1
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Dai L, Huang J, Shen KF, Yang XL, Zhu G, Zhang L, Wang ZK, Liu SY, Liao X, Xu SL, Yang H, Li XY, Zhang CQ. Altered expression of the Plexin-B2 system in tuberous sclerosis complex and focal cortical dysplasia IIb lesions. Histol Histopathol 2024; 39:1179-1195. [PMID: 38293776 DOI: 10.14670/hh-18-707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD) type IIb are the predominant causes of drug-refractory epilepsy in children. Dysmorphic neurons (DNs), giant cells (GCs), and balloon cells (BCs) are the most typical pathogenic profiles in cortical lesions of TSC and FCD IIb patients. However, mechanisms underlying the pathological processes of TSC and FCD IIb remain obscure. The Plexin-B2-Sema4C signalling pathway plays critical roles in neuronal morphogenesis and corticogenesis during the development of the central nervous system. However, the role of the Plexin-B2 system in the pathogenic process of TSC and FCD IIb has not been identified. In the present study, we investigated the expression and cell distribution characteristics of Plexin-B2 and Sema4C in TSC and FCD IIb lesions with molecular technologies. Our results showed that the mRNA and protein levels of Plexin-B2 expression were significantly increased both in TSC and FCD IIb lesions versus that in the control cortex. Notably, Plexin-B2 was also predominantly observed in GCs in TSC epileptic lesions and BCs in FCD IIb lesions. In contrast, the expression of Sema4C, the ligand of Plexin-B2, was significantly decreased in DNs, GCs, and BCs in TSC and FCD IIb epileptic lesions. Additionally, Plexin-B2 and Sema4C were expressed in astrocytes and microglia cells in TSC and FCD IIb lesions. Furthermore, the expression of Plexin-B2 was positively correlated with seizure frequency in TSC and FCD IIb patients. In conclusion, our results showed the Plexin-B2-Sema4C system was abnormally expressed in cortical lesions of TSC and FCD IIb patients, signifying that the Plexin-B2-Sema4C system may play a role in the pathogenic development of TSC and FCD IIb.
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Affiliation(s)
- Lu Dai
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
| | - Jun Huang
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
| | - Kai-Feng Shen
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
| | - Xiao-Lin Yang
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
| | - Gang Zhu
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
| | - Li Zhang
- Department of Pediatric Neurosurgery, Ministry of Education Key Laboratory of Child Development and Disorders, National Clinical Research Center for Child Health and Disorders, China International Science and Technology Cooperation base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing Key Laboratory of Pediatrics, Chongqing, PR China
| | - Zhong-Ke Wang
- Department of Neurosurgery, Armed Police Hospital of Chongqing, Chongqing, PR China
| | - Shi-Yong Liu
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
| | - Xiang Liao
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing, PR China
| | - Sen-Lin Xu
- Institute of Pathology, Southwest Hospital, Chongqing, PR China
| | - Hui Yang
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China
- Chongqing Institute for Brain and Intelligence, Guangyang Bay Laboratory, Chongqing, PR China
| | - Xing-Yi Li
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing, PR China.
| | - Chun-Qing Zhang
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, PR China.
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2
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Dai L, Shen KF, Zhang CQ. Plexin-mediated neuronal development and neuroinflammatory responses in the nervous system. Histol Histopathol 2023; 38:1239-1248. [PMID: 37170703 DOI: 10.14670/hh-18-625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Plexins are a large family of single-pass transmembrane proteins that mediate semaphorin signaling in multiple systems. Plexins were originally characterized for their role modulating cytoskeletal activity to regulate axon guidance during nervous system development. Thereafter, different semaphorin-plexin complexes were identified in the nervous system that have diverse functions in neurons, astrocytes, glia, oligodendrocytes, and brain derived-tumor cells, providing unexpected but meaningful insights into the biological activities of this protein family. Here, we review the overall structure and relevant downstream signaling cascades of plexins. We consider the current knowledge regarding the function of semaphorin-plexin cascades in the nervous system, including the most recent data regarding their roles in neuronal development, neuroinflammation, and glioma.
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Affiliation(s)
- Lu Dai
- Center for Neurointelligence, School of Medicine, Chongqing University, Chongqing, China
| | - Kai-Feng Shen
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Chun-Qing Zhang
- Department of Neurosurgery, Epilepsy Research Center of PLA, Xinqiao Hospital, Army Medical University, Chongqing, China.
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3
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Gerstmann K, Kindbeiter K, Telley L, Bozon M, Reynaud F, Théoulle E, Charoy C, Jabaudon D, Moret F, Castellani V. A balance of noncanonical Semaphorin signaling from the cerebrospinal fluid regulates apical cell dynamics during corticogenesis. SCIENCE ADVANCES 2022; 8:eabo4552. [PMID: 36399562 PMCID: PMC9674300 DOI: 10.1126/sciadv.abo4552] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 10/03/2022] [Indexed: 06/01/2023]
Abstract
During corticogenesis, dynamic regulation of apical adhesion is fundamental to generate correct numbers and cell identities. While radial glial cells (RGCs) maintain basal and apical anchors, basal progenitors and neurons detach and settle at distal positions from the apical border. Whether diffusible signals delivered from the cerebrospinal fluid (CSF) contribute to the regulation of apical adhesion dynamics remains fully unknown. Secreted class 3 Semaphorins (Semas) trigger cell responses via Plexin-Neuropilin (Nrp) membrane receptor complexes. Here, we report that unconventional Sema3-Nrp preformed complexes are delivered by the CSF from sources including the choroid plexus to Plexin-expressing RGCs via their apical endfeet. Through analysis of mutant mouse models and various ex vivo assays mimicking ventricular delivery to RGCs, we found that two different complexes, Sema3B/Nrp2 and Sema3F/Nrp1, exert dual effects on apical endfeet dynamics, nuclei positioning, and RGC progeny. This reveals unexpected balance of CSF-delivered guidance molecules during cortical development.
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Affiliation(s)
- Katrin Gerstmann
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
| | - Karine Kindbeiter
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
| | - Ludovic Telley
- Department of Basic Neuroscience, University of Geneva, 1211 Geneva 4, Switzerland
| | - Muriel Bozon
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
| | - Florie Reynaud
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
| | - Emy Théoulle
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
| | - Camille Charoy
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Denis Jabaudon
- Department of Basic Neuroscience, University of Geneva, 1211 Geneva 4, Switzerland
| | - Frédéric Moret
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
| | - Valerie Castellani
- MeLis, CNRS UMR 5284, INSERM U1314, University of Lyon, Université Claude Bernard Lyon 1, Institut NeuroMyoGène, 8 avenue Rockefeller, 69008 Lyon, France
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4
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Murakami T, Takahata Y, Hata K, Ebina K, Hirose K, Ruengsinpinya L, Nakaminami Y, Etani Y, Kobayashi S, Maruyama T, Nakano H, Kaneko T, Toyosawa S, Asahara H, Nishimura R. Semaphorin 4D induces articular cartilage destruction and inflammation in joints by transcriptionally reprogramming chondrocytes. Sci Signal 2022; 15:eabl5304. [PMID: 36318619 DOI: 10.1126/scisignal.abl5304] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Proinflammatory cytokines play critical roles in the pathogenesis of joint diseases. Using a mass spectrometry-based cloning approach, we identified Semaphorin 4D (Sema4D) as an inflammatory cytokine that directly promoted cartilage destruction. Sema4d-deficient mice showed less cartilage destruction than wild-type mice in a model of rheumatoid arthritis. Sema4D induced a proinflammatory response in mouse articular chondrocytes characterized by the induction of proteolytic enzymes that degrade cartilage, such as matrix metalloproteinases (MMPs) and aggrecanases. The activation of Mmp13 and Mmp3 expression in articular chondrocytes by Sema4D did not depend on RhoA, a GTPase that mediates Sema4D-induced cytoskeletal rearrangements. Instead, it required NF-κB signaling and Ras-MEK-Erk1/2 signaling downstream of the receptors Plexin-B2 and c-Met and depended on the transcription factors IκBζ and C/EBPδ. Genetic and pharmacological blockade of these Sema4D signaling pathways inhibited MMP induction in chondrocytes and cartilage destruction in femoral head organ culture. Our results reveal a mechanism by which Sema4D signaling promotes cartilage destruction.
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Affiliation(s)
- Tomohiko Murakami
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Yoshifumi Takahata
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Kenji Hata
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Kosuke Ebina
- Department of Musculoskeletal Regenerative Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan
| | - Katsutoshi Hirose
- Department of Oral Pathology, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Lerdluck Ruengsinpinya
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
- Department of Oral Surgery and Oral Medicine, Faculty of Dentistry, Srinakharinwirot University, Bangkok 10110, Thailand
| | - Yuri Nakaminami
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Yuki Etani
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, Osaka 565-0871, Japan
| | - Sachi Kobayashi
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Takashi Maruyama
- Mucosal Immunology Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20895, USA
| | - Hiroyasu Nakano
- Department of Biochemistry, Toho University School of Medicine, Tokyo 143-8540, Japan
| | - Takehito Kaneko
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Iwate 020-8551, Japan
| | - Satoru Toyosawa
- Department of Oral Pathology, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
| | - Hiroshi Asahara
- Department of Systems BioMedicine, Tokyo Medical and Dental University, Tokyo 113-8510, Japan
- Department of Molecular Medicine, Scripps Research, La Jolla, CA 92037, USA
| | - Riko Nishimura
- Department of Molecular and Cellular Biochemistry, Osaka University Graduate School of Dentistry, Osaka 565-0871, Japan
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5
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Plexin-B2 orchestrates collective stem cell dynamics via actomyosin contractility, cytoskeletal tension and adhesion. Nat Commun 2021; 12:6019. [PMID: 34650052 PMCID: PMC8517024 DOI: 10.1038/s41467-021-26296-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 09/29/2021] [Indexed: 11/08/2022] Open
Abstract
During morphogenesis, molecular mechanisms that orchestrate biomechanical dynamics across cells remain unclear. Here, we show a role of guidance receptor Plexin-B2 in organizing actomyosin network and adhesion complexes during multicellular development of human embryonic stem cells and neuroprogenitor cells. Plexin-B2 manipulations affect actomyosin contractility, leading to changes in cell stiffness and cytoskeletal tension, as well as cell-cell and cell-matrix adhesion. We have delineated the functional domains of Plexin-B2, RAP1/2 effectors, and the signaling association with ERK1/2, calcium activation, and YAP mechanosensor, thus providing a mechanistic link between Plexin-B2-mediated cytoskeletal tension and stem cell physiology. Plexin-B2-deficient stem cells exhibit premature lineage commitment, and a balanced level of Plexin-B2 activity is critical for maintaining cytoarchitectural integrity of the developing neuroepithelium, as modeled in cerebral organoids. Our studies thus establish a significant function of Plexin-B2 in orchestrating cytoskeletal tension and cell-cell/cell-matrix adhesion, therefore solidifying the importance of collective cell mechanics in governing stem cell physiology and tissue morphogenesis.
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6
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Van Battum E, Heitz-Marchaland C, Zagar Y, Fouquet S, Kuner R, Chédotal A. Plexin-B2 controls the timing of differentiation and the motility of cerebellar granule neurons. eLife 2021; 10:60554. [PMID: 34100719 PMCID: PMC8211449 DOI: 10.7554/elife.60554] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 06/07/2021] [Indexed: 11/13/2022] Open
Abstract
Plexin-B2 deletion leads to aberrant lamination of cerebellar granule neurons (CGNs) and Purkinje cells. Although in the cerebellum Plexin-B2 is only expressed by proliferating CGN precursors in the outer external granule layer (oEGL), its function in CGN development is still elusive. Here, we used 3D imaging, in vivo electroporation and live-imaging techniques to study CGN development in novel cerebellum-specific Plxnb2 conditional knockout mice. We show that proliferating CGNs in Plxnb2 mutants not only escape the oEGL and mix with newborn postmitotic CGNs. Furthermore, motility of mitotic precursors and early postmitotic CGNs is altered. Together, this leads to the formation of ectopic patches of CGNs at the cerebellar surface and an intermingling of normally time-stamped parallel fibers in the molecular layer (ML), and aberrant arborization of Purkinje cell dendrites. There results suggest that Plexin-B2 restricts CGN motility and might have a function in cytokinesis.
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Affiliation(s)
- Eljo Van Battum
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Yvrick Zagar
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Stéphane Fouquet
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Rohini Kuner
- Pharmacology Institute, Heidelberg University, Heidelberg, Germany
| | - Alain Chédotal
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
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7
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Simonetti M, Paldy E, Njoo C, Bali KK, Worzfeld T, Pitzer C, Kuner T, Offermanns S, Mauceri D, Kuner R. The impact of Semaphorin 4C/Plexin-B2 signaling on fear memory via remodeling of neuronal and synaptic morphology. Mol Psychiatry 2021; 26:1376-1398. [PMID: 31444474 PMCID: PMC7985029 DOI: 10.1038/s41380-019-0491-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/20/2019] [Accepted: 06/03/2019] [Indexed: 12/19/2022]
Abstract
Aberrant fear is a cornerstone of several psychiatric disorders. Consequently, there is large interest in elucidation of signaling mechanisms that link extracellular cues to changes in neuronal function and structure in brain pathways that are important in the generation and maintenance of fear memory and its behavioral expression. Members of the Plexin-B family of receptors for class 4 semaphorins play important roles in developmental plasticity of neurons, and their expression persists in some areas of the adult nervous system. Here, we aimed to elucidate the role of Semaphorin 4C (Sema4C) and its cognate receptor, Plexin-B2, in the expression of contextual and cued fear memory, setting a mechanistic focus on structural plasticity and exploration of contributing signaling pathways. We observed that Plexin-B2 and Sema4C are expressed in forebrain areas related to fear memory, such as the anterior cingulate cortex, amygdala and the hippocampus, and their expression is regulated by aversive stimuli that induce fear memory. By generating forebrain-specific Plexin-B2 knockout mice and analyzing fear-related behaviors, we demonstrate that Sema4C-PlexinB2 signaling plays a crucial functional role in the recent and remote recall of fear memory. Detailed neuronal morphological analyses revealed that Sema4C-PlexinB2 signaling largely mediates fear-induced structural plasticity by enhancing dendritic ramifications and modulating synaptic density in the adult hippocampus. Analyses on signaling-related mutant mice showed that these functions are mediated by PlexinB2-dependent RhoA activation. These results deliver important insights into the mechanistic understanding of maladaptive plasticity in fear circuits and have implications for novel therapeutic strategies against fear-related disorders.
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Affiliation(s)
- Manuela Simonetti
- grid.7700.00000 0001 2190 4373Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Eszter Paldy
- grid.7700.00000 0001 2190 4373Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Christian Njoo
- grid.7700.00000 0001 2190 4373Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Kiran Kumar Bali
- grid.7700.00000 0001 2190 4373Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Thomas Worzfeld
- grid.10253.350000 0004 1936 9756Institute of Pharmacology, Marburg University, Karl-von-Frisch-Str. 1, 35043 Marburg, Germany ,grid.418032.c0000 0004 0491 220XDepartment of Pharmacology, Max-Planck-Institute for Heart and Lung Research, Ludwigstrasse 43, 61231 Bad Nauheim, Germany
| | - Claudia Pitzer
- grid.7700.00000 0001 2190 4373Interdisciplinary Neurobehavioral Core, Heidelberg University, Im Neuenheimer Feld 515, 69120 Heidelberg, Germany
| | - Thomas Kuner
- grid.7700.00000 0001 2190 4373Anatomy and Cell Biology Institute, Heidelberg University, Im Neuenheimer Feld 307, 69120 Heidelberg, Germany
| | - Stefan Offermanns
- grid.418032.c0000 0004 0491 220XDepartment of Pharmacology, Max-Planck-Institute for Heart and Lung Research, Ludwigstrasse 43, 61231 Bad Nauheim, Germany
| | - Daniela Mauceri
- grid.7700.00000 0001 2190 4373Department of Neurobiology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Rohini Kuner
- Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120, Heidelberg, Germany.
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8
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Gonda Y, Namba T, Hanashima C. Beyond Axon Guidance: Roles of Slit-Robo Signaling in Neocortical Formation. Front Cell Dev Biol 2020; 8:607415. [PMID: 33425915 PMCID: PMC7785817 DOI: 10.3389/fcell.2020.607415] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 12/07/2020] [Indexed: 12/11/2022] Open
Abstract
The formation of the neocortex relies on intracellular and extracellular signaling molecules that are involved in the sequential steps of corticogenesis, ranging from the proliferation and differentiation of neural progenitor cells to the migration and dendrite formation of neocortical neurons. Abnormalities in these steps lead to disruption of the cortical structure and circuit, and underly various neurodevelopmental diseases, including dyslexia and autism spectrum disorder (ASD). In this review, we focus on the axon guidance signaling Slit-Robo, and address the multifaceted roles of Slit-Robo signaling in neocortical development. Recent studies have clarified the roles of Slit-Robo signaling not only in axon guidance but also in progenitor cell proliferation and migration, and the maturation of neocortical neurons. We further discuss the etiology of neurodevelopmental diseases, which are caused by defects in Slit-Robo signaling during neocortical formation.
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Affiliation(s)
- Yuko Gonda
- Department of Histology and Neuroanatomy, Tokyo Medical University, Tokyo, Japan
| | - Takashi Namba
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Neuroscience Center, HiLIFE – Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Carina Hanashima
- Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
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9
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Zhou X, Wahane S, Friedl MS, Kluge M, Friedel CC, Avrampou K, Zachariou V, Guo L, Zhang B, He X, Friedel RH, Zou H. Microglia and macrophages promote corralling, wound compaction and recovery after spinal cord injury via Plexin-B2. Nat Neurosci 2020; 23:337-350. [PMID: 32112058 PMCID: PMC7412870 DOI: 10.1038/s41593-020-0597-7] [Citation(s) in RCA: 128] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Tissue repair after spinal cord injury requires the mobilization of immune and glial cells to form a protective barrier that seals the wound and facilitates debris clearing, inflammatory containment and matrix compaction. This process involves corralling, wherein phagocytic immune cells become confined to the necrotic core, which is surrounded by an astrocytic border. Here we elucidate a temporally distinct gene signature in injury-activated microglia and macrophages (IAMs) that engages axon guidance pathways. Plexin-B2 is upregulated in IAMs and is required for motor sensory recovery after spinal cord injury. Plexin-B2 deletion in myeloid cells impairs corralling, leading to diffuse tissue damage, inflammatory spillover and hampered axon regeneration. Corralling begins early and requires Plexin-B2 in both microglia and macrophages. Mechanistically, Plexin-B2 promotes microglia motility, steers IAMs away from colliding cells and facilitates matrix compaction. Our data therefore establish Plexin-B2 as an important link that integrates biochemical cues and physical interactions of IAMs with the injury microenvironment during wound healing.
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Affiliation(s)
- Xiang Zhou
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Shalaka Wahane
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marie-Sophie Friedl
- Institut für Informatik, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Michael Kluge
- Institut für Informatik, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Caroline C Friedel
- Institut für Informatik, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Kleopatra Avrampou
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Venetia Zachariou
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lei Guo
- Department of Genetics and Genomic Sciences, Mount Sinai Center for Transformative Disease Modeling, Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Bin Zhang
- Department of Genetics and Genomic Sciences, Mount Sinai Center for Transformative Disease Modeling, Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Xijing He
- Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
- Xi'an International Medical Center, Xi'an, China
| | - Roland H Friedel
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Neurosurgery, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Hongyan Zou
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Neurosurgery, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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10
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Zarco N, Norton E, Quiñones-Hinojosa A, Guerrero-Cázares H. Overlapping migratory mechanisms between neural progenitor cells and brain tumor stem cells. Cell Mol Life Sci 2019; 76:3553-3570. [PMID: 31101934 PMCID: PMC6698208 DOI: 10.1007/s00018-019-03149-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 04/16/2019] [Accepted: 05/13/2019] [Indexed: 01/18/2023]
Abstract
Neural stem cells present in the subventricular zone (SVZ), the largest neurogenic niche of the mammalian brain, are able to self-renew as well as generate neural progenitor cells (NPCs). NPCs are highly migratory and traverse the rostral migratory stream (RMS) to the olfactory bulb, where they terminally differentiate into mature interneurons. NPCs from the SVZ are some of the few cells in the CNS that migrate long distances during adulthood. The migratory process of NPCs is highly regulated by intracellular pathway activation and signaling from the surrounding microenvironment. It involves modulation of cell volume, cytoskeletal rearrangement, and isolation from compact extracellular matrix. In malignant brain tumors including high-grade gliomas, there are cells called brain tumor stem cells (BTSCs) with similar stem cell characteristics to NPCs but with uncontrolled cell proliferation and contribute to tumor initiation capacity, tumor progression, invasion, and tumor maintenance. These BTSCs are resistant to chemotherapy and radiotherapy, and their presence is believed to lead to tumor recurrence at distal sites from the original tumor location, principally due to their high migratory capacity. BTSCs are able to invade the brain parenchyma by utilizing many of the migratory mechanisms used by NPCs. However, they have an increased ability to infiltrate the tight brain parenchyma and utilize brain structures such as myelin tracts and blood vessels as migratory paths. In this article, we summarize recent findings on the mechanisms of cellular migration that overlap between NPCs and BTSCs. A better understanding of the intersection between NPCs and BTSCs will to provide a better comprehension of the BTSCs' invasive capacity and the molecular mechanisms that govern their migration and eventually lead to the development of new therapies to improve the prognosis of patients with malignant gliomas.
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Affiliation(s)
- Natanael Zarco
- Department of Neurologic Surgery, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Emily Norton
- Department of Neurologic Surgery, Mayo Clinic, Jacksonville, FL, 32224, USA
- Neuroscience Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL, 32224, USA
| | - Alfredo Quiñones-Hinojosa
- Department of Neurologic Surgery, Mayo Clinic, Jacksonville, FL, 32224, USA
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA
| | - Hugo Guerrero-Cázares
- Department of Neurologic Surgery, Mayo Clinic, Jacksonville, FL, 32224, USA.
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, 32224, USA.
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The Sema3A receptor Plexin-A1 suppresses supernumerary axons through Rap1 GTPases. Sci Rep 2018; 8:15647. [PMID: 30353093 PMCID: PMC6199275 DOI: 10.1038/s41598-018-34092-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 10/06/2018] [Indexed: 01/14/2023] Open
Abstract
The highly conserved Rap1 GTPases perform essential functions during neuronal development. They are required for the polarity of neuronal progenitors and neurons as well as for neuronal migration in the embryonic brain. Neuronal polarization and axon formation depend on the precise temporal and spatial regulation of Rap1 activity by guanine nucleotide exchange factors (GEFs) and GTPases-activating proteins (GAPs). Several Rap1 GEFs have been identified that direct the formation of axons during cortical and hippocampal development in vivo and in cultured neurons. However little is known about the GAPs that limit the activity of Rap1 GTPases during neuronal development. Here we investigate the function of Sema3A and Plexin-A1 as a regulator of Rap1 GTPases during the polarization of hippocampal neurons. Sema3A was shown to suppress axon formation when neurons are cultured on a patterned substrate. Plexin-A1 functions as the signal-transducing subunit of receptors for Sema3A and displays GAP activity for Rap1 GTPases. We show that Sema3A and Plexin-A1 suppress the formation of supernumerary axons in cultured neurons, which depends on Rap1 GTPases.
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12
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Semaphorin 4C Plexin-B2 signaling in peripheral sensory neurons is pronociceptive in a model of inflammatory pain. Nat Commun 2017; 8:176. [PMID: 28765520 PMCID: PMC5539317 DOI: 10.1038/s41467-017-00341-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Accepted: 06/23/2017] [Indexed: 01/08/2023] Open
Abstract
Semaphorins and their transmembrane receptors, Plexins, are key regulators of axon guidance and development of neuronal connectivity. B-type Plexins respond to Class IV semaphorins and mediate a variety of developmental functions. Here we report that the expression of Plexin-B2 and its high-affinity ligand, Sema4C, persists in peripheral sensory neurons in adult life and is markedly increased in states of persistent pain in mice. Genetic deletion of Sema4C as well as adult-onset loss of Plexin-B2 leads to impairment of the development and duration of inflammatory hypersensitivity. Remarkably, unlike the neurodevelopmental functions of Plexin-B2 that solely rely on Ras signaling, we obtained genetic and pharmacological evidence for a requirement of RhoA-ROCK-dependent mechanisms as well as TRPA1 sensitization in pronociceptive functions of Sema4C-Plexin-B2 signaling in adult life. These results suggest important roles for Plexin-B2 signaling in sensory function that may be of therapeutic relevance in pathological pain. Semaphorins and their receptors are involved in neurodevelopment, but their functions in the adult nervous system are not fully understood. This study finds that semaphorin 4C and its receptor Plexin B are expressed in sensory neurons and are pronociceptive in a mouse model of inflammatory pain.
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Daviaud N, Chen K, Huang Y, Friedel RH, Zou H. Impaired cortical neurogenesis in plexin-B1 and -B2 double deletion mutant. Dev Neurobiol 2015; 76:882-99. [PMID: 26579598 DOI: 10.1002/dneu.22364] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 10/12/2015] [Accepted: 11/16/2015] [Indexed: 11/08/2022]
Abstract
Mammalian cortical expansion is tightly controlled by fine-tuning of proliferation and differentiation of neural progenitors in a region-specific manner. How extrinsic cues interface with cell-intrinsic programs to balance proliferative versus neurogenic decisions remains an unsolved question. We examined the function of Semaphorin receptors Plexin-B1 and -B2 in corticogenesis by generating double mutants, whereby Plexin-B2 was conditionally ablated in the developing brain in a Plexin-B1 null mutant background. Absence of both Plexin-Bs resulted in cortical thinning, particularly in the caudomedial cortex. Plexin-B1/B2 double, but not single, mutants exhibited a reduced neural progenitor pool, attributable to decreased proliferation and an altered division mode favoring cell cycle exit. This resulted in deficient production of neurons throughout the neurogenic period, proportionally affecting all cortical laminae. Consistent with the in vivo data, cultured neural progenitors lacking both Plexin-B1 and -B2 displayed decreased proliferative capacity and increased spontaneous differentiation. Our study therefore defines a novel function of Plexin-B1 and -B2 in transmitting extrinsic signals to maintain proliferative and undifferentiated states of neural progenitors. As single mutants displayed no apparent cortical defects, we conclude that Plexin-B1 and -B2 play redundant or compensatory roles during forebrain development to ensure proper neuronal production and neocortical expansion. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 882-899, 2016.
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Affiliation(s)
- Nicolas Daviaud
- Fishberg Department of Neuroscience and Friedman Brain Institute, New York, New York 10029
| | - Karen Chen
- Fishberg Department of Neuroscience and Friedman Brain Institute, New York, New York 10029
| | - Yong Huang
- Fishberg Department of Neuroscience and Friedman Brain Institute, New York, New York 10029
| | - Roland H Friedel
- Fishberg Department of Neuroscience and Friedman Brain Institute, New York, New York 10029.,Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York 10029
| | - Hongyan Zou
- Fishberg Department of Neuroscience and Friedman Brain Institute, New York, New York 10029.,Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York 10029
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14
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Role of inhibition of osteogenesis function by Sema4D/Plexin-B1 signaling pathway in skeletal fluorosis in vitro. ACTA ACUST UNITED AC 2015; 35:712-715. [DOI: 10.1007/s11596-015-1495-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 06/15/2015] [Indexed: 02/05/2023]
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15
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Luque MCA, Gutierrez PS, Debbas V, Kalil J, Stolf BS. CD100 and plexins B2 and B1 mediate monocyte-endothelial cell adhesion and might take part in atherogenesis. Mol Immunol 2015; 67:559-67. [PMID: 26275342 DOI: 10.1016/j.molimm.2015.07.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 06/23/2015] [Accepted: 07/22/2015] [Indexed: 02/01/2023]
Abstract
Leukocyte migration is essential for the function of the immune system. Their recruitment from the vessels to the tissues involves sequential molecular interactions between leukocytes and endothelial cells (ECs). Many adhesion molecules involved in this process have already been described. However, additional molecules may be important in this interaction, and here we explore the potential role for CD100 and plexins in monocyte-EC binding. CD100 was shown to be involved in platelet-endothelial cell interaction, an important step in atherogenesis and thrombus formation. In a recent work we have described CD100 expression in monocytes and in macrophages and foam cells of human atherosclerotic plaques. In the present work, we have identified plexin B2 as a putative CD100 receptor in these cells. We have detected CD100 expression in the endothelium as well as in in vitro cultured endothelial cells. Blocking of CD100, plexin B1 and/or B2 in adhesion experiments have shown that both CD100 and plexins act as adhesion molecules involved in monocyte-endothelial cell binding. This effect may be mediated by CD100 expressed in both cell types, probably coupled to the receptors endothelial plexin B1 and monocytic plexin B2. These results can bring new insights about a possible biological activity of CD100 in monocyte adhesion and atherosclerosis, as well as a future candidate for targeting therapeutics.
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Affiliation(s)
- Maria Carolina A Luque
- Heart Institute of São Paulo (InCor), HC-FMUSP, São Paulo, SP, Brazil; Clinical Immunology and Allergy, Department of Clinical Medicine, University of São Paulo Medical School-HC-FMUSP, São Paulo, SP, Brazil
| | - Paulo S Gutierrez
- Heart Institute of São Paulo (InCor), HC-FMUSP, São Paulo, SP, Brazil
| | - Victor Debbas
- Heart Institute of São Paulo (InCor), HC-FMUSP, São Paulo, SP, Brazil
| | - Jorge Kalil
- Heart Institute of São Paulo (InCor), HC-FMUSP, São Paulo, SP, Brazil; Clinical Immunology and Allergy, Department of Clinical Medicine, University of São Paulo Medical School-HC-FMUSP, São Paulo, SP, Brazil; Institute for Investigation in Immunology - INCT - National Institute of Science and Technology, São Paulo, SP, Brazil
| | - Beatriz S Stolf
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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16
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Plexin-B3 suppresses excitatory and promotes inhibitory synapse formation in rat hippocampal neurons. Exp Cell Res 2015; 335:269-78. [PMID: 25989221 DOI: 10.1016/j.yexcr.2015.05.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 04/23/2015] [Accepted: 05/10/2015] [Indexed: 11/21/2022]
Abstract
Molecular mechanisms underlying synaptogenesis and synaptic plasticity have become one of the main topics in neurobiology. Increasing evidence suggests that axon guidance molecules including semaphorins and plexins participate in synapse formation and elimination. Although class B plexins are widely expressed in the brain, their role in the nervous system remains poorly characterized. We previously identified that B-plexins modulate microtubule dynamics and through this impact dendrite growth in rat hippocampal neurons. Here, we demonstrate that Plexin-B2 and Plexin-B3 are present in dendrites, but do not localize in synapses. We find that overexpression of all B-plexins leads to decreased volume of excitatory synapses, and at the same time Plexin-B1 and Plexin-B3 promote inhibitory synapse assembly. Plexin-B3 mutants revealed that these processes use different downstream pathways. While elimination of excitatory synapses is the result of Plexin-B3 binding to microtubule end binding proteins EB1 and EB3, the increase in inhibitory synapses is mediated by regulation of Ras and Rho GTPases. Overall, our findings demonstrate that Plexin-B3 contributes to regulating synapse formation.
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17
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Xia J, Swiercz JM, Bañón-Rodríguez I, Matković I, Federico G, Sun T, Franz T, Brakebusch CH, Kumanogoh A, Friedel RH, Martín-Belmonte F, Gröne HJ, Offermanns S, Worzfeld T. Semaphorin-Plexin Signaling Controls Mitotic Spindle Orientation during Epithelial Morphogenesis and Repair. Dev Cell 2015; 33:299-313. [PMID: 25892012 DOI: 10.1016/j.devcel.2015.02.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 12/17/2014] [Accepted: 02/02/2015] [Indexed: 01/02/2023]
Abstract
Morphogenesis, homeostasis, and regeneration of epithelial tissues rely on the accurate orientation of cell divisions, which is specified by the mitotic spindle axis. To remain in the epithelial plane, symmetrically dividing epithelial cells align their mitotic spindle axis with the plane. Here, we show that this alignment depends on epithelial cell-cell communication via semaphorin-plexin signaling. During kidney morphogenesis and repair, renal tubular epithelial cells lacking the transmembrane receptor Plexin-B2 or its semaphorin ligands fail to correctly orient the mitotic spindle, leading to severe defects in epithelial architecture and function. Analyses of a series of transgenic and knockout mice indicate that Plexin-B2 controls the cell division axis by signaling through its GTPase-activating protein (GAP) domain and Cdc42. Our data uncover semaphorin-plexin signaling as a central regulatory mechanism of mitotic spindle orientation necessary for the alignment of epithelial cell divisions with the epithelial plane.
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Affiliation(s)
- Jingjing Xia
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Jakub M Swiercz
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | | | - Ivana Matković
- Institute of Pharmacology, Biochemical-Pharmacological Center (BPC), University of Marburg, 35043 Marburg, Germany
| | - Giuseppina Federico
- Department of Cellular and Molecular Pathology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Tianliang Sun
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Timo Franz
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Cord H Brakebusch
- Biotech Research and Innovation Centre, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Atsushi Kumanogoh
- Department of Respiratory Medicine, Allergy and Rheumatic Diseases, Osaka University, Osaka 565-0871, Japan
| | - Roland H Friedel
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | | | - Hermann-Josef Gröne
- Department of Cellular and Molecular Pathology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Stefan Offermanns
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany; Medical Faculty, University of Frankfurt, 60590 Frankfurt, Germany
| | - Thomas Worzfeld
- Department of Pharmacology, Max-Planck-Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany; Institute of Pharmacology, Biochemical-Pharmacological Center (BPC), University of Marburg, 35043 Marburg, Germany.
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18
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Song D, Gan M, Zou J, Zhu X, Shi Q, Zhao H, Luo Z, Zhang W, Li S, Niu J, Zhu H, Chen H, Yuan C, Liu X, Yang H. Effect of (-)-epigallocatechin-3-gallate in preventing bone loss in ovariectomized rats and possible mechanisms. Int J Clin Exp Med 2014; 7:4183-90. [PMID: 25550929 PMCID: PMC4276187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 10/23/2014] [Indexed: 06/04/2023]
Abstract
UNLABELLED Despite recent developments reported in studies of (-)-epigallocatechin-3-gallate (EGCG), its early preventive effect of mitigating bone loss is not well understood. We investigated the effect of EGCG in preventing bone loss in ovariectomized (OVX) female rats, and explored the possible underlying mechanisms. Twelve-week-old female Sprague-Dawley rats, were divided into 3 groups: group A received intraperitoneal EGCG for 12 consecutive weeks, begun 3 days after ovariectomy; group B received ovariectomy alone; group C, received a sham operation. At the end of the experiment, tibias and femurs were harvested for: (1) micro-CT scanning and measurement of bone mineral density (BMD) and bone morphological parameters; (2) a 3-point bending test; (3) HE staining and an immunohistological study investigating Sema4D expression. RESULTS The BMD and BV/TV of group A were significantly higher than for the OVX group. The trabecular separation (Tb.Sp) of group A was significantly lower than for group B. RESULTS from the 3-point bending test showed no statistical significance among all the groups. Bone histological studies indicated that trabecular bone was denser in group C, while group B had less dense trabecular bone, and the bone morphological status of group A was intermediate between groups A and C. The immunohistological study demonstrated that Sema4D was more highly expressed as a percentage of the brown-stained area in group B than in the other 2 groups. CONCLUSION EGCG had a positive effect on mitigating bone loss in ovariectomized rats, and it inhibited Sema4D expression in bone tissue. Early stage supplementation of EGCG at a dose of 10 mg/kg/day after the onset of ovariectomy did not entirely eliminate bone loss.
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Affiliation(s)
- Dawei Song
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Minfeng Gan
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Jun Zou
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Xuesong Zhu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Qin Shi
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Huan Zhao
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Zongping Luo
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Wen Zhang
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Shiyan Li
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Junjie Niu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Hai Zhu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Hao Chen
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Chenxi Yuan
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Xiaochen Liu
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
| | - Huilin Yang
- Department of Orthopedics, The First Affiliated Hospital of Soochow University No. 188, Shizi Street, Suzhou, Jiangsu Province, China
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Ito T, Bai T, Tanaka T, Yoshida K, Ueyama T, Miyajima M, Negishi T, Kawasaki T, Takamatsu H, Kikutani H, Kumanogoh A, Yukawa K. Semaphorin 4D induces vaginal epithelial cell apoptosis to control mouse postnatal vaginal tissue remodeling. Mol Med Rep 2014; 11:829-36. [PMID: 25351707 PMCID: PMC4262505 DOI: 10.3892/mmr.2014.2773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Accepted: 09/09/2014] [Indexed: 11/18/2022] Open
Abstract
The opening of the mouse vaginal cavity to the skin is a postnatal tissue remodeling process that occurs at approximately five weeks of age for the completion of female genital tract maturation at puberty. The tissue remodeling process is primarily composed of a hormonally triggered apoptotic process predominantly occurring in the epithelium of the distal section of the vaginal cavity. However, the detailed mechanism underlying the apoptotic induction remains to be elucidated. In the present study, it was observed that the majority of BALB/c mice lacking the class 4 semaphorin, semaphorin 4D (Sema4D), developed imperforate vagina and hydrometrocolpos resulting in a perpetually unopened vaginal cavity regardless of a normal estrogen level comparable with that in wild-type (WT) mice. Administration of β-estradiol to infant Sema4D-deficient (Sema4D−/−) mice did not induce precocious vaginal opening, which was observed in WT mice subjected to the same β-estradiol administration, excluding the possibility that the closed vaginal phenotype was due to insufficient estrogen secretion at the time of vaginal opening. In order to assess the role of Sema4D in the postnatal vaginal tissue remodeling process, the expression of Sema4D and its receptor, plexin-B1, was examined as well as the level of apoptosis in the vaginal epithelia of five-week-old WT and Sema4D−/− mice. Immunohistochemical analyses confirmed the localization of Sema4D and plexin-B1 in the mouse vaginal epithelia. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay and immunohistochemistry detecting activated caspase-3 revealed significantly fewer apoptotic cells in situ in the vaginal mucosa of five-week-old Sema4D−/− mice compared with WT mice. The addition of recombinant Sema4D to Sema4D−/− vaginal epithelial cells in culture significantly enhanced apoptosis of the vaginal epithelial cells, demonstrating the apoptosis-inducing activity of Sema4D. The experimental reduction of plexin-B1 expression in vaginal epithelial cells demonstrated the integral role of plexin-B1 in Sema4D-induced apoptotic cell death. These results suggest a non-redundant role of Sema4D in the postnatal tissue remodeling process in five-week-old BALB/c mice, which involves the induction of vaginal epithelial cell apoptosis through Sema4D binding to plexin-B1.
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Affiliation(s)
- Takuji Ito
- Department of Physiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468‑8503, Japan
| | - Tao Bai
- Department of Obstetrics and Gynecology, Wakayama Medical University, Wakayama 641‑8509, Japan
| | - Tetsuji Tanaka
- Department of Obstetrics and Gynecology, Wakayama Medical University, Wakayama 641‑8509, Japan
| | - Kenji Yoshida
- Department of Physiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468‑8503, Japan
| | - Takashi Ueyama
- Department of Anatomy, Wakayama Medical University, Wakayama 641‑8509, Japan
| | - Masayasu Miyajima
- Institute for Animal Experimentation, Wakayama Medical University, Wakayama 641‑8509, Japan
| | - Takayuki Negishi
- Department of Physiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468‑8503, Japan
| | - Takahiko Kawasaki
- Division of Brain Function, National Institute of Genetics, Graduate University for Advanced Studies (Sokendai), Mishima 411‑8540, Japan
| | - Hyota Takamatsu
- Department of Immunopathology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565‑0871, Japan
| | - Hitoshi Kikutani
- Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565‑0871, Japan
| | - Atsushi Kumanogoh
- Department of Immunopathology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565‑0871, Japan
| | - Kazunori Yukawa
- Department of Physiology, Faculty of Pharmacy, Meijo University, Tempaku, Nagoya 468‑8503, Japan
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21
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Ito T, Bai T, Tanaka T, Yoshida K, Ueyama T, Miyajima M, Negishi T, Kawasaki T, Takamatsu H, Kikutani H, Kumanogoh A, Yukawa K. Estrogen-dependent proteolytic cleavage of semaphorin 4D and plexin-B1 enhances semaphorin 4D-induced apoptosis during postnatal vaginal remodeling in pubescent mice. PLoS One 2014; 9:e97909. [PMID: 24841081 PMCID: PMC4026538 DOI: 10.1371/journal.pone.0097909] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 04/25/2014] [Indexed: 01/15/2023] Open
Abstract
Around the fifth week after birth, the vaginal cavity in female mouse pups opens to the overlaying skin. This postnatal tissue remodeling of the genital tract occurs during puberty, and it largely depends upon hormonally induced apoptosis that mainly occurs in the epithelium at the lower part of the mouse vaginal cavity. Previously, we showed that most BALB/c mice lacking the class IV Semaphorin (Sema4D) develop imperforate vagina and hydrometrocolpos; therefore, we reasoned that the absence of Sema4D-induced apoptosis in vaginal epithelial cells may cause the imperforate vagina. Sema4D signals via the Plexin-B1 receptor; nevertheless detailed mechanisms mediating this hormonally triggered apoptosis are not fully documented. To investigate the estrogen-dependent control of Sema4D signaling during the apoptosis responsible for mouse vaginal opening, we examined structural and functional modulation of Sema4D, Plexin-B1, and signaling molecules by analyzing both wild-type and Sema4D−/− mice with or without ovariectomy. Both the release of soluble Sema4D and the conversion of Plexin-B1 by proteolytic processing in vaginal tissue peaked 5 weeks after birth of wild-type BALB/c mice at the time of vaginal opening. Estrogen supplementation of ovariectomized wild-type mice revealed that both the release of soluble Sema4D and the conversion of Plexin-B1 into an active form were estrogen-dependent and concordant with apoptosis. Estrogen supplementation of ovariectomized Sema4D−/− mice did not induce massive vaginal apoptosis in 5-week-old mice; therefore, Sema4D may be an essential apoptosis-inducing ligand that acts downstream of estrogen action in vaginal epithelium during this postnatal tissue remodeling. Analysis of ovariectomized mice also indicated that Sema4D contributed to estrogen-dependent dephosphorylation of Akt and ERK at the time of vaginal opening. Based on our results, we propose that apoptosis in vaginal epithelium during postnatal vaginal opening is induced by enhanced Sema4D signaling that is caused by estrogen-dependent structural changes of Sema4D and Plexin-B1.
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Affiliation(s)
- Takuji Ito
- Department of Physiology, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Tao Bai
- Department of Obstetrics and Gynecology, Wakayama Medical University, Wakayama, Japan
| | - Tetsuji Tanaka
- Department of Obstetrics and Gynecology, Wakayama Medical University, Wakayama, Japan
| | - Kenji Yoshida
- Department of Physiology, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Takashi Ueyama
- Department of Anatomy and Cell Biology, Wakayama Medical University, Wakayama, Japan
| | - Masayasu Miyajima
- Laboratory Animal Center, Wakayama Medical University, Wakayama, Japan
| | - Takayuki Negishi
- Department of Physiology, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Takahiko Kawasaki
- Division of Brain Function, National Institute of Genetics, Graduate University for Advanced Studies (Sokendai), Mishima, Japan
| | - Hyota Takamatsu
- Department of Immunopathology, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Hitoshi Kikutani
- Department of Molecular Immunology, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Atsushi Kumanogoh
- Department of Immunopathology, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Kazunori Yukawa
- Department of Physiology, Faculty of Pharmacy, Meijo University, Nagoya, Japan
- * E-mail:
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22
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Azzarelli R, Pacary E, Garg R, Garcez P, van den Berg D, Riou P, Ridley AJ, Friedel RH, Parsons M, Guillemot F. An antagonistic interaction between PlexinB2 and Rnd3 controls RhoA activity and cortical neuron migration. Nat Commun 2014; 5:3405. [PMID: 24572910 PMCID: PMC3939360 DOI: 10.1038/ncomms4405] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 02/06/2014] [Indexed: 02/06/2023] Open
Abstract
A transcriptional programme initiated by the proneural factors Neurog2 and Ascl1 controls successive steps of neurogenesis in the embryonic cerebral cortex. Previous work has shown that proneural factors also confer a migratory behaviour to cortical neurons by inducing the expression of the small GTP-binding proteins such as Rnd2 and Rnd3. However, the directionality of radial migration suggests that migrating neurons also respond to extracellular signal-regulated pathways. Here we show that the Plexin B2 receptor interacts physically and functionally with Rnd3 and stimulates RhoA activity in migrating cortical neurons. Plexin B2 competes with p190RhoGAP for binding to Rnd3, thus blocking the Rnd3-mediated inhibition of RhoA and also recruits RhoGEFs to directly stimulate RhoA activity. Thus, an interaction between the cell-extrinsic Plexin signalling pathway and the cell-intrinsic Ascl1-Rnd3 pathway determines the level of RhoA activity appropriate for cortical neuron migration.
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Affiliation(s)
- Roberta Azzarelli
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
- Present address: Hutchison/MRC Research Centre, University of Cambridge, Box 197, Biomedical Campus, Cambridge CB2 0XZ, UK
| | - Emilie Pacary
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
- Present address: INSERM, Neurocentre Magendie, Physiopathologie de la Plasticité Neuronale, U862, Bordeaux F-33000, France or University Bordeaux, Neurocentre Magendie, Physiopathologie de la plasticité neuronale, U862, Bordeaux F-33000, France
| | - Ritu Garg
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Patricia Garcez
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Debbie van den Berg
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Philippe Riou
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
- Present address: Protein Phosphorylation Laboratory, Cancer Research UK, London Research Institute, Lincoln's Inn Fields Laboratories, London WC2A 3LY, UK
| | - Anne J. Ridley
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Roland H. Friedel
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, 1425 Madison Avenue, New York, New York 10029, USA
| | - Maddy Parsons
- Randall Division of Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - François Guillemot
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
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Abstract
Mammalian plexins constitute a family of transmembrane receptors for semaphorins and represent critical regulators of various processes during development of the nervous, cardiovascular, skeletal, and renal system. In vitro studies have shown that plexins exert their effects via an intracellular R-Ras/M-Ras GTPase-activating protein (GAP) domain or by activation of RhoA through interaction with Rho guanine nucleotide exchange factor proteins. However, which of these signaling pathways are relevant for plexin functions in vivo is largely unknown. Using an allelic series of transgenic mice, we show that the GAP domain of plexins constitutes their key signaling module during development. Mice in which endogenous Plexin-B2 or Plexin-D1 is replaced by transgenic versions harboring mutations in the GAP domain recapitulate the phenotypes of the respective null mutants in the developing nervous, vascular, and skeletal system. We further provide genetic evidence that, unexpectedly, the GAP domain-mediated developmental functions of plexins are not brought about via R-Ras and M-Ras inactivation. In contrast to the GAP domain mutants, Plexin-B2 transgenic mice defective in Rho guanine nucleotide exchange factor binding are viable and fertile but exhibit abnormal development of the liver vasculature. Our genetic analyses uncover the in vivo context-dependence and functional specificity of individual plexin-mediated signaling pathways during development.
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Evsyukova I, Plestant C, Anton ES. Integrative mechanisms of oriented neuronal migration in the developing brain. Annu Rev Cell Dev Biol 2013; 29:299-353. [PMID: 23937349 DOI: 10.1146/annurev-cellbio-101512-122400] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The emergence of functional neuronal connectivity in the developing cerebral cortex depends on neuronal migration. This process enables appropriate positioning of neurons and the emergence of neuronal identity so that the correct patterns of functional synaptic connectivity between the right types and numbers of neurons can emerge. Delineating the complexities of neuronal migration is critical to our understanding of normal cerebral cortical formation and neurodevelopmental disorders resulting from neuronal migration defects. For the most part, the integrated cell biological basis of the complex behavior of oriented neuronal migration within the developing mammalian cerebral cortex remains an enigma. This review aims to analyze the integrative mechanisms that enable neurons to sense environmental guidance cues and translate them into oriented patterns of migration toward defined areas of the cerebral cortex. We discuss how signals emanating from different domains of neurons get integrated to control distinct aspects of migratory behavior and how different types of cortical neurons coordinate their migratory activities within the developing cerebral cortex to produce functionally critical laminar organization.
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Affiliation(s)
- Irina Evsyukova
- Neuroscience Center and the Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599;
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25
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Identification of a calmodulin-binding domain in Sema4D that regulates its exodomain shedding in platelets. Blood 2013; 121:4221-30. [PMID: 23564909 DOI: 10.1182/blood-2012-11-470609] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Semaphorin 4D (Sema4D) is a transmembrane protein that supports contact-dependent amplification of platelet activation by collagen before being gradually cleaved by the metalloprotease ADAM17, as we have previously shown. Cleavage releases a soluble 120-kDa exodomain fragment for which receptors exist on platelets and endothelial cells. Here we have examined the mechanism that regulates Sema4D exodomain cleavage. The results show that the membrane-proximal cytoplasmic domain of Sema4D contains a binding site for calmodulin within the polybasic region Arg762-Lys779. Coprecipitation studies show that Sema4D and calmodulin are associated in resting platelets, forming a complex that dissociates upon platelet activation by the agonists that trigger Sema4D cleavage. Inhibiting calmodulin with W7 or introducing a membrane-permeable peptide corresponding to the calmodulin-binding site is sufficient to trigger the dissociation of Sema4D from calmodulin and initiate cleavage. Conversely, deletion of the calmodulin-binding site causes constitutive shedding of Sema4D. These results show that (1) Sema4D is a calmodulin-binding protein with a site of interaction in its membrane-proximal cytoplasmic domain, (2) platelet agonists cause dissociation of the calmodulin-Sema4D complex, and (3) dissociation of the complex is sufficient to trigger ADAM17-dependent cleavage of Sema4D, releasing a bioactive fragment.
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26
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Plexin-B2 regulates the proliferation and migration of neuroblasts in the postnatal and adult subventricular zone. J Neurosci 2013; 32:16892-905. [PMID: 23175841 DOI: 10.1523/jneurosci.0344-12.2012] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the postnatal forebrain, the subventricular zone (SVZ) contains a pool of undifferentiated cells, which proliferate and migrate along the rostral migratory stream (RMS) to the olfactory bulb and differentiate into granule cells and periglomerular cells. Plexin-B2 is a semaphorin receptor previously known to act on neuronal proliferation in the embryonic brain and neuronal migration in the cerebellum. We show here that, in the postnatal and adult CNS, Plexin-B2 is expressed in the subventricular zone lining the telencephalic ventricles and in the rostral migratory stream. We analyzed Plxnb2(-/-) mice and found that there is a marked reduction in the proliferation of SVZ cells in the mutant. Plexin-B2 expression is downregulated in the olfactory bulb as interneurons initiate radial migration. BrdU labeling and GFP electroporation into postnatal SVZ, in addition to time-lapse videomicroscopy, revealed that neuroblasts deficient for Plexin-B2 migrate faster than control ones and leave the RMS more rapidly. Overall, these results show that Plexin-B2 plays a role in postnatal neurogenesis and in the migration of SVZ-derived neuroblasts.
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27
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Hota PK, Buck M. Plexin structures are coming: opportunities for multilevel investigations of semaphorin guidance receptors, their cell signaling mechanisms, and functions. Cell Mol Life Sci 2012; 69:3765-805. [PMID: 22744749 PMCID: PMC11115013 DOI: 10.1007/s00018-012-1019-0] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 04/09/2012] [Accepted: 04/11/2012] [Indexed: 01/13/2023]
Abstract
Plexin transmembrane receptors and their semaphorin ligands, as well as their co-receptors (Neuropilin, Integrin, VEGFR2, ErbB2, and Met kinase) are emerging as key regulatory proteins in a wide variety of developmental, regenerative, but also pathological processes. The diverse arenas of plexin function are surveyed, including roles in the nervous, cardiovascular, bone and skeletal, and immune systems. Such different settings require considerable specificity among the plexin and semaphorin family members which in turn are accompanied by a variety of cell signaling networks. Underlying the latter are the mechanistic details of the interactions and catalytic events at the molecular level. Very recently, dramatic progress has been made in solving the structures of plexins and of their complexes with associated proteins. This molecular level information is now suggesting detailed mechanisms for the function of both the extracellular as well as the intracellular plexin regions. Specifically, several groups have solved structures for extracellular domains for plexin-A2, -B1, and -C1, many in complex with semaphorin ligands. On the intracellular side, the role of small Rho GTPases has been of particular interest. These directly associate with plexin and stimulate a GTPase activating (GAP) function in the plexin catalytic domain to downregulate Ras GTPases. Structures for the Rho GTPase binding domains have been presented for several plexins, some with Rnd1 bound. The entire intracellular domain structure of plexin-A1, -A3, and -B1 have also been solved alone and in complex with Rac1. However, key aspects of the interplay between GTPases and plexins remain far from clear. The structural information is helping the plexin field to focus on key questions at the protein structural, cellular, as well as organism level that collaboratoria of investigations are likely to answer.
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Affiliation(s)
- Prasanta K. Hota
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
| | - Matthias Buck
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Department of Neuroscience, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Comprehensive Cancer Center, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
- Center for Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106 USA
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28
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Sema4D as an inhibitory regulator in oligodendrocyte development. Mol Cell Neurosci 2012; 49:290-9. [DOI: 10.1016/j.mcn.2011.12.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 11/15/2011] [Accepted: 12/06/2011] [Indexed: 12/28/2022] Open
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29
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Suppression of bone formation by osteoclastic expression of semaphorin 4D. Nat Med 2011; 17:1473-80. [PMID: 22019888 DOI: 10.1038/nm.2489] [Citation(s) in RCA: 350] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 08/22/2011] [Indexed: 12/18/2022]
Abstract
Most of the currently available drugs for osteoporosis inhibit osteoclastic bone resorption; only a few drugs promote osteoblastic bone formation. It is thus becoming increasingly necessary to identify the factors that regulate bone formation. We found that osteoclasts express semaphorin 4D (Sema4D), previously shown to be an axon guidance molecule, which potently inhibits bone formation. The binding of Sema4D to its receptor Plexin-B1 on osteoblasts resulted in the activation of the small GTPase RhoA, which inhibits bone formation by suppressing insulin-like growth factor-1 (IGF-1) signaling and by modulating osteoblast motility. Sema4d-/- mice, Plxnb1-/- mice and mice expressing a dominant-negative RhoA specifically in osteoblasts showed an osteosclerotic phenotype due to augmented bone formation. Notably, Sema4D-specific antibody treatment markedly prevented bone loss in a model of postmenopausal osteoporosis. Thus, Sema4D has emerged as a new therapeutic target for the discovery and development of bone-increasing drugs.
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30
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Perälä N, Sariola H, Immonen T. More than nervous: the emerging roles of plexins. Differentiation 2011; 83:77-91. [PMID: 22099179 DOI: 10.1016/j.diff.2011.08.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 07/27/2011] [Accepted: 08/04/2011] [Indexed: 12/30/2022]
Abstract
Plexins are the receptors for semaphorins, a large family of axon guidance cues. Accordingly, the role of plexins in the development of the nervous system was the first to be acknowledged. However, the expression of plexins is not restricted to neuronal cells, and recent research has been increasingly focused on the roles of plexin-semaphorin signalling outside of the nervous system. During embryogenesis, plexins regulate the development of many organs, including the cardiovascular system, skeleton and kidney. They have also been shown to be involved in immune system functions and tumour progression. Analyses of the plexin signalling in different tissues and cell types have provided new insight to the versatility of plexin interactions with semaphorins and other cell-surface receptors. In this review we try to summarise the current understanding of the roles of plexins in non-neural development and immunity.
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Affiliation(s)
- Nina Perälä
- Institute of Biomedicine/Biochemistry and Developmental Biology, Biomedicum Helsinki, University of Helsinki, Finland
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31
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Roney KE, O'Connor BP, Wen H, Holl EK, Guthrie EH, Davis BK, Jones SW, Jha S, Sharek L, Garcia-Mata R, Bear JE, Ting JPY. Plexin-B2 negatively regulates macrophage motility, Rac, and Cdc42 activation. PLoS One 2011; 6:e24795. [PMID: 21966369 PMCID: PMC3179467 DOI: 10.1371/journal.pone.0024795] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 08/22/2011] [Indexed: 11/18/2022] Open
Abstract
Plexins are cell surface receptors widely studied in the nervous system, where they mediate migration and morphogenesis though the Rho family of small GTPases. More recently, plexins have been implicated in immune processes including cell-cell interaction, immune activation, migration, and cytokine production. Plexin-B2 facilitates ligand induced cell guidance and migration in the nervous system, and induces cytoskeletal changes in overexpression assays through RhoGTPase. The function of Plexin-B2 in the immune system is unknown. This report shows that Plexin-B2 is highly expressed on cells of the innate immune system in the mouse, including macrophages, conventional dendritic cells, and plasmacytoid dendritic cells. However, Plexin-B2 does not appear to regulate the production of proinflammatory cytokines, phagocytosis of a variety of targets, or directional migration towards chemoattractants or extracellular matrix in mouse macrophages. Instead, Plxnb2−/− macrophages have greater cellular motility than wild type in the unstimulated state that is accompanied by more active, GTP-bound Rac and Cdc42. Additionally, Plxnb2−/− macrophages demonstrate faster in vitro wound closure activity. Studies have shown that a closely related family member, Plexin-B1, binds to active Rac and sequesters it from downstream signaling. The interaction of Plexin-B2 with Rac has only been previously confirmed in yeast and bacterial overexpression assays. The data presented here show that Plexin-B2 functions in mouse macrophages as a negative regulator of the GTPases Rac and Cdc42 and as a negative regulator of basal cell motility and wound healing.
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Affiliation(s)
- Kelly E. Roney
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Brian P. O'Connor
- Integrated Department of Immunology, Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Haitao Wen
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Eda K. Holl
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Elizabeth H. Guthrie
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Beckley K. Davis
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Stephen W. Jones
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Sushmita Jha
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Lisa Sharek
- Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Rafael Garcia-Mata
- Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - James E. Bear
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Integrated Department of Immunology, Center for Genes, Environment and Health, National Jewish Health, Denver, Colorado, United States of America
| | - Jenny P.-Y. Ting
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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32
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Perrinjaquet M, Sjöstrand D, Moliner A, Zechel S, Lamballe F, Maina F, Ibáñez CF. MET signaling in GABAergic neuronal precursors of the medial ganglionic eminence restricts GDNF activity in cells that express GFRα1 and a new transmembrane receptor partner. J Cell Sci 2011; 124:2797-805. [DOI: 10.1242/jcs.083717] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
GDNF (glial cell line-derived neurotrophic factor) promotes the differentiation and migration of GABAergic neuronal precursors of the medial ganglionic eminence (MGE). These functions are dependent on the GPI-anchored receptor GFRα1, but independent of its two known transmembrane receptor partners RET and NCAM. Here we show that soluble GFRα1 is also able to promote differentiation and migration of GABAergic MGE neurons. These activities require endogenous production of GDNF. Although GDNF responsiveness is abolished in Gfra1−/− neurons, it can be restored upon addition of soluble GFRα1, a result that is only compatible with the existence of a previously unknown transmembrane signaling partner for the GDNF-GFRα1 complex in GABAergic neurons. The roles of two candidate transmembrane receptors previously implicated in GABAergic interneuron development - MET, a receptor for hepatocyte growth factor (HGF), and ErbB4, the neuregulin receptor – were examined. GDNF did not induce the activation of either receptor, nor did inhibition of MET or ErbB4 impair GDNF activity in GABAergic MGE neurons. Unexpectedly, however, inhibition of MET or HGF per se promoted neuronal differentiation and migration and enhanced the activity of GDNF on MGE neurons. These effects were dependent on endogenous GDNF and GFRα1, suggesting that MET signaling negatively regulates GDNF activity in the MGE. In agreement with this, Met mutant MGE neurons showed enhanced responses to GDNF and inhibition of MET or HGF increased Gfra1 mRNA expression in MGE cells. In vivo, expression of MET and GFRα1 overlapped in the MGE, and a loss-of-function mutation in Met increased Gfra1 expression in this region. Together, these observations demonstrate the existence of a novel transmembrane receptor partner for the GDNF–GFRα1 complex and uncover an unexpected interplay between GDNF–GFRα1 and HGF–MET signaling in the early diversification of cortical GABAergic interneuron subtypes.
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Affiliation(s)
| | - Dan Sjöstrand
- Department of Neuroscience, Karolinska Institute, S-171 77 Stockholm, Sweden
| | - Annalena Moliner
- Department of Neuroscience, Karolinska Institute, S-171 77 Stockholm, Sweden
| | - Sabrina Zechel
- Department of Neuroscience, Karolinska Institute, S-171 77 Stockholm, Sweden
| | - Fabienne Lamballe
- Institut de Biologie du Développement de Marseille Luminy (IBDML), CNRS UMR 6216, Parc scientifique et technologique de Luminy–case 907, 13288 Marseille cedex 09, France
| | - Flavio Maina
- Institut de Biologie du Développement de Marseille Luminy (IBDML), CNRS UMR 6216, Parc scientifique et technologique de Luminy–case 907, 13288 Marseille cedex 09, France
| | - Carlos F. Ibáñez
- Department of Neuroscience, Karolinska Institute, S-171 77 Stockholm, Sweden
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33
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Pacary E, Heng J, Azzarelli R, Riou P, Castro D, Lebel-Potter M, Parras C, Bell DM, Ridley AJ, Parsons M, Guillemot F. Proneural transcription factors regulate different steps of cortical neuron migration through Rnd-mediated inhibition of RhoA signaling. Neuron 2011; 69:1069-84. [PMID: 21435554 PMCID: PMC3383999 DOI: 10.1016/j.neuron.2011.02.018] [Citation(s) in RCA: 168] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2011] [Indexed: 12/12/2022]
Abstract
Little is known of the intracellular machinery that controls the motility of newborn neurons. We have previously shown that the proneural protein Neurog2 promotes the migration of nascent cortical neurons by inducing the expression of the atypical Rho GTPase Rnd2. Here, we show that another proneural factor, Ascl1, promotes neuronal migration in the cortex through direct regulation of a second Rnd family member, Rnd3. Both Rnd2 and Rnd3 promote neuronal migration by inhibiting RhoA signaling, but they control distinct steps of the migratory process, multipolar to bipolar transition in the intermediate zone and locomotion in the cortical plate, respectively. Interestingly, these divergent functions directly result from the distinct subcellular distributions of the two Rnd proteins. Because Rnd proteins also regulate progenitor divisions and neurite outgrowth, we propose that proneural factors, through spatiotemporal regulation of Rnd proteins, integrate the process of neuronal migration with other events in the neurogenic program.
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Affiliation(s)
- Emilie Pacary
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
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Wansleeben C, van Gurp L, Feitsma H, Kroon C, Rieter E, Verberne M, Guryev V, Cuppen E, Meijlink F. An ENU-mutagenesis screen in the mouse: identification of novel developmental gene functions. PLoS One 2011; 6:e19357. [PMID: 21559415 PMCID: PMC3084836 DOI: 10.1371/journal.pone.0019357] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Accepted: 03/31/2011] [Indexed: 01/16/2023] Open
Abstract
Background Mutagenesis screens in the mouse have been proven useful for the identification of novel gene functions and generation of interesting mutant alleles. Here we describe a phenotype-based screen for recessive mutations affecting embryonic development. Methodology/Principal Findings Mice were mutagenized with N-ethyl-N-nitrosurea (ENU) and following incrossing the offspring, embryos were analyzed at embryonic day 10.5. Mutant phenotypes that arose in our screen include cardiac and nuchal edema, neural tube defects, situs inversus of the heart, posterior truncation and the absence of limbs and lungs. We isolated amongst others novel mutant alleles for Dll1, Ptprb, Plexin-B2, Fgf10, Wnt3a, Ncx1, Scrib(Scrib, Scribbled homolog [Drosophila]) and Sec24b. We found both nonsense alleles leading to severe protein truncations and mutants with single-amino acid substitutions that are informative at a molecular level. Novel findings include an ectopic neural tube in our Dll1 mutant and lung defects in the planar cell polarity mutants for Sec24b and Scrib. Conclusions/Significance Using a forward genetics approach, we have generated a number of novel mutant alleles that are linked to disturbed morphogenesis during development.
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Affiliation(s)
- Carolien Wansleeben
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Léon van Gurp
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Harma Feitsma
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Carla Kroon
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Ester Rieter
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Marlies Verberne
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Victor Guryev
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Edwin Cuppen
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Frits Meijlink
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences and University Medical Centre Utrecht, Utrecht, The Netherlands
- * E-mail:
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35
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Gierdalski M, McFate T, Abbah J, Juliano SL. Migratory behavior of cells generated in ganglionic eminence cultures. J Vis Exp 2011:2583. [PMID: 21540821 PMCID: PMC3169284 DOI: 10.3791/2583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Migration of cells is a common process that leads to the development and maturation of the vertebrate central nervous system (Hatten, '99). The cerebral cortex consists of two basic neuronal types: excitatory and inhibitory. These cells arise in distinct areas and migrate into the cortex along different routes (Pearlman et al., '98). Inhibitory interneurons migrate tangentially from subcortical sources, mostly from different regions of the ganglionic eminences (Gelman et al., '09; Xu et al., '04). Their movement requires precise spatiotemporal control imposed by environmental cues, to allow for the establishment of proper cytoarchitecture and connectivity in the cerebral cortex (Caviness & Rakic, '78; Hatten, '90; Rakic, '90). To study the migratory behavior of cells generated in proliferative zones of the ganglionic eminences (GE) in newborn ferrets in vitro we used a 3 dimensional culture arrangement in a BD Matrigel Matrix. The culture setup consisted of two GE explants and a source of tested proteins extracted from the cerebral cortex and adsorbed on fluorescent latex Retrobeads IX positioned between the explants (Hasling et al., '03; Riddle et al., '97). After 2-3 days of culture, the cells start to appear at the edge of the explant showing a propensity to leave the tissue in a radial direction. Live imaging allowed observation of migratory patterns without the necessity of labeling or marking the cells. When exposed to fractions of the protein extract obtained from isochronic ferret cortex, the GE cells displayed different behaviors as judged by quantitative kinetic analysis of individual moving cells.
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Affiliation(s)
- Marcin Gierdalski
- Dept. of Anatomy, Physiology and Genetics, Uniformed Services University
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36
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Maier V, Jolicoeur C, Rayburn H, Takegahara N, Kumanogoh A, Kikutani H, Tessier-Lavigne M, Wurst W, Friedel RH. Semaphorin 4C and 4G are ligands of Plexin-B2 required in cerebellar development. Mol Cell Neurosci 2011; 46:419-31. [PMID: 21122816 PMCID: PMC3030677 DOI: 10.1016/j.mcn.2010.11.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Revised: 10/27/2010] [Accepted: 11/15/2010] [Indexed: 01/15/2023] Open
Abstract
Semaphorins and Plexins are cognate ligand-receptor families that regulate important steps during nervous system development. The Plexin-B2 receptor is critically involved in neural tube closure and cerebellar granule cell development, however, its specific ligands have only been suggested by in vitro studies. Here, we show by in vivo and in vitro analyses that the two Semaphorin-4 family members Sema4C and Sema4G are likely to be in vivo ligands of Plexin-B2. The Sema4C and Sema4G genes are expressed in the developing cerebellar cortex, and Sema4C and Sema4G proteins specifically bind to Plexin-B2 expressing cerebellar granule cells. To further elucidate their in vivo function, we have generated and analyzed Sema4C and Sema4G knockout mouse mutants. Like Plexin-B2-/- mutants, Sema4C-/- mutants reveal exencephaly and subsequent neonatal lethality with partial penetrance. Sema4C-/- mutants that bypass exencephaly are viable and fertile, but display distinctive defects of the cerebellar granule cell layer, including gaps in rostral lobules, fusions of caudal lobules, and ectopic granule cells in the molecular layer. In addition to neuronal defects, we observed in Sema4C-/- mutants also ventral skin pigmentation defects that are similar to those found in Plexin-B2-/- mutants. The Sema4G gene deletion causes no overt phenotype by itself, but combined deletion of Sema4C and Sema4G revealed an enhanced cerebellar phenotype. However, Sema4C/Sema4G double mutants showed overall less severe cerebellar phenotypes than Plexin-B2-/- mutants, indicating that further ligands of Plexin-B2 exist. In explant cultures of the developing cerebellar cortex, Sema4C promoted migration of cerebellar granule cell precursors in a Plexin-B2-dependent manner, supporting the model that a reduced migration rate of granule cell precursors is the basis for the cerebellar defects of Sema4C-/- and Sema4C/Sema4G mutants.
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Affiliation(s)
- Viola Maier
- Institute of Developmental Genetics, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Christine Jolicoeur
- Department of Biological Sciences, Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA
| | - Helen Rayburn
- Department of Biological Sciences, Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA
| | - Noriko Takegahara
- Department of Immunopathology, Immunology Frontier Research Center, Osaka University, Osaka 565-0871, Japan
| | - Atsushi Kumanogoh
- Department of Immunopathology, Immunology Frontier Research Center, Osaka University, Osaka 565-0871, Japan
| | - Hitoshi Kikutani
- Department of Molecular Immunology, Osaka University, Osaka 565-0871, Japan
| | - Marc Tessier-Lavigne
- Department of Biological Sciences, Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA
- Division of Research, Genentech Inc., South San Francisco, California 94080, USA
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Center Munich, 85764 Neuherberg, Germany
| | - Roland H. Friedel
- Institute of Developmental Genetics, Helmholtz Center Munich, 85764 Neuherberg, Germany
- Corresponding author: Roland H. Friedel, , Phone: +1 (212) 241 0937, Fax: +1 (212) 860 9279, Mount Sinai School of Medicine, Department of Developmental & Regenerative Biology, 1468 Madison Avenue, Annenberg Building, room 25-70, New York, NY 10029
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Perälä N, Peitsaro N, Sundvik M, Koivula H, Sainio K, Sariola H, Panula P, Immonen T. Conservation, expression, and knockdown of zebrafish plxnb2a and plxnb2b. Dev Dyn 2010; 239:2722-34. [DOI: 10.1002/dvdy.22397] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Zielonka M, Xia J, Friedel RH, Offermanns S, Worzfeld T. A systematic expression analysis implicates Plexin-B2 and its ligand Sema4C in the regulation of the vascular and endocrine system. Exp Cell Res 2010; 316:2477-86. [PMID: 20478304 DOI: 10.1016/j.yexcr.2010.05.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/04/2010] [Accepted: 05/06/2010] [Indexed: 12/15/2022]
Abstract
Plexins serve as receptors for semaphorins and play important roles in the developing nervous system. Plexin-B2 controls decisive developmental programs in the neural tube and cerebellum. However, whether Plexin-B2 also regulates biological functions in adult nonneuronal tissues is unknown. Here we show by two methodologically independent approaches that Plexin-B2 is expressed in discrete cell types of several nonneuronal tissues in the adult mouse. In the vasculature, Plexin-B2 is selectively expressed in functionally specialized endothelial cells. In endocrine organs, Plexin-B2 localizes to the pancreatic islets of Langerhans and to both cortex and medulla of the adrenal gland. Plexin-B2 expression is also detected in certain types of immune and epithelial cells. In addition, we report on a systematic comparison of the expression patterns of Plexin-B2 and its ligand Sema4C, which show complementarity or overlap in some but not all tissues. Furthermore, we demonstrate that Plexin-B2 and its family member Plexin-B1 display largely nonredundant expression patterns. This work establishes Plexin-B2 and Sema4C as potential regulators of the vascular and endocrine system and provides an anatomical basis to understand the biological functions of this ligand-receptor pair.
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Affiliation(s)
- Matthias Zielonka
- Max-Planck-Institute for Heart and Lung Research, Department of Pharmacology, Ludwigstr. 43, 61231 Bad Nauheim, Germany
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