bornstein SR, Eaton S. Secretion and signaling activities of lipoprotein-associated hedgehog and non-sterol-modified hedgehog in flies and mammals. PLoS Biol 2013; 11:e1001505. [PMID: 23554573 PMCID: PMC3595218 DOI: 10.1371/journal.pbio.1001505] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 01/31/2013] [Indexed: 12/13/2022] Open
Abstract
Hedgehog (Hh) proteins control animal development and tissue homeostasis. They activate gene expression by regulating processing, stability, and activation of Gli/Cubitus interruptus (Ci) transcription factors. Hh proteins are secreted and spread through tissue, despite becoming covalently linked to sterol during processing. Multiple mechanisms have been proposed to release Hh proteins in distinct forms; in Drosophila, lipoproteins facilitate long-range Hh mobilization but also contain lipids that repress the pathway. Here, we show that mammalian lipoproteins have conserved roles in Sonic Hedgehog (Shh) release and pathway repression. We demonstrate that lipoprotein-associated forms of Hh and Shh specifically block lipoprotein-mediated pathway inhibition. We also identify a second conserved release form that is not sterol-modified and can be released independently of lipoproteins (Hh-N*/Shh-N*). Lipoprotein-associated Hh/Shh and Hh-N*/Shh-N* have complementary and synergistic functions. In Drosophila wing imaginal discs, lipoprotein-associated Hh increases the amount of full-length Ci, but is insufficient for target gene activation. However, small amounts of non-sterol-modified Hh synergize with lipoprotein-associated Hh to fully activate the pathway and allow target gene expression. The existence of Hh secretion forms with distinct signaling activities suggests a novel mechanism for generating a diversity of Hh responses.
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Affiliation(s)
- Wilhelm Palm
- Max-Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Marta M. Swierczynska
- Max-Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Department of Internal Medicine III, Carl Gustav Carus Medical School, Technical University of Dresden, Dresden, Germany
| | - Veena Kumari
- Max-Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Monika Ehrhart-Bornstein
- Department of Internal Medicine III, Carl Gustav Carus Medical School, Technical University of Dresden, Dresden, Germany
| | - Stefan R. Bornstein
- Department of Internal Medicine III, Carl Gustav Carus Medical School, Technical University of Dresden, Dresden, Germany
| | - Suzanne Eaton
- Max-Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
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80
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Willnow TE, Christ A, Hammes A. Endocytic receptor-mediated control of morphogen signaling. Development 2013; 139:4311-9. [PMID: 23132241 DOI: 10.1242/dev.084467] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Receptor-mediated endocytosis provides a mechanism by which cells take up signaling molecules from the extracellular space. Recent studies have shown that one class of endocytic receptors, the low-density lipoprotein receptor-related proteins (LRPs), is of particular relevance for embryonic development. In this Primer, we describe how LRPs constitute central pathways that modulate morphogen presentation to target tissues and cellular signal reception, and how LRP dysfunction leads to developmental disturbances in many species.
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Affiliation(s)
- Thomas E Willnow
- Max-Delbrueck-Center for Molecular Medicine, D-13125 Berlin, Germany.
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81
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Riobo NA. Cholesterol and its derivatives in Sonic Hedgehog signaling and cancer. Curr Opin Pharmacol 2012; 12:736-41. [PMID: 22832232 DOI: 10.1016/j.coph.2012.07.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 07/02/2012] [Accepted: 07/03/2012] [Indexed: 10/28/2022]
Abstract
The connection between the Hedgehog (HH) pathway and cholesterol has been recognized since the early days that shaped our current understanding of this unique pathway. Cholesterol and related lipids are intricately linked to HH signaling: from the role of cholesterol in HH biosynthesis to the modulation of HH signal reception and transduction by other sterols, passing by the phylogenetic relationships among many components of the HH pathway that resemble or contain lipid-binding domains. Here I review the connections between HH signaling, cholesterol and its derivatives and analyze the potential implications for HH-dependent cancers.
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Affiliation(s)
- Natalia A Riobo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA, USA.
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82
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Spuch C, Ortolano S, Navarro C. LRP-1 and LRP-2 receptors function in the membrane neuron. Trafficking mechanisms and proteolytic processing in Alzheimer's disease. Front Physiol 2012; 3:269. [PMID: 22934024 PMCID: PMC3429044 DOI: 10.3389/fphys.2012.00269] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 06/26/2012] [Indexed: 11/13/2022] Open
Abstract
Low density lipoprotein receptor-related protein (LRP) belongs to the low-density lipoprotein receptor family, generally recognized as cell surface endocytic receptors, which bind and internalize extracellular ligands for degradation in lysosomes. Neurons require cholesterol to function and keep the membrane rafts stable. Cholesterol uptake into the neuron is carried out by ApoE via LRPs receptors on the cell surface. In neurons the most important are LRP-1 and LRP-2, even it is thought that a causal factor in Alzheimer's disease (AD) is the malfunction of this process which cause impairment intracellular signaling as well as storage and/or release of nutrients and toxic compounds. Both receptors are multifunctional cell surface receptors that are widely expressed in several tissues including neurons and astrocytes. LRPs are constituted by an intracellular (ICD) and extracellular domain (ECD). Through its ECD, LRPs bind at least 40 different ligands ranging from lipoprotein and protease inhibitor complex to growth factors and extracellular matrix proteins. These receptors has also been shown to interact with scaffolding and signaling proteins via its ICD in a phosphorylation-dependent manner and to function as a co-receptor partnering with other cell surface or integral membrane proteins. Thus, LRPs are implicated in two major physiological processes: endocytosis and regulation of signaling pathways, which are both involved in diverse biological roles including lipid metabolism, cell growth processes, degradation of proteases, and tissue invasion. Interestingly, LRPs were also localized in neurons in different stages, suggesting that both receptors could be implicated in signal transduction during embryonic development, neuronal outgrowth or in the pathogenesis of AD.
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Affiliation(s)
- Carlos Spuch
- Department of Pathology and Neuropathology, University Hospital of VigoVigo, Spain
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83
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Singapore signalling: the 2012 hedgehog pathway cocktail. EMBO Rep 2012; 13:580-3. [DOI: 10.1038/embor.2012.79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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84
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Ionita-Laza I, Makarov V, Buxbaum JD. Scan-statistic approach identifies clusters of rare disease variants in LRP2, a gene linked and associated with autism spectrum disorders, in three datasets. Am J Hum Genet 2012; 90:1002-13. [PMID: 22578327 DOI: 10.1016/j.ajhg.2012.04.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2012] [Revised: 02/27/2012] [Accepted: 04/19/2012] [Indexed: 01/20/2023] Open
Abstract
Cluster-detection approaches, commonly used in epidemiology and astronomy, can be applied in the context of genetic sequence data for the identification of genetic regions significantly enriched with rare disease-risk variants (DRVs). Unlike existing association tests for sequence data, the goal of cluster-detection methods is to localize significant disease mutation clusters within a gene or region of interest. Here, we focus on a chromosome 2q replicated linkage region that is associated with autism spectrum disorder (ASD) and that has been sequenced in three independent datasets. We found that variants in one gene, LRP2, residing on 2q are associated with ASD in two datasets (the combined variable-threshold-test p value is 1.2 × 10(-5)). Using a cluster-detection method, we show that in the discovery and replication datasets, variants associated with ASD cluster preponderantly in 25 kb windows (adjusted p values are p(1) = 0.003 and p(2) = 0.002), and the two windows are highly overlapping. Furthermore, for the third dataset, a 25 kb region similar to those in the other two datasets shows significant evidence of enrichment of rare DRVs. The region implicated by all three studies is involved in ligand binding, suggesting that subtle alterations in either LRP2 expression or LRP2 primary sequence modulate the uptake of LRP2 ligands. BMP4 is a ligand of particular interest given its role in forebrain development, and modest changes in BMP4 binding, which binds to LRP2 near the mutation cluster, might subtly affect development and could lead to autism-associated phenotypes.
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