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Fan S, Liu J, Chofflet N, Bailey AO, Russell WK, Zhang Z, Takahashi H, Ren G, Rudenko G. Molecular mechanism of contactin 2 homophilic interaction. Structure 2024:S0969-2126(24)00222-3. [PMID: 38968938 DOI: 10.1016/j.str.2024.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/23/2024] [Accepted: 06/10/2024] [Indexed: 07/07/2024]
Abstract
Contactin 2 (CNTN2) is a cell adhesion molecule involved in axon guidance, neuronal migration, and fasciculation. The ectodomains of CNTN1-CNTN6 are composed of six Ig domains (Ig1-Ig6) and four FN domains. Here, we show that CNTN2 forms transient homophilic interactions (KD ∼200 nM). Cryo-EM structures of full-length CNTN2 and CNTN2_Ig1-Ig6 reveal a T-shaped homodimer formed by intertwined, parallel monomers. Unexpectedly, the horseshoe-shaped Ig1-Ig4 headpieces extend their Ig2-Ig3 tips outwards on either side of the homodimer, while Ig4, Ig5, Ig6, and the FN domains form a central stalk. Cross-linking mass spectrometry and cell-based binding assays confirm the 3D assembly of the CNTN2 homodimer. The interface mediating homodimer formation differs between CNTNs, as do the homophilic versus heterophilic interaction mechanisms. The CNTN family thus encodes a versatile molecular platform that supports a very diverse portfolio of protein interactions and that can be leveraged to strategically guide neural circuit development.
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Affiliation(s)
- Shanghua Fan
- Department of Pharmacology and Toxicology; University of Texas Medical Branch, Galveston, TX 77555, USA; Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Jianfang Liu
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Nicolas Chofflet
- Synapse Development and Plasticity Research Unit, Institut de Recherches Cliniques de Montréal, Montreal, QC H2W 1R7, Canada; Integrated Program in Neuroscience, McGill University, Montreal, QC H3A 2B2, Canada
| | - Aaron O Bailey
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - William K Russell
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Ziqi Zhang
- Synapse Development and Plasticity Research Unit, Institut de Recherches Cliniques de Montréal, Montreal, QC H2W 1R7, Canada
| | - Hideto Takahashi
- Synapse Development and Plasticity Research Unit, Institut de Recherches Cliniques de Montréal, Montreal, QC H2W 1R7, Canada; Department of Medicine, Université de Montréal, Montreal, QC H3T 1J4, Canada; Division of Experimental Medicine, McGill University, Montreal, QC H3A 0G4, Canada.
| | - Gang Ren
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Gabby Rudenko
- Department of Pharmacology and Toxicology; University of Texas Medical Branch, Galveston, TX 77555, USA; Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch, Galveston, TX 77555, USA.
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Stezin A, Sathe GJ, Gajbhiye A, Bharadwaj S, Ghose V, Bellad A, Malo PK, Holla V, Hegde S, Bharath RD, Saini J, Jain S, Yadav R, Pandey A, Pal PK. Dysregulated Cerebrospinal Fluid Proteome of Spinocerebellar Ataxia Type 2 and its Clinical Implications. Mov Disord 2024. [PMID: 38769639 DOI: 10.1002/mds.29834] [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: 12/12/2023] [Revised: 03/07/2024] [Accepted: 04/29/2024] [Indexed: 05/22/2024] Open
Abstract
BACKGROUND Abnormalities in ataxin-2 associated with spinocerebellar ataxia type 2 (SCA2) may lead to widespread disruptions in the proteome. This study was performed to identify dysregulated proteome in SCA2 and to explore its clinical-radiological correlations. METHODS Cerebrospinal fluid (CSF) samples from 21 genetically confirmed SCA2 were subjected to shotgun proteome analysis using mass spectrometry (MS) and tandem mass tag (TMT)-based multiplexing. Proteins with at least 1.5-fold change in abundance were identified. Their relative abundance was measured using parallel reaction monitoring (PRM) and correlated against disease-related factors. RESULTS Eleven proteins were significantly upregulated in SCA2. They belonged to the family of cell adhesion molecules and granins. Their fold changes showed significant clinical, genetic, and radiological correlations. CONCLUSIONS Significant dysregulation of CSF proteome is seen in SCA2. The dysregulated protein may have potential use in clinical evaluation of patients with SCA2. © 2024 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Albert Stezin
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
- Clinical Neurosciences, Centre for Brain Research (CBR), Indian Institute of Science (IISc), Bangalore, India
| | | | | | - Sujas Bharadwaj
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Vivek Ghose
- Institute of Bioinformatics (IOB), Bangalore, India
| | | | - Palash Kumar Malo
- Clinical Neurosciences, Centre for Brain Research (CBR), Indian Institute of Science (IISc), Bangalore, India
| | - Vikram Holla
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Shantala Hegde
- Department of Clinical Psychology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Rose Dawn Bharath
- Department of Neuroimaging and Interventional Neuroimaging, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Jitender Saini
- Department of Neuroimaging and Interventional Neuroimaging, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Sanjeev Jain
- Molecular Genetics Laboratory, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
- Department of Psychiatry, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Ravi Yadav
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
| | - Akhilesh Pandey
- Institute of Bioinformatics (IOB), Bangalore, India
- Center for Individualized Medicine, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Pramod Kumar Pal
- Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Bangalore, India
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Hallada LP, Shirinifard A, Solecki DJ. Junctional Adhesion Molecule (JAM)-C recruitment of Pard3 and drebrin to cell contacts initiates neuron-glia recognition and layer-specific cell sorting in developing cerebella. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.26.586832. [PMID: 38585827 PMCID: PMC10996703 DOI: 10.1101/2024.03.26.586832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Sorting maturing neurons into distinct layers is critical for brain development, with disruptions leading to neurological disorders and pediatric cancers. Lamination coordinates where, when, and how cells interact, facilitating events that direct migrating neurons to their destined positions within emerging neural networks and control the wiring of connections in functional circuits. While the role of adhesion molecule expression and presentation in driving adhesive recognition during neuronal migration along glial fibers is recognized, the mechanisms by which the spatial arrangement of these molecules on the cell surface dictates adhesive specificity and translates contact-based external cues into intracellular responses like polarization and cytoskeletal organization remain largely unexplored. We used the cerebellar granule neuron (CGN) system to demonstrate that JAM-C receptor cis-binding on the same cell and trans-binding to neighboring cells controls the recruitment of the Pard3 polarity protein and drebrin microtubule-actin crosslinker at CGN to glial adhesion sites, complementing previous studies that showed Pard3 controls JAM-C exocytic surface presentation. Leveraging advanced imaging techniques, specific probes for cell recognition, and analytical methods to dissect adhesion dynamics, our findings reveal: 1) JAM-C cis or trans mutants result in reduced adhesion formation between CGNs and cerebellar glia, 2) these mutants exhibit delayed recruitment of Pard3 at the adhesion sites, and 3) CGNs with JAM-C mutations experience postponed sorting and entry into the cerebellar molecular layer (ML). By developing a conditional system to image adhesion components from two different cells simultaneously, we made it possible to investigate the dynamics of cell recognition on both sides of neuron-glial contacts and the subsequent recruitment of proteins required for CGN migration. This system and an approach that calculates local correlation based on convolution kernels at the cell adhesions site revealed that CGN to CGN JAM recognition preferentially recruits higher levels of Pard3 and drebrin than CGN to glia JAM recognition. The long latency time of CGNs in the inner external germinal layer (EGL) can be attributed to the combined strength of CGN-CGN contacts and the less efficient Pard3 recruitment by CGN-BG contacts, acting as gatekeepers to ML entry. As CGNs eventually transition to glia binding for radial migration, our research demonstrates that establishing permissive JAM-recognition sites on glia via cis and trans interactions of CGN JAM-C serves as a critical temporal checkpoint for sorting at the EGL to ML boundary. This mechanism integrates intrinsic and extrinsic cellular signals, facilitating heterotypic cell sorting into the ML and dictating the precise spatial organization within the cerebellar architecture.
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Komatsuya K, Kikuchi N, Hirabayashi T, Kasahara K. The Regulatory Roles of Cerebellar Glycosphingolipid Microdomains/Lipid Rafts. Int J Mol Sci 2023; 24:ijms24065566. [PMID: 36982638 PMCID: PMC10058044 DOI: 10.3390/ijms24065566] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/17/2023] Open
Abstract
Lipid rafts are dynamic assemblies of glycosphingolipids, sphingomyelin, cholesterol, and specific proteins which are stabilized into platforms involved in the regulation of vital cellular processes. Cerebellar lipid rafts are cell surface ganglioside microdomains for the attachment of GPI-anchored neural adhesion molecules and downstream signaling molecules such as Src-family kinases and heterotrimeric G proteins. In this review, we summarize our recent findings on signaling in ganglioside GD3 rafts of cerebellar granule cells and several findings by other groups on the roles of lipid rafts in the cerebellum. TAG-1, of the contactin group of immunoglobulin superfamily cell adhesion molecules, is a phosphacan receptor. Phosphacan regulates the radial migration signaling of cerebellar granule cells, via Src-family kinase Lyn, by binding to TAG-1 on ganglioside GD3 rafts. Chemokine SDF-1α, which induces the tangential migration of cerebellar granule cells, causes heterotrimeric G protein Goα translocation to GD3 rafts. Furthermore, the functional roles of cerebellar raft-binding proteins including cell adhesion molecule L1, heterotrimeric G protein Gsα, and L-type voltage-dependent calcium channels are discussed.
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5
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Dauar MT, Labonté A, Picard C, Miron J, Rosa-Neto P, Zetterberg H, Blennow K, Villeneuve S, Poirier J. Characterization of the contactin 5 protein and its risk-associated polymorphic variant throughout the Alzheimer's disease spectrum. Alzheimers Dement 2022. [PMID: 36583624 DOI: 10.1002/alz.12868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 10/04/2022] [Accepted: 10/17/2022] [Indexed: 12/31/2022]
Abstract
INTRODUCTION We investigate the CNTN5 rs1461684 G variant and the contactin 5 protein in sporadic Alzheimer's disease (sAD). METHODS Contactin 5, sAD biomarkers, and synaptic markers were measured in the cerebrospinal fluid (CSF). Amyloid and tau deposition were assessed using positron emission tomography. Contactin 5 protein and mRNA levels were measured in brain tissue. RESULTS CSF contactin 5 increases progressively in cognitively unimpaired individuals and is decreased in mild cognitive impairment and sAD. CSF contactin 5 correlates with sAD biomarkers and with synaptic markers. The rs1461684 G variant associates with faster disease progression in cognitively unimpaired subjects. Cortical full-length and isoform 3 CNTN5 mRNAs are decreased in the presence of the G allele and as a function of Consortium to Establish a Registry for Alzheimer's Disease stages. DISCUSSION The newly identified rs1461684 G variant associates with sAD risk, rate of disease progression, and gene expression. Contactin 5 protein and mRNA are affected particularly in the early stages of the disease.
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Affiliation(s)
- Marina Tedeschi Dauar
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada.,McGill University, Montréal, Canada.,CAPES Foundation, Ministry of Education of Brazil, Brasília, Brazil
| | - Anne Labonté
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada
| | - Cynthia Picard
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada
| | - Justin Miron
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada.,McGill University, Montréal, Canada
| | - Pedro Rosa-Neto
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada.,McGill University, Montréal, Canada.,Department of Psychiatry, McGill University, Montréal, Canada
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.,UK Dementia Research Institute at UCL, London, UK.,Hong Kong Center for Neurodegenerative Diseases, Hong Kong, China
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Sylvia Villeneuve
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada.,McGill University, Montréal, Canada.,Department of Psychiatry, McGill University, Montréal, Canada
| | - Judes Poirier
- Douglas Mental Health University Institute, Montréal, Canada.,Centre for the Studies in the Prevention of Alzheimer's, Douglas Mental Health University Institute, Montréal, Canada.,McGill University, Montréal, Canada.,Department of Psychiatry, McGill University, Montréal, Canada
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Bizzoca A, Jirillo E, Flace P, Gennarini G. Overall Role of Contactins Expression in Neurodevelopmental Events and Contribution to Neurological Disorders. CNS & NEUROLOGICAL DISORDERS DRUG TARGETS 2022; 22:CNSNDDT-EPUB-128217. [PMID: 36515028 DOI: 10.2174/1871527322666221212160048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 10/21/2022] [Accepted: 10/28/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND Neurodegenerative disorders may depend upon a misregulation of the pathways which sustain neurodevelopmental control. In this context, this review article focuses on Friedreich ataxia (FA), a neurodegenerative disorder resulting from mutations within the gene encoding the Frataxin protein, which is involved in the control of mitochondrial function and oxidative metabolism. OBJECTIVE The specific aim of the present study concerns the FA molecular and cellular substrates, for which available transgenic mice models are proposed, including mutants undergoing misexpression of adhesive/morphoregulatory proteins, in particular belonging to the Contactin subset of the immunoglobulin supergene family. METHODS In both mutant and control mice, neurogenesis was explored by morphological/morphometric analysis through the expression of cell type-specific markers, including -tubulin, the Contactin-1 axonal adhesive glycoprotein, as well as the Glial Fibrillary Acidic Protein (GFAP). RESULTS Specific consequences were found to arise from the chosen misexpression approach, consisting of a neuronal developmental delay associated with glial upregulation. Protective effects against the arising phenotype resulted from antioxidants (essentially epigallocatechin gallate (EGCG)) administration, which was demonstrated through the profiles of neuronal (-tubulin and Contactin 1) as well as glial (GFAP) markers, in turn indicating the concomitant activation of neurodegeneration and neuro repair processes. The latter also implied activation of the Notch-1 signaling. CONCLUSION Overall, this study supports the significance of changes in morphoregulatory proteins expression in the FA pathogenesis and of antioxidant administration in counteracting it, which, in turn, allows to devise potential therapeutic approaches.
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Affiliation(s)
- Antonella Bizzoca
- Department of Basic Medical Sciences, Neurosciences, and Sensory Organs. Medical School. University of Bari. Piazza Giulio Cesare, 11. I-70124 Bari. Italy
| | - Emilio Jirillo
- Department of Basic Medical Sciences, Neurosciences, and Sensory Organs. Medical School. University of Bari. Piazza Giulio Cesare, 11. I-70124 Bari. Italy
| | - Paolo Flace
- Department of Basic Medical Sciences, Neurosciences, and Sensory Organs. Medical School. University of Bari. Piazza Giulio Cesare, 11. I-70124 Bari. Italy
| | - Gianfranco Gennarini
- Department of Basic Medical Sciences, Neurosciences, and Sensory Organs. Medical School. University of Bari. Piazza Giulio Cesare, 11. I-70124 Bari. Italy
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Baeriswyl T, Schaettin M, Leoni S, Dumoulin A, Stoeckli ET. Endoglycan Regulates Purkinje Cell Migration by Balancing Cell-Cell Adhesion. Front Neurosci 2022; 16:894962. [PMID: 35794952 PMCID: PMC9251411 DOI: 10.3389/fnins.2022.894962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
The importance of cell adhesion molecules for the development of the nervous system has been recognized many decades ago. Functional in vitro and in vivo studies demonstrated a role of cell adhesion molecules in cell migration, axon growth and guidance, as well as synaptogenesis. Clearly, cell adhesion molecules have to be more than static glue making cells stick together. During axon guidance, cell adhesion molecules have been shown to act as pathway selectors but also as a means to prevent axons going astray by bundling or fasciculating axons. We identified Endoglycan as a negative regulator of cell-cell adhesion during commissural axon guidance across the midline. The presence of Endoglycan allowed commissural growth cones to smoothly navigate the floor-plate area. In the absence of Endoglycan, axons failed to exit the floor plate and turn rostrally. These observations are in line with the idea of Endoglycan acting as a lubricant, as its presence was important, but it did not matter whether Endoglycan was provided by the growth cone or the floor-plate cells. Here, we expand on these observations by demonstrating a role of Endoglycan during cell migration. In the developing cerebellum, Endoglycan was expressed by Purkinje cells during their migration from the ventricular zone to the periphery. In the absence of Endoglycan, Purkinje cells failed to migrate and, as a consequence, cerebellar morphology was strongly affected. Cerebellar folds failed to form and grow, consistent with earlier observations on a role of Purkinje cells as Shh deliverers to trigger granule cell proliferation.
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Cervantes González A, Belbin O. Fluid markers of synapse degeneration in synucleinopathies. J Neural Transm (Vienna) 2022; 129:187-206. [PMID: 35147800 DOI: 10.1007/s00702-022-02467-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 01/20/2022] [Indexed: 01/06/2023]
Abstract
The abnormal accumulation of α-synuclein in the brain is a common feature of Parkinson's disease (PD), PD dementia (PDD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), and synucleinopathies that present with overlapping but distinct clinical symptoms that include motor and cognitive deficits. Synapse degeneration is the crucial neuropathological event in these synucleinopathies and the neuropathological correlate of connectome dysfunction. The cognitive and motor deficits resulting from the connectome dysfunction are currently measured by scalar systems that are limited in their sensitivity and largely subjective. Ideally, a marker of synapse degeneration would correlate with measures of cognitive or motor impairment, and could therefore be used as a more objective, surrogate biomarker of the core clinical features of these diseases. Furthermore, an objective surrogate biomarker that can detect and monitor the progression of synapse degeneration would improve patient management and clinical trial design, and could provide a measure of therapeutic response. Here, we review the published findings relating to candidate biomarkers of synapse degeneration in PD, PDD, DLB, and MSA patient-derived biofluids and discuss the findings in the context of the mechanisms associated with α-synuclein-mediated synapse degeneration. Understanding these mechanisms is essential not only for discovery of biomarkers, but also to improve our understanding of the earliest changes in disease pathogenesis of synucleinopathies.
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Affiliation(s)
- Alba Cervantes González
- Neurology Department, Biomedical Research Institute Sant Pau (IIB Sant Pau) and Sant Pau Memory Unit, Hospital de la Santa Creu i Sant Pau, 08025, Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain
| | - Olivia Belbin
- Neurology Department, Biomedical Research Institute Sant Pau (IIB Sant Pau) and Sant Pau Memory Unit, Hospital de la Santa Creu i Sant Pau, 08025, Barcelona, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), 28031, Madrid, Spain.
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9
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Shabanipour S, Jiao X, Rahimi-Balaei M, Aghanoori MR, Chung SH, Ghavami S, Consalez GG, Marzban H. Upregulation of Neural Cell Adhesion Molecule 1 and Excessive Migration of Purkinje Cells in Cerebellar Cortex. Front Neurosci 2022; 15:804402. [PMID: 35126044 PMCID: PMC8814629 DOI: 10.3389/fnins.2021.804402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
Purkinje cells (PCs) are large GABAergic projection neurons of the cerebellar cortex, endowed with elaborate dendrites that receive a multitude of excitatory inputs. Being the only efferent neuron of the cerebellar cortex, PCs project to cerebellar nuclei and control behaviors ranging from movement to cognition and social interaction. Neural cell adhesion molecule 1 (NCAM1) is widely expressed in the embryonic and postnatal development of the brain and plays essential roles in neuronal migration, axon pathfinding and synapse assembly. However, despite its high expression levels in cerebellum, little is known to date regarding the role(s) of NCAM1 in PCs development. Among other aspects, elucidating how the expression of NCAM1 in PCs could impact their postnatal migration would be a significant achievement. We analyzed the Acp2 mutant mouse (nax: naked and ataxia), which displays excessive PC migration into the molecular layer, and investigated how the excessive migration of PCs along Bergmann glia could correlate to NCAM1 expression pattern in early postnatal days. Our Western blot and RT-qPCR analysis of the whole cerebellum show that the protein and mRNA of NCAM1 in wild type are not different during PC dispersal from the cluster stage to monolayer formation. However, RT-qPCR analysis from FACS-based isolated PCs shows that Ncam1 is significantly upregulated when PCs fail to align and instead overmigrate into the molecular layer. Our results suggest two alternative interpretations: (1) NCAM1 promotes excessive PC migration along Bergmann glia, or (2) NCAM1 upregulation is an attempt to prevent PCs from invading the molecular layer. If the latter scenario proves true, NCAM1 may play a key role in PC monolayer formation.
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Affiliation(s)
- Shahin Shabanipour
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Xiaodan Jiao
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Maryam Rahimi-Balaei
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Mohamad Reza Aghanoori
- Department of Pharmacology and Therapeutics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Seung H. Chung
- Department of Oral Biology, University of Illinois Chicago, Chicago, IL, United States
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - G. Giacomo Consalez
- Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Hassan Marzban
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- The Children’s Hospital Research Institute of Manitoba (CHRIM), Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- *Correspondence: Hassan Marzban,
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10
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Dunn HA, Orlandi C, Martemyanov KA. Beyond the Ligand: Extracellular and Transcellular G Protein-Coupled Receptor Complexes in Physiology and Pharmacology. Pharmacol Rev 2019; 71:503-519. [PMID: 31515243 DOI: 10.1124/pr.119.018044] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
G protein-coupled receptors (GPCRs) remain one of the most successful targets of U.S. Food and Drug Administration-approved drugs. GPCR research has predominantly focused on the characterization of the intracellular interactome's contribution to GPCR function and pharmacology. However, emerging evidence uncovers a new dimension in the biology of GPCRs involving their extracellular and transcellular interactions that critically impact GPCR function and pharmacology. The seminal examples include a variety of adhesion GPCRs, such as ADGRLs/latrophilins, ADGRBs/brain angiogenesis inhibitors, ADGRG1/GPR56, ADGRG6/GPR126, ADGRE5/CD97, and ADGRC3/CELSR3. However, recent advances have indicated that class C GPCRs that contain large extracellular domains, including group III metabotropic glutamate receptors (mGluR4, mGluR6, mGluR7, mGluR8), γ-aminobutyric acid receptors, and orphans GPR158 and GPR179, can also participate in this form of transcellular regulation. In this review, we will focus on a variety of identified extracellular and transcellular GPCR-interacting partners, including teneurins, neurexins, integrins, fibronectin leucine-rich transmembranes, contactin-6, neuroligin, laminins, collagens, major prion protein, amyloid precursor protein, complement C1q-likes, stabilin-2, pikachurin, dystroglycan, complement decay-accelerating factor CD55, cluster of differentiation CD36 and CD90, extracellular leucine-rich repeat and fibronectin type III domain containing 1, and leucine-rich repeat, immunoglobulin-like domain and transmembrane domains. We provide an account on the diversity of extracellular and transcellular GPCR complexes and their contribution to key cellular and physiologic processes, including cell migration, axon guidance, cellular and synaptic adhesion, and synaptogenesis. Furthermore, we discuss models and mechanisms by which extracellular GPCR assemblies may regulate communication at cellular junctions. SIGNIFICANCE STATEMENT: G protein-coupled receptors (GPCRs) continue to be the prominent focus of pharmacological intervention for a variety of human pathologies. Although the majority of GPCR research has focused on the intracellular interactome, recent advancements have identified an extracellular dimension of GPCR modulation that alters accepted pharmacological principles of GPCRs. Herein, we describe known endogenous allosteric modulators acting on GPCRs both in cis and in trans.
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Affiliation(s)
- Henry A Dunn
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida
| | - Cesare Orlandi
- Department of Neuroscience, The Scripps Research Institute, Jupiter, Florida
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Liang S, Liang S, Yin N, Hu B, Faiola F. Toxicogenomic analyses of the effects of BDE-47/209, TBBPA/S and TCBPA on early neural development with a human embryonic stem cell in vitro differentiation system. Toxicol Appl Pharmacol 2019; 379:114685. [DOI: 10.1016/j.taap.2019.114685] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/20/2019] [Accepted: 07/16/2019] [Indexed: 01/02/2023]
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12
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Picocci S, Bizzoca A, Corsi P, Magrone T, Jirillo E, Gennarini G. Modulation of Nerve Cell Differentiation: Role of Polyphenols and of Contactin Family Components. Front Cell Dev Biol 2019; 7:119. [PMID: 31380366 PMCID: PMC6656924 DOI: 10.3389/fcell.2019.00119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/12/2019] [Indexed: 12/18/2022] Open
Abstract
In this study the mechanisms are explored, which modulate expression and function of cell surface adhesive glycoproteins of the Immunoglobulin Supergene Family (IgSF), and in particular of its Contactin subset, during neuronal precursor developmental events. In this context, a specific topic concerns the significance of the expression profile of such molecules and their ability to modulate signaling pathways activated through nutraceuticals, in particular polyphenols, administration. Both in vitro and in vivo approaches are chosen. As for the former, by using as a model the human SH-SY5Y neuroblastoma line, the effects of grape seed polyphenols are evaluated on proliferation and commitment/differentiation events along the neuronal lineage. In SH-SY5Y cell cultures, polyphenols were found to counteract precursor proliferation while promoting their differentiation, as deduced by studying their developmental parameters through the expression of cell cycle and neuronal commitment/differentiation markers as well as by measuring neurite growth. In such cultures, Cyclin E expression and BrdU incorporation were downregulated, indicating reduced precursor proliferation while increased neuronal differentiation was inferred from upregulation of cell cycle exit (p27–Kip) and neuronal commitment (NeuN) markers as well as by measuring neurite length through morphometric analysis. The polyphenol effects on developmental parameters were also explored in vivo, in cerebellar cortex, by using as a model the TAG/F3 transgenic line, which undergoes delayed neural development as a consequence of Contactin1 adhesive glycoprotein upregulation and premature expression under control of the Contactin2 gene (Cntn-2) promoter. In this transgenic line, a Notch pathway activation is known to occur and polyphenol treatment was found to counteract such an effect, demonstrated through downregulation of the Hes-1 transcription factor. Polyphenols also downregulated the expression of adhesive glycoproteins of the Contactin family themselves, demonstrated for both Contactin1 and Contactin2, indicating the involvement of changes in the expression of the underlying genes in the observed phenotype. These data support the hypothesis that the complex control exerted by polyphenols on neural development involves modulation of expression and function of the genes encoding cell adhesion molecules of the Contactin family and of the associated signaling pathways, indicating potential mechanisms whereby such compounds may control neurogenesis.
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Affiliation(s)
- Sabrina Picocci
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Antonella Bizzoca
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Patrizia Corsi
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Thea Magrone
- Laboratories of Immunology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Emilio Jirillo
- Laboratories of Immunology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
| | - Gianfranco Gennarini
- Laboratories of Developmental Neurobiology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Aldo Moro, Bari, Italy
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13
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Castagna C, Merighi A, Lossi L. Decreased Expression of Synaptophysin 1 (SYP1 Major Synaptic Vesicle Protein p38) and Contactin 6 (CNTN6/NB3) in the Cerebellar Vermis of reln Haplodeficient Mice. Cell Mol Neurobiol 2019; 39:833-856. [PMID: 31098770 DOI: 10.1007/s10571-019-00683-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 05/02/2019] [Indexed: 01/17/2023]
Abstract
Reeler heterozygous mice (reln+/-) are seemingly normal but haplodeficient in reln, a gene implicated in autism. Structural/neurochemical alterations in the reln+/- brain are subtle and difficult to demonstrate. Therefore, the usefulness of these mice in translational research is still debated. As evidence implicated several synapse-related genes in autism and the cerebellar vermis is structurally altered in the condition, we have investigated the expression of synaptophysin 1 (SYP1) and contactin 6 (CNTN6) within the vermis of reln+/- mice. Semi-thin plastic sections of the vermis from adult mice of both sexes and different genotypes (reln+/- and reln+/+) were processed with an indirect immunofluorescence protocol. Immunofluorescence was quantified on binary images and statistically analyzed. Reln+/- males displayed a statistically significant reduction of 11.89% in the expression of SYP1 compared to sex-matched wild-type animals, whereas no differences were observed between reln+/+ and reln+/- females. In reln+/- male mice, reductions were particularly evident in the molecular layer: 10.23% less SYP1 than reln+/+ males and 5.84% < reln+/+ females. In reln+/- females, decrease was 9.84% versus reln+/+ males and 5.43% versus reln+/+ females. Both reln+/- males and females showed a stronger decrease in CNTN6 expression throughout all the three cortical layers of the vermis: 17-23% in the granular layer, 24-26% in the Purkinje cell layer, and 9-14% in the molecular layer. Altogether, decrease of vermian SYP1 and CNTN6 in reln+/- mice displayed patterns compatible with the structural modifications of the autistic cerebellum. Therefore, these mice may be a good model in translational studies.
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Affiliation(s)
- Claudia Castagna
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Turin, Grugliasco (TO), Italy.
| | - Adalberto Merighi
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Turin, Grugliasco (TO), Italy
| | - Laura Lossi
- Department of Veterinary Sciences, University of Turin, Largo Paolo Braccini 2, I-10095, Turin, Grugliasco (TO), Italy
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14
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Chatterjee M, Schild D, Teunissen CE. Contactins in the central nervous system: role in health and disease. Neural Regen Res 2019; 14:206-216. [PMID: 30530999 PMCID: PMC6301169 DOI: 10.4103/1673-5374.244776] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 09/17/2018] [Indexed: 01/06/2023] Open
Abstract
Contactins are a group of cell adhesion molecules that are mainly expressed in the brain and play pivotal roles in the organization of axonal domains, axonal guidance, neuritogenesis, neuronal development, synapse formation and plasticity, axo-glia interactions and neural regeneration. Contactins comprise a family of six members. Their absence leads to malformed axons and impaired nerve conduction. Contactin mediated protein complex formation is critical for the organization of the axon in early central nervous system development. Mutations and differential expression of contactins have been identified in neuro-developmental or neurological disorders. Taken together, contactins are extensively studied in the context of nervous system development. This review summarizes the physiological roles of all six members of the Contactin family in neurodevelopment as well as their involvement in neurological/neurodevelopmental disorders.
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Affiliation(s)
- Madhurima Chatterjee
- Amsterdam UMC, VU University Medical Center, Department of Clinical Chemistry, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Detlev Schild
- Institute of Neurophysiology and Cellular Biophysics, University of Göttingen, Göttingen, Germany
- DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB), University of Göttingen, Göttingen, Germany
- DFG Excellence Cluster 171, University of Göttingen, Göttingen, Germany
| | - Charlotte E. Teunissen
- Amsterdam UMC, VU University Medical Center, Department of Clinical Chemistry, Amsterdam Neuroscience, Amsterdam, The Netherlands
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15
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Medina-Cano D, Ucuncu E, Nguyen LS, Nicouleau M, Lipecka J, Bizot JC, Thiel C, Foulquier F, Lefort N, Faivre-Sarrailh C, Colleaux L, Guerrera IC, Cantagrel V. High N-glycan multiplicity is critical for neuronal adhesion and sensitizes the developing cerebellum to N-glycosylation defect. eLife 2018; 7:38309. [PMID: 30311906 PMCID: PMC6185108 DOI: 10.7554/elife.38309] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 10/01/2018] [Indexed: 12/14/2022] Open
Abstract
Proper brain development relies highly on protein N-glycosylation to sustain neuronal migration, axon guidance and synaptic physiology. Impairing the N-glycosylation pathway at early steps produces broad neurological symptoms identified in congenital disorders of glycosylation. However, little is known about the molecular mechanisms underlying these defects. We generated a cerebellum specific knockout mouse for Srd5a3, a gene involved in the initiation of N-glycosylation. In addition to motor coordination defects and abnormal granule cell development, Srd5a3 deletion causes mild N-glycosylation impairment without significantly altering ER homeostasis. Using proteomic approaches, we identified that Srd5a3 loss affects a subset of glycoproteins with high N-glycans multiplicity per protein and decreased protein abundance or N-glycosylation level. As IgSF-CAM adhesion proteins are critical for neuron adhesion and highly N-glycosylated, we observed impaired IgSF-CAM-mediated neurite outgrowth and axon guidance in Srd5a3 mutant cerebellum. Our results link high N-glycan multiplicity to fine-tuned neural cell adhesion during mammalian brain development.
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Affiliation(s)
- Daniel Medina-Cano
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Ekin Ucuncu
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Lam Son Nguyen
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Michael Nicouleau
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Joanna Lipecka
- Proteomics platform 3P5-Necker, Université Paris Descartes - Structure Fédérative de Recherche Necker, INSERM US24/CNRS UMS3633, Paris, France
| | | | - Christian Thiel
- Center for Child and Adolescent Medicine, Kinderheilkunde I, University of Heidelberg, Heidelberg, Germany
| | - François Foulquier
- Université Lille, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, CNRS, Lille, France
| | | | | | - Laurence Colleaux
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
| | - Ida Chiara Guerrera
- Proteomics platform 3P5-Necker, Université Paris Descartes - Structure Fédérative de Recherche Necker, INSERM US24/CNRS UMS3633, Paris, France
| | - Vincent Cantagrel
- Paris Descartes-Sorbonne Paris Cité University, Paris, France.,Developmental Brain Disorders Laboratory, Imagine Institute, INSERM UMR 1163, Paris, France
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16
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Contactin-2, a synaptic and axonal protein, is reduced in cerebrospinal fluid and brain tissue in Alzheimer's disease. ALZHEIMERS RESEARCH & THERAPY 2018; 10:52. [PMID: 29859129 PMCID: PMC5984818 DOI: 10.1186/s13195-018-0383-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/09/2018] [Indexed: 11/23/2022]
Abstract
Background Synaptic and axonal loss are two major mechanisms underlying Alzheimer’s disease (AD) pathogenesis, and biomarkers reflecting changes in these cellular processes are needed for early diagnosis and monitoring the progression of AD. Contactin-2 is a synaptic and axonal membrane protein that interacts with proteins involved in the pathology of AD such as amyloid precursor protein (APP) and beta-secretase 1 (BACE1). We hypothesized that AD might be characterized by changes in contactin-2 levels in the cerebrospinal fluid (CSF) and brain tissue. Therefore, we aimed to investigate the levels of contactin-2 in the CSF and evaluate its relationship with disease pathology. Methods Contactin-2 was measured in CSF from two cohorts (selected from the Amsterdam Dementia Cohort), comprising samples from controls (cohort 1, n = 28; cohort 2, n = 20) and AD (cohort 1, n = 36; cohort 2, n = 70) using an analytically validated commercial enzyme-linked immunosorbent assay (ELISA). The relationship of contactin-2 with cognitive decline (Mini-Mental State Examination (MMSE)) and other CSF biomarkers reflecting AD pathology were analyzed. We further characterized the expression of contactin-2 in postmortem AD human brain (n = 14) versus nondemented controls (n = 9). Results CSF contactin-2 was approximately 1.3-fold reduced in AD patients compared with controls (p < 0.0001). Overall, contactin-2 levels correlated with MMSE scores (r = 0.35, p = 0.004). We observed that CSF contactin-2 correlated with the levels of phosphorylated tau within the control (r = 0.46, p < 0.05) and AD groups (r = 0.31, p < 0.05). Contactin-2 also correlated strongly with another synaptic biomarker, neurogranin (control: r = 0.62, p < 0.05; AD: r = 0.60, p < 0.01), and BACE1, a contactin-2 processing enzyme (control: r = 0.64, p < 0.01; AD: r = 0.46, p < 0.05). Results were further validated in a second cohort (p < 0.01). Immunohistochemical analysis revealed that contactin-2 is expressed in the extracellular matrix. Lower levels of contactin-2 were specifically found in and around amyloid plaques in AD hippocampus and temporal cortex. Conclusions Taken together, these data reveal that the contactin-2 changes observed in tissues are reflected in CSF, suggesting that decreased contactin-2 CSF levels might be a biomarker reflecting synaptic or axonal loss. Electronic supplementary material The online version of this article (10.1186/s13195-018-0383-x) contains supplementary material, which is available to authorized users.
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17
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Smirnov AV, Kontsevaya GV, Feofanova NA, Anisimova MV, Serova IA, Gerlinskaya LA, Battulin NR, Moshkin MP, Serov OL. Unexpected phenotypic effects of a transgene integration causing a knockout of the endogenous Contactin-5 gene in mice. Transgenic Res 2017; 27:1-13. [PMID: 29264679 DOI: 10.1007/s11248-017-0053-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/01/2017] [Indexed: 01/06/2023]
Abstract
Contactins (Cntn1-6) are a family of neuronal membrane proteins expressed in the brain. They are required for establishing cell-to-cell contacts between neurons and for the growth and maturation of the axons. In humans, structural genomic variations in the Contactin genes are implicated in neurodevelopmental disorders. In addition, population genetic studies associate Contactins loci with obesity and hypertension. Cntn5 knockout mice were first described in 2003, but showed no gross physiological or behavioral abnormalities (just minor auditory defects). We report a novel Cntn5 knockout mouse line generated by a random transgene integration as an outcome of pronuclear microinjection. Investigation of the transgene integration site revealed that the 6Kbp transgene construct coding for the human granulocyte-macrophage colony-stimulating factor (hGMCSF) replaced 170 Kbp of the Cntn5 gene, including four exons. Reverse transcription PCR analysis of the Cntn5 transcripts in the wild-type and transgenic mouse lines showed that splicing of the transgene leads to a set of chimeric hGMCSF-Cntn5 transcript variants, none of which encode functional Cntn5 protein due to introduction of stop codons. Although Cntn5 knockout animals displayed no abnormalities in behavior, we noted that they were leaner, with less body mass and fat percentage than wild-type animals. Their cardiovascular parameters (heart rate, blood pressure and blood flow speed) were elevated compared to controls. These findings link Cntn5 deficiency to obesity and hypertension.
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Affiliation(s)
- Alexander V Smirnov
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia.
| | - Galina V Kontsevaya
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Natalia A Feofanova
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Margarita V Anisimova
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Irina A Serova
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Lyudmila A Gerlinskaya
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Nariman R Battulin
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia
| | - Mikhail P Moshkin
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Oleg L Serov
- Federal Research Center Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia. .,Novosibirsk State University, Novosibirsk, Russia.
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18
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Neural Glycosylphosphatidylinositol-Anchored Proteins in Synaptic Specification. Trends Cell Biol 2017; 27:931-945. [PMID: 28743494 DOI: 10.1016/j.tcb.2017.06.007] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Revised: 06/27/2017] [Accepted: 06/29/2017] [Indexed: 12/15/2022]
Abstract
Glycosylphosphatidylinositol (GPI)-anchored proteins are a specialized class of lipid-associated neuronal membrane proteins that perform diverse functions in the dynamic control of axon guidance, synaptic adhesion, cytoskeletal remodeling, and localized signal transduction, particularly at lipid raft domains. Recent studies have demonstrated that a subset of GPI-anchored proteins act as critical regulators of synapse development by modulating specific synaptic adhesion pathways via direct interactions with key synapse-organizing proteins. Additional studies have revealed that alteration of these regulatory mechanisms may underlie various brain disorders. In this review, we highlight the emerging role of GPI-anchored proteins as key synapse organizers that aid in shaping the properties of various types of synapses and circuits in mammals.
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19
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Takeuchi M, Inoue C, Goshima A, Nagao Y, Shimizu K, Miyamoto H, Shimizu T, Hashimoto H, Yonemura S, Kawahara A, Hirata Y, Yoshida M, Hibi M. Medaka and zebrafishcontactin1mutants as a model for understanding neural circuits for motor coordination. Genes Cells 2017. [DOI: 10.1111/gtc.12509] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Miki Takeuchi
- Laboratory of Organogenesis and Organ Function; Bioscience and Biotechnology Center; Nagoya University; Furo Chikusa Nagoya Aichi 464-8601 Japan
| | - Chikako Inoue
- Laboratory of Organogenesis and Organ Function; Bioscience and Biotechnology Center; Nagoya University; Furo Chikusa Nagoya Aichi 464-8601 Japan
| | - Akiko Goshima
- Division of Biological Science; Graduate School of Science; Nagoya University; Furo Chikusa Nagoya Aichi 464-8602 Japan
| | - Yusuke Nagao
- Laboratory of Organogenesis and Organ Function; Bioscience and Biotechnology Center; Nagoya University; Furo Chikusa Nagoya Aichi 464-8601 Japan
| | - Koichi Shimizu
- Division of Biological Science; Graduate School of Science; Nagoya University; Furo Chikusa Nagoya Aichi 464-8602 Japan
| | - Hiroki Miyamoto
- Department of Computer Science; Chubu University; 1200 Matsumoto Kasugai Aichi 485-8501 Japan
| | - Takashi Shimizu
- Laboratory of Organogenesis and Organ Function; Bioscience and Biotechnology Center; Nagoya University; Furo Chikusa Nagoya Aichi 464-8601 Japan
- Division of Biological Science; Graduate School of Science; Nagoya University; Furo Chikusa Nagoya Aichi 464-8602 Japan
| | - Hisashi Hashimoto
- Laboratory of Organogenesis and Organ Function; Bioscience and Biotechnology Center; Nagoya University; Furo Chikusa Nagoya Aichi 464-8601 Japan
- Division of Biological Science; Graduate School of Science; Nagoya University; Furo Chikusa Nagoya Aichi 464-8602 Japan
| | - Shigenobu Yonemura
- Department of Cell Biology; Graduate School of Medical Science; Tokushima University; 3-18-15 Kuramoto Tokushima Tokushima 770-8503 Japan
| | - Atsuo Kawahara
- Laboratory for Developmental Biology; Center for Medical Education and Sciences; Graduate School of Medical Science; University of Yamanashi; 1110 Shimokato, Chuo; Yamanashi 409-3898 Japan
| | - Yutaka Hirata
- Department of Computer Science; Chubu University; 1200 Matsumoto Kasugai Aichi 485-8501 Japan
| | - Masayuki Yoshida
- Graduate School of Biosphere Sciences; Hiroshima University; 1-4-4 Kagamiyama Higashihiroshima Hiroshima 739-8528 Japan
| | - Masahiko Hibi
- Laboratory of Organogenesis and Organ Function; Bioscience and Biotechnology Center; Nagoya University; Furo Chikusa Nagoya Aichi 464-8601 Japan
- Division of Biological Science; Graduate School of Science; Nagoya University; Furo Chikusa Nagoya Aichi 464-8602 Japan
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20
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Mercati O, Huguet G, Danckaert A, André-Leroux G, Maruani A, Bellinzoni M, Rolland T, Gouder L, Mathieu A, Buratti J, Amsellem F, Benabou M, Van-Gils J, Beggiato A, Konyukh M, Bourgeois JP, Gazzellone MJ, Yuen RKC, Walker S, Delépine M, Boland A, Régnault B, Francois M, Van Den Abbeele T, Mosca-Boidron AL, Faivre L, Shimoda Y, Watanabe K, Bonneau D, Rastam M, Leboyer M, Scherer SW, Gillberg C, Delorme R, Cloëz-Tayarani I, Bourgeron T. CNTN6 mutations are risk factors for abnormal auditory sensory perception in autism spectrum disorders. Mol Psychiatry 2017; 22:625-633. [PMID: 27166760 PMCID: PMC5378808 DOI: 10.1038/mp.2016.61] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 02/12/2016] [Accepted: 02/17/2016] [Indexed: 12/11/2022]
Abstract
Contactin genes CNTN5 and CNTN6 code for neuronal cell adhesion molecules that promote neurite outgrowth in sensory-motor neuronal pathways. Mutations of CNTN5 and CNTN6 have previously been reported in individuals with autism spectrum disorders (ASDs), but very little is known on their prevalence and clinical impact. In this study, we identified CNTN5 and CNTN6 deleterious variants in individuals with ASD. Among the carriers, a girl with ASD and attention-deficit/hyperactivity disorder was carrying five copies of CNTN5. For CNTN6, both deletions (6/1534 ASD vs 1/8936 controls; P=0.00006) and private coding sequence variants (18/501 ASD vs 535/33480 controls; P=0.0005) were enriched in individuals with ASD. Among the rare CNTN6 variants, two deletions were transmitted by fathers diagnosed with ASD, one stop mutation CNTN6W923X was transmitted by a mother to her two sons with ASD and one variant CNTN6P770L was found de novo in a boy with ASD. Clinical investigations of the patients carrying CNTN5 or CNTN6 variants showed that they were hypersensitive to sounds (a condition called hyperacusis) and displayed changes in wave latency within the auditory pathway. These results reinforce the hypothesis of abnormal neuronal connectivity in the pathophysiology of ASD and shed new light on the genes that increase risk for abnormal sensory perception in ASD.
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Affiliation(s)
- O Mercati
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - G Huguet
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - A Danckaert
- Imagopole, Citech, Institut Pasteur, Paris, France
| | - G André-Leroux
- Institut Pasteur, Unité de Microbiologie Structurale, Paris, France
- CNRS UMR 3528, Paris, France
- INRA, Unité MaIAGE, UR1404, Jouy-en-Josas, France
| | - A Maruani
- Assistance Publique-Hôpitaux de Paris, Child and Adolescent Psychiatry Department, Robert Debré Hospital, Paris, France
| | - M Bellinzoni
- Institut Pasteur, Unité de Microbiologie Structurale, Paris, France
- CNRS UMR 3528, Paris, France
| | - T Rolland
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - L Gouder
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - A Mathieu
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - J Buratti
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - F Amsellem
- Assistance Publique-Hôpitaux de Paris, Child and Adolescent Psychiatry Department, Robert Debré Hospital, Paris, France
| | - M Benabou
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - J Van-Gils
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - A Beggiato
- Assistance Publique-Hôpitaux de Paris, Child and Adolescent Psychiatry Department, Robert Debré Hospital, Paris, France
| | - M Konyukh
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - J-P Bourgeois
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - M J Gazzellone
- Centre for Applied Genomics, Program in Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada
| | - R K C Yuen
- Centre for Applied Genomics, Program in Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada
| | - S Walker
- Centre for Applied Genomics, Program in Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada
| | - M Delépine
- Centre National de Génotypage, Evry, France
| | - A Boland
- Centre National de Génotypage, Evry, France
| | - B Régnault
- Eukaryote Genotyping Platform, Genopole, Institut Pasteur, Paris, France
| | - M Francois
- Assistance Publique-Hôpitaux de Paris, ENT and Head and Neck Surgery Department, Robert Debré Hospital, Paris-VII University, Paris, France
| | - T Van Den Abbeele
- Assistance Publique-Hôpitaux de Paris, ENT and Head and Neck Surgery Department, Robert Debré Hospital, Paris-VII University, Paris, France
| | - A L Mosca-Boidron
- Département de Génétique, CHU Dijon et Université de Bourgogne, Dijon, France
| | - L Faivre
- Département de Génétique, CHU Dijon et Université de Bourgogne, Dijon, France
| | - Y Shimoda
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Japan
| | - K Watanabe
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Japan
| | - D Bonneau
- Département de Biochimie et Génétique, Centre Hospitalier Universitaire, Angers, France
| | - M Rastam
- Department of Clinical Sciences in Lund, Lund University, Lund, Sweden
- Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg, Sweden
| | - M Leboyer
- INSERM U955, Psychiatrie Translationnelle, Créteil, France
- Université Paris Est, Faculté de Médecine, Créteil, France
- Assistance Publique-Hôpitaux de Paris, DHU Pe-PSY, H. Mondor Hospital, Department of Psychiatry, Créteil, France
- FondaMental Foundation, Créteil, France
| | - S W Scherer
- Centre for Applied Genomics, Program in Genetics and Genome Biology, Hospital for Sick Children, Toronto, ON, Canada
- McLaughlin Centre, Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - C Gillberg
- Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg, Sweden
| | - R Delorme
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
- Assistance Publique-Hôpitaux de Paris, Child and Adolescent Psychiatry Department, Robert Debré Hospital, Paris, France
| | - I Cloëz-Tayarani
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
| | - T Bourgeron
- Human Genetics and Cognitive Functions Unit, Institut Pasteur, Paris, France
- CNRS UMR 3571: Genes, Synapses and Cognition, Institut Pasteur, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions, Paris, France
- Gillberg Neuropsychiatry Centre, University of Gothenburg, Gothenburg, Sweden
- FondaMental Foundation, Créteil, France
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21
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Zuko A, Oguro-Ando A, Post H, Taggenbrock RLRE, van Dijk RE, Altelaar AFM, Heck AJR, Petrenko AG, van der Zwaag B, Shimoda Y, Pasterkamp RJ, Burbach JPH. Association of Cell Adhesion Molecules Contactin-6 and Latrophilin-1 Regulates Neuronal Apoptosis. Front Mol Neurosci 2016; 9:143. [PMID: 28018171 PMCID: PMC5156884 DOI: 10.3389/fnmol.2016.00143] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 11/28/2016] [Indexed: 01/06/2023] Open
Abstract
In view of important neurobiological functions of the cell adhesion molecule contactin-6 (Cntn6) that have emerged from studies on null-mutant mice and autism spectrum disorders patients, we set out to examine pathways underlying functions of Cntn6 using a proteomics approach. We identified the cell adhesion GPCR latrophilin-1 (Lphn1, a.k.a. CIRL1/CL, ADGRL1) as a binding partner for Cntn6 forming together a heteromeric cis-complex. Lphn1 expression in cultured neurons caused reduction in neurite outgrowth and increase in apoptosis, which was rescued by coexpression of Cntn6. In cultured neurons derived from Cntn6-/- mice, Lphn1 knockdown reduced apoptosis, suggesting that the observed apoptosis was Lphn1-dependent. In line with these data, the number of apoptotic cells was increased in the cortex of Cntn6-/- mice compared to wild-type littermate controls. These results show that Cntn6 can modulate the activity of Lphn1 by direct binding and suggests that Cntn6 may prevent apoptosis thereby impinging on neurodevelopment.
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Affiliation(s)
- Amila Zuko
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands
| | - Asami Oguro-Ando
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands
| | - Harm Post
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht UniversityUtrecht, Netherlands; Netherlands Proteomics CentreUtrecht, Netherlands
| | - Renske L R E Taggenbrock
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands
| | - Roland E van Dijk
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands
| | - A F Maarten Altelaar
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht UniversityUtrecht, Netherlands; Netherlands Proteomics CentreUtrecht, Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht UniversityUtrecht, Netherlands; Netherlands Proteomics CentreUtrecht, Netherlands
| | - Alexander G Petrenko
- Laboratory of Receptor Cell Biology, Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences Moscow, Russia
| | - Bert van der Zwaag
- Department of Genetics, University Medical Center Utrecht Utrecht, Netherlands
| | - Yasushi Shimoda
- Department of Bioengineering, Nagaoka University of Technology Nagaoka, Japan
| | - R J Pasterkamp
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands
| | - J P H Burbach
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht Utrecht, Netherlands
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22
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Gennarini G, Bizzoca A, Picocci S, Puzzo D, Corsi P, Furley AJW. The role of Gpi-anchored axonal glycoproteins in neural development and neurological disorders. Mol Cell Neurosci 2016; 81:49-63. [PMID: 27871938 DOI: 10.1016/j.mcn.2016.11.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 11/10/2016] [Accepted: 11/14/2016] [Indexed: 01/06/2023] Open
Abstract
This review article focuses on the Contactin (CNTN) subset of the Immunoglobulin supergene family (IgC2/FNIII molecules), whose components share structural properties (the association of Immunoglobulin type C2 with Fibronectin type III domains), as well as a general role in cell contact formation and axonal growth control. IgC2/FNIII molecules include 6 highly related components (CNTN 1-6), associated with the cell membrane via a Glycosyl Phosphatidyl Inositol (GPI)-containing lipid tail. Contactin 1 and Contactin 2 share ~50 (49.38)% identity at the aminoacid level. They are components of the cell surface, from which they may be released in soluble forms. They bind heterophilically to multiple partners in cis and in trans, including members of the related L1CAM family and of the Neurexin family Contactin-associated proteins (CNTNAPs or Casprs). Such interactions are important for organising the neuronal membrane, as well as for modulating the growth and pathfinding of axon tracts. In addition, they also mediate the functional maturation of axons by promoting their interactions with myelinating cells at the nodal, paranodal and juxtaparanodal regions. Such interactions also mediate differential ionic channels (both Na+ and K+) distribution, which is of critical relevance in the generation of the peak-shaped action potential. Indeed, thanks to their interactions with Ankyrin G, Na+ channels map within the nodal regions, where they drive axonal depolarization. However, no ionic channels are found in the flanking Contactin1-containing paranodal regions, where CNTN1 interactions with Caspr1 and with the Ig superfamily component Neurofascin 155 in cis and in trans, respectively, build a molecular barrier between the node and the juxtaparanode. In this region K+ channels are clustered, depending upon molecular interactions with Contactin 2 and with Caspr2. In addition to these functions, the Contactins appear to have also a role in degenerative and inflammatory disorders: indeed Contactin 2 is involved in neurodegenerative disorders with a special reference to the Alzheimer disease, given its ability to work as a ligand of the Alzheimer Precursor Protein (APP), which results in increased Alzheimer Intracellular Domain (AICD) release in a γ-secretase-dependent manner. On the other hand Contactin 1 drives Notch signalling activation via the Hes pathway, which could be consistent with its ability to modulate neuroinflammation events, and with the possibility that Contactin 1-dependent interactions may participate to the pathogenesis of the Multiple Sclerosis and of other inflammatory disorders.
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Affiliation(s)
- Gianfranco Gennarini
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy.
| | - Antonella Bizzoca
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy
| | - Sabrina Picocci
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy
| | - Daniela Puzzo
- Department of Biomedical and Biotechnological Sciences, University of Catania, Italy
| | - Patrizia Corsi
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, Medical School, University of Bari Policlinico. Piazza Giulio Cesare. I-70124 Bari, Italy
| | - Andrew J W Furley
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2NT, UK
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23
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Goodman KM, Yamagata M, Jin X, Mannepalli S, Katsamba PS, Ahlsén G, Sergeeva AP, Honig B, Sanes JR, Shapiro L. Molecular basis of sidekick-mediated cell-cell adhesion and specificity. eLife 2016; 5. [PMID: 27644106 PMCID: PMC5045292 DOI: 10.7554/elife.19058] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/17/2016] [Indexed: 01/06/2023] Open
Abstract
Sidekick (Sdk) 1 and 2 are related immunoglobulin superfamily cell adhesion proteins required for appropriate synaptic connections between specific subtypes of retinal neurons. Sdks mediate cell-cell adhesion with homophilic specificity that underlies their neuronal targeting function. Here we report crystal structures of Sdk1 and Sdk2 ectodomain regions, revealing similar homodimers mediated by the four N-terminal immunoglobulin domains (Ig1-4), arranged in a horseshoe conformation. These Ig1-4 horseshoes interact in a novel back-to-back orientation in both homodimers through Ig1:Ig2, Ig1:Ig1 and Ig3:Ig4 interactions. Structure-guided mutagenesis results show that this canonical dimer is required for both Sdk-mediated cell aggregation (via trans interactions) and Sdk clustering in isolated cells (via cis interactions). Sdk1/Sdk2 recognition specificity is encoded across Ig1-4, with Ig1-2 conferring the majority of binding affinity and differential specificity. We suggest that competition between cis and trans interactions provides a novel mechanism to sharpen the specificity of cell-cell interactions.
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Affiliation(s)
- Kerry M Goodman
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States
| | - Masahito Yamagata
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States.,Center for Brain Science, Harvard University, Cambridge, United States
| | - Xiangshu Jin
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Seetha Mannepalli
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States
| | - Phinikoula S Katsamba
- Howard Hughes Medical Institute, Columbia University, New York, United States.,Department of Systems Biology, Columbia University, New York, United States
| | - Göran Ahlsén
- Howard Hughes Medical Institute, Columbia University, New York, United States.,Department of Systems Biology, Columbia University, New York, United States
| | - Alina P Sergeeva
- Howard Hughes Medical Institute, Columbia University, New York, United States.,Department of Systems Biology, Columbia University, New York, United States
| | - Barry Honig
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Howard Hughes Medical Institute, Columbia University, New York, United States.,Department of Systems Biology, Columbia University, New York, United States.,Department of Medicine, Columbia University, New York, United States.,Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, United States
| | - Joshua R Sanes
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States.,Center for Brain Science, Harvard University, Cambridge, United States
| | - Lawrence Shapiro
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Department of Systems Biology, Columbia University, New York, United States.,Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, United States
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24
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Frei JA, Stoeckli ET. SynCAMs - From axon guidance to neurodevelopmental disorders. Mol Cell Neurosci 2016; 81:41-48. [PMID: 27594578 DOI: 10.1016/j.mcn.2016.08.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 08/28/2016] [Accepted: 08/31/2016] [Indexed: 12/22/2022] Open
Abstract
Many cell adhesion molecules are located at synapses but only few of them can be considered synaptic cell adhesion molecules in the strict sense. Besides the Neurexins and Neuroligins, the LRRTMs (leucine rich repeat transmembrane proteins) and the SynCAMs/CADMs can induce synapse formation when expressed in non-neuronal cells and therefore are true synaptic cell adhesion molecules. SynCAMs (synaptic cell adhesion molecules) are a subfamily of the immunoglobulin superfamily of cell adhesion molecules. As suggested by their name, they were first identified as cell adhesion molecules at the synapse which were sufficient to trigger synapse formation. They also contribute to myelination by mediating axon-glia cell contacts. More recently, their role in earlier stages of neural circuit formation was demonstrated, as they also guide axons both in the peripheral and in the central nervous system. Mutations in SynCAM genes were found in patients diagnosed with autism spectrum disorders. The diverse functions of SynCAMs during development suggest that neurodevelopmental disorders are not only due to defects in synaptic plasticity. Rather, early steps of neural circuit formation are likely to contribute.
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Affiliation(s)
- Jeannine A Frei
- Hussman Institute for Autism, 801 W Baltimore Street, Baltimore, MD 20201, United States
| | - Esther T Stoeckli
- Dept of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
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25
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Usardi A, Iyer K, Sigoillot SM, Dusonchet A, Selimi F. The immunoglobulin-like superfamily member IGSF3 is a developmentally regulated protein that controls neuronal morphogenesis. Dev Neurobiol 2016; 77:75-92. [PMID: 27328461 DOI: 10.1002/dneu.22412] [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: 12/01/2015] [Revised: 06/18/2016] [Accepted: 06/18/2016] [Indexed: 01/06/2023]
Abstract
The establishment of a functional brain depends on the fine regulation and coordination of many processes, including neurogenesis, differentiation, dendritogenesis, axonogenesis, and synaptogenesis. Proteins of the immunoglobulin-like superfamily (IGSF) are major regulators during this sequence of events. Different members of this class of proteins play nonoverlapping functions at specific developmental time-points, as shown in particular by studies of the cerebellum. We have identified a member of the little studied EWI subfamily of IGSF, the protein IGSF3, as a membrane protein expressed in a neuron specific- and time-dependent manner during brain development. In the cerebellum, it is transiently found in membranes of differentiating granule cells, and is particularly concentrated at axon terminals. There it co-localizes with other IGSF proteins with well-known functions in cerebellar development: TAG-1 and L1. Functional analysis shows that IGSF3 controls the differentiation of granule cells, more precisely axonal growth and branching. Biochemical experiments demonstrate that, in the developing brain, IGSF3 is in a complex with the tetraspanin TSPAN7, a membrane protein mutated in several forms of X-linked intellectual disabilities. In cerebellar granule cells, TSPAN7 promotes axonal branching and the size of TSPAN7 clusters is increased by downregulation of IGSF3. Thus IGSF3 is a novel regulator of neuronal morphogenesis that might function through interactions with multiple partners including the tetraspanin TSPAN7. This developmentally regulated protein might thus be at the center of a new signaling pathway controlling brain development. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 75-92, 2017.
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Affiliation(s)
- Alessia Usardi
- Team Mice, Molecules and Synapse Formation, CIRB, Collège de France, CNRS, INSERM, PSL* Research University, Paris, France, 75231, Cedex 05
| | - Keerthana Iyer
- Team Mice, Molecules and Synapse Formation, CIRB, Collège de France, CNRS, INSERM, PSL* Research University, Paris, France, 75231, Cedex 05
| | - Séverine M Sigoillot
- Team Mice, Molecules and Synapse Formation, CIRB, Collège de France, CNRS, INSERM, PSL* Research University, Paris, France, 75231, Cedex 05
| | - Antoine Dusonchet
- Team Mice, Molecules and Synapse Formation, CIRB, Collège de France, CNRS, INSERM, PSL* Research University, Paris, France, 75231, Cedex 05
| | - Fekrije Selimi
- Team Mice, Molecules and Synapse Formation, CIRB, Collège de France, CNRS, INSERM, PSL* Research University, Paris, France, 75231, Cedex 05
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26
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Frei JA, Andermatt I, Gesemann M, Stoeckli ET. The SynCAM synaptic cell adhesion molecules are involved in sensory axon pathfinding by regulating axon-axon contacts. J Cell Sci 2014; 127:5288-302. [PMID: 25335893 DOI: 10.1242/jcs.157032] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Synaptic cell adhesion molecules (SynCAMs) are crucial for synapse formation and plasticity. However, we have previously demonstrated that SynCAMs are also required during earlier stages of neural circuit formation because SynCAM1 and SynCAM2 (also known as CADM1 and CADM2, respectively) are important for the guidance of post-crossing commissural axons. In contrast to the exclusively homophilic cis-interactions reported by previous studies, our previous in vivo results suggested the existence of heterophilic cis-interactions between SynCAM1 and SynCAM2. Indeed, as we show here, the presence of homophilic and heterophilic cis-interactions modulates the interaction of SynCAMs with trans-binding partners, as observed previously for other immunoglobulin superfamily cell adhesion molecules. These in vitro findings are in agreement with results from in vivo studies, which demonstrate a role for SynCAMs in the formation of sensory neural circuits in the chicken embryo. In the absence of SynCAMs, selective axon-axon interactions are perturbed resulting in aberrant pathfinding of sensory axons.
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Affiliation(s)
- Jeannine A Frei
- Institute of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Irwin Andermatt
- Institute of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Matthias Gesemann
- Institute of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Esther T Stoeckli
- Institute of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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27
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Evin G, Barakat A. Critical analysis of the use of β-site amyloid precursor protein-cleaving enzyme 1 inhibitors in the treatment of Alzheimer's disease. Degener Neurol Neuromuscul Dis 2014; 4:1-19. [PMID: 32669897 PMCID: PMC7337240 DOI: 10.2147/dnnd.s41056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 03/06/2014] [Indexed: 01/18/2023] Open
Abstract
Alzheimer’s disease (AD) is the major cause of dementia in the elderly and an unmet clinical challenge. A variety of therapies that are currently under development are directed to the amyloid cascade. Indeed, the accumulation and toxicity of amyloid-β (Aβ) is believed to play a central role in the etiology of the disease, and thus rational interventions are aimed at reducing the levels of Aβ in the brain. Targeting β-site amyloid precursor protein-cleaving enzyme (BACE)-1 represents an attractive strategy, as this enzyme catalyzes the initial and rate-limiting step in Aβ production. Observation of increased levels of BACE1 and enzymatic activity in the brain, cerebrospinal fluid, and platelets of patients with AD and mild cognitive impairment supports the potential benefits of BACE1 inhibition. Numerous potent inhibitors have been generated, and many of these have been proved to lower Aβ levels in the brain of animal models. Over 10 years of intensive research on BACE1 inhibitors has now culminated in advancing half a dozen of these drugs into human trials, yet translating the in vitro and cellular efficacy of BACE1 inhibitors into preclinical and clinical trials represents a challenge. This review addresses the promises and also the potential problems associated with BACE1 inhibitors for AD therapy, as the complex biological function of BACE1 in the brain is becoming unraveled.
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Affiliation(s)
- Genevieve Evin
- Oxidation Biology Laboratory, Mental Health Research Institute, Florey Institute of Neuroscience and Mental Health, University of Melbourne.,Department of Pathology, University of Melbourne, Parkville, VIC, Australia
| | - Adel Barakat
- Department of Pathology, University of Melbourne, Parkville, VIC, Australia
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28
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New insights into the roles of the contactin cell adhesion molecules in neural development. ADVANCES IN NEUROBIOLOGY 2014; 8:165-94. [PMID: 25300137 DOI: 10.1007/978-1-4614-8090-7_8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In vertebrates, the contactin (CNTN) family of neural cell recognition molecules includes six related cell adhesion molecules that play non-overlapping roles in the formation and maintenance of the nervous system. CNTN1 and CNTN2 are the prototypical members of the family and have been involved, through cis- and trans-interactions with distinct cell adhesion molecules, in neural cell migration, axon guidance, and the organization of myelin subdomains. In contrast, the roles of CNTN3-6 are less well characterized although the generation of null mice and the recent identification of a common extracellular binding partner have considerably advanced our grasp of their physiological roles in particular as they relate to the wiring of sensory tissues. In this review, we aim to present a summary of our current understanding of CNTN functions and give an overview of the challenges that lie ahead in understanding the roles these proteins play in nervous system development and maintenance.
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29
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Kong L, Choi RC, Tsim KW, Jing N, Nakayama DK, Wang Z. Distribution and expression of Kirre, an IgSF molecule, during postnatal development of rat cerebellum. Neurosci Lett 2013; 543:22-6. [DOI: 10.1016/j.neulet.2013.03.037] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 03/11/2013] [Accepted: 03/17/2013] [Indexed: 11/24/2022]
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30
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Wirén A, Wright D, Jensen P. Domestication-related variation in social preferences in chickens is affected by genotype on a growth QTL. GENES BRAIN AND BEHAVIOR 2013; 12:330-7. [PMID: 23331324 DOI: 10.1111/gbb.12017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/29/2012] [Accepted: 12/27/2012] [Indexed: 11/26/2022]
Abstract
A growth-related QTL on chicken chromosome 1 has previously been shown to influence domestication behaviour in chickens. In this study, we used Red Junglefowl (RJF) and White Leghorn (WL) as well as the intercross between them to investigate whether stress affects the way birds allocate their time between familiar and unfamiliar conspecifics in a social preference test ('social support seeking'), and how this is related to genotype at specific loci within the growth QTL. Red Junglefowl males spent more time with unfamiliar chickens before the stressful event compared to the other birds, whereas all birds except WL males tended to spend less time with unfamiliar ones after stress. A significant QTL locus was found to influence both social preference under undisturbed circumstances and social support seeking. The WL allele at this QTL was associated not only with a preference for unfamiliar individuals but also with a shift towards familiar ones in response to stress (social support seeking). A second, suggestive QTL also affected social support seeking, but in the opposite direction; the WL allele was associated with increased time spent with unfamiliar individuals. The region contains several possible candidate genes, and gene expression analysis of a number of them showed differential expression between RJF and WL of AVPR2 (receptor for vasotocin), and possibly AVPR1a (another vasotocin receptor) and NRCAM (involved in neural development) in the lower frontal lobes of the brains of RJF and WL animals. These three genes continue to be interesting candidates for the observed behavioural effects.
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Affiliation(s)
- A Wirén
- IFM Biology, AVIAN Behavioural Genomics and Physiology group, Linköping University, Linköping, Sweden
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31
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Mercati O, Danckaert A, André-Leroux G, Bellinzoni M, Gouder L, Watanabe K, Shimoda Y, Grailhe R, De Chaumont F, Bourgeron T, Cloëz-Tayarani I. Contactin 4, -5 and -6 differentially regulate neuritogenesis while they display identical PTPRG binding sites. Biol Open 2013; 2:324-34. [PMID: 23519440 PMCID: PMC3603414 DOI: 10.1242/bio.20133343] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 11/28/2012] [Indexed: 12/22/2022] Open
Abstract
The neural cell-adhesion molecules contactin 4, contactin 5 and contactin 6 are involved in brain development, and disruptions in contactin genes may confer increased risk for autism spectrum disorders (ASD). We describe a co-culture of rat cortical neurons and HEK293 cells overexpressing and delivering the secreted forms of rat contactin 4-6. We quantified their effects on the length and branching of neurites. Contactin 4-6 effects were different depending on the contactin member and duration of co-culture. At 4 days in culture, contactin 4 and -6 increased the length of neurites, while contactin 5 increased the number of roots. Up to 8 days in culture, contactin 6 progressively increased the length of neurites while contactin 5 was more efficient on neurite branching. We studied the molecular sites of interaction between human contactin 4, -5 or -6 and the human Protein Tyrosine Phosphatase Receptor Gamma (PTPRG), a contactin partner, by modeling their 3D structures. As compared to contactin 4, we observed differences in the Ig2 and Ig3 domains of contactin 5 and -6 with the appearance of an omega loop that could adopt three distinct conformations. However, interactive residues between human contactin 4-6 and PTPRG were strictly conserved. We did not observe any differences in PTPRG binding on contactin 5 and -6 either. Our data suggest that the differential contactin effects on neurite outgrowth do not result from distinct interactions with PTPRG. A better understanding of the contactin cellular properties should help elucidate their roles in ASD.
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Affiliation(s)
- Oriane Mercati
- Human Genetics and Cognitive Functions, Institut Pasteur , 75015 Paris , France ; CNRS URA 2182 'Genes, synapses and cognition', Institut Pasteur , 75015 Paris , France ; Université Paris Diderot, Sorbonne Paris Cité, Human Genetics and Cognitive Functions , 75013 Paris , France
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32
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Expanding the Ig superfamily code for laminar specificity in retina: expression and role of contactins. J Neurosci 2013; 32:14402-14. [PMID: 23055510 DOI: 10.1523/jneurosci.3193-12.2012] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Bipolar, amacrine, and retinal ganglion cells elaborate arbors and form synapses within the inner plexiform layer (IPL) of the vertebrate retina. Specific subsets of these neuronal types synapse in one or a few of the ≥10 sublaminae of the IPL. Four closely related Ig superfamily transmembrane adhesion molecules--Sidekick1 (Sdk1), Sdk2, Dscam, and DscamL--are expressed by non-overlapping subsets of chick retinal neurons and promote their lamina-specific arborization (Yamagata and Sanes, 2008). Here, we asked whether contactins (Cntns), six homologs of Sdks and Dscams, are expressed by and play roles in other subsets. In situ hybridization showed that cntn1-5 were differentially expressed by subsets of amacrine cells. Immunohistochemistry showed that each Cntn protein was concentrated in a subset of IPL sublaminae. To assess roles of Cntns in retinal development, we focused on Cntn2. Depletion of Cntn2 by RNA interference markedly reduced the ability of Cntn2-positive cells to restrict their arbors to appropriate sublaminae. Conversely, ectopic expression of cntn2 redirected neurites of transduced neurons to the Cntn2-positive sublaminae. Thus, both loss- and gain-of-function strategies implicate Cntn2 in lamina-specific neurite targeting. Studies in heterologous cells showed that Cntn2 mediates homophilic adhesion, but does not bind detectably to Sdks, Dscams, or other Cntns. Overexpression analysis showed that Cntns1 and 3 can also redirect neurites to appropriate sublaminae. We propose that Cntns, Sdks, and Dscams comprise an Ig superfamily code that uses homophilic interactions to promote lamina-specific targeting of retinal dendrites in IPL.
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Volkmer H, Schreiber J, Rathjen FG. Regulation of adhesion by flexible ectodomains of IgCAMs. Neurochem Res 2012; 38:1092-9. [PMID: 23054071 DOI: 10.1007/s11064-012-0888-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 09/10/2012] [Indexed: 01/06/2023]
Abstract
To perform their diverse biological functions the adhesion activities of the cell adhesion molecules of the immunoglobulin superfamily (IgCAMs) might be regulated by local clustering, proteolytical shedding of their ectodomains or rapid recycling to and from the plasma membrane. Another form of regulation of adhesion might be obtained through flexible ectodomains of IgCAMs which adopt distinct conformations and which in turn modulate their adhesion activity. Here, we discuss variations in the conformation of the extracellular domains of CEACAM1 and CAR that might influence their binding and signaling activities. Furthermore, we concentrate on alternative splicing of single domains and short segments in the extracellular regions of L1 subfamily members that might affect the organization of the N-terminal located Ig-like domains. In particular, we discuss variations of the linker sequence between Ig-like domains 2 and 3 (D2 and D3) that is required for the horseshoe conformation.
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Affiliation(s)
- Hansjürgen Volkmer
- Naturwissenschaftliches und Medizinisches Institut an der Universität Tübingen, Markwiesenstr. 55, 72770 Reutlingen, Germany
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F3/Contactin acts as a modulator of neurogenesis during cerebral cortex development. Dev Biol 2012; 365:133-51. [PMID: 22360968 DOI: 10.1016/j.ydbio.2012.02.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 01/13/2012] [Accepted: 02/10/2012] [Indexed: 12/18/2022]
Abstract
The expression of the cell recognition molecule F3/Contactin (CNTN1) is generally associated with the functions of post-mitotic neurons. In the embryonic cortex, however, we find it expressed by proliferating ventricular zone (VZ) precursors. In contrast to previous findings in the developing cerebellum, F3/Contactin transgenic overexpression in the early cortical VZ promotes proliferation and expands the precursor pool at the expense of neurogenesis. At later stages, when F3/Contactin levels subside, however, neurogenesis resumes, suggesting that F3/Contactin expression in the VZ is inversely related to neurogenesis and plays a role in a feedback control mechanism, regulating the orderly progression of cortical development. The modified F3/Contactin profile therefore results in delayed corticogenesis, as judged by downregulation in upper and lower layer marker expression and by BrdU birth dating, indicating that, in this transgenic model, increased F3/Contactin levels counteract neuronal precursor commitment. These effects also occur in primary cultures and are reproduced by addition of an F3/Fc fusion protein to wild type cultures. Together, these data indicate a completely novel function for F3/Contactin. Parallel changes in the generation of the Notch Intracellular Domain and in the expression of the Hes-1 transcription factor indicate that activation of the Notch pathway plays a role in this phenotype, consistent with previous in vitro reports that F3/Contactin is a Notch1 ligand.
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