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Al-Jamaei AAH, Subramanyam RV, Helder MN, Forouzanfar T, van der Meij EH, Al-Jamei S, de Visscher JGAM. A narrative review of the role of Eph receptors in head and neck squamous cell carcinoma. Oral Dis 2024; 30:833-845. [PMID: 37279081 DOI: 10.1111/odi.14625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 05/10/2023] [Accepted: 05/18/2023] [Indexed: 06/08/2023]
Abstract
Tyrosine kinase receptors (TKR) coordinate a variety of pathological processes in head and neck squamous cell carcinoma (HNSCC), and eventually play a role in patient outcomes. In this review, the role of Eph receptors in HNSCC progression and the possibility of targeting these receptors are illustrated. All relevant studies were identified through a comprehensive search of four electronic databases, including PubMed, Scopus, web of science, and Embase till August 2022. EphA2 and EphB4, along with ephrin-B2, were the most extensively studied proteins in this family. However, overexpression of EphB4 and its ligand ephrin-B2 were the only proteins that consistently showed association with a poor outcome, indicating that these proteins might serve as valuable prognostic markers in HNSCC. High expression of EphA3 and EphB4 was found to play a crucial role in radioresistance of HNSCC. EphB4 loss, in particular, was observed to induce an immunosuppression phenotypic HNSCC. Currently, ongoing clinical trials are investigating the benefits of EphB4-ephrin-B2 blockade in combination with standard of care treatment in HNSCC. Further efforts are needed to explore the biological role and behavioral complexity of this family of TKR in HNSCC with great attention to avoid heterogeneity of HNSCC subsites.
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Affiliation(s)
- Aisha A H Al-Jamaei
- Department of Oral and Maxillofacial Surgery/Oral Pathology, AmsterdamUMC-location VUmc/Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
- Department of Oral Surgery and Oral Medicine, Collage of Dentistry, Al-Razi University, Sana'a, Yemen
| | | | - Marco N Helder
- Department of Oral and Maxillofacial Surgery/Oral Pathology, AmsterdamUMC-location VUmc/Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
| | - Tymour Forouzanfar
- Department of Oral and Maxillofacial Surgery/Oral Pathology, AmsterdamUMC-location VUmc/Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
- Department of Oral and Maxillofacial Surgery, Leiden University Medical Centre (LUMC), Leiden, The Netherlands
| | - Erik H van der Meij
- Department of Oral and Maxillofacial Surgery/Oral Pathology, AmsterdamUMC-location VUmc/Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
- Department of Oral and Maxillofacial Surgery, Medical Centre Leeuwarden, Leeuwarden, The Netherlands
| | - Sayida Al-Jamei
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus TU, Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Jan G A M de Visscher
- Department of Oral and Maxillofacial Surgery/Oral Pathology, AmsterdamUMC-location VUmc/Academic Centre for Dentistry Amsterdam (ACTA), Amsterdam, The Netherlands
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2
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Kim YJ, Oh J, Jung S, Kim CJ, Choi J, Jeon YK, Kim HJ, Kim JW, Suh CH, Lee Y, Im SH, Crotty S, Choi YS. The transcription factor Mef2d regulates B:T synapse-dependent GC-T FH differentiation and IL-21-mediated humoral immunity. Sci Immunol 2023; 8:eadf2248. [PMID: 36961907 PMCID: PMC10311795 DOI: 10.1126/sciimmunol.adf2248] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 02/15/2023] [Indexed: 03/26/2023]
Abstract
Communication between CD4 T cells and cognate B cells is key for the former to fully mature into germinal center-T follicular helper (GC-TFH) cells and for the latter to mount a CD4 T cell-dependent humoral immune response. Although this interaction occurs in a B:T synapse-dependent manner, how CD4 T cells transcriptionally regulate B:T synapse formation remains largely unknown. Here, we report that Mef2d, an isoform of the myocyte enhancer factor 2 (Mef2) transcription factor family, is a critical regulator of this process. In CD4 T cells, Mef2d negatively regulates expression of Sh2d1a, which encodes SLAM-associated protein (SAP), a critical regulator of B:T synapses. We found that Mef2d regulates Sh2d1a expression via DNA binding-dependent transcriptional repression, inhibiting SAP-dependent B:T synapse formation and preventing antigen-specific CD4 T cells from differentiating into GC-TFH cells. Mef2d also impeded IL-21 production by CD4 T cells, an important B cell help signaling molecule, via direct repression of the Il21 gene. In contrast, CD4 T cell-specific disruption of Mef2d led to a substantial increase in GC-TFH differentiation in response to protein immunization, concurrent with enhanced SAP expression. MEF2D mRNA expression inversely correlates with human systemic lupus erythematosus (SLE) patient autoimmune parameters, including circulating TFH-like cell frequencies, autoantibodies, and SLEDAI scores. These findings highlight Mef2d as a pivotal rheostat in CD4 T cells for controlling GC formation and antibody production by B cells.
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Affiliation(s)
- Ye-Ji Kim
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Jeein Oh
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Soohan Jung
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - Chan Johng Kim
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Korea
| | - Jinyong Choi
- Department of Microbiology, Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Yoon Kyung Jeon
- Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Hyun Jik Kim
- Department of Otorhinolaryngology, Seoul National University Hospital, Seoul, Korea
| | - Ji-Won Kim
- Department of Rheumatology, Ajou University School of Medicine, Gyeonggi-do, Korea
| | - Chang-Hee Suh
- Department of Rheumatology, Ajou University School of Medicine, Gyeonggi-do, Korea
| | - Yoontae Lee
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Korea
| | - Sin-Hyeog Im
- Department of Life Sciences, Pohang University of Science and Technology (POSTECH), Pohang, Korea
- ImmunoBiome Inc., Pohang, Korea
- Institute for Convergence Research and Education in Advanced Technology, Yonsei University, Seoul, Korea
| | - Shane Crotty
- Center for Infectious Disease and Vaccine Research, La Jolla Institute for Immunology, La Jolla, CA, USA
- University of California San Diego, Department of Medicine, Division of Infectious Diseases and Global Public Health, La Jolla, CA, USA
| | - Youn Soo Choi
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
- Department of Medicine, Seoul National University College of Medicine, Seoul, Korea
- Transplantation Research Institute, Seoul National University Hospital, Seoul, Korea
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3
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Ferrari FR, Giorgio C, Zappia A, Ballabeni V, Bertoni S, Barocelli E, Scalvini L, Galvani F, Mor M, Lodola A, Tognolini M. Pharmacological characterization of second generation FXR agonists as effective EphA2 antagonists: A successful application of target hopping approach. Biochem Pharmacol 2023; 209:115452. [PMID: 36792038 DOI: 10.1016/j.bcp.2023.115452] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/26/2023] [Accepted: 02/07/2023] [Indexed: 02/16/2023]
Abstract
It is well demonstrated the key role of Eph-ephrin system, specifically of EphA2 receptor, in supporting tumor growth, invasion, metastasis and neovascularization. We previously identified FXR agonists as eligible antagonists of Eph-ephrin system. Herein we characterize new commercially available FXR (Farnesoid X Receptor) agonists as potential Eph ligands including Cilofexor, Nidufexor, Tropifexor, Turofexorate isopropyl and Vonafexor. Our exploration based on molecular modelling investigations and binding assays shows that Cilofexor binds specifically and reversibly to EphA2 receptor with a Ki value in the low micromolar range. Furthermore, Cilofexor interferes with the phosphorylation of EphA2 and the cell retraction and rounding in PC3 prostate cancer cells, both events depending on EphA2 activation. In conclusion, we can confirm that target hopping can be a successful approach to discover new moiety of protein-protein inhibitors.
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Affiliation(s)
- Francesca Romana Ferrari
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Carmine Giorgio
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Alfonso Zappia
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Vigilio Ballabeni
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Simona Bertoni
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Elisabetta Barocelli
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Laura Scalvini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Francesca Galvani
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy
| | - Marco Mor
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy; Microbiome Research Hub, University of Parma, Parco Area delle Scienze 11/A, I-43124 Parma, Italy
| | - Alessio Lodola
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy.
| | - Massimiliano Tognolini
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università degli studi di Parma, Parco Area delle Scienze 27/A, 43124 Parma, Italy.
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4
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Yan K, Bormuth I, Bormuth O, Tutukova S, Renner A, Bessa P, Schaub T, Rosário M, Tarabykin V. TrkB-dependent EphrinA reverse signaling regulates callosal axon fasciculate growth downstream of Neurod2/6. Cereb Cortex 2023; 33:1752-1767. [PMID: 35462405 DOI: 10.1093/cercor/bhac170] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 11/14/2022] Open
Abstract
Abnormal development of corpus callosum is relatively common and causes a broad spectrum of cognitive impairments in humans. We use acallosal Neurod2/6-deficient mice to study callosal axon guidance within the ipsilateral cerebral cortex. Initial callosal tracts form but fail to traverse the ipsilateral cingulum and are not attracted towards the midline in the absence of Neurod2/6. We show that the restoration of Ephrin-A4 (EfnA4) expression in the embryonic neocortex of Neurod2/6-deficient embryos is sufficient to partially rescue targeted callosal axon growth towards the midline. EfnA4 cannot directly mediate reverse signaling within outgrowing axons, but it forms co-receptor complexes with TrkB (Ntrk2). The ability of EfnA4 to rescue the guided growth of a subset of callosal axons in Neurod2/6-deficient mice is abolished by the co-expression of dominant negative TrkBK571N (kinase-dead) or TrkBY515F (SHC-binding deficient) variants, but not by TrkBY816F (PLCγ1-binding deficient). Additionally, EphA4 is repulsive to EfnA4-positive medially projecting axons in organotypic brain slice culture. Collectively, we suggest that EfnA4-mediated reverse signaling acts via TrkB-SHC and is required for ipsilateral callosal axon growth accuracy towards the midline downstream of Neurod family factors.
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Affiliation(s)
- Kuo Yan
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany
| | - Ingo Bormuth
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany
| | - Olga Bormuth
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany.,Institute of Neuroscience, Lobachevsky State University of Nizhny Novgorod, 603950, Nizhny Novgorod Oblast, Russia
| | - Svetlana Tutukova
- Institute of Neuroscience, Lobachevsky State University of Nizhny Novgorod, 603950, Nizhny Novgorod Oblast, Russia.,Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, 634009, Tomsk, Russia
| | - Ana Renner
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany
| | - Paraskevi Bessa
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany
| | - Theres Schaub
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany
| | - Marta Rosário
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany
| | - Victor Tarabykin
- Institute of Cell Biology and Neurobiology, Charité - Universitätsmedizin Berlin, D-10117, Berlin, Germany.,Institute of Neuroscience, Lobachevsky State University of Nizhny Novgorod, 603950, Nizhny Novgorod Oblast, Russia.,Research Institute of Medical Genetics, Tomsk National Research Medical Center of the Russian Academy of Sciences, 634009, Tomsk, Russia
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5
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Washburn HR, Chander P, Srikanth KD, Dalva MB. Transsynaptic Signaling of Ephs in Synaptic Development, Plasticity, and Disease. Neuroscience 2023; 508:137-152. [PMID: 36460219 DOI: 10.1016/j.neuroscience.2022.11.030] [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: 05/02/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 12/03/2022]
Abstract
Synapse formation between neurons is critical for proper circuit and brain function. Prior to activity-dependent refinement of connections between neurons, activity-independent cues regulate the contact and recognition of potential synaptic partners. Formation of a synapse results in molecular recognition events that initiate the process of synaptogenesis. Synaptogenesis requires contact between axon and dendrite, selection of correct and rejection of incorrect partners, and recruitment of appropriate pre- and postsynaptic proteins needed for the establishment of functional synaptic contact. Key regulators of these events are families of transsynaptic proteins, where one protein is found on the presynaptic neuron and the other is found on the postsynaptic neuron. Of these families, the EphBs and ephrin-Bs are required during each phase of synaptic development from target selection, recruitment of synaptic proteins, and formation of spines to regulation of synaptic plasticity at glutamatergic spine synapses in the mature brain. These roles also place EphBs and ephrin-Bs as important regulators of human neurological diseases. This review will focus on the role of EphBs and ephrin-Bs at synapses.
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Affiliation(s)
- Halley R Washburn
- Department of Molecular Biology, Princeton University, Princeton, NJ, USA; Department of Neuroscience, Jefferson Synaptic Biology Center, Sidney Kimmel Medical College at Thomas Jefferson University, 233 South 10th Street, Bluemle Life Sciences Building, Room 324, Philadelphia, PA 19107, USA
| | - Praveen Chander
- Department of Neuroscience, Jefferson Synaptic Biology Center, Sidney Kimmel Medical College at Thomas Jefferson University, 233 South 10th Street, Bluemle Life Sciences Building, Room 324, Philadelphia, PA 19107, USA
| | - Kolluru D Srikanth
- Department of Neuroscience, Jefferson Synaptic Biology Center, Sidney Kimmel Medical College at Thomas Jefferson University, 233 South 10th Street, Bluemle Life Sciences Building, Room 324, Philadelphia, PA 19107, USA
| | - Matthew B Dalva
- Department of Neuroscience, Jefferson Synaptic Biology Center, Sidney Kimmel Medical College at Thomas Jefferson University, 233 South 10th Street, Bluemle Life Sciences Building, Room 324, Philadelphia, PA 19107, USA.
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6
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Gillis RF, Palmour RM. mRNA expression analysis of the hippocampus in a vervet monkey model of fetal alcohol spectrum disorder. J Neurodev Disord 2022; 14:21. [PMID: 35305552 PMCID: PMC8934503 DOI: 10.1186/s11689-022-09427-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 02/10/2022] [Indexed: 11/12/2022] Open
Abstract
Background Fetal alcohol spectrum disorders (FASD) are common, yet preventable developmental disorders that stem from prenatal exposure to alcohol. This exposure leads to a wide array of behavioural and physical problems with a complex and poorly defined biological basis. Molecular investigations to date predominantly use rodent animal models, but because of genetic, developmental and social behavioral similarity, primate models are more relevant. We previously reported reduced cortical and hippocampal neuron levels in an Old World monkey (Chlorocebus sabaeus) model with ethanol exposure targeted to the period of rapid synaptogenesis and report here an initial molecular study of this model. The goal of this study was to evaluate mRNA expression of the hippocampus at two different behavioural stages (5 months, 2 years) corresponding to human infancy and early childhood. Methods Offspring of alcohol-preferring or control dams drank a maximum of 3.5 g ethanol per kg body weight or calorically matched sucrose solution 4 days per week during the last 2 months of gestation. Total mRNA expression was measured with the Affymetrix GeneChip Rhesus Macaque Genome Array in a 2 × 2 study design that interrogated two independent variables, age at sacrifice, and alcohol consumption during gestation. Results and discussion Statistical analysis identified a preferential downregulation of expression when interrogating the factor ‘alcohol’ with a balanced effect of upregulation vs. downregulation for the independent variable ‘age’. Functional exploration of both independent variables shows that the alcohol consumption factor generates broad functional annotation clusters that likely implicate a role for epigenetics in the observed differential expression, while the variable age reliably produced functional annotation clusters predominantly related to development. Furthermore, our data reveals a novel connection between EFNB1 and the FASDs; this is highly plausible both due to the role of EFNB1 in neuronal development as well as its central role in craniofrontal nasal syndrome (CFNS). Fold changes for key genes were subsequently confirmed via qRT-PCR. Conclusion Prenatal alcohol exposure leads to global downregulation in mRNA expression. The cellular interference model of EFNB1 provides a potential clue regarding how genetically susceptible individuals may develop the phenotypic triad generally associated with classic fetal alcohol syndrome. Supplementary Information The online version contains supplementary material available at 10.1186/s11689-022-09427-z.
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7
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Abstract
The EPH receptor tyrosine kinases and their signaling partners, the EPHRINS, comprise a large class of cell signaling molecules that plays diverse roles in development. As cell membrane-anchored signaling molecules, they regulate cellular organization by modulating the strength of cellular contacts, usually by impacting the actin cytoskeleton or cell adhesion programs. Through these cellular functions, EPH/EPHRIN signaling often regulates tissue shape. Indeed, recent evidence indicates that this signaling family is ancient and associated with the origin of multicellularity. Though extensively studied, our understanding of the signaling mechanisms employed by this large family of signaling proteins remains patchwork, and a truly "canonical" EPH/EPHRIN signal transduction pathway is not known and may not exist. Instead, several foundational evolutionarily conserved mechanisms are overlaid by a myriad of tissue -specific functions, though common themes emerge from these as well. Here, I review recent advances and the related contexts that have provided new understanding of the conserved and varied molecular and cellular mechanisms employed by EPH/EPHRIN signaling during development.
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Affiliation(s)
- Jeffrey O Bush
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA, United States; Program in Craniofacial Biology, University of California San Francisco, San Francisco, CA, United States; Institute for Human Genetics, University of California San Francisco, San Francisco, CA, United States; Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, CA, United States.
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8
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N'Tumba-Byn T, Yamada M, Seandel M. Loss of tyrosine kinase receptor Ephb2 impairs proliferation and stem cell activity of spermatogonia in culture†. Biol Reprod 2021; 102:950-962. [PMID: 31836902 DOI: 10.1093/biolre/ioz222] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 10/30/2019] [Accepted: 12/11/2019] [Indexed: 12/17/2022] Open
Abstract
Germline stem and progenitor cells can be extracted from the adult mouse testis and maintained long-term in vitro. Yet, the optimal culture conditions for preserving stem cell activity are unknown. Recently, multiple members of the Eph receptor family were detected in murine spermatogonia, but their roles remain obscure. One such gene, Ephb2, is crucial for maintenance of somatic stem cells and was previously found enriched at the level of mRNA in murine spermatogonia. We detected Ephb2 mRNA and protein in primary adult spermatogonial cultures and hypothesized that Ephb2 plays a role in maintenance of stem cells in vitro. We employed CRISPR-Cas9 targeting and generated stable mutant SSC lines with complete loss of Ephb2. The characteristics of Ephb2-KO cells were interrogated using phenotypic and functional assays. Ephb2-KO SSCs exhibited reduced proliferation compared to wild-type cells, while apoptosis was unaffected. Therefore, we examined whether Ephb2 loss correlates with activity of canonical pathways involved in stem cell self-renewal and proliferation. Ephb2-KO cells had reduced ERK MAPK signaling. Using a lentiviral transgene, Ephb2 expression was rescued in Ephb2-KO cells, which partially restored signaling and proliferation. Transplantation analysis revealed that Ephb2-KO SSCs cultures formed significantly fewer colonies than WT, indicating a role for Ephb2 in preserving stem cell activity of cultured cells. Transcriptome analysis of wild-type and Ephb2-KO SSCs identified Dppa4 and Bnc1 as differentially expressed, Ephb2-dependent genes that are potentially involved in stem cell function. These data uncover for the first time a crucial role for Ephb2 signaling in cultured SSCs.
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Affiliation(s)
- Thierry N'Tumba-Byn
- Department of Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Makiko Yamada
- Department of Surgery, Weill Cornell Medical College, New York, NY, United States of America
| | - Marco Seandel
- Department of Surgery, Weill Cornell Medical College, New York, NY, United States of America
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9
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Ezan J, Moreau MM, Mamo TM, Shimbo M, Decroo M, Richter M, Peyroutou R, Rachel R, Tissir F, de Anda FC, Sans N, Montcouquiol M. Early loss of Scribble affects cortical development, interhemispheric connectivity and psychomotor activity. Sci Rep 2021; 11:9106. [PMID: 33907211 PMCID: PMC8079449 DOI: 10.1038/s41598-021-88147-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 04/01/2021] [Indexed: 12/03/2022] Open
Abstract
Neurodevelopmental disorders arise from combined defects in processes including cell proliferation, differentiation, migration and commissure formation. The evolutionarily conserved tumor-suppressor protein Scribble (Scrib) serves as a nexus to transduce signals for the establishment of apicobasal and planar cell polarity during these processes. Human SCRIB gene mutations are associated with neural tube defects and this gene is located in the minimal critical region deleted in the rare Verheij syndrome. In this study, we generated brain-specific conditional cKO mouse mutants and assessed the impact of the Scrib deletion on brain morphogenesis and behavior. We showed that embryonic deletion of Scrib in the telencephalon leads to cortical thickness reduction (microcephaly) and partial corpus callosum and hippocampal commissure agenesis. We correlated these phenotypes with a disruption in various developmental mechanisms of corticogenesis including neurogenesis, neuronal migration and axonal connectivity. Finally, we show that Scrib cKO mice have psychomotor deficits such as locomotor activity impairment and memory alterations. Altogether, our results show that Scrib is essential for early brain development due to its role in several developmental cellular mechanisms that could underlie some of the deficits observed in complex neurodevelopmental pathologies.
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Affiliation(s)
- Jerome Ezan
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France.
| | - Maité M Moreau
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France
| | - Tamrat M Mamo
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France
| | - Miki Shimbo
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France
| | - Maureen Decroo
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France
| | - Melanie Richter
- Germany Center for Molecular Neurobiology Hamburg (ZMNH), Research Group Neuronal Development, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Ronan Peyroutou
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France
| | - Rivka Rachel
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, NIH, Bethesda, MD, 20892, USA
| | - Fadel Tissir
- Developmental Neurobiology Group, Institute of Neuroscience, University of Louvain, Avenue Mounier 73, Box B1.73.16, 1200, Brussels, Belgium
| | - Froylan Calderon de Anda
- Germany Center for Molecular Neurobiology Hamburg (ZMNH), Research Group Neuronal Development, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nathalie Sans
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France
| | - Mireille Montcouquiol
- Université de Bordeaux, INSERM, Neurocentre Magendie, U1215, 33077, Bordeaux, France.
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10
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Zhou J, Lin Y, Huynh T, Noguchi H, Bush JO, Pleasure SJ. NMDA receptors control development of somatosensory callosal axonal projections. eLife 2021; 10:59612. [PMID: 33661095 PMCID: PMC7959694 DOI: 10.7554/elife.59612] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 02/22/2021] [Indexed: 11/25/2022] Open
Abstract
Callosal projections from primary somatosensory cortex (S1) are key for processing somatosensory inputs and integrating sensory-motor information. How the callosal innervation pattern in S1 is formed during early postnatal development is not clear. We found that the normal termination pattern of these callosal projections is disrupted in cortex specific NMDAR mutants. Rather than projecting selectively to the primary/secondary somatosensory cortex (S1/S2) border, axons were uniformly distributed throughout S1. In addition, the density of this projection increased over postnatal life until the mice died by P30. By combining genetic and antibody-mediated loss of function, we demonstrated that it is GluN2B-containing NMDA receptors in target S1 that mediate this guidance phenotype, thus playing a central role in interhemispheric connectivity. Furthermore, we found that this function of NMDA receptors in callosal circuit formation is independent of ion channel function and works with the EPHRIN-B/EPHB system. Thus, NMDAR in target S1 cortex regulates the formation callosal circuits perhaps by modulating EPH-dependent repulsion.
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Affiliation(s)
- Jing Zhou
- Department of Neurology, University of California, San Francisco, San Francisco, United States.,Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, United States
| | - Yong Lin
- Department of Neurology, University of California, San Francisco, San Francisco, United States.,Department of Neurological Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Trung Huynh
- Department of Neurology, University of California, San Francisco, San Francisco, United States.,Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, United States
| | - Hirofumi Noguchi
- Department of Neurology, University of California, San Francisco, San Francisco, United States.,Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, United States
| | - Jeffrey O Bush
- Department of Cell and Tissue Biology, Program in Craniofacial Biology and Institute for Human Genetics, University of California, San Francisco, San Francisco, United States.,Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, United States
| | - Samuel J Pleasure
- Department of Neurology, University of California, San Francisco, San Francisco, United States.,Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, United States.,Programs in Neuroscience and Developmental Stem Cell Biology, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Kavli Institute for Fundamental Neuroscience, San Francisco, United States
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11
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De León Reyes NS, Bragg-Gonzalo L, Nieto M. Development and plasticity of the corpus callosum. Development 2020; 147:147/18/dev189738. [PMID: 32988974 DOI: 10.1242/dev.189738] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The corpus callosum (CC) connects the cerebral hemispheres and is the major mammalian commissural tract. It facilitates bilateral sensory integration and higher cognitive functions, and is often affected in neurodevelopmental diseases. Here, we review the mechanisms that contribute to the development of CC circuits in animal models and humans. These species comparisons reveal several commonalities. First, there is an early period of massive axonal projection. Second, there is a postnatal temporal window, varying between species, in which early callosal projections are selectively refined. Third, sensory-derived activity influences axonal refinement. We also discuss how defects in CC formation can lead to mild or severe CC congenital malformations.
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Affiliation(s)
- Noelia S De León Reyes
- Department of Cellular and Molecular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, (CNB-CSIC) Campus de Cantoblanco, Darwin 3, 28049 Madrid, Spain
| | - Lorena Bragg-Gonzalo
- Department of Cellular and Molecular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, (CNB-CSIC) Campus de Cantoblanco, Darwin 3, 28049 Madrid, Spain
| | - Marta Nieto
- Department of Cellular and Molecular Biology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas, (CNB-CSIC) Campus de Cantoblanco, Darwin 3, 28049 Madrid, Spain
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12
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Astrocytic Ephrin-B1 Controls Excitatory-Inhibitory Balance in Developing Hippocampus. J Neurosci 2020; 40:6854-6871. [PMID: 32801156 DOI: 10.1523/jneurosci.0413-20.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/08/2020] [Accepted: 07/20/2020] [Indexed: 12/12/2022] Open
Abstract
Astrocytes are implicated in synapse formation and elimination, which are associated with developmental refinements of neuronal circuits. Astrocyte dysfunctions are also linked to synapse pathologies associated with neurodevelopmental disorders and neurodegenerative diseases. Although several astrocyte-derived secreted factors are implicated in synaptogenesis, the role of contact-mediated glial-neuronal interactions in synapse formation and elimination during development is still unknown. In this study, we examined whether the loss or overexpression of the membrane-bound ephrin-B1 in astrocytes during postnatal day (P) 14-28 period would affect synapse formation and maturation in the developing hippocampus. We found enhanced excitation of CA1 pyramidal neurons in astrocyte-specific ephrin-B1 KO male mice, which coincided with a greater vGlut1/PSD95 colocalization, higher dendritic spine density, and enhanced evoked AMPAR and NMDAR EPSCs. In contrast, EPSCs were reduced in CA1 neurons neighboring ephrin-B1-overexpressing astrocytes. Overexpression of ephrin-B1 in astrocytes during P14-28 developmental period also facilitated evoked IPSCs in CA1 neurons, while evoked IPSCs and miniature IPSC amplitude were reduced following astrocytic ephrin-B1 loss. Lower numbers of parvalbumin-expressing cells and a reduction in the inhibitory VGAT/gephyrin-positive synaptic sites on CA1 neurons in the stratum pyramidale and stratum oriens layers of KO hippocampus may contribute to reduced inhibition and higher excitation. Finally, dysregulation of excitatory/inhibitory balance in KO male mice is most likely responsible for impaired sociability observed in these mice. The ability of astrocytic ephrin-B1 to influence both excitatory and inhibitory synapses during development can potentially contribute to developmental refinement of neuronal circuits.SIGNIFICANCE STATEMENT This report establishes a link between astrocytes and the development of excitatory and inhibitory balance in the mouse hippocampus during early postnatal development. We provide new evidence that astrocytic ephrin-B1 differentially regulates development of excitatory and inhibitory circuits in the hippocampus during early postnatal development using a multidisciplinary approach. The ability of astrocytic ephrin-B1 to influence both excitatory and inhibitory synapses during development can potentially contribute to developmental refinement of neuronal circuits and associated behaviors. Given widespread and growing interest in the astrocyte-mediated mechanisms that regulate synapse development, and the role of EphB receptors in neurodevelopmental disorders, these findings establish a foundation for future studies of astrocytes in clinically relevant conditions.
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13
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Ye X, Qiu Y, Gao Y, Wan D, Zhu H. A Subtle Network Mediating Axon Guidance: Intrinsic Dynamic Structure of Growth Cone, Attractive and Repulsive Molecular Cues, and the Intermediate Role of Signaling Pathways. Neural Plast 2019; 2019:1719829. [PMID: 31097955 PMCID: PMC6487106 DOI: 10.1155/2019/1719829] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 02/25/2019] [Accepted: 03/06/2019] [Indexed: 01/01/2023] Open
Abstract
A fundamental feature of both early nervous system development and axon regeneration is the guidance of axonal projections to their targets in order to assemble neural circuits that control behavior. In the navigation process where the nerves grow toward their targets, the growth cones, which locate at the tips of axons, sense the environment surrounding them, including varies of attractive or repulsive molecular cues, then make directional decisions to adjust their navigation journey. The turning ability of a growth cone largely depends on its highly dynamic skeleton, where actin filaments and microtubules play a very important role in its motility. In this review, we summarize some possible mechanisms underlying growth cone motility, relevant molecular cues, and signaling pathways in axon guidance of previous studies and discuss some questions regarding directions for further studies.
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Affiliation(s)
- Xiyue Ye
- College of Pharmaceutical Sciences and Traditional Chinese Medicine, Southwest University, Chongqing 400715, China
- Chongqing Engineering Research Center for Pharmacological Evaluation, Chongqing 400715, China
- Engineering Research Center for Chongqing Pharmaceutical Process and Quality Control, Chongqing 400715, China
| | - Yan Qiu
- College of Pharmaceutical Sciences and Traditional Chinese Medicine, Southwest University, Chongqing 400715, China
- Chongqing Engineering Research Center for Pharmacological Evaluation, Chongqing 400715, China
- Engineering Research Center for Chongqing Pharmaceutical Process and Quality Control, Chongqing 400715, China
| | - Yuqing Gao
- College of Pharmaceutical Sciences and Traditional Chinese Medicine, Southwest University, Chongqing 400715, China
- Chongqing Engineering Research Center for Pharmacological Evaluation, Chongqing 400715, China
- Engineering Research Center for Chongqing Pharmaceutical Process and Quality Control, Chongqing 400715, China
| | - Dong Wan
- Department of Emergency, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
| | - Huifeng Zhu
- College of Pharmaceutical Sciences and Traditional Chinese Medicine, Southwest University, Chongqing 400715, China
- Chongqing Engineering Research Center for Pharmacological Evaluation, Chongqing 400715, China
- Engineering Research Center for Chongqing Pharmaceutical Process and Quality Control, Chongqing 400715, China
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14
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Niethamer TK, Bush JO. Getting direction(s): The Eph/ephrin signaling system in cell positioning. Dev Biol 2019; 447:42-57. [PMID: 29360434 PMCID: PMC6066467 DOI: 10.1016/j.ydbio.2018.01.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/21/2017] [Accepted: 01/18/2018] [Indexed: 12/16/2022]
Abstract
In vertebrates, the Eph/ephrin family of signaling molecules is a large group of membrane-bound proteins that signal through a myriad of mechanisms and effectors to play diverse roles in almost every tissue and organ system. Though Eph/ephrin signaling has functions in diverse biological processes, one core developmental function is in the regulation of cell position and tissue morphology by regulating cell migration and guidance, cell segregation, and boundary formation. Often, the role of Eph/ephrin signaling is to translate patterning information into physical movement of cells and changes in morphology that define tissue and organ systems. In this review, we focus on recent advances in the regulation of these processes, and our evolving understanding of the in vivo signaling mechanisms utilized in distinct developmental contexts.
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Affiliation(s)
- Terren K Niethamer
- Department of Cell and Tissue Biology, Program in Craniofacial Biology, and Institute of Human Genetics, University of California at San Francisco, San Francisco, CA 94143, USA
| | - Jeffrey O Bush
- Department of Cell and Tissue Biology, Program in Craniofacial Biology, and Institute of Human Genetics, University of California at San Francisco, San Francisco, CA 94143, USA.
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15
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Tian M, Zhou Y, Qiu L, Liu F, Jin L, Li W, Zhang L. NL1 expression level in Nrx1β and the excitability of PV interneurons in mice with POCD. Exp Ther Med 2019; 17:3117-3123. [PMID: 30936983 PMCID: PMC6434254 DOI: 10.3892/etm.2019.7322] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 01/10/2019] [Indexed: 01/03/2023] Open
Abstract
Effects of NL1 on the expression level of neurexin-1β (Nrx1β) and the excitability of parvalbumin (PV) interneurons in mice with postoperative cognitive dysfunction (POCD) were explored. Eighty 10-month-old C57BL/6 male mice were randomly divided into four groups: control group, control+empty vector group (Control+EV), anesthesia surgery+empty vector group (POCD+EV group) and anesthesia+NL1 overexpression group (POCD+NL1 group), (n=20 per group). The behavioral differences of mice in the four groups were analyzed by means of open field test and fear conditioning test. The expression levels of NL1, PV and Nrx1β were detected by western blot analysis, and the binding between NL1 and Nrx1β was determined by co-immunoprecipitation. The expression level of postsynaptic density protein 95 (PSD95) in hippocampus and changes in the excitability of PV interneurons were further detected. Control and Control+EV groups had no significant difference in each index (P>0.05). Compared with Control+EV group, the percentage of cued freezing time in POCD+EV group decreased significantly, while percentage of cued freezing time was significantly increased in POCD+NL1 group and POCD+EV group (P<0.01). The differences in freezing time were not statistically significant among the 4 groups in the tone-related fear test (P>0.05). Then NL1 was overexpressed in mice with POCD, the protein levels of PV, Nrx1β and PSD95 were subsequently increased, and the interaction between NL1 and Nrx1β protein was enhanced, dramatically increasing the excitability of PV interneurons. The overexpression of NL1 can upregulate the expression levels of PV, Nrx1β and PSD95 in mice with POCD, enhance the interaction between NL1 and Nrx1β and further increase the excitability of PV interneurons, thus restoring the hippocampus-dependent memorial and cognitive impairment in POCD.
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Affiliation(s)
- Mi Tian
- Department of Anesthesiology, Nanjing General Hospital, Nanjing, Jiangsu 210000, P.R. China
| | - Yuan Zhou
- Department of Neurosurgery, Nanjing General Hospital, Nanjing, Jiangsu 210000, P.R. China
| | - Lili Qiu
- Department of Anesthesiology, Zhongda Hospital Southeast University, Nanjing, Jiangsu 210000, P.R. China
| | - Fangfang Liu
- Department of Anesthesiology, Nanjing General Hospital, Nanjing, Jiangsu 210000, P.R. China
| | - Li Jin
- Department of Anesthesiology, Nanjing General Hospital, Nanjing, Jiangsu 210000, P.R. China
| | - Weiyan Li
- Department of Anesthesiology, Nanjing General Hospital, Nanjing, Jiangsu 210000, P.R. China
| | - Lidong Zhang
- Department of Anesthesiology, Nanjing General Hospital, Nanjing, Jiangsu 210000, P.R. China
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16
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Functional Consequences of Synapse Remodeling Following Astrocyte-Specific Regulation of Ephrin-B1 in the Adult Hippocampus. J Neurosci 2018; 38:5710-5726. [PMID: 29793972 DOI: 10.1523/jneurosci.3618-17.2018] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 05/13/2018] [Accepted: 05/15/2018] [Indexed: 01/22/2023] Open
Abstract
Astrocyte-derived factors can control synapse formation and functions, making astrocytes an attractive target for regulating neuronal circuits and associated behaviors. Abnormal astrocyte-neuronal interactions are also implicated in neurodevelopmental disorders and neurodegenerative diseases associated with impaired learning and memory. However, little is known about astrocyte-mediated mechanisms that regulate learning and memory. Here, we propose astrocytic ephrin-B1 as a regulator of synaptogenesis in adult hippocampus and mouse learning behaviors. We found that astrocyte-specific ablation of ephrin-B1 in male mice triggers an increase in the density of immature dendritic spines and excitatory synaptic sites in the adult CA1 hippocampus. However, the prevalence of immature dendritic spines is associated with decreased evoked postsynaptic firing responses in CA1 pyramidal neurons, suggesting impaired maturation of these newly formed and potentially silent synapses or increased excitatory drive on the inhibitory neurons resulting in the overall decreased postsynaptic firing. Nevertheless, astrocyte-specific ephrin-B1 knock-out male mice exhibit normal acquisition of fear memory but enhanced contextual fear memory recall. In contrast, overexpression of astrocytic ephrin-B1 in the adult CA1 hippocampus leads to the loss of dendritic spines, reduced excitatory input, and impaired contextual memory retention. Our results suggest that astrocytic ephrin-B1 may compete with neuronal ephrin-B1 and mediate excitatory synapse elimination through its interactions with neuronal EphB receptors. Indeed, a deletion of neuronal EphB receptors impairs the ability of astrocytes expressing functional ephrin-B1 to engulf synaptosomes in vitro Our findings demonstrate that astrocytic ephrin-B1 regulates long-term contextual memory by restricting new synapse formation in the adult hippocampus.SIGNIFICANCE STATEMENT These studies address a gap in our knowledge of astrocyte-mediated regulation of learning and memory by unveiling a new role for ephrin-B1 in astrocytes and elucidating new mechanisms by which astrocytes regulate learning. Our studies explore the mechanisms underlying astrocyte regulation of hippocampal circuit remodeling during learning using new genetic tools that target ephrin-B signaling in astrocytes in vivo On a subcellular level, astrocytic ephrin-B1 may compete with neuronal ephrin-B1 and trigger astrocyte-mediated elimination of EphB receptor-containing synapses. Given the role EphB receptors play in neurodevelopmental disorders and neurodegenerative diseases, these findings establish a foundation for future studies of astrocyte-mediated synaptogenesis in clinically relevant conditions that can help to guide the development of clinical applications for a variety of neurological disorders.
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17
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Mire E, Hocine M, Bazellières E, Jungas T, Davy A, Chauvet S, Mann F. Developmental Upregulation of Ephrin-B1 Silences Sema3C/Neuropilin-1 Signaling during Post-crossing Navigation of Corpus Callosum Axons. Curr Biol 2018; 28:1768-1782.e4. [PMID: 29779877 DOI: 10.1016/j.cub.2018.04.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 02/23/2018] [Accepted: 04/06/2018] [Indexed: 01/09/2023]
Abstract
The corpus callosum is the largest commissure in the brain, whose main function is to ensure communication between homotopic regions of the cerebral cortex. During fetal development, corpus callosum axons (CCAs) grow toward and across the brain midline and then away on the contralateral hemisphere to their targets. A particular feature of this circuit, which raises a key developmental question, is that the outgoing trajectory of post-crossing CCAs is mirror-symmetric with the incoming trajectory of pre-crossing axons. Here, we show that post-crossing CCAs switch off their response to axon guidance cues, among which the secreted Semaphorin-3C (Sema3C), that act as attractants for pre-crossing axons on their way to the midline. This change is concomitant with an upregulation of the surface protein Ephrin-B1, which acts in CCAs to inhibit Sema3C signaling via interaction with the Neuropilin-1 (Nrp1) receptor. This silencing activity is independent of Eph receptors and involves a N-glycosylation site (N-139) in the extracellular domain of Ephrin-B1. Together, our results reveal a molecular mechanism, involving interaction between the two unrelated guidance receptors Ephrin-B1 and Nrp1, that is used to control the navigation of post-crossing axons in the corpus callosum.
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Affiliation(s)
- Erik Mire
- Aix Marseille Univ, CNRS, IBDM, 13288 Marseille, France.
| | | | | | - Thomas Jungas
- Centre de Biologie du Développement (CBD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 Route de Narbonne, 31062 Toulouse, France
| | - Alice Davy
- Centre de Biologie du Développement (CBD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 118 Route de Narbonne, 31062 Toulouse, France
| | | | - Fanny Mann
- Aix Marseille Univ, CNRS, IBDM, 13288 Marseille, France.
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18
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Laidlaw BJ, Schmidt TH, Green JA, Allen CDC, Okada T, Cyster JG. The Eph-related tyrosine kinase ligand Ephrin-B1 marks germinal center and memory precursor B cells. J Exp Med 2017; 214:639-649. [PMID: 28143955 PMCID: PMC5339677 DOI: 10.1084/jem.20161461] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/19/2016] [Accepted: 12/19/2016] [Indexed: 02/01/2023] Open
Abstract
Identification of germinal center (GC) B cells is typically reliant on the use of surface activation markers that exhibit a wide range of expression. Here, we identify Ephrin-B1, a ligand for Eph-related receptor tyrosine kinases, as a specific marker of mature GC B cells. The number of Ephrin-B1+ GC B cells increases during the course of an immune response with Ephrin-B1+ GC B cells displaying elevated levels of Bcl6, S1pr2, and Aicda relative to their Ephrin-B1- counterparts. We further identified a small proportion of recently dividing, somatically mutated Ephrin-B1+ GC B cells that have begun to down-regulate Bcl6 and S1pr2 and express markers associated with memory B cells, such as CD38 and EBI2. Transcriptional analysis indicates that these cells are developmentally related to memory B cells, and likely represent a population of GC memory precursor (PreMem) B cells. GC PreMem cells display enhanced survival relative to bulk GC B cells, localize near the edge of the GC, and are predominantly found within the light zone. These findings offer insight into the significant heterogeneity that exists within the GC B cell population and provide tools to further dissect signals regulating the differentiation of GC B cells.
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Affiliation(s)
- Brian J Laidlaw
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143
| | - Timothy H Schmidt
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143
| | - Jesse A Green
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143
| | - Christopher D C Allen
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
- Department of Anatomy, Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA 94143
- Sandler Asthma Basic Research Center, University of California, San Francisco, San Francisco, CA 94143
| | - Takaharu Okada
- Laboratory for Tissue Dynamics, Institute of Physical and Chemical Research Center for Integrative Medical Sciences (IMS-RCAI), Yokohama, Kanagawa 230-0045, Japan
| | - Jason G Cyster
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143
- Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94143
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19
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O'Neill AK, Kindberg AA, Niethamer TK, Larson AR, Ho HYH, Greenberg ME, Bush JO. Unidirectional Eph/ephrin signaling creates a cortical actomyosin differential to drive cell segregation. J Cell Biol 2016; 215:217-229. [PMID: 27810913 PMCID: PMC5084648 DOI: 10.1083/jcb.201604097] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 09/13/2016] [Indexed: 01/01/2023] Open
Abstract
Eph/ephrins drive cell segregation and boundary formation. O’Neill et al. discover that segregation is driven by unidirectional kinase-dependent EphB signaling. Unidirectional signaling generates a cortical actin differential between ephrin-B1– and EphB2-expressing cells and requires ROCK activity for cell segregation. Cell segregation is the process by which cells self-organize to establish developmental boundaries, an essential step in tissue formation. Cell segregation is a common outcome of Eph/ephrin signaling, but the mechanisms remain unclear. In craniofrontonasal syndrome, X-linked mosaicism for ephrin-B1 expression has been hypothesized to lead to aberrant Eph/ephrin-mediated cell segregation. Here, we use mouse genetics to exploit mosaicism to study cell segregation in the mammalian embryo and integrate live-cell imaging to examine the underlying cellular and molecular mechanisms. Our data demonstrate that dramatic ephrin-B1–mediated cell segregation occurs in the early neuroepithelium. In contrast to the paradigm that repulsive bidirectional signaling drives cell segregation, unidirectional EphB kinase signaling leads to cell sorting by the Rho kinase–dependent generation of a cortical actin differential between ephrin-B1– and EphB-expressing cells. These results define mechanisms of Eph/ephrin-mediated cell segregation, implicating unidirectional regulation of cortical actomyosin contractility as a key effector of this fundamental process.
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Affiliation(s)
- Audrey K O'Neill
- Department of Cell and Tissue Biology, Program in Craniofacial Biology and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA 94143
| | - Abigail A Kindberg
- Department of Cell and Tissue Biology, Program in Craniofacial Biology and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA 94143.,Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Terren K Niethamer
- Department of Cell and Tissue Biology, Program in Craniofacial Biology and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA 94143.,Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Andrew R Larson
- Department of Cell and Tissue Biology, Program in Craniofacial Biology and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA 94143
| | - Hsin-Yi Henry Ho
- Department of Cell Biology and Human Anatomy, University of California Davis School of Medicine, Davis, CA 95817.,Department of Neurobiology, Harvard Medical School, Boston, MA 02115
| | | | - Jeffrey O Bush
- Department of Cell and Tissue Biology, Program in Craniofacial Biology and Institute for Human Genetics, University of California, San Francisco, San Francisco, CA 94143 .,Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143.,Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA 94143
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20
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Rundle CH, Xing W, Lau KHW, Mohan S. Bidirectional ephrin signaling in bone. Osteoporos Sarcopenia 2016; 2:65-76. [PMID: 30775469 PMCID: PMC6372807 DOI: 10.1016/j.afos.2016.05.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/27/2016] [Accepted: 05/04/2016] [Indexed: 12/12/2022] Open
Abstract
The interaction between ephrin ligands (efn) and their receptors (Eph) is capable of inducing forward signaling, from ligand to receptor, as well as reverse signaling, from receptor to ligand. The ephrins are widely expressed in many tissues, where they mediate cell migration and adherence, properties that make the efn-Eph signaling critically important in establishing and maintaining tissue boundaries. The efn-Eph system has also received considerable attention in skeletal tissues, as ligand and receptor combinations are predicted to mediate interactions between the different types of cells that regulate bone development and homeostasis. This review summarizes our current understanding of efn-Eph signaling with a particular focus on the expression and functions of ephrins and their receptors in bone.
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Affiliation(s)
- Charles H Rundle
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA.,Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA
| | - Weirong Xing
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA.,Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA
| | - Kin-Hing William Lau
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA.,Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, VA Loma Linda Healthcare System, 11201 Benton St, Loma Linda, CA 92357, USA.,Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA
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21
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Abstract
Ephrins and Eph receptors enable contact-mediated interactions between cells at every stage of nervous system development. In spite of their broad binding affinities, Eph proteins facilitate specificity in neuronal migration and axon targeting. This review focuses on recent studies that demonstrate how these proteins interact with each other, and with other signaling pathways, to guide specificity in a diverse set of developmental processes.
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Affiliation(s)
- Karina S Cramer
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
| | - Ilona J Miko
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, CA, USA
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22
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Ephrin-B3 coordinates timed axon targeting and amygdala spinogenesis for innate fear behaviour. Nat Commun 2016; 7:11096. [PMID: 27008987 PMCID: PMC4820848 DOI: 10.1038/ncomms11096] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Accepted: 02/19/2016] [Indexed: 12/20/2022] Open
Abstract
Innate emotion response to environmental stimuli is a fundamental brain function that is controlled by specific neural circuits. Dysfunction of early emotional circuits may lead to neurodevelopmental disorders such as autism and schizophrenia. However, how the functional circuits are formed to prime initial emotional behaviours remain elusive. We reveal here using gene-targeted mutations an essential role for ephrin-B3 ligand-like activity in the development of innate fear in the neonatal brain. We further demonstrate that ephrin-B3 controls axon targeting and coordinates spinogenesis and neuronal activity within the amygdala. The morphological and behavioural abnormalities in ephrin-B3 mutant mice are rescued by conditional knock-in of wild-type ephrin-B3 during the critical period when axon targeting and fear responses are initiated. Our results thus define a key axonal molecule that participates in the wiring of amygdala circuits and helps bring about fear emotion during the important adolescence period.
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23
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Yu Y, Liu M, Ng TT, Huang F, Nie Y, Wang R, Yao ZP, Li Z, Xia J. PDZ-Reactive Peptide Activates Ephrin-B Reverse Signaling and Inhibits Neuronal Chemotaxis. ACS Chem Biol 2016; 11:149-58. [PMID: 26524220 DOI: 10.1021/acschembio.5b00889] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Intracellular reactions on nonenzymatic proteins that activate cellular signals are rarely found. We report one example here that a designed peptide derivative undergoes a nucleophilic reaction specifically with a cytosolic PDZ protein inside cells. This reaction led to the activation of ephrin-B reverse signaling, which subsequently inhibited SDF-1 induced neuronal chemotaxis of human neuroblastoma cells and mouse cerebellar granule neurons. Our work provides direct evidence that PDZ-RGS3 bridges ephrin-B reverse signaling and SDF-1 induced G protein signaling for the first time.
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Affiliation(s)
- Yongsheng Yu
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Miao Liu
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Tsz Tsun Ng
- Food Safety and Technology Research Centre, State Key Laboratory
of Chirosciences and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong
Kong SAR, China
| | - Feng Huang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Yunyu Nie
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Rui Wang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Zhong-Ping Yao
- Food Safety and Technology Research Centre, State Key Laboratory
of Chirosciences and Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong
Kong SAR, China
| | - Zigang Li
- Laboratory of Chemical
Genomics, School of Chemical Biology and Biotechnology, Shenzhen Graduate School of Peking University, Shenzhen, 518055, China
| | - Jiang Xia
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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Hakanen J, Salminen M. Defects in neural guidepost structures and failure to remove leptomeningeal cells from the septal midline behind the interhemispheric fusion defects in Netrin1 deficient mice. Int J Dev Neurosci 2015; 47:206-15. [PMID: 26397040 DOI: 10.1016/j.ijdevneu.2015.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 08/19/2015] [Accepted: 08/19/2015] [Indexed: 11/18/2022] Open
Abstract
Corpus callosum (CC) is the largest commissural tract in mammalian brain and it acts to coordinate information between the two cerebral hemispheres. During brain development CC forms at the boundary area between the cortex and the septum and special transient neural and glial guidepost structures in this area are thought to be critical for CC formation. In addition, it is thought that the fusion of the two hemispheres in the septum area is a prerequisite for CC formation. However, very little is known of the molecular mechanisms behind the fusion of the two hemispheres. Netrin1 (NTN1) acts as an axon guidance molecule in the developing central nervous system and Ntn1 deficiency leads to the agenesis of CC in mouse. Here we have analyzed Ntn1 deficient mice to better understand the reasons behind the observed lack of CC. We show that Ntn1 deficiency leads to defects in neural, but not in glial guidepost structures that may contribute to the agenesis of CC. In addition, Nnt1 was expressed by the leptomeningeal cells bordering the two septal walls prior to fusion. Normally these cells are removed when the septal fusion occurs. At the same time, the Laminin containing basal lamina produced by the leptomeningeal cells is disrupted in the midline area to allow the cells to mix and the callosal axons to cross. In Ntn1 deficient embryos however, the leptomeninges and the basal lamina were not removed properly from the midline area and the septal fusion did not occur. Thus, NTN1 contributes to the formation of the CC by promoting the preceding removal of the midline leptomeningeal cells and interhemispheric fusion.
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Affiliation(s)
- Janne Hakanen
- Department of Veterinary Biosciences, University of Helsinki, Finland.
| | - Marjo Salminen
- Department of Veterinary Biosciences, University of Helsinki, Finland.
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25
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Craniofrontonasal dysplasia: variability of the frontonasal suture and implications for treatment. J Craniofac Surg 2015; 24:1303-6. [PMID: 23851793 DOI: 10.1097/scs.0b013e3182942b5c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Craniofrontonasal dysplasia's (CFND's) phenotypic range includes hypertelorism, coronal craniosynostosis, frontonasal dysplasia, and digital anomalies. The variable expression is paradoxical for an X-linked syndrome because hemizygous males are less affected than heterozygous females. We describe a case of CFND due to a c.30>T EFNB1 gene mutation. In place of the typical craniosynostosis found in CFND, she presented with a superiorly displaced nasion and an anomalously positioned frontonasal suture. This report reveals an unreported malformation in CFND and its surgical implications.
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26
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Robichaux MA, Chenaux G, Ho HYH, Soskis MJ, Greenberg ME, Henkemeyer M, Cowan CW. EphB1 and EphB2 intracellular domains regulate the formation of the corpus callosum and anterior commissure. Dev Neurobiol 2015; 76:405-20. [PMID: 26148571 DOI: 10.1002/dneu.22323] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/28/2015] [Accepted: 06/30/2015] [Indexed: 12/24/2022]
Abstract
The two cortical hemispheres of the mammalian forebrain are interconnected by major white matter tracts, including the corpus callosum (CC) and the posterior branch of the anterior commissure (ACp), that bridge the telencephalic midline. We show here that the intracellular signaling domains of the EphB1 and EphB2 receptors are critical for formation of both the ACp and CC. We observe partial and complete agenesis of the corpus callosum, as well as highly penetrant ACp misprojection phenotypes in truncated EphB1/2 mice that lack intracellular signaling domains. Consistent with the roles for these receptors in formation of the CC and ACp, we detect expression of these receptors in multiple brain regions associated with the formation of these forebrain structures. Taken together, our findings suggest that a combination of forward and reverse EphB1/2 receptor-mediated signaling contribute to ACp and CC axon guidance.
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Affiliation(s)
- Michael A Robichaux
- Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, Massachusetts, 02478.,Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, Texas, 75390
| | - George Chenaux
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, Texas, 75390.,Developmental Biology, The University of Texas Southwestern Medical Center, Dallas, Texas, 75390
| | - Hsin-Yi Henry Ho
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, 02115
| | - Michael J Soskis
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, 02115
| | - Michael E Greenberg
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, 02115
| | - Mark Henkemeyer
- Developmental Biology, The University of Texas Southwestern Medical Center, Dallas, Texas, 75390
| | - Christopher W Cowan
- Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, Massachusetts, 02478.,Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, Texas, 75390
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27
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EphB4 forward signalling regulates lymphatic valve development. Nat Commun 2015; 6:6625. [PMID: 25865237 PMCID: PMC4403310 DOI: 10.1038/ncomms7625] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 02/12/2015] [Indexed: 01/08/2023] Open
Abstract
Bidirectional signalling is regarded as a notable hallmark of the Eph-ephrin signalling system: Eph-dependent forward signalling in Eph-expressing cells and ephrin-dependent reverse signalling in Ephrin-expressing cells. The notion of ephrin-dependent reverse signalling derives from genetic experiments utilizing mice carrying mutations in the intracellular region of ephrinBs. Here we show that EphB4-dependent forward signalling regulates lymphatic valve development, a process previously thought to be regulated by ephrinB2-dependent reverse signalling. We develop antibodies that selectively target EphB4 and ephrinB2. We find that mice bearing genetically altered cytoplasmic region of ephrinB2 have significantly altered EphB4-dependent forward signalling. Selective inhibition of EphB4 using a functional blocking antibody results in defective lymphatic valve development. Furthermore, a chemical genetic approach is used to unequivocally show that the kinase activity of EphB4 is essential for lymphatic valve development.
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28
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Affected kindred analysis of human X chromosome exomes to identify novel X-linked intellectual disability genes. PLoS One 2015; 10:e0116454. [PMID: 25679214 PMCID: PMC4332666 DOI: 10.1371/journal.pone.0116454] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 12/08/2014] [Indexed: 12/30/2022] Open
Abstract
X-linked Intellectual Disability (XLID) is a group of genetically heterogeneous disorders caused by mutations in genes on the X chromosome. Deleterious mutations in ~10% of X chromosome genes are implicated in causing XLID disorders in ~50% of known and suspected XLID families. The remaining XLID genes are expected to be rare and even private to individual families. To systematically identify these XLID genes, we sequenced the X chromosome exome (X-exome) in 56 well-established XLID families (a single affected male from 30 families and two affected males from 26 families) using an Agilent SureSelect X-exome kit and the Illumina HiSeq 2000 platform. To enrich for disease-causing mutations, we first utilized variant filters based on dbSNP, the male-restricted portions of the 1000 Genomes Project, or the Exome Variant Server datasets. However, these databases present limitations as automatic filters for enrichment of XLID genes. We therefore developed and optimized a strategy that uses a cohort of affected male kindred pairs and an additional small cohort of affected unrelated males to enrich for potentially pathological variants and to remove neutral variants. This strategy, which we refer to as Affected Kindred/Cross-Cohort Analysis, achieves a substantial enrichment for potentially pathological variants in known XLID genes compared to variant filters from public reference databases, and it has identified novel XLID candidate genes. We conclude that Affected Kindred/Cross-Cohort Analysis can effectively enrich for disease-causing genes in rare, Mendelian disorders, and that public reference databases can be used effectively, but cautiously, as automatic filters for X-linked disorders.
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Park I, Lee HS. EphB/ephrinB signaling in cell adhesion and migration. Mol Cells 2015; 38:14-9. [PMID: 25475547 PMCID: PMC4314128 DOI: 10.14348/molcells.2015.2116] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 10/14/2014] [Accepted: 10/17/2014] [Indexed: 11/27/2022] Open
Abstract
Eph receptors and their ligands, ephrins, represent the largest group of the receptor tyrosine kinase (RTK) family, and they mediate numerous developmental processes in a variety of organisms. Ephrins are membrane-bound proteins that are mainly divided into two classes: A class ephrins, which are linked to the membrane by a glycosylphosphatidylinositol (GPI) linkage, and B class ephrins, which are transmembrane ligands. Based on their domain structures and affinities for ligand binding, the Eph receptors are also divided into two groups. Trans-dimerization of Eph receptors with their membrane-tethered ligands regulates cell-cell interactions and initiates bidirectional signaling pathways. These pathways are intimately involved in regulating cytoskeleton dynamics, cell migration, and alterations in cellular dynamics and shapes. The EphBs and ephrinBs are specifically localized and modified to promote higher-order clustering and initiate of bidirectional signaling. In this review, we present an in-depth overview of the structure, mechanisms, cell signaling, and functions of EphB/ephrinB in cell adhesion and migration.
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Affiliation(s)
- Inji Park
- ABRC, CMRI, School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu 702-701,
Korea
| | - Hyun-Shik Lee
- ABRC, CMRI, School of Life Sciences, BK21 Plus KNU Creative BioResearch Group, Kyungpook National University, Daegu 702-701,
Korea
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30
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Fantauzzo KA, Soriano P. Receptor tyrosine kinase signaling: regulating neural crest development one phosphate at a time. Curr Top Dev Biol 2015; 111:135-82. [PMID: 25662260 PMCID: PMC4363133 DOI: 10.1016/bs.ctdb.2014.11.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Receptor tyrosine kinases (RTKs) bind to a subset of growth factors on the surface of cells and elicit responses with broad roles in developmental and postnatal cellular processes. Receptors in this subclass consist of an extracellular ligand-binding domain, a single transmembrane domain, and an intracellular domain harboring a catalytic tyrosine kinase and regulatory sequences that are phosphorylated either by the receptor itself or by various interacting proteins. Once activated, RTKs bind signaling molecules and recruit effector proteins to mediate downstream cellular responses through various intracellular signaling pathways. In this chapter, we highlight the role of a subset of RTK families in regulating the activity of neural crest cells (NCCs) and the development of their derivatives in mammalian systems. NCCs are migratory, multipotent cells that can be subdivided into four axial populations, cranial, cardiac, vagal, and trunk. These cells migrate throughout the vertebrate embryo along defined pathways and give rise to unique cell types and structures. Interestingly, individual RTK families often have specific functions in a subpopulation of NCCs that contribute to the diversity of these cells and their derivatives in the mammalian embryo. We additionally discuss current methods used to investigate RTK signaling, including genetic, biochemical, large-scale proteomic, and biosensor approaches, which can be applied to study intracellular signaling pathways active downstream of this receptor subclass during NCC development.
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Affiliation(s)
- Katherine A Fantauzzo
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, USA.
| | - Philippe Soriano
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, USA
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31
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McLaughlin T, Lim YS, Santiago A, O'Leary DDM. Multiple EphB receptors mediate dorsal-ventral retinotopic mapping via similar bi-functional responses to ephrin-B1. Mol Cell Neurosci 2014; 63:24-30. [PMID: 25051176 DOI: 10.1016/j.mcn.2014.05.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 05/23/2014] [Indexed: 11/30/2022] Open
Abstract
The projection from the retina to the superior colliculus in mice is organized in a retinotopic map that develops through the formation and guidance of interstitial branches extended by retinal ganglion cell axons. Bidirectional branch guidance along the lateral-medial collicular axis is critical to mapping the dorsal-ventral retinal axis. EphB receptor tyrosine kinases expressed in an overall low to high dorsal-ventral retinal gradient have been implicated in this mapping in response to the graded low to high lateral-medial expression of a ligand, ephrin-B1, in the superior colliculus. However, the relative contributions of EphBs and ephrin-B1 are not well understood. We examined EphB1, EphB2, and EphB3 mutant mice and find that each has ectopic arborizations of retinal axon branches lateral to their appropriate termination zone, with no qualitative differences in aberrant mapping, suggesting a similar role for each EphB. However, the frequency of cases with map defects progressively rises in compound EphB mutants coincident with the number of EphB null alleles from one to five of the six total alleles indicating that EphB level is critical. We analyzed branch extension in vitro and find that dorsal branches, with low EphB levels, exhibit a negative response to ephrin-B1, whereas ventral branches, with high EphB levels, exhibit a positive response to ephrin-B1. Using EphB mutant retina, we show that both of these differential branch extension responses are dependent on EphB level. Our findings show a bifunctional action of ephrin-B1 regulated by EphB levels that can account for the bidirectional extension of interstitial branches required to establish a retinotopic map.
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Affiliation(s)
- Todd McLaughlin
- Molecular Neurobiology Laboratory, The Salk Institute, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Yoo-Shick Lim
- Molecular Neurobiology Laboratory, The Salk Institute, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Alicia Santiago
- Molecular Neurobiology Laboratory, The Salk Institute, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Dennis D M O'Leary
- Molecular Neurobiology Laboratory, The Salk Institute, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA.
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32
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Conte I, Merella S, Garcia-Manteiga JM, Migliore C, Lazarevic D, Carrella S, Marco-Ferreres R, Avellino R, Davidson NP, Emmett W, Sanges R, Bockett N, Van Heel D, Meroni G, Bovolenta P, Stupka E, Banfi S. The combination of transcriptomics and informatics identifies pathways targeted by miR-204 during neurogenesis and axon guidance. Nucleic Acids Res 2014; 42:7793-806. [PMID: 24895435 PMCID: PMC4081098 DOI: 10.1093/nar/gku498] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Vertebrate organogenesis is critically sensitive to gene dosage and even subtle variations in the expression levels of key genes may result in a variety of tissue anomalies. MicroRNAs (miRNAs) are fundamental regulators of gene expression and their role in vertebrate tissue patterning is just beginning to be elucidated. To gain further insight into this issue, we analysed the transcriptomic consequences of manipulating the expression of miR-204 in the Medaka fish model system. We used RNA-Seq and an innovative bioinformatics approach, which combines conventional differential expression analysis with the behavior expected by miR-204 targets after its overexpression and knockdown. With this approach combined with a correlative analysis of the putative targets, we identified a wider set of miR-204 target genes belonging to different pathways. Together, these approaches confirmed that miR-204 has a key role in eye development and further highlighted its putative function in neural differentiation processes, including axon guidance as supported by in vivo functional studies. Together, our results demonstrate the advantage of integrating next-generation sequencing and bioinformatics approaches to investigate miRNA biology and provide new important information on the role of miRNAs in the control of axon guidance and more broadly in nervous system development.
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Affiliation(s)
- Ivan Conte
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino, 111, 80131 Naples, Italy
| | - Stefania Merella
- Center For Translational Genomics and Bioinformatics, San Raffaele Scientific Institute, Via Olgettina, 58, 20132 Milan, Italy
| | - Jose Manuel Garcia-Manteiga
- Center For Translational Genomics and Bioinformatics, San Raffaele Scientific Institute, Via Olgettina, 58, 20132 Milan, Italy
| | - Chiara Migliore
- CBM Scrl, c/o Area Science Park, Basovizza, 30143 Trieste, Italy
| | - Dejan Lazarevic
- Center For Translational Genomics and Bioinformatics, San Raffaele Scientific Institute, Via Olgettina, 58, 20132 Milan, Italy
| | - Sabrina Carrella
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino, 111, 80131 Naples, Italy
| | - Raquel Marco-Ferreres
- Centro de Biología Molecular 'Severo Ochoa', CSIC-UAM, c/Nicolas Cabrera 1, Madrid 28049, Spain CIBER de Enfermedades Raras (CIBERER), c/ Nicolas Cabrera 1, Madrid 28049, Spain
| | - Raffaella Avellino
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino, 111, 80131 Naples, Italy
| | - Nathan Paul Davidson
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino, 111, 80131 Naples, Italy
| | - Warren Emmett
- UCL Cancer Institute, Huntley Street, University College London, London WC1E 6BT, UK
| | - Remo Sanges
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Napoli, Italy
| | - Nicholas Bockett
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - David Van Heel
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 2AT, UK
| | - Germana Meroni
- CBM Scrl, c/o Area Science Park, Basovizza, 30143 Trieste, Italy
| | - Paola Bovolenta
- Centro de Biología Molecular 'Severo Ochoa', CSIC-UAM, c/Nicolas Cabrera 1, Madrid 28049, Spain CIBER de Enfermedades Raras (CIBERER), c/ Nicolas Cabrera 1, Madrid 28049, Spain
| | - Elia Stupka
- Center For Translational Genomics and Bioinformatics, San Raffaele Scientific Institute, Via Olgettina, 58, 20132 Milan, Italy
| | - Sandro Banfi
- Telethon Institute of Genetics and Medicine, Via Pietro Castellino, 111, 80131 Naples, Italy Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, 80138 Naples, Italy
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Lucchese G, Capone G, Kanduc D. Peptide sharing between influenza A H1N1 hemagglutinin and human axon guidance proteins. Schizophr Bull 2014; 40:362-75. [PMID: 23378012 PMCID: PMC3932078 DOI: 10.1093/schbul/sbs197] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Epidemiologic data suggest that maternal microbial infections may cause fetal neurodevelopmental disorders, potentially increasing susceptibility to heavy psychopathologies such as schizophrenia, schizophreniform disorder, autism, pervasive developmental disorders, bipolar disorders, psychosis, epilepsy, language and speech disorders, and cognitive impairment in adult offspring. However, the molecular pathomechanisms underlying such a relationship are not clear. Here we analyze the potential role of the maternal immune response to viral infection in determining fetal brain injuries that increase the risk of neurological disorders in the adult. We use influenza infection as a disease model and human axon guidance pathway, a key process in the formation of neural network during midgestation, as a potential fetal target of immune insults. Specifically, we examined influenza A H1N1 hemagglutinin (HA), an antigenic viral protein, for amino acid sequence similarity to a random library of 188 axon guidance proteins. We obtain the results that (1) contrary to any theoretical expectations, 45 viral pentapeptide matches are distributed throughout a subset of 36 guidance molecules; (2) in 24 guidance proteins, the peptide sharing with HA antigen involves already experimentally validated influenza HA epitopes; and (3) most of the axon guidance vs HA peptide overlap is conserved among influenza A viral strains and subsets. Taken together, our data indicate that immune cross-reactivity between influenza HA and axon guidance molecules is possible and may well represent a pathologic mechanism capable of determining neurodevelopmental disruption in the fetus.
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Affiliation(s)
- Guglielmo Lucchese
- To whom correspondence should be addressed; tel: +39.080.544.3321, fax: +39.080.544.3317, e-mail:
| | - Giovanni Capone
- Department of Biosciences, Biotechnologies and Pharmacological Sciences, University of Bari, Bari, Italy
| | - Darja Kanduc
- Department of Biosciences, Biotechnologies and Pharmacological Sciences, University of Bari, Bari, Italy,To whom correspondence should be addressed; tel: +39.080.544.3321, fax: +39.080.544.3317, e-mail:
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34
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Cortical abnormalities and non-spatial learning deficits in a mouse model of CranioFrontoNasal syndrome. PLoS One 2014; 9:e88325. [PMID: 24520368 PMCID: PMC3919725 DOI: 10.1371/journal.pone.0088325] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 01/07/2014] [Indexed: 11/22/2022] Open
Abstract
Eph receptors and their ephrin ligands play critical roles in the development of the nervous system, however, less is known about their functions in the adult brain. Here, we investigated the function of ephrinB1, an ephrinB family member that is mutated in CranioFrontoNasal Syndrome. We show that ephrinB1 deficient mice (EfnB1Y/−) demonstrate spared spatial learning and memory but exhibit exclusive impairment in non-spatial learning and memory tasks. We established that ephrinB1 does not control learning and memory through direct modulation of synaptic plasticity in adults, since it is not expressed in the adult brain. Rather we show that the cortex of EfnB1Y/− mice displayed supernumerary neurons, with a particular increase in calretinin-positive interneurons. Further, the increased neuron number in EfnB1Y/− mutants correlated with shorter dendritic arborization and decreased spine densities of cortical pyramidal neurons. Our findings indicate that ephrinB1 plays an important role in cortical maturation and that its loss has deleterious consequences on selective cognitive functions in the adult.
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36
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Lisabeth EM, Falivelli G, Pasquale EB. Eph receptor signaling and ephrins. Cold Spring Harb Perspect Biol 2013; 5:5/9/a009159. [PMID: 24003208 DOI: 10.1101/cshperspect.a009159] [Citation(s) in RCA: 292] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Eph receptors are the largest of the RTK families. Like other RTKs, they transduce signals from the cell exterior to the interior through ligand-induced activation of their kinase domain. However, the Eph receptors also have distinctive features. Instead of binding soluble ligands, they generally mediate contact-dependent cell-cell communication by interacting with surface-associated ligands-the ephrins-on neighboring cells. Eph receptor-ephrin complexes emanate bidirectional signals that affect both receptor- and ephrin-expressing cells. Intriguingly, ephrins can also attenuate signaling by Eph receptors coexpressed in the same cell. Additionally, Eph receptors can modulate cell behavior independently of ephrin binding and kinase activity. The Eph/ephrin system regulates many developmental processes and adult tissue homeostasis. Its abnormal function has been implicated in various diseases, including cancer. Thus, Eph receptors represent promising therapeutic targets. However, more research is needed to better understand the many aspects of their complex biology that remain mysterious.
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Affiliation(s)
- Erika M Lisabeth
- Cancer Center, Sanford-Burnham Medical Research Institute, La Jolla, California 92037, USA
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37
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Niquille M, Minocha S, Hornung JP, Rufer N, Valloton D, Kessaris N, Alfonsi F, Vitalis T, Yanagawa Y, Devenoges C, Dayer A, Lebrand C. Two specific populations of GABAergic neurons originating from the medial and the caudal ganglionic eminences aid in proper navigation of callosal axons. Dev Neurobiol 2013; 73:647-72. [PMID: 23420573 DOI: 10.1002/dneu.22075] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 02/10/2013] [Accepted: 02/11/2013] [Indexed: 12/22/2022]
Abstract
The corpus callosum (CC) plays a crucial role in interhemispheric communication. It has been shown that CC formation relies on the guidepost cells located in the midline region that include glutamatergic and GABAergic neurons as well as glial cells. However, the origin of these guidepost GABAergic neurons and their precise function in callosal axon pathfinding remain to be investigated. Here, we show that two distinct GABAergic neuronal subpopulations converge toward the midline prior to the arrival of callosal axons. Using in vivo and ex vivo fate mapping we show that CC GABAergic neurons originate in the caudal and medial ganglionic eminences (CGE and MGE) but not in the lateral ganglionic eminence (LGE). Time lapse imaging on organotypic slices and in vivo analyses further revealed that CC GABAergic neurons contribute to the normal navigation of callosal axons. The use of Nkx2.1 knockout (KO) mice confirmed a role of these neurons in the maintenance of proper behavior of callosal axons while growing through the CC. Indeed, using in vitro transplantation assays, we demonstrated that both MGE- and CGE-derived GABAergic neurons exert an attractive activity on callosal axons. Furthermore, by combining a sensitive RT-PCR technique with in situ hybridization, we demonstrate that CC neurons express multiple short and long range guidance cues. This study strongly suggests that MGE- and CGE-derived interneurons may guide CC axons by multiple guidance mechanisms and signaling pathways.
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Affiliation(s)
- Mathieu Niquille
- Département des neurosciences fondamentales, University of Lausanne, Rue du Bugnon 9, CH-1005 Lausanne, Switzerland
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A sympathetic neuron autonomous role for Egr3-mediated gene regulation in dendrite morphogenesis and target tissue innervation. J Neurosci 2013; 33:4570-83. [PMID: 23467373 DOI: 10.1523/jneurosci.5481-12.2013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Egr3 is a nerve growth factor (NGF)-induced transcriptional regulator that is essential for normal sympathetic nervous system development. Mice lacking Egr3 in the germline have sympathetic target tissue innervation abnormalities and physiologic sympathetic dysfunction similar to humans with dysautonomia. However, since Egr3 is widely expressed and has pleiotropic function, it has not been clear whether it has a role within sympathetic neurons and if so, what target genes it regulates to facilitate target tissue innervation. Here, we show that Egr3 expression within sympathetic neurons is required for their normal innervation since isolated sympathetic neurons lacking Egr3 have neurite outgrowth abnormalities when treated with NGF and mice with sympathetic neuron-restricted Egr3 ablation have target tissue innervation abnormalities similar to mice lacking Egr3 in all tissues. Microarray analysis performed on sympathetic neurons identified many target genes deregulated in the absence of Egr3, with some of the most significantly deregulated genes having roles in axonogenesis, dendritogenesis, and axon guidance. Using a novel genetic technique to visualize axons and dendrites in a subpopulation of randomly labeled sympathetic neurons, we found that Egr3 has an essential role in regulating sympathetic neuron dendrite morphology and terminal axon branching, but not in regulating sympathetic axon guidance to their targets. Together, these results indicate that Egr3 has a sympathetic neuron autonomous role in sympathetic nervous system development that involves modulating downstream target genes affecting the outgrowth and branching of sympathetic neuron dendrites and axons.
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Arvanitis DN, Béhar A, Tryoen-Tóth P, Bush JO, Jungas T, Vitale N, Davy A. Ephrin B1 maintains apical adhesion of neural progenitors. Development 2013; 140:2082-92. [PMID: 23578932 DOI: 10.1242/dev.088203] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Apical neural progenitors are polarized cells for which the apical membrane is the site of cell-cell and cell-extracellular matrix adhesion events that are essential for maintaining the integrity of the developing neuroepithelium. Apical adhesion is important for several aspects of the nervous system development, including morphogenesis and neurogenesis, yet the mechanisms underlying its regulation remain poorly understood. Here, we show that ephrin B1, a cell surface protein that engages in cell signaling upon binding cognate Eph receptors, controls normal morphogenesis of the developing cortex. Efnb1-deficient embryos exhibit morphological alterations of the neuroepithelium that correlate with neural tube closure defects. Using loss-of-function experiments by ex vivo electroporation, we demonstrate that ephrin B1 is required in apical progenitors (APs) to maintain their apical adhesion. Mechanistically, we show that ephrin B1 controls cell-ECM adhesion by promoting apical localization of integrin β1 and we identify ADP-ribosylation factor 6 (Arf6) as an important effector of ephrin B1 reverse signaling in apical adhesion of APs. Our results provide evidence for an important role for ephrin B1 in maintaining the structural integrity of the developing cortex and highlight the importance of tightly controlling apical cell-ECM adhesion for neuroepithelial development.
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Affiliation(s)
- Dina N Arvanitis
- Centre de Biologie du Développement, CNRS, 118 Route de Narbonne, Bât 4R3, 31062 Toulouse cedex 9, France
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Axon guidance mechanisms for establishment of callosal connections. Neural Plast 2013; 2013:149060. [PMID: 23533817 PMCID: PMC3595665 DOI: 10.1155/2013/149060] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Revised: 12/30/2012] [Accepted: 01/21/2013] [Indexed: 01/03/2023] Open
Abstract
Numerous studies have investigated the formation of interhemispheric connections which are involved in high-ordered functions of the cerebral cortex in eutherian animals, including humans. The development of callosal axons, which transfer and integrate information between the right/left hemispheres and represent the most prominent commissural system, must be strictly regulated. From the beginning of their growth, until reaching their targets in the contralateral cortex, the callosal axons are guided mainly by two environmental cues: (1) the midline structures and (2) neighboring? axons. Recent studies have shown the importance of axona guidance by such cues and the underlying molecular mechanisms. In this paper, we review these guidance mechanisms during the development of the callosal neurons. Midline populations express and secrete guidance molecules, and "pioneer" axons as well as interactions between the medial and lateral axons are also involved in the axon pathfinding of the callosal neurons. Finally, we describe callosal dysgenesis in humans and mice, that results from a disruption of these navigational mechanisms.
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Abstract
Eph receptors and their membrane-tethered ligands have important functions in development. Trans interactions of Eph receptors with ephrins at cell-cell interfaces promote a variety of cellular responses, including repulsion, attraction and migration. Eph-ephrin signalling can be bi-directional and controls actin cytoskeleton dynamics, thereby leading to changes in cellular shape. This article provides an overview of the general structures and signalling mechanisms, and of typical developmental functions along with cell biological principles.
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Affiliation(s)
- Rüdiger Klein
- Max-Planck Institute of Neurobiology, Department of Molecular Neurobiology, Am Klopferspitz 18, Munich-Martinsried, Germany.
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Dhanasobhon D, Savier E, Lelievre V. To phosphorylate or not to phosphorylate: Selective alterations in tyrosine kinase-inhibited EphB mutant mice. Cell Adh Migr 2013; 8:1-4. [PMID: 24589619 DOI: 10.4161/cam.27478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
EphB tyrosine kinase receptors have been implicated in multiple developmental processes; however, the signaling mechanism underlying these events remains unclear. Through a triple knock-in mouse line for three neurally expressed EphBs, Sokis et al. demonstrated that EphB tyrosine kinase activity is required for axon guidance but does not influence synapse formation. This short communication highlights their study and appealing molecular approach that elucidated the functions of EphB tyrosine kinase during developmental events.
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Affiliation(s)
- Dhanasak Dhanasobhon
- Joint master in Neuroscience; University of Strasbourg-France; Strasbourg, France
| | - Elise Savier
- Joint master in Neuroscience; University of Strasbourg-France; Strasbourg, France
| | - Vincent Lelievre
- Joint master in Neuroscience; University of Strasbourg-France; Strasbourg, France
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A chemical genetic approach reveals distinct EphB signaling mechanisms during brain development. Nat Neurosci 2012; 15:1645-54. [PMID: 23143520 PMCID: PMC3509236 DOI: 10.1038/nn.3249] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 10/01/2012] [Indexed: 12/15/2022]
Abstract
EphB receptor tyrosine kinases control multiple steps in nervous system development. However, it remains unclear whether EphBs regulate these different developmental processes directly or indirectly. In addition, as EphBs signal through multiple mechanisms, it has been challenging to define which signaling functions of EphBs regulate particular developmental events. To address these issues, we engineered triple knockin mice in which the kinase activity of three neuronally expressed EphBs can be rapidly, reversibly, and specifically blocked. Using these mice we demonstrate that the tyrosine kinase activity of EphBs is required for axon guidance in vivo. By contrast, EphB-mediated synaptogenesis occurs normally when the kinase activity of EphBs is inhibited suggesting that EphBs mediate synapse development by an EphB tyrosine kinase-independent mechanism. Taken together, these experiments reveal that EphBs control axon guidance and synaptogenesis by distinct mechanisms, and provide a new mouse model for dissecting EphB function in development and disease.
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Sikkema AH, den Dunnen WF, Hulleman E, van Vuurden DG, Garcia-Manero G, Yang H, Scherpen FJ, Kampen KR, Hoving EW, Kamps WA, Diks SH, Peppelenbosch MP, de Bont ES. EphB2 activity plays a pivotal role in pediatric medulloblastoma cell adhesion and invasion. Neuro Oncol 2012; 14:1125-35. [PMID: 22723427 PMCID: PMC3424207 DOI: 10.1093/neuonc/nos130] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 04/25/2012] [Indexed: 01/05/2023] Open
Abstract
Eph/ephrin signaling has been implicated in various types of key cancer-enhancing processes, like migration, proliferation, and angiogenesis. In medulloblastoma, invading tumor cells characteristically lead to early recurrence and a decreased prognosis. Based on kinase-activity profiling data published recently, we hypothesized a key role for the Eph/ephrin signaling system in medulloblastoma invasion. In primary medulloblastoma samples, a significantly higher expression of EphB2 and the ligand ephrin-B1 was observed compared with normal cerebellum. Furthermore, medulloblastoma cell lines showed high expression of EphA2, EphB2, and EphB4. Stimulation of medulloblastoma cells with ephrin-B1 resulted in a marked decrease in in vitro cell adhesion and an increase in the invasion capacity of cells expressing high levels of EphB2. The cell lines that showed an ephrin-B1-induced phenotype possessed increased levels of phosphorylated EphB2 and, to a lesser extent, EphB4 after stimulation. Knockdown of EphB2 expression by short hairpin RNA completely abolished ephrin ligand-induced effects on adhesion and migration. Analysis of signal transduction identified p38, Erk, and mTOR as downstream signaling mediators potentially inducing the ephrin-B1 phenotype. In conclusion, the observed deregulation of Eph/ephrin expression in medulloblastoma enhances the invasive phenotype, suggesting a potential role in local tumor cell invasion and the formation of metastases.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Eveline S.J.M. de Bont
- Department of Pediatric Oncology/Hematology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, Groningen, the Netherlands (A.H.S., F.J.G.S., K.R.K., W.A.K., S.H.D., E.S.J.M.B.); Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, Groningen, the Netherlands (W.F.A.D.); Neuro-Oncology Research Group, Cancer Center Amsterdam, VU University Medical Center, De Boelelaan 1117, Amsterdam, the Netherlands (E.H., D.G.V.); Department of Leukemia, Division of Cancer Medicine, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas, USA (G.G.-M., H.Y.); Department of Neurosurgery, University Medical Center Groningen, Hanzeplein 1, Groningen, the Netherlands (E.W.H.); Department of Gastroenterology and Hepatology, Erasmus MC, L-459, 's-Gravendijkwal 230, Rotterdam, the Netherlands (M.P.P.)
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The role of vertebrate models in understanding craniosynostosis. Childs Nerv Syst 2012; 28:1471-81. [PMID: 22872264 DOI: 10.1007/s00381-012-1844-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 06/13/2012] [Indexed: 01/10/2023]
Abstract
BACKGROUND Craniosynostosis (CS), the premature fusion of cranial sutures, is a relatively common pediatric anomaly, occurring in isolation or as part of a syndrome. A growing number of genes with pathologic mutations have been identified for syndromic and nonsyndromic CS. The study of human sutural material obtained post-operatively is not sufficient to understand the etiology of CS, for which animal models are indispensable. DISCUSSION The similarity of the human and murine calvarial structure, our knowledge of mouse genetics and biology, and ability to manipulate the mouse genome make the mouse the most valuable model organism for CS research. A variety of mouse mutants are available that model specific human CS mutations or have CS phenotypes. These allow characterization of the biochemical and morphological events, often embryonic, which precede suture fusion. Other vertebrate organisms have less functional genetic utility than mice, but the rat, rabbit, chick, zebrafish, and frog provide alternative systems in which to validate or contrast molecular functions relevant to CS.
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Nievergall E, Lackmann M, Janes PW. Eph-dependent cell-cell adhesion and segregation in development and cancer. Cell Mol Life Sci 2012; 69:1813-42. [PMID: 22204021 PMCID: PMC11114713 DOI: 10.1007/s00018-011-0900-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/06/2011] [Accepted: 11/28/2011] [Indexed: 01/23/2023]
Abstract
Numerous studies attest to essential roles for Eph receptors and their ephrin ligands in controlling cell positioning and tissue patterning during normal and oncogenic development. These studies suggest multiple, sometimes contradictory, functions of Eph-ephrin signalling, which under different conditions can promote either spreading and cell-cell adhesion or cytoskeletal collapse, cell rounding, de-adhesion and cell-cell segregation. A principle determinant of the balance between these two opposing responses is the degree of receptor/ligand clustering and activation. This equilibrium is likely altered in cancers and modulated by somatic mutations of key Eph family members that have emerged as candidate cancer markers in recent profiling studies. In addition, cross-talk amongst Ephs and with other signalling pathways significantly modulates cell-cell adhesion, both between and within Eph- and ephrin-expressing cell populations. This review summarises our current understanding of how Eph receptors control cell adhesion and morphology, and presents examples demonstrating the importance of these events in normal development and cancer.
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Affiliation(s)
- Eva Nievergall
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
- Present Address: Haematology Department, SA Pathology, Frome Road, Adelaide, SA 5000 Australia
| | - Martin Lackmann
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
| | - Peter W. Janes
- Department of Biochemistry and Molecular Biology, Monash University, Wellington Road, Clayton, VIC 3800 Australia
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Walsh R, Blumenberg M. Eph-2B, acting as an extracellular ligand, induces differentiation markers in epidermal keratinocytes. J Cell Physiol 2012; 227:2330-40. [PMID: 21809346 DOI: 10.1002/jcp.22968] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
In the bi-directional signaling system comprising ephrins (EFNs) and ephrin receptors (Ephs), both EFNs and Ephs simultaneously function both as ligands and as receptors. Importantly, the EFN/Eph system is deregulated in human cancers and has been implicated in the metastatic processes because of its effects on the adhesion and migration of epithelial cells. The idiosyncratic function of Ephs, membrane-bound receptor kinases, as extracellular signaling ligands, has not been extensively studied. This prompted us to explore the transcriptional targets regulated by Ephs acting solely as ligands. To define the ligand function of EphB2 in human epidermal keratinocytes, we treated these cells with EphB2 as Fc-conjugate dimmers, which thus act exclusively as extracellular ligands. We compared the EphB2 and EFNA4 effects during a 48 h time course, using transcriptional profiling. We found that EphB2, acting as a ligand, promotes epidermal differentiation. For example, EphB2 induces expression of markers of epidermal differentiation, including keratins KRT1 and KRT10, SPRRs, desmosomal proteins and cell cycle inhibitors, while suppressing basal layer markers, integrins and cell cycle proteins. The effects of EphB2 are delayed relative to those of EFNA4. Unlike EFNA4, EphB2 did not induce lipid metabolism proteins, this particular aspect of epidermal differentiation seems not to be regulated by EphB2. Our results define the transcriptional targets of the reverse signaling by EphB2 acting exclusively as a ligand and begin to characterize this intriguing function of Ephs.
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Affiliation(s)
- Rebecca Walsh
- The Department of Dermatology, NYU Cancer Institute, NYU School of Medicine, New York 10016, USA
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Stevenson TJ, Trinh T, Kogelschatz C, Fujimoto E, Lush ME, Piotrowski T, Brimley CJ, Bonkowsky JL. Hypoxia disruption of vertebrate CNS pathfinding through ephrinB2 Is rescued by magnesium. PLoS Genet 2012; 8:e1002638. [PMID: 22511881 PMCID: PMC3325188 DOI: 10.1371/journal.pgen.1002638] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 02/21/2012] [Indexed: 11/19/2022] Open
Abstract
The mechanisms of hypoxic injury to the developing human brain are poorly understood, despite being a major cause of chronic neurodevelopmental impairments. Recent work in the invertebrate Caenorhabditis elegans has shown that hypoxia causes discrete axon pathfinding errors in certain interneurons and motorneurons. However, it is unknown whether developmental hypoxia would have similar effects in a vertebrate nervous system. We have found that developmental hypoxic injury disrupts pathfinding of forebrain neurons in zebrafish (Danio rerio), leading to errors in which commissural axons fail to cross the midline. The pathfinding defects result from activation of the hypoxia-inducible transcription factor (hif1) pathway and are mimicked by chemical inducers of the hif1 pathway or by expression of constitutively active hif1α. Further, we found that blocking transcriptional activation by hif1α helped prevent the guidance defects. We identified ephrinB2a as a target of hif1 pathway activation, showed that knock-down of ephrinB2a rescued the guidance errors, and showed that the receptor ephA4a is expressed in a pattern complementary to the misrouting axons. By targeting a constitutively active form of ephrinB2a to specific neurons, we found that ephrinB2a mediates the pathfinding errors via a reverse-signaling mechanism. Finally, magnesium sulfate, used to improve neurodevelopmental outcomes in preterm births, protects against pathfinding errors by preventing upregulation of ephrinB2a. These results demonstrate that evolutionarily conserved genetic pathways regulate connectivity changes in the CNS in response to hypoxia, and they support a potential neuroprotective role for magnesium. How hypoxia damages the developing human brain is poorly understood, despite being a major cause of life-long neurologic and psychiatric problems. Premature infants are especially at risk for these problems, with increased rates of attention-deficit disorder, autism, cerebral palsy, epilepsy, psychiatric disorders, and cognitive impairment. It is unknown whether hypoxia can cause errors in the connections of neurons in the vertebrate nervous system. We used zebrafish, a vertebrate model animal, to answer this question. We found that hypoxic injury causes errors in how neurons connect. We went on to determine that a specific genetic pathway, the hif1 pathway, is activated by hypoxia and turns on downstream genes, which cause the connection problems. One of the genes activated by hif1, ephrinB2a, is responsible for many of the connection problems. Importantly, magnesium, used as a treatment for some preterm births, is able to help protect against the neuron connection errors. Our results show that hypoxia in vertebrates does cause errors in neuron connections and that magnesium can help prevent this.
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Affiliation(s)
- Tamara J. Stevenson
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Tony Trinh
- University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Cory Kogelschatz
- University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Esther Fujimoto
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Mark E. Lush
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Tatjana Piotrowski
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Cameron J. Brimley
- University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Joshua L. Bonkowsky
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- * E-mail:
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Rodger J, Salvatore L, Migani P. Should I stay or should I go? Ephs and ephrins in neuronal migration. Neurosignals 2012; 20:190-201. [PMID: 22456188 DOI: 10.1159/000333784] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In neuroscience, Ephs and ephrins are perhaps best known for their role in axon guidance. It was first shown in the visual system that graded expression of these proteins is instrumental in providing molecular coordinates that define topographic maps, particularly in the visual system, but also in the auditory, vomeronasal and somatosensory systems as well as in the hippocampus, cerebellum and other structures. Perhaps unsurprisingly, the role of these proteins in regulating cell-cell interactions also has an impact on cell mobility, with evidence that Eph-ephrin interactions segregate cell populations based on contact-mediated attraction or repulsion. Consistent with these studies, evidence has accumulated that Ephs and ephrins play important roles in the migration of specific cell populations in the developing and adult brain. This review focusses on two examples of neuronal migration that require Eph/ephrin signalling - radial and tangential migration of neurons in cortical development and the migration of newly generated neurons along the rostral migratory stream to the olfactory bulb in the adult brain. We discuss the challenge involved in understanding how cells determine whether they respond to signals by migration or axon guidance.
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Affiliation(s)
- Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Animal Biology M317, University of Western Australia, Crawley, WA, Australia
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Bush JO, Jiang R. Palatogenesis: morphogenetic and molecular mechanisms of secondary palate development. Development 2012; 139:231-43. [PMID: 22186724 DOI: 10.1242/dev.067082] [Citation(s) in RCA: 358] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Mammalian palatogenesis is a highly regulated morphogenetic process during which the embryonic primary and secondary palatal shelves develop as outgrowths from the medial nasal and maxillary prominences, respectively, remodel and fuse to form the intact roof of the oral cavity. The complexity of control of palatogenesis is reflected by the common occurrence of cleft palate in humans. Although the embryology of the palate has long been studied, the past decade has brought substantial new knowledge of the genetic control of secondary palate development. Here, we review major advances in the understanding of the morphogenetic and molecular mechanisms controlling palatal shelf growth, elevation, adhesion and fusion, and palatal bone formation.
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Affiliation(s)
- Jeffrey O Bush
- Department of Cell and Tissue Biology and Program in Craniofacial and Mesenchymal Biology, University of California at San Francisco, San Francisco, CA 94143, USA.
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