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Ojiro R, Ozawa S, Zou X, Tang Q, Woo GH, Shibutani M. Similar toxicity potential of glyphosate and glyphosate-based herbicide on cerebellar development after maternal exposure in rats. ENVIRONMENTAL TOXICOLOGY 2024; 39:3040-3054. [PMID: 38314887 DOI: 10.1002/tox.24163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/10/2023] [Accepted: 01/18/2024] [Indexed: 02/07/2024]
Abstract
Studies on the effects of glyphosate (GlyP) and glyphosate-based herbicides (GBHs) on cerebellar development are extremely limited. This study examined the effects of maternal exposure to GlyP and GBH on rat cerebellar development in male offspring. From day 6 of gestation until day 21 postpartum at weaning, dams were given GlyP at 1.5% or 3.0% in diet or GBH at 1.0% in drinking water (corresponding to 0.36% GlyP). At weaning, GBH exposure was linked to increased numbers of DCX+ migrating granule cells in the cortex and TUNEL+ apoptotic cells in the internal granular layer (IGL), suggesting the disappearance of mismigrated granule cells via apoptosis. GBH also upregulated Nr4a3 and downregulated Cdk5 in the cerebellar vermis, suggesting a causal relation with the impaired granule cell development at this time. GlyP (3.0%) tended to increase in the number of DCX+ migrating granule cells in the IGL and upregulated Nr4a3 at weaning. Both compounds also upregulated genes related to granule cell migration (Astn1, Astn2, Nfia, and/or Nfix) at weaning and in adulthood, which might be an ameliorative response to delayed granule cell migration. Moreover, GBH induced Purkinje cell misalignment at weaning, which could be the result of delayed granule cell migration. In adulthood, GBH was associated with upregulation of the reelin signaling-related genes Reln, Dab1, and Efnb1, suggesting a compensatory response to Purkinje cell misalignment. GlyP induced the same gene expression changes. These results suggest that GBH reversibly disrupts cerebellar development, primarily by targeting granule cell migration and differentiation, whereas GlyP exhibited similar toxic potential as GBH.
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Affiliation(s)
- Ryota Ojiro
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Shunsuke Ozawa
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Xinyu Zou
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Qian Tang
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Gye-Hyeong Woo
- Laboratory of Histopathology, Department of Clinical Laboratory Science, Semyung University, Jecheon-si, Chungbuk, Korea
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Tokyo, Japan
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2
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Minto M, Sotelo-Fonseca JE, Ramesh V, West AE. Genome binding properties of Zic transcription factors underlie their changing functions during neuronal maturation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.04.574185. [PMID: 38260638 PMCID: PMC10802290 DOI: 10.1101/2024.01.04.574185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Background The Zic family of transcription factors (TFs) promote both proliferation and maturation of cerebellar granule neurons (CGNs), raising the question of how a single, constitutively expressed TF family can support distinct developmental processes. Here we use an integrative experimental and bioinformatic approach to discover the regulatory relationship between Zic TF binding and changing programs of gene transcription during CGN differentiation. Results We first established a bioinformatic pipeline to integrate Zic ChIP-seq data from the developing mouse cerebellum with other genomic datasets from the same tissue. In newborn CGNs, Zic TF binding predominates at active enhancers that are co-bound by developmentally-regulated TFs including Atoh1, whereas in mature CGNs, Zic TF binding consolidates toward promoters where it co-localizes with activity-regulated TFs. We then performed CUT&RUN-seq in differentiating CGNs to define both the time course of developmental shifts in Zic TF binding and their relationship to gene expression. Mapping Zic TF binding sites to genes using chromatin looping, we identified the set of Zic target genes that have altered expression in RNA-seq from Zic1 or Zic2 knockdown CGNs. Conclusion Our data show that Zic TFs are required for both induction and repression of distinct, developmentally regulated target genes through a mechanism that is largely independent of changes in Zic TF binding. We suggest that the differential collaboration of Zic TFs with other TF families underlies the shift in their biological functions across CGN development.
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Affiliation(s)
- Melyssa Minto
- Duke University, Program in Computational Biology and Bioinformatics, Durham, NC 27710
- GenOmics and Translational Research Center, RTI International, Research Triangle Park, NC 27709
| | | | | | - Anne E. West
- Duke University, Department of Neurobiology, Durham, NC 27710
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3
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Bai Y, Zhao F, Wu T, Chen F, Pang X. Actin polymerization and depolymerization in developing vertebrates. Front Physiol 2023; 14:1213668. [PMID: 37745245 PMCID: PMC10515290 DOI: 10.3389/fphys.2023.1213668] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/22/2023] [Indexed: 09/26/2023] Open
Abstract
Development is a complex process that occurs throughout the life cycle. F-actin, a major component of the cytoskeleton, is essential for the morphogenesis of tissues and organs during development. F-actin is formed by the polymerization of G-actin, and the dynamic balance of polymerization and depolymerization ensures proper cellular function. Disruption of this balance results in various abnormalities and defects or even embryonic lethality. Here, we reviewed recent findings on the structure of G-actin and F-actin and the polymerization of G-actin to F-actin. We also focused on the functions of actin isoforms and the underlying mechanisms of actin polymerization/depolymerization in cellular and organic morphogenesis during development. This information will extend our understanding of the role of actin polymerization in the physiologic or pathologic processes during development and may open new avenues for developing therapeutics for embryonic developmental abnormalities or tissue regeneration.
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Affiliation(s)
- Yang Bai
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Feng Zhao
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Tingting Wu
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Fangchun Chen
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Xiaoxiao Pang
- Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
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4
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Kim T, Park H, Tanaka-Yamamoto K, Yamamoto Y. Developmental timing-dependent organization of synaptic connections between mossy fibers and granule cells in the cerebellum. Commun Biol 2023; 6:446. [PMID: 37095324 PMCID: PMC10125988 DOI: 10.1038/s42003-023-04825-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 04/07/2023] [Indexed: 04/26/2023] Open
Abstract
The long-standing hypothesis that synapses between mossy fibers (MFs) and cerebellar granule cells (GCs) are organized according to the origins of MFs and locations of GC axons, parallel fibers (PFs), is supported by recent findings. However, the mechanisms of such organized synaptic connections remain unknown. Here, using our technique that enabled PF location-dependent labeling of GCs in mice, we confirmed that synaptic connections of GCs with specific MFs originating from the pontine nucleus (PN-MFs) and dorsal column nuclei (DCoN-MFs) were gently but differentially organized according to their PF locations. We then found that overall MF-GC synaptic connectivity was biased in a way that dendrites of GCs having nearby PFs tended to connect with the same MF terminals, implying that the MF origin- and PF location-dependent organization is associated with the overall biased MF-GC synaptic connectivity. Furthermore, the development of PN-MFs preceded that of DCoN-MFs, which matches the developmental sequence of GCs that preferentially connect with each type of these MFs. Thus, our results revealed that overall MF-GC synaptic connectivity is biased in terms of PF locations, and suggested that such connectivity is likely the result of synaptic formation between developmental timing-matched partners.
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Affiliation(s)
- Taegon Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Heeyoun Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Keiko Tanaka-Yamamoto
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
| | - Yukio Yamamoto
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
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5
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Puls R, von Haefen C, Bührer C, Endesfelder S. Protective Effect of Dexmedetomidine against Hyperoxia-Damaged Cerebellar Neurodevelopment in the Juvenile Rat. Antioxidants (Basel) 2023; 12:antiox12040980. [PMID: 37107355 PMCID: PMC10136028 DOI: 10.3390/antiox12040980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 04/29/2023] Open
Abstract
Impaired cerebellar development of premature infants and the associated impairment of cerebellar functions in cognitive development could be crucial factors for neurodevelopmental disorders. Anesthetic- and hyperoxia-induced neurotoxicity of the immature brain can lead to learning and behavioral disorders. Dexmedetomidine (DEX), which is associated with neuroprotective properties, is increasingly being studied for off-label use in the NICU. For this purpose, six-day-old Wistar rats (P6) were exposed to hyperoxia (80% O2) or normoxia (21% O2) for 24 h after DEX (5 µg/kg, i.p.) or vehicle (0.9% NaCl) application. An initial detection in the immature rat cerebellum was performed after the termination of hyperoxia at P7 and then after recovery in room air at P9, P11, and P14. Hyperoxia reduced the proportion of Calb1+-Purkinje cells and affected the dendrite length at P7 and/or P9/P11. Proliferating Pax6+-granule progenitors remained reduced after hyperoxia and until P14. The expression of neurotrophins and neuronal transcription factors/markers of proliferation, migration, and survival were also reduced by oxidative stress in different manners. DEX demonstrated protective effects on hyperoxia-injured Purkinje cells, and DEX without hyperoxia modulated neuronal transcription in the short term without any effects at the cellular level. DEX protects hyperoxia-damaged Purkinje cells and appears to differentially affect cerebellar granular cell neurogenesis following oxidative stress.
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Affiliation(s)
- Robert Puls
- Department of Neonatology, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Clarissa von Haefen
- Department of Anesthesiology and Intensive Care Medicine, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Christoph Bührer
- Department of Neonatology, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Stefanie Endesfelder
- Department of Neonatology, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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6
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Komatsuya K, Kikuchi N, Hirabayashi T, Kasahara K. The Regulatory Roles of Cerebellar Glycosphingolipid Microdomains/Lipid Rafts. Int J Mol Sci 2023; 24:ijms24065566. [PMID: 36982638 PMCID: PMC10058044 DOI: 10.3390/ijms24065566] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/17/2023] Open
Abstract
Lipid rafts are dynamic assemblies of glycosphingolipids, sphingomyelin, cholesterol, and specific proteins which are stabilized into platforms involved in the regulation of vital cellular processes. Cerebellar lipid rafts are cell surface ganglioside microdomains for the attachment of GPI-anchored neural adhesion molecules and downstream signaling molecules such as Src-family kinases and heterotrimeric G proteins. In this review, we summarize our recent findings on signaling in ganglioside GD3 rafts of cerebellar granule cells and several findings by other groups on the roles of lipid rafts in the cerebellum. TAG-1, of the contactin group of immunoglobulin superfamily cell adhesion molecules, is a phosphacan receptor. Phosphacan regulates the radial migration signaling of cerebellar granule cells, via Src-family kinase Lyn, by binding to TAG-1 on ganglioside GD3 rafts. Chemokine SDF-1α, which induces the tangential migration of cerebellar granule cells, causes heterotrimeric G protein Goα translocation to GD3 rafts. Furthermore, the functional roles of cerebellar raft-binding proteins including cell adhesion molecule L1, heterotrimeric G protein Gsα, and L-type voltage-dependent calcium channels are discussed.
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7
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Moreno-Bravo JA, Rappeneau Q, Roig-Puiggros S, Sotelo C, Chédotal A. Uncoupling axon guidance and neuronal migration in Robo3-deficient inferior olivary neurons. J Comp Neurol 2022; 530:2868-2880. [PMID: 35811330 DOI: 10.1002/cne.25381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/25/2022] [Accepted: 06/02/2022] [Indexed: 12/18/2022]
Abstract
Inferior olivary (IO) neurons are born in the dorsal hindbrain and migrate tangentially toward the ventral midline. During their dorsoventral migration, IO neurons extend long leading processes that cross the midline, transform into axons, and project into the contralateral cerebellum. In absence of the axon guidance receptor Robo3, IO axons fail to cross the midline and project to the ipsilateral cerebellum. Remarkably, the IO cell bodies still reach the midline where they form a nucleus of abnormal cytoarchitecture. The mechanisms underlying the migration of Robo3-deficient IO neurons are unknown. Here, we used three-dimensional imaging and transgenic mice to label subsets of IO neurons and study their migratory behavior in Robo3 knockout. We show that IO migration is delayed in absence of Robo3. Strikingly, Robo3-deficient IO neurons progress toward the midline in a direction opposite to their axons. This occurs through a change of polarity and the generation of a second leading process at the rear of the cell. These results suggest that Robo3 receptor controls the establishment of neuronal polarity and the coupling of axonogenesis and cell body migration in IO neurons.
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Affiliation(s)
- Juan Antonio Moreno-Bravo
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France.,Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), San Juan de Alicante, Spain
| | - Quentin Rappeneau
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | | | | | - Alain Chédotal
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
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8
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Transit Amplifying Progenitors in the Cerebellum: Similarities to and Differences from Transit Amplifying Cells in Other Brain Regions and between Species. Cells 2022; 11:cells11040726. [PMID: 35203375 PMCID: PMC8870322 DOI: 10.3390/cells11040726] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/07/2022] [Accepted: 02/15/2022] [Indexed: 12/15/2022] Open
Abstract
Transit amplification of neural progenitors/precursors is widely used in the development of the central nervous system and for tissue homeostasis. In most cases, stem cells, which are relatively less proliferative, first differentiate into transit amplifying cells, which are more proliferative, losing their stemness. Subsequently, transit amplifying cells undergo a limited number of mitoses and differentiation to expand the progeny of differentiated cells. This step-by-step proliferation is considered an efficient system for increasing the number of differentiated cells while maintaining the stem cells. Recently, we reported that cerebellar granule cell progenitors also undergo transit amplification in mice. In this review, we summarize our and others’ recent findings and the prospective contribution of transit amplification to neural development and evolution, as well as the molecular mechanisms regulating transit amplification.
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9
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Murk K, Ornaghi M, Schiweck J. Profilin Isoforms in Health and Disease - All the Same but Different. Front Cell Dev Biol 2021; 9:681122. [PMID: 34458253 PMCID: PMC8387879 DOI: 10.3389/fcell.2021.681122] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/12/2021] [Indexed: 12/11/2022] Open
Abstract
Profilins are small actin binding proteins, which are structurally conserved throughout evolution. They are probably best known to promote and direct actin polymerization. However, they also participate in numerous cell biological processes beyond the roles typically ascribed to the actin cytoskeleton. Moreover, most complex organisms express several profilin isoforms. Their cellular functions are far from being understood, whereas a growing number of publications indicate that profilin isoforms are involved in the pathogenesis of various diseases. In this review, we will provide an overview of the profilin family and "typical" profilin properties including the control of actin dynamics. We will then discuss the profilin isoforms of higher animals in detail. In terms of cellular functions, we will focus on the role of Profilin 1 (PFN1) and Profilin 2a (PFN2a), which are co-expressed in the central nervous system. Finally, we will discuss recent findings that link PFN1 and PFN2a to neurological diseases, such as amyotrophic lateral sclerosis (ALS), Fragile X syndrome (FXS), Huntington's disease and spinal muscular atrophy (SMA).
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Affiliation(s)
- Kai Murk
- Institute of Biochemistry, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Marta Ornaghi
- Institute of Biochemistry, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Juliane Schiweck
- Institute of Biochemistry, Charité Universitätsmedizin Berlin, Berlin, Germany
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10
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Shiraishi R, Kawauchi D. Epigenetic regulation in medulloblastoma pathogenesis revealed by genetically engineered mouse models. Cancer Sci 2021; 112:2948-2957. [PMID: 34050694 PMCID: PMC8353939 DOI: 10.1111/cas.14990] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 05/16/2021] [Accepted: 05/18/2021] [Indexed: 12/11/2022] Open
Abstract
Medulloblastoma is the most common malignant cerebellar tumor in children. Recent technological advances in multilayered ’omics data analysis have revealed 4 molecular subgroups of medulloblastoma (Wingless/int, Sonic hedgehog, Group3, and Group4). (Epi)genomic and transcriptomic profiling on human primary medulloblastomas has shown distinct oncogenic drivers and cellular origin(s) across the subgroups. Despite tremendous efforts to identify the molecular signals driving tumorigenesis, few of the identified targets were druggable; therefore, a further understanding of the etiology of tumors is required to establish effective molecular‐targeted therapies. Chromatin regulators are frequently mutated in medulloblastoma, prompting us to investigate epigenetic changes and the accompanying activation of oncogenic signaling during tumorigenesis. For this purpose, we have used germline and non‐germline genetically engineered mice to model human medulloblastoma and to conduct useful, molecularly targeted, preclinical studies. This review discusses the biological implications of chromatin regulator mutations during medulloblastoma pathogenesis, based on recent in vivo animal studies.
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Affiliation(s)
- Ryo Shiraishi
- Department of Biochemistry and Cellular Biology, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan.,Department of NCNP Brain Physiology and Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Daisuke Kawauchi
- Department of Biochemistry and Cellular Biology, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan
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11
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Martí-Clúa J. Incorporation of 5-Bromo-2'-deoxyuridine into DNA and Proliferative Behavior of Cerebellar Neuroblasts: All That Glitters Is Not Gold. Cells 2021; 10:cells10061453. [PMID: 34200598 PMCID: PMC8229392 DOI: 10.3390/cells10061453] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/06/2021] [Accepted: 06/07/2021] [Indexed: 12/27/2022] Open
Abstract
The synthetic halogenated pyrimidine analog, 5-bromo-2'-deoxyuridine (BrdU), is a marker of DNA synthesis. This exogenous nucleoside has generated important insights into the cellular mechanisms of the central nervous system development in a variety of animals including insects, birds, and mammals. Despite this, the detrimental effects of the incorporation of BrdU into DNA on proliferation and viability of different types of cells has been frequently neglected. This review will summarize and present the effects of a pulse of BrdU, at doses ranging from 25 to 300 µg/g, or repeated injections. The latter, following the method of the progressively delayed labeling comprehensive procedure. The prenatal and perinatal development of the cerebellum are studied. These current data have implications for the interpretation of the results obtained by this marker as an index of the generation, migration, and settled pattern of neurons in the developing central nervous system. Caution should be exercised when interpreting the results obtained using BrdU. This is particularly important when high or repeated doses of this agent are injected. I hope that this review sheds light on the effects of this toxic maker. It may be used as a reference for toxicologists and neurobiologists given the broad use of 5-bromo-2'-deoxyuridine to label dividing cells.
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Affiliation(s)
- Joaquín Martí-Clúa
- Unidad de Citología e Histología, Departament de Biologia Cellular, de Fisiologia i d'Immunologia, Facultad de Biociencias, Institut de Neurociències, Universidad Autónoma de Barcelona, Bellaterra, 08193 Barcelona, Spain
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12
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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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13
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Miyashita S, Owa T, Seto Y, Yamashita M, Aida S, Sone M, Ichijo K, Nishioka T, Kaibuchi K, Kawaguchi Y, Taya S, Hoshino M. Cyclin D1 controls development of cerebellar granule cell progenitors through phosphorylation and stabilization of ATOH1. EMBO J 2021; 40:e105712. [PMID: 34057742 PMCID: PMC8280807 DOI: 10.15252/embj.2020105712] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 03/28/2021] [Accepted: 04/01/2021] [Indexed: 12/27/2022] Open
Abstract
During development, neural progenitors are in proliferative and immature states; however, the molecular machinery that cooperatively controls both states remains elusive. Here, we report that cyclin D1 (CCND1) directly regulates both proliferative and immature states of cerebellar granule cell progenitors (GCPs). CCND1 not only accelerates cell cycle but also upregulates ATOH1 protein, an essential transcription factor that maintains GCPs in an immature state. In cooperation with CDK4, CCND1 directly phosphorylates S309 of ATOH1, which inhibits additional phosphorylation at S328 and consequently prevents S328 phosphorylation-dependent ATOH1 degradation. Additionally, PROX1 downregulates Ccnd1 expression by histone deacetylation of Ccnd1 promoter in GCPs, leading to cell cycle exit and differentiation. Moreover, WNT signaling upregulates PROX1 expression in GCPs. These findings suggest that WNT-PROX1-CCND1-ATOH1 signaling cascade cooperatively controls proliferative and immature states of GCPs. We revealed that the expression and phosphorylation levels of these molecules dynamically change during cerebellar development, which are suggested to determine appropriate differentiation rates from GCPs to GCs at distinct developmental stages. This study contributes to understanding the regulatory mechanism of GCPs as well as neural progenitors.
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Affiliation(s)
- Satoshi Miyashita
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan
| | - Tomoo Owa
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan
| | - Yusuke Seto
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan.,Laboratory of Developmental Systems, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Mariko Yamashita
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan
| | - Shogo Aida
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan.,Department of Biomolecular Science, Faculty of Science, Toho University, Chiba, Japan
| | - Masaki Sone
- Department of Biomolecular Science, Faculty of Science, Toho University, Chiba, Japan
| | - Kentaro Ichijo
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan.,Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, The University of Tokyo, Tokyo, Japan
| | - Tomoki Nishioka
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kozo Kaibuchi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yoshiya Kawaguchi
- Department of Life Science Frontiers, Center for iPS cell Research and Application (CiRA), Kyoto University, Kyoto, Japan
| | - Shinichiro Taya
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan
| | - Mikio Hoshino
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, Japan
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14
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Chen S, Zhang K, Zhang B, Jiang M, Zhang X, Guo Y, Yu Y, Qin T, Li H, Chen Q, Cai Z, Luo S, Huang Y, Hu J, Mo W. Temporarily Epigenetic Repression in Bergmann Glia Regulates the Migration of Granule Cells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:2003164. [PMID: 34026436 PMCID: PMC8132163 DOI: 10.1002/advs.202003164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 02/10/2021] [Indexed: 06/12/2023]
Abstract
Forming tight interaction with both Purkinje and granule cells (GCs), Bergmann glia (BG) are essential for cerebellar morphogenesis and neuronal homeostasis. However, how BG act in this process is unclear without comprehensive transcriptome landscape of BG. Here, high temporal-resolution investigation of transcriptomes with FACS-sorted BG revealed the dynamic expression of genes within given functions and pathways enabled BG to assist neural migration and construct neuron-glia network. It is found that the peak time of GCs migration (P7-10) strikingly coincides with the downregulation of extracellular matrix (ECM) related genes, and the disruption of which by Setdb1 ablation at P7-10 in BG leads to significant migration defect of GCs emphasizing the criticality of Nfix-Setdb1 mediated H3K9me3 repressive complex for the precise regulation of GCs migration in vivo. Thus, BG's transcriptomic landscapes offer an insight into the mechanism by which BG are in depth integrated in cerebellar neural network.
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Affiliation(s)
- Shaoxuan Chen
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
- The Department of NeuroscienceSchool of MedicineXiamen UniversityXiamen361102China
| | - Kunkun Zhang
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
- The Department of NeuroscienceSchool of MedicineXiamen UniversityXiamen361102China
| | - Boxin Zhang
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Mengyun Jiang
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Xue Zhang
- Xiang'an Hospital of Xiamen UniversitySchool of MedicineXiamen361102China
| | - Yi Guo
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Yingying Yu
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
- National Institute for Data Science in Health and MedicineXiamen UniversityXiamen361102China
| | - Tianyu Qin
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
- National Institute for Data Science in Health and MedicineXiamen UniversityXiamen361102China
| | - Hongda Li
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Qiang Chen
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Zhiyu Cai
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Site Luo
- Key Laboratory of Ministry of Education for Coast and Wetland EcosystemsCollege of the Environment and EcologyXiamen UniversityXiamen361102China
| | - Yi Huang
- Department of Clinical LaboratoryFujian Provincial HospitalFuzhou350001China
- Provincial Clinical CollegeFujian Medical UniversityFuzhou350001China
| | - Jin Hu
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
| | - Wei Mo
- State Key Laboratory of Cellular Stress BiologyThe First Affiliated Hospital of Xiamen UniversitySchool of Life SciencesXiamen UniversityXiamen361102China
- The Department of NeuroscienceSchool of MedicineXiamen UniversityXiamen361102China
- National Institute for Data Science in Health and MedicineXiamen UniversityXiamen361102China
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15
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Consalez GG, Goldowitz D, Casoni F, Hawkes R. Origins, Development, and Compartmentation of the Granule Cells of the Cerebellum. Front Neural Circuits 2021; 14:611841. [PMID: 33519389 PMCID: PMC7843939 DOI: 10.3389/fncir.2020.611841] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/17/2020] [Indexed: 12/21/2022] Open
Abstract
Granule cells (GCs) are the most numerous cell type in the cerebellum and indeed, in the brain: at least 99% of all cerebellar neurons are granule cells. In this review article, we first consider the formation of the upper rhombic lip, from which all granule cell precursors arise, and the way by which the upper rhombic lip generates the external granular layer, a secondary germinal epithelium that serves to amplify the upper rhombic lip precursors. Next, we review the mechanisms by which postmitotic granule cells are generated in the external granular layer and migrate radially to settle in the granular layer. In addition, we review the evidence that far from being a homogeneous population, granule cells come in multiple phenotypes with distinct topographical distributions and consider ways in which the heterogeneity of granule cells might arise during development.
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Affiliation(s)
- G Giacomo Consalez
- Division of Neuroscience, San Raffaele Scientific Institute, San Raffaele University, Milan, Italy
| | - Daniel Goldowitz
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Filippo Casoni
- Division of Neuroscience, San Raffaele Scientific Institute, San Raffaele University, Milan, Italy
| | - Richard Hawkes
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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16
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Pook C, Ahrens JM, Clagett-Dame M. Expression pattern of Nav2 in the murine CNS with development. Gene Expr Patterns 2020; 35:119099. [PMID: 32081718 DOI: 10.1016/j.gep.2020.119099] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 01/07/2020] [Accepted: 02/12/2020] [Indexed: 12/11/2022]
Abstract
Neuron navigator 2 (NAV2, RAINB1, POMFIL2, HELAD1, unc53H2) is essential for nervous system development. In the present study the spatial distribution of Nav2 transcript in mouse CNS during embryonic, postnatal and adult life is examined. Because multiple NAV2 proteins are predicted based on alternate promoter usage and RNA splicing, in situ hybridization was performed using probes designed to the 5' and 3' ends of the Nav2 transcript, and PCR products using primer sets spanning the length of the mRNA were also examined by real time PCR (qPCR). These studies support full-length Nav2 transcript as the predominant form in the wild-type mouse CNS. The developing cortex, hippocampus, thalamus, olfactory bulb, and granule cells (GC) within the cerebellum show the highest expression, with a similar staining pattern using either the 5'Nav2 or 3'Nav2 probe. Nav2 is expressed in GC precursors migrating over the cerebellar primordium as well as in the postmitotic premigratory cells of the external granule cell layer (EGL). It is expressed in the cornu ammonis (CA) and dentate gyrus (DG) throughout hippocampal development. In situ hybridization was combined with immunohistochemistry for Ki67, CTIP2 and Nissl staining to follow Nav2 transcript location during cortical development, where it is observed in neuroepithelial cells exiting the germinal compartments, as well as later in the cortical plate (CP) and developing cortical layers. The highest levels of Nav2 in all brain regions studied are observed in late gestation and early postnatal life which coincides with times when neurons are migrating and differentiating. A hypomorphic mouse that lacks the full-length transcript but expresses shorter transcript shows little staining in the CNS with either probe set except at the base of the cerebellum, where a shorter Nav2 transcript is detected. Using dual fluorescent probe in situ hybridization studies, these cells are identified as oligodendrocytes and are detected using both Olig1 and the 3'Nav2 probe. The identification of full-length Nav2 as the primary transcript in numerous brain regions suggests NAV2 could play a role in CNS development beyond that of its well-established role in the cerebellum.
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Affiliation(s)
- Caitlin Pook
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, WI, 53706, USA; Medical College of Wisconsin-Milwaukee Campus, Wauwatosa, WI, 53226, USA
| | - Jamie M Ahrens
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, WI, 53706, USA
| | - Margaret Clagett-Dame
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, WI, 53706, USA; Pharmaceutical Sciences Division, School of Pharmacy, University of Wisconsin, Madison, 53706, USA.
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17
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Hoffman DP, Shtengel G, Xu CS, Campbell KR, Freeman M, Wang L, Milkie DE, Pasolli HA, Iyer N, Bogovic JA, Stabley DR, Shirinifard A, Pang S, Peale D, Schaefer K, Pomp W, Chang CL, Lippincott-Schwartz J, Kirchhausen T, Solecki DJ, Betzig E, Hess HF. Correlative three-dimensional super-resolution and block-face electron microscopy of whole vitreously frozen cells. Science 2020; 367:eaaz5357. [PMID: 31949053 PMCID: PMC7339343 DOI: 10.1126/science.aaz5357] [Citation(s) in RCA: 205] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 11/20/2019] [Indexed: 12/27/2022]
Abstract
Within cells, the spatial compartmentalization of thousands of distinct proteins serves a multitude of diverse biochemical needs. Correlative super-resolution (SR) fluorescence and electron microscopy (EM) can elucidate protein spatial relationships to global ultrastructure, but has suffered from tradeoffs of structure preservation, fluorescence retention, resolution, and field of view. We developed a platform for three-dimensional cryogenic SR and focused ion beam-milled block-face EM across entire vitreously frozen cells. The approach preserves ultrastructure while enabling independent SR and EM workflow optimization. We discovered unexpected protein-ultrastructure relationships in mammalian cells including intranuclear vesicles containing endoplasmic reticulum-associated proteins, web-like adhesions between cultured neurons, and chromatin domains subclassified on the basis of transcriptional activity. Our findings illustrate the value of a comprehensive multimodal view of ultrastructural variability across whole cells.
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Affiliation(s)
- David P Hoffman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Gleb Shtengel
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - C Shan Xu
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Kirby R Campbell
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Melanie Freeman
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Lei Wang
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Daniel E Milkie
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - H Amalia Pasolli
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Nirmala Iyer
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - John A Bogovic
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Daniel R Stabley
- Neuroimaging Laboratory, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Abbas Shirinifard
- Bioimage Analysis Core, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Song Pang
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - David Peale
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Kathy Schaefer
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Wim Pomp
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Chi-Lun Chang
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | | | - Tom Kirchhausen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - David J Solecki
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Eric Betzig
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
- Department of Physics, University of California, Berkeley, CA 94720, USA
- Howard Hughes Medical Institute, Berkeley, CA 94720, USA
- Helen Wills Neuroscience Institute, Berkeley, CA 94720, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Harald F Hess
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
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18
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Jandeaux C, Kuchcinski G, Ternynck C, Riquet A, Leclerc X, Pruvo JP, Soto-Ares G. Biometry of the Cerebellar Vermis and Brain Stem in Children: MR Imaging Reference Data from Measurements in 718 Children. AJNR Am J Neuroradiol 2019; 40:1835-1841. [PMID: 31624120 DOI: 10.3174/ajnr.a6257] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/21/2019] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE Objective and quantitative data to define cerebellar vermis and/or brain stem hypoplasia in children are lacking. Our aim was to provide MR imaging biometric references for the cerebellar vermis and brain stem from a large cohort of children with normal cerebellums. MATERIALS AND METHODS The MR imaging data were retrospectively selected from our hospital data base from January 1, 2014, to December 31, 2017. All MR imaging examinations of children between 1 day and 15 years of age, including midline sagittal sections, were included. Children with a clinical history or MR imaging abnormalities that may affect the posterior fossa were excluded. We manually measured four 2D parameters: vermian height, anterior-posterior diameter of the vermis, anterior-posterior diameter of the midbrain-pons junction, and anterior-posterior midpons diameter. The inter- and intraobserver agreement was evaluated. RESULTS Seven hundred eighteen children were included (372 boys and 346 girls), from 1 day to 15 years of age. Normal values (third to 97th percentiles) were provided for each parameter. The vermis parameters showed a rapid growth phase during the first year, a slower growth until the fifth year, and finally a near-plateau phase. The brain stem parameters showed more progressive growth. The intra- and interobserver agreement was excellent for all parameters. CONCLUSIONS We provide reference biometric data of the vermis and the brain stem using simple and reproducible measurements that are easy to use in daily practice. The relevance of these 2D measurements should be further validated in diseases associated with cerebellar abnormalities.
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Affiliation(s)
- C Jandeaux
- From the Departments of Neuroradiology (C.J., G.K., X.L., J.-P.P., G.S.-A.)
| | - G Kuchcinski
- From the Departments of Neuroradiology (C.J., G.K., X.L., J.-P.P., G.S.-A.)
| | | | - A Riquet
- Neuropediatrics (A.R.), Centre Hospitalier Universitaire Lille, Lille, France
| | - X Leclerc
- From the Departments of Neuroradiology (C.J., G.K., X.L., J.-P.P., G.S.-A.)
| | - J-P Pruvo
- From the Departments of Neuroradiology (C.J., G.K., X.L., J.-P.P., G.S.-A.)
| | - G Soto-Ares
- From the Departments of Neuroradiology (C.J., G.K., X.L., J.-P.P., G.S.-A.)
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19
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White CL, Jayasekara WSN, Picard D, Chen J, Watkins DN, Cain JE, Remke M, Gough DJ. A Sexually Dimorphic Role for STAT3 in Sonic Hedgehog Medulloblastoma. Cancers (Basel) 2019; 11:cancers11111702. [PMID: 31683879 PMCID: PMC6895805 DOI: 10.3390/cancers11111702] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 01/04/2023] Open
Abstract
Medulloblastoma is the most common malignant brain tumor in children and represents 20% of all pediatric central nervous system neoplasms. While advances in surgery, radiation and chemotherapy have improved overall survival, the lifelong sequelae of these treatments represent a major health care burden and have led to ongoing efforts to find effective targeted treatments. There is a well-recognized male bias in medulloblastoma diagnosis, although the mechanism remains unknown. Herein, we identify a sex-specific role for the transcription factor Signal Transducer and Activator of Transcription 3 (STAT3) in the Sonic Hedgehog (SHH) medulloblastoma subgroup. Specific deletion of Stat3 from granule cell precursors in a spontaneous mouse model of SHH medulloblastoma completely protects male, but not female mice from tumor initiation. Segregation of SHH medulloblastoma patients into high and low STAT3 expressing cohorts shows that low STAT3 expression correlates with improved overall survival in male patients. We observe sex specific changes in IL-10 and IL-6 expression and show that IL-6 stimulation enhances SHH-mediated gene transcription in a STAT3-dependent manner. Together these data identify STAT3 as a key molecule underpinning the sexual dimorphism in medulloblastoma.
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Affiliation(s)
- Christine L White
- Centre for Cancer Research, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Victoria 3168, Australia.
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia.
| | - W Samantha N Jayasekara
- Centre for Cancer Research, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Victoria 3168, Australia.
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia.
| | - Daniel Picard
- Department of Pediatric Neuro-Oncogenomics, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
- German Cancer Consortium (DKTK), Partner Site Essen, 45147 Düsseldorf, Germany.
- Department of Pediatric Oncology, Hematology, Clinical Immunology, Institute of Neuropathology, Medical Faculty, University Hospital Düsseldorf, 40225 Düsseldorf, Germany.
| | - Jasmine Chen
- Centre for Cancer Research, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Victoria 3168, Australia.
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia.
| | - D Neil Watkins
- Centre for Cancer Research, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Victoria 3168, Australia.
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia.
- Research Institute in Oncology and Hematology, Cancer Care Manitoba, Winnipeg, MB R3E 0V9, Canada.
- Department of Internal Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
| | - Jason E Cain
- Centre for Cancer Research, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Victoria 3168, Australia.
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia.
| | - Marc Remke
- Department of Pediatric Neuro-Oncogenomics, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany.
- German Cancer Consortium (DKTK), Partner Site Essen, 45147 Düsseldorf, Germany.
- Department of Pediatric Oncology, Hematology, Clinical Immunology, Institute of Neuropathology, Medical Faculty, University Hospital Düsseldorf, 40225 Düsseldorf, Germany.
| | - Daniel J Gough
- Centre for Cancer Research, Hudson Institute of Medical Research, 27-31 Wright St, Clayton, Victoria 3168, Australia.
- Department of Molecular and Translational Sciences, Monash University, Clayton, Victoria 3800, Australia.
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20
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Shiraishi RD, Miyashita S, Yamashita M, Adachi T, Shimoda MM, Owa T, Hoshino M. Expression of transcription factors and signaling molecules in the cerebellar granule cell development. Gene Expr Patterns 2019; 34:119068. [PMID: 31437514 DOI: 10.1016/j.gep.2019.119068] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 07/29/2019] [Accepted: 08/14/2019] [Indexed: 01/16/2023]
Abstract
Cerebellar granule cell precursors (GCPs) and granule cells (GCs) constitute a good model system to investigate proliferation of neural precursors and differentiation of neurons. During development, GCPs proliferate in the outer external granule cell layer (outer EGL) and then exit the cell cycle in the inner EGL to become GCs, which inwardly migrate to the inner granule cell layer (IGL). Misregulation of GCP proliferation or GC differentiation leads to maldevelopment of the cerebellum and the formation of a cerebellar tumor, medulloblastoma. Despite many efforts in this field, the mechanisms underlying GC development remain elusive. In this study, we performed detailed immunostaining in the developing cerebellum, with particular focus on GCPs and GCs, looking at several transcription factors, signaling molecules, cell cycle regulators, some of which are known to regulate neural development. Interestingly, we found distinct distribution patterns of certain proteins within the outer and inner EGL, suggesting the existence of subpopulations of GCPs and GCs in those layers. This study provides a basis for future studies on the cerebellar GC development and medulloblastoma.
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Affiliation(s)
- Ryo D Shiraishi
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan; Department of NCNP Brain Function and Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, TMDU, Tokyo, 113- 8510, Japan
| | - Sathoshi Miyashita
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan
| | - Mariko Yamashita
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan; Department of NCNP Brain Function and Pathology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, TMDU, Tokyo, 113- 8510, Japan
| | - Toma Adachi
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan; Department of Life Science and Medical Bioscience, Graduate School of Advance Science and Engineering, TWIns, Waseda University, Tokyo, 162-8480, Japan
| | - Mana M Shimoda
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan; Department of Life Science and Medical Bioscience, Graduate School of Advance Science and Engineering, TWIns, Waseda University, Tokyo, 162-8480, Japan
| | - Tomoo Owa
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan
| | - Mikio Hoshino
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, NCNP, Tokyo, 187-8502, Japan.
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21
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Peng J, Sheng AL, Xiao Q, Shen L, Ju XC, Zhang M, He ST, Wu C, Luo ZG. Single-cell transcriptomes reveal molecular specializations of neuronal cell types in the developing cerebellum. J Mol Cell Biol 2019; 11:636-648. [PMID: 30690467 PMCID: PMC6788728 DOI: 10.1093/jmcb/mjy089] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 12/18/2018] [Accepted: 12/28/2018] [Indexed: 12/15/2022] Open
Abstract
The cerebellum is critical for controlling motor and non-motor functions via cerebellar circuit that is composed of defined cell types, which approximately account for more than half of neurons in mammals. The molecular mechanisms controlling developmental progression and maturation processes of various cerebellar cell types need systematic investigation. Here, we analyzed transcriptome profiles of 21119 single cells of the postnatal mouse cerebellum and identified eight main cell clusters. Functional annotation of differentially expressed genes revealed trajectory hierarchies of granule cells (GCs) at various states and implied roles of mitochondrion and ATPases in the maturation of Purkinje cells (PCs), the sole output cells of the cerebellar cortex. Furthermore, we analyzed gene expression patterns and co-expression networks of 28 ataxia risk genes, and found that most of them are related with biological process of mitochondrion and around half of them are enriched in PCs. Our results also suggested core transcription factors that are correlated with interneuron differentiation and characteristics for the expression of secretory proteins in glia cells, which may participate in neuronal modulation. Thus, this study presents a systematic landscape of cerebellar gene expression in defined cell types and a general gene expression framework for cerebellar development and dysfunction.
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Affiliation(s)
- Jian Peng
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ai-li Sheng
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Qi Xiao
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Libing Shen
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Xiang-Chun Ju
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Min Zhang
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
| | - Si-Ting He
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Chao Wu
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
- ShanghaiTech University, Shanghai, China
| | - Zhen-Ge Luo
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Beijing, China
- ShanghaiTech University, Shanghai, China
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
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22
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Molina V, Rodríguez-Vázquez L, Martí J. Patterns of Apoptosis and Autophagy Activation After Hydroxyurea Exposure in the Rat Cerebellar External Granular Layer: an Immunoperoxidase and Ultrastructural Analysis. Neurotox Res 2019; 37:93-99. [DOI: 10.1007/s12640-019-00094-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 07/24/2019] [Accepted: 07/30/2019] [Indexed: 12/14/2022]
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23
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Iulianella A, Wingate RJ, Moens CB, Capaldo E. The generation of granule cells during the development and evolution of the cerebellum. Dev Dyn 2019; 248:506-513. [PMID: 31131952 DOI: 10.1002/dvdy.64] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/10/2019] [Accepted: 05/16/2019] [Indexed: 12/19/2022] Open
Abstract
The cerebellum coordinates vestibular input into the hindbrain to control balance and movement, and its anatomical complexity is increasingly viewed as a high-throughput processing center for sensory and cognitive functions. Cerebellum development however is relatively simple, and arises from a specialized structure in the anterior hindbrain called the rhombic lip, which along with the ventricular zone of the rostral-most dorsal hindbrain region, give rise to the distinct cell types that constitute the cerebellum. Granule cells, being the most numerous cell types, arise from the rhombic lip and form a dense and distinct layer of the cerebellar cortex. In this short review, we describe the various strategies used by amniotes and anamniotes to generate and diversify granule cell types during cerebellar development.
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Affiliation(s)
- Angelo Iulianella
- Department of Medical Neuroscience and Brain Repair Centre, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Richard J Wingate
- MRC Centre of Neurodevelopmental Disorders, King's College London, London, UK
| | - Cecilia B Moens
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Emily Capaldo
- Department of Medical Neuroscience and Brain Repair Centre, Life Science Research Institute, Dalhousie University, Halifax, Nova Scotia, Canada
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NeuroD2 controls inhibitory circuit formation in the molecular layer of the cerebellum. Sci Rep 2019; 9:1448. [PMID: 30723302 PMCID: PMC6363755 DOI: 10.1038/s41598-018-37850-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 12/12/2018] [Indexed: 12/14/2022] Open
Abstract
The cerebellar cortex is involved in the control of diverse motor and non-motor functions. Its principal circuit elements are the Purkinje cells that integrate incoming excitatory and local inhibitory inputs and provide the sole output of the cerebellar cortex. However, the transcriptional control of circuit assembly in the cerebellar cortex is not well understood. Here, we show that NeuroD2, a neuronal basic helix-loop-helix (bHLH) transcription factor, promotes the postnatal survival of both granule cells and molecular layer interneurons (basket and stellate cells). However, while NeuroD2 is not essential for the integration of surviving granule cells into the excitatory circuit, it is required for the terminal differentiation of basket cells. Axons of surviving NeuroD2-deficient basket cells follow irregular trajectories and their inhibitory terminals are virtually absent from Purkinje cells in Neurod2 mutants. As a result inhibitory, but not excitatory, input to Purkinje cells is strongly reduced in the absence of NeuroD2. Together, we conclude that NeuroD2 is necessary to instruct a terminal differentiation program in basket cells that regulates targeted axon growth and inhibitory synapse formation. An imbalance of excitation and inhibition in the cerebellar cortex affecting Purkinje cell output may underlay impaired adaptive motor learning observed in Neurod2 mutants.
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25
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Mandalos NP, Karampelas I, Saridaki M, McKay RDG, Cohen ML, Remboutsika E. A Role for Sox2 in the Adult Cerebellum. ACTA ACUST UNITED AC 2018; 8. [PMID: 30568848 DOI: 10.4172/2157-7633.1000433] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The cerebellum, a derivative of the hindbrain, plays a crucial role in balance and posture as well as in higher cognitive and locomotive processes. Cerebellar development is initiated during the segmental phase of hindbrain formation. Here, we describe the phenotype, of a single surviving adult conditional mouse mutant mouse, in which Sox2 function is ablated in embryonic radial glial cells by means of hGFAP-CRE. The single Sox2RGINV/mosaic adult mutant mouse displays motor disability, microsomia, reduced Central Nervous System (CNS) size and cerebellar defects associated with human genetically related congenital abnormalities.
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Affiliation(s)
- Nikolaos Panagiotis Mandalos
- National and Kapodistrian University of Athens, School of Medicine, Department of Pediatrics, Athens, Greece.,Stem Cell Biology Laboratory, Biomedical Sciences Research Centre "Alexander Fleming", Vari-Attica, Greece
| | - Ioannis Karampelas
- Department of Neurosurgery, University Hospitals Case Medical Center, Cleveland, OH, USA
| | - Marannia Saridaki
- Stem Cell Biology Laboratory, Biomedical Sciences Research Centre "Alexander Fleming", Vari-Attica, Greece
| | - Ronald D G McKay
- The Lieber Institute for Brain Development, Basic Sciences Division, Johns Hopkins Medical Campus, Baltimore, USA
| | - Mark L Cohen
- Department of Pathology, University Hospitals of Cleveland, Case Western Reserve School of Medicine, Cleveland, OH, USA
| | - Eumorphia Remboutsika
- National and Kapodistrian University of Athens, School of Medicine, Department of Pediatrics, Athens, Greece.,Stem Cell Biology Laboratory, Biomedical Sciences Research Centre "Alexander Fleming", Vari-Attica, Greece.,The Lieber Institute for Brain Development, Basic Sciences Division, Johns Hopkins Medical Campus, Baltimore, USA
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Rodríguez-Vázquez L, Martí J. An Animal Model for Assessing the Effects of Hydroxyurea Exposure Suggests That the Administration of This Agent to Pregnant Women and Young Infants May Not Be as Safe as We Thought. Int J Mol Sci 2018; 19:E3986. [PMID: 30544930 PMCID: PMC6320814 DOI: 10.3390/ijms19123986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 12/04/2018] [Accepted: 12/06/2018] [Indexed: 12/30/2022] Open
Abstract
The cytostatic agent hydroxyurea (HU) has proven to be beneficial for a variety of conditions in the disciplines of oncology, hematology, infectious disease and dermatology. It disrupts the S phase of the cell cycle by inhibiting the ribonucleotide reductase enzyme, thus blocking the transformation of ribonucleotides into deoxyribonucleotides, a rate limiting step in DNA synthesis. HU is listed as an essential medicine by the World Health Organization. Several studies have indicated that HU is well tolerated and safe in pregnant women and very young pediatric patients. To our knowledge, only a few controlled studies on the adverse effects of HU therapy have been done in humans. Despite this, the prevalence of central nervous system abnormalities, including ischemic lesions and stenosis have been reported. This review will summarize and present the effects of HU exposure on the prenatal and perinatal development of the rat cerebellar cortex and deep cerebellar nuclei neurons. Our results call for the necessity to better understand HU effects and define the administration of this drug to gestating women and young pediatric patients.
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Affiliation(s)
- Lucía Rodríguez-Vázquez
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.
| | - Joaquín Martí
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193 Barcelona, Spain.
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27
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Developmental pattern and structural factors of dendritic survival in cerebellar granule cells in vivo. Sci Rep 2018; 8:17561. [PMID: 30510282 PMCID: PMC6277421 DOI: 10.1038/s41598-018-35829-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 11/12/2018] [Indexed: 12/17/2022] Open
Abstract
Granule cells (GCs) in the cerebellar cortex are important for sparse encoding of afferent sensorimotor information. Modeling studies show that GCs can perform their function most effectively when they have four dendrites. Indeed, mature GCs have four short dendrites on average, each terminating in a claw-like ending that receives both excitatory and inhibitory inputs. Immature GCs, however, have significantly more dendrites—all without claws. How these redundant dendrites are refined during development is largely unclear. Here, we used in vivo time-lapse imaging and immunohistochemistry to study developmental refinement of GC dendritic arbors and its relation to synapse formation. We found that while the formation of dendritic claws stabilized the dendrites, the selection of surviving dendrites was made before claw formation, and longer immature dendrites had a significantly higher chance of survival than shorter dendrites. Using immunohistochemistry, we show that glutamatergic and GABAergic synapses are transiently formed on immature GC dendrites, and the number of GABAergic, but not glutamatergic, synapses correlates with the length of immature dendrites. Together, these results suggest a potential role of transient GABAergic synapses on dendritic selection and show that preselected dendrites are stabilized by the formation of dendritic claws—the site of mature synapses.
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Hydroxyurea Exposure and Development of the Cerebellar External Granular Layer: Effects on Granule Cell Precursors, Bergmann Glial and Microglial Cells. Neurotox Res 2018; 35:387-400. [PMID: 30276718 DOI: 10.1007/s12640-018-9964-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 12/20/2022]
Abstract
The current paper presents a histological analysis of the cell death in the cerebellar external granular layer (EGL) following the treatment with a single dose (2 mg/g) of hydroxyurea (HU). The rats were examined at postnatal days (P) 5, 10, and 15, and sacrificed at appropriate times ranging from 6 to 48 h after treatment administration. Studies were done in each cortical lobe (anterior, central, posterior, and inferior). The quantification of several parameters, such as density of 5-bromo-2'-deoxyuridine, TUNEL, vimentin, and tomato lectin-stained cells, revealed that HU compromises the viability of EGL cells. Our results indicate that P10 is a time of high vulnerability to injury. We also show here that the anterior and central lobes are the cortical regions most susceptible to the action of the HU. Additionally, our data also indicate that from 6 to 24 h after HU-exposure is a time-window of high sensibility to this agent. On the other hand, our ultrastructural analysis confirmed that HU administration produces the activation of apoptotic cellular events in the EGL, resulting in a substantial number of dying cells. Different stages of apoptosis can be observed in all cortical lobes at all investigated postnatal ages and survival times. Moreover, we observed that dying neuroblasts were covered by laminar processes of Bergmann glia, and that these unipolar astrocytes presented cytological features of phagocytes engulfing apoptotic bodies and cell debris. The electron microscopy study also revealed the participation of ameboid microglial cells in the phagocytosis of apoptotic cells in the regions of the EGL with extensive cell death.
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MARVELD1 depletion leads to dysfunction of motor and cognition via regulating glia-dependent neuronal migration during brain development. Cell Death Dis 2018; 9:999. [PMID: 30250269 PMCID: PMC6155261 DOI: 10.1038/s41419-018-1027-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 07/18/2018] [Indexed: 12/27/2022]
Abstract
The establishment of functional neuronal connectivity is dependent on the neuronal migration and the accurate positioning of neurons in the developing brain. Abnormal neuronal migration can trigger neuronal maturation defects and apoptosis. However, many genetic bases remain unclear in neuronal migration disorders during brain development. In this study, we reported that MARVELD1-defected mice displayed motor and cognitive dysfunction resulting from aberrant neuronal migration during brain development. The laminar organization of the cerebral cortex and cerebellum in MARVELD1 knockout (KO) mice is disrupted, indicating impaired radial neuronal migration. Furthermore, we used the cerebellum as a model to explore the radial neuronal migration processes, and the results demonstrated that the proper neuronal migration depended on MARVELD1 expression in glial cells of the developing brain. MARVELD1 suppressed the expression of ITGB1 and FAK Tyr397 phosphorylation in glia-dependent manner. The inhibition of the MARVELD1/ITGB1/FAK signalling pathway in MARVELD1 KO mice could reverse the defects in neuronal migration in vitro. Our findings revealed that MARVELD1 regulated neuronal migration by mediating the formation of glial fibres and ITGB1/FAK signalling pathway. The depletion of MARVELD1 during mouse brain development led to the abnormity of motor and cognition functions.
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30
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Momose-Sato Y, Sato K. Optical analysis of functional development of the facial motor nucleus in the embryonic rat brainstem. Eur J Neurosci 2018; 48:3273-3287. [PMID: 30118560 DOI: 10.1111/ejn.14122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/29/2018] [Accepted: 08/01/2018] [Indexed: 11/28/2022]
Abstract
Facial motor neurons of the rat embryo are first generated in rhombomere 4 and then migrate in the caudo-ventral direction. This migration forms a unique axonal trajectory called the genu, a loop of facial motor axons around the abducens nucleus. It is still unclear when and how this unique structure is functionally established during ontogenesis. Using voltage-sensitive dye (VSD) recording and the DiI staining method, we identified neural responses evoked by facial nerve (N.VII) stimulation and examined developmental processes of the facial motor nucleus in E12-E17 rat brainstems. We identified two types of fast spike-like signals; a long-duration signal, which corresponded to the action potential in the N.VII soma, and a short-duration signal, which reflected the action potential in the N.VII axons. The long-duration signal was detected as early as E13, suggesting that the N.VII motor neuron is already excitable at the beginning of cell migration. The response area of the long-duration signal extended caudally at E13-E14, and shifted in a ventral direction at E15. At E16-E17, the long-duration signal was concentrated in the caudo-ventral area, which was comparable to the location of the facial motor nucleus in the adult rat brainstem. These results demonstrate that developmental processes of cell migration and nuclear organization can be visualized and identified functionally with the VSD recording. We discuss the results by comparing functiogenesis and morphogenesis of the N.VII pathway.
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Affiliation(s)
- Yoko Momose-Sato
- Department of Nutrition and Dietetics, College of Nutrition, Kanto Gakuin University, Yokohama, Japan
| | - Katsushige Sato
- Department of Health and Nutrition Sciences, Faculty of Human Health, Komazawa Women's University, Tokyo, Japan
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31
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Single-cell trajectory analysis of human homogenous neurons carrying a rare RELN variant. Transl Psychiatry 2018; 8:129. [PMID: 30022058 PMCID: PMC6052151 DOI: 10.1038/s41398-018-0177-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/08/2018] [Indexed: 11/08/2022] Open
Abstract
Reelin is a protein encoded by the RELN gene that controls neuronal migration in the developing brain. Human genetic studies suggest that rare RELN variants confer susceptibility to mental disorders such as schizophrenia. However, it remains unknown what effects rare RELN variants have on human neuronal cells. To this end, the analysis of human neuronal dynamics at the single-cell level is necessary. In this study, we generated human-induced pluripotent stem cells carrying a rare RELN variant (RELN-del) using targeted genome editing; cells were further differentiated into highly homogeneous dopaminergic neurons. Our results indicated that RELN-del triggered an impaired reelin signal and decreased the expression levels of genes relevant for cell movement in human neurons. Single-cell trajectory analysis revealed that control neurons possessed directional migration even in vitro, while RELN-del neurons demonstrated a wandering type of migration. We further confirmed these phenotypes in neurons derived from a patient carrying the congenital RELN-del. To our knowledge, this is the first report of the biological significance of a rare RELN variant in human neurons based on individual neuron dynamics. Collectively, our approach should be useful for studying reelin function and evaluating mental disorder susceptibility, focusing on individual human neuronal migration.
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32
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The RacGAP β-Chimaerin is essential for cerebellar granule cell migration. Sci Rep 2018; 8:680. [PMID: 29330522 PMCID: PMC5766509 DOI: 10.1038/s41598-017-19116-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 12/21/2017] [Indexed: 11/08/2022] Open
Abstract
During mammalian cerebellar development, postnatal granule cell progenitors proliferate in the outer part of the External Granule Layer (EGL). Postmitotic granule progenitors migrate tangentially in the inner EGL before switching to migrate radially inward, past the Purkinje cell layer, to achieve their final position in the mature Granule Cell Layer (GCL). Here, we show that the RacGAP β-chimaerin is expressed by a small population of late-born, premigratory granule cells. β-chimaerin deficiency causes a subset of granule cells to become arrested in the EGL, where they differentiate and form ectopic neuronal clusters. These clusters of granule cells are able to recruit aberrantly projecting mossy fibers. Collectively, these data suggest a role for β-chimaerin as an intracellular mediator of Cerebellar Granule Cell radial migration.
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33
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Sakamoto I, Ueyama T, Hayashibe M, Nakamura T, Mohri H, Kiyonari H, Shigyo M, Tohda C, Saito N. Roles of Cdc42 and Rac in Bergmann glia during cerebellar corticogenesis. Exp Neurol 2017; 302:57-67. [PMID: 29253508 DOI: 10.1016/j.expneurol.2017.12.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 11/18/2017] [Accepted: 12/13/2017] [Indexed: 10/18/2022]
Abstract
Bergmann glia (BG) are important in the inward type of radial migration of cerebellar granule neurons (CGNs). However, details regarding the functions of Cdc42 and Rac in BG for radial migration of CGN are unknown. To examine the roles of Cdc42 and Rac in BG during cerebellar corticogenesis, mice with a single deletion of Cdc42 or Rac1 and those with double deletions of Cdc42 and Rac1 under control of the glial fibrillary acidic protein (GFAP) promoter: GFAP-Cre;Cdc42flox/flox (Cdc42-KO), GFAP-Cre;Rac1flox/flox (Rac1-KO), and GFAP-Cre; Cdc42flox/flox;Rac1flox/flox (Cdc42/Rac1-DKO) mice, were generated. Both Cdc42-KO and Rac1-KO mice, but more obviously Cdc42-KO mice, had disturbed alignment of BG in the Purkinje cell layer (PCL). We found that Cdc42-KO, but not Rac1-KO, induced impaired radial migration of CGNs in the late phase of radial migration, leading to retention of CGNs in the lower half of the molecular layer (ML). Cdc42-KO, but not Rac1-KO, mice also showed aberrantly aligned Purkinje cells (PCs). These phenotypes were exacerbated in Cdc42/Rac1-DKO mice. Alignment of BG radial fibers in the ML and BG endfeet at the pial surface of the cerebellum evaluated by GFAP staining was disturbed and weak in Cdc42/Rac1-DKO mice, respectively. Our data indicate that Cdc42 and Rac, but predominantly Cdc42, in BG play important roles during the late phase of radial migration of CGNs. We also report here that Cdc42 is involved in gliophilic migration of CGNs, in contrast to Rac, which is more closely connected to regulating neurophilic migration.
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Affiliation(s)
- Isao Sakamoto
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Takehiko Ueyama
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan.
| | - Masakazu Hayashibe
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Takashi Nakamura
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Hiroaki Mohri
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Hiroshi Kiyonari
- Animal Resource Development Unit and Genetic Engineering Team, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan
| | - Michiko Shigyo
- Division of Neuromedical Science, Department of Bioscience, Institute of Natural Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Chihiro Tohda
- Division of Neuromedical Science, Department of Bioscience, Institute of Natural Medicine, University of Toyama, Toyama 930-0194, Japan
| | - Naoaki Saito
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan.
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Nakamura T, Ueyama T, Ninoyu Y, Sakaguchi H, Choijookhuu N, Hishikawa Y, Kiyonari H, Kohta M, Sakahara M, de Curtis I, Kohmura E, Hisa Y, Aiba A, Saito N. Novel role of Rac-Mid1 signaling in medial cerebellar development. Development 2017; 144:1863-1875. [PMID: 28512198 DOI: 10.1242/dev.147900] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/31/2017] [Indexed: 02/04/2023]
Abstract
Rac signaling impacts a relatively large number of downstream targets; however, few studies have established an association between Rac pathways and pathological conditions. In the present study, we generated mice with double knockout of Rac1 and Rac3 (Atoh1-Cre;Rac1flox/flox;Rac3-/- ) in cerebellar granule neurons (CGNs). We observed impaired tangential migration at E16.5, as well as numerous apoptotic CGNs at the deepest layer of the external granule layer (EGL) in the medial cerebellum of Atoh1-Cre;Rac1flox/flox;Rac3-/- mice at P8. Atoh1-Cre;Rac1flox/flox;Rac3-/- CGNs differentiated normally until expression of p27kip1 and NeuN in the deep EGL at P5. Primary CGNs and cerebellar microexplants from Atoh1-Cre;Rac1flox/flox;Rac3-/- mice exhibited impaired neuritogenesis, which was more apparent in Map2-positive dendrites. Such findings suggest that impaired tangential migration and final differentiation of CGNs have resulted in decreased cerebellum size and agenesis of the medial internal granule layer, respectively. Furthermore, Rac depleted/deleted cells exhibited decreased levels of Mid1 and impaired mTORC1 signaling. Mid1 depletion in CGNs produced mild impairments in neuritogenesis and reductions in mTORC1 signaling. Thus, a novel Rac-signaling pathway (Rac1-Mid1-mTORC1) may be involved in medial cerebellar development.
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Affiliation(s)
- Takashi Nakamura
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan.,Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Takehiko Ueyama
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Yuzuru Ninoyu
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
| | - Hirofumi Sakaguchi
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Narantsog Choijookhuu
- Division of Histochemistry and Cell Biology, Department of Anatomy, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
| | - Yoshitaka Hishikawa
- Division of Histochemistry and Cell Biology, Department of Anatomy, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
| | - Hiroshi Kiyonari
- Animal Resource Development Unit and Genetic Engineering Team, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan
| | - Masaaki Kohta
- Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Mizuho Sakahara
- Department of Molecular Genetics, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Ivan de Curtis
- Division of Neuroscience, San Raffaele Scientific Institute, Milano 20132, Italy
| | - Eiji Kohmura
- Department of Neurosurgery, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Yasuo Hisa
- Department of Otolaryngology-Head and Neck Surgery, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan
| | - Atsu Aiba
- Department of Molecular Genetics, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan.,Laboratory of Animal Resources, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Naoaki Saito
- Laboratory of Molecular Pharmacology, Biosignal Research Center, Kobe University, Kobe 657-8501, Japan
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35
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Benon A, Ya C, Martin L, Watrin C, Chounlamountri N, Jaaoini I, Honnorat J, Pellier-Monnin V, Noraz N. The Syk kinases orchestrate cerebellar granule cell tangential migration. Neuroscience 2017; 360:230-239. [DOI: 10.1016/j.neuroscience.2017.07.057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 07/21/2017] [Accepted: 07/21/2017] [Indexed: 01/03/2023]
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36
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Molina V, Rodríguez-Vázquez L, Owen D, Valero O, Martí J. Cell cycle analysis in the rat external granular layer evaluated by several bromodeoxyuridine immunoperoxidase staining protocols. Histochem Cell Biol 2017; 148:477-488. [PMID: 28681271 DOI: 10.1007/s00418-017-1593-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/01/2017] [Indexed: 10/19/2022]
Abstract
An important step in bromodeoxyuridine (BrdU) immunohistochemistry is the production of single-stranded DNA to make the incorporated BrdU accessible to the antibodies. This paper examines the effect of distinct DNA denaturation pretreatments (DNase I, sodium citrate buffer, endonuclease Eco RI and exonuclease III, and HCl hydrolysis) on detection of BrdU. We found that all the methods used in the partial denaturation of DNA combined good nuclear immunostaining with acceptable tissue integrity. We also observed that these immunohistochemical protocols revealed a spatial pattern in the distribution of DNA-synthesizing cells within the cerebellar external granular layer (EGL) of 10-day-old rats, allowing us to estimate the fraction of S-phase cells. Our results indicate that detection of BrdU-stained cells is affected by the distinct histological procedures used in such detection. Additionally, as the duration and phases of the cell cycle in EGL neuroblasts are estimated in accordance with BrdU detection, an effect on this detection can render the measurement of cell cycle inaccurate. The present work shows that DNase I and citrate buffer, at appropriate conditions, may be good alternatives for acid denaturation. However, they are less sensitive than autoradiographic techniques that use 3H-thymidine administration. Finally, current data reveal that short survival times after a single BrdU exposure do not seem to affect the cell cycle progression of the EGL neuroblasts.
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Affiliation(s)
- Vanesa Molina
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Lucía Rodríguez-Vázquez
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - David Owen
- Departament de Filologia Anglesa i de Germanística, Àrea de Filologia Anglesa, Bellaterra, 08193, Barcelona, Spain
| | - Oliver Valero
- Servei d'Estadística Aplicada, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Joaquín Martí
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain.
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37
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Martí J, Molina V, Santa-Cruz MC, Hervás JP. Developmental Injury to the Cerebellar Cortex Following Hydroxyurea Treatment in Early Postnatal Life: An Immunohistochemical and Electron Microscopic Study. Neurotox Res 2016; 31:187-203. [PMID: 27601242 DOI: 10.1007/s12640-016-9666-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 08/17/2016] [Accepted: 08/30/2016] [Indexed: 11/30/2022]
Abstract
Postnatal development of the cerebellar cortex was studied in rats administered with a single dose (2 mg/g) of the cytotoxic agent hydroxyurea (HU) on postnatal day (P) 9 and collected at appropriate times ranging from 6 h to 45 days. Quantification of several parameters such as the density of pyknotic, mitotic, BrdU-positive, and vimentin-stained cells revealed that HU compromises the survival of the external granular layer (EGL) cells. Moreover, vimentin immunocytochemistry revealed overexpression and thicker immunoreactive glial processes in HU-treated rats. On the other hand, we also show that HU leads to the activation of apoptotic cellular events, resulting in a substantial number of dying EGL cells, as revealed by TUNEL staining and at the electron microscope level. Additionally, we quantified several features of the cerebellar cortex of rats exposed to HU in early postnatal life and collected in adulthood. Data analysis indicated that the analyzed parameters were less pronounced in rats administered with this agent. Moreover, we observed several alterations in the cerebellar cortex cytoarchitecture of rats injected with HU. Anomalies included ectopic placement of Purkinje cells and abnormities in the dendritic arbor of these macroneurons. Ectopic granule cells were also found in the molecular layer. These findings provide a clue for investigating the mechanisms of HU-induced toxicity during the development of the central nervous system. Our results also suggest that it is essential to avoid underestimating the adverse effects of this hydroxylated analog of urea when administered during early postnatal life.
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Affiliation(s)
- Joaquín Martí
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain.
| | - Vanesa Molina
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - M C Santa-Cruz
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - José P Hervás
- Unidad de Citología e Histología, Facultad de Biociencias, Universidad Autónoma de Barcelona, Bellaterra, 08193, Barcelona, Spain
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38
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Tharmalingam S, Hampson DR. The Calcium-Sensing Receptor and Integrins in Cellular Differentiation and Migration. Front Physiol 2016; 7:190. [PMID: 27303307 PMCID: PMC4880553 DOI: 10.3389/fphys.2016.00190] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 05/11/2016] [Indexed: 12/12/2022] Open
Abstract
The calcium-sensing receptor (CaSR) is a widely expressed homodimeric G-protein coupled receptor structurally related to the metabotropic glutamate receptors and GPRC6A. In addition to its well characterized role in maintaining calcium homeostasis and regulating parathyroid hormone release, evidence has accumulated linking the CaSR with cellular differentiation and migration, brain development, stem cell engraftment, wound healing, and tumor growth and metastasis. Elevated expression of the CaSR in aggressive metastatic tumors has been suggested as a potential novel prognostic marker for predicting metastasis, especially to bone tissue where extracellular calcium concentrations may be sufficiently high to activate the receptor. Recent evidence supports a model whereby CaSR-mediated activation of integrins promotes cellular migration. Integrins are single transmembrane spanning heterodimeric adhesion receptors that mediate cell migration by binding to extracellular matrix proteins. The CaSR has been shown to form signaling complexes with the integrins to facilitate both the movement and differentiation of cells, such as neurons during normal brain development and tumor cells under pathological circumstances. Thus, CaSR/integrin complexes may function as a universal cell migration or homing complex. Manipulation of this complex may be of potential interest for treating metastatic cancers, and for developmental disorders pertaining to aberrant neuronal migration.
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Affiliation(s)
| | - David R Hampson
- Pharmaceutical Sciences, University of Toronto Toronto, ON, Canada
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39
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Singh S, Howell D, Trivedi N, Kessler K, Ong T, Rosmaninho P, Raposo AA, Robinson G, Roussel MF, Castro DS, Solecki DJ. Zeb1 controls neuron differentiation and germinal zone exit by a mesenchymal-epithelial-like transition. eLife 2016; 5. [PMID: 27178982 PMCID: PMC4891180 DOI: 10.7554/elife.12717] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 05/03/2016] [Indexed: 12/13/2022] Open
Abstract
In the developing mammalian brain, differentiating neurons mature morphologically via neuronal polarity programs. Despite discovery of polarity pathways acting concurrently with differentiation, it's unclear how neurons traverse complex polarity transitions or how neuronal progenitors delay polarization during development. We report that zinc finger and homeobox transcription factor-1 (Zeb1), a master regulator of epithelial polarity, controls neuronal differentiation by transcriptionally repressing polarity genes in neuronal progenitors. Necessity-sufficiency testing and functional target screening in cerebellar granule neuron progenitors (GNPs) reveal that Zeb1 inhibits polarization and retains progenitors in their germinal zone (GZ). Zeb1 expression is elevated in the Sonic Hedgehog (SHH) medulloblastoma subgroup originating from GNPs with persistent SHH activation. Restored polarity signaling promotes differentiation and rescues GZ exit, suggesting a model for future differentiative therapies. These results reveal unexpected parallels between neuronal differentiation and mesenchymal-to-epithelial transition and suggest that active polarity inhibition contributes to altered GZ exit in pediatric brain cancers. DOI:http://dx.doi.org/10.7554/eLife.12717.001 During the formation of the brain, developing neurons are faced with a logistical problem. After newborn neurons form they must change in shape and move to their final location in the brain. Despite much speculation, little is known about these processes. Neurons mature via the activity of several pathways that control the activity, or expression, of the neuron’s genes. One way of controlling such gene expression is through proteins called transcription factors. At the same time, the developing neurons go through a process called polarization, where different regions of the cell develop different characteristics. However, it was not known how the maturation and polarization processes are linked, or how the developing neurons actively regulate polarization. By studying the developing mouse brain, Singh et al. found that a transcription factor called Zeb1 keeps neurons in a immature state, stopping them from becoming polarized. Further investigation revealed that Zeb1 does this by preventing the production of a group of proteins that helps to polarize the cells. The most common type of malignant brain tumour in children is called a medulloblastoma. Singh et al. analyzed the genes expressed in mice that have a type of medulloblastoma that results from the constant activity of a gene called Sonic Hedgehog in developing neurons. This revealed that these tumour cells contain abnormally high levels of Zeb1, and so do not take on a polarized form. However, artificially restoring other factors that encourage the cells to polarize caused the neurons to mature normally. Further investigation is now needed to find out whether the activity of the Sonic Hedgehog gene regulates Zeb1 activity, and to discover whether inhibiting Zeb1 could prevent brain tumours from developing. DOI:http://dx.doi.org/10.7554/eLife.12717.002
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Affiliation(s)
- Shalini Singh
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, United States
| | - Danielle Howell
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, United States
| | - Niraj Trivedi
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, United States
| | | | - Taren Ong
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, United States
| | - Pedro Rosmaninho
- Department of Molecular Neurobiology, Instituto Gulbenkian de Ciência Oeiras, Oeiras, Portugal
| | - Alexandre Asf Raposo
- Department of Molecular Neurobiology, Instituto Gulbenkian de Ciência Oeiras, Oeiras, Portugal
| | - Giles Robinson
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, United States
| | - Martine F Roussel
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, United States
| | - Diogo S Castro
- Department of Molecular Neurobiology, Instituto Gulbenkian de Ciência Oeiras, Oeiras, Portugal
| | - David J Solecki
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, United States
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Hanzel M, Wingate RJT, Butts T. Ex Vivo Culture of Chick Cerebellar Slices and Spatially Targeted Electroporation of Granule Cell Precursors. J Vis Exp 2015:e53421. [PMID: 26709704 DOI: 10.3791/53421] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The cerebellar external granule layer (EGL) is the site of the largest transit amplification in the developing brain, and an excellent model for studying neuronal proliferation and differentiation. In addition, evolutionary modifications of its proliferative capability have been responsible for the dramatic expansion of cerebellar size in the amniotes, making the cerebellum an excellent model for evo-devo studies of the vertebrate brain. The constituent cells of the EGL, cerebellar granule progenitors, also represent a significant cell of origin for medulloblastoma, the most prevalent paediatric neuronal tumour. Following transit amplification, granule precursors migrate radially into the internal granular layer of the cerebellum where they represent the largest neuronal population in the mature mammalian brain. In chick, the peak of EGL proliferation occurs towards the end of the second week of gestation. In order to target genetic modification to this layer at the peak of proliferation, we have developed a method for genetic manipulation through ex vivo electroporation of cerebellum slices from embryonic Day 14 chick embryos. This method recapitulates several important aspects of in vivo granule neuron development and will be useful in generating a thorough understanding of cerebellar granule cell proliferation and differentiation, and thus of cerebellum development, evolution and disease.
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Affiliation(s)
| | | | - Thomas Butts
- School of Biological and Chemical Sciences, Queen Mary, University of London;
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41
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Legué E, Riedel E, Joyner AL. Clonal analysis reveals granule cell behaviors and compartmentalization that determine the folded morphology of the cerebellum. Development 2015; 142:1661-71. [PMID: 25834018 DOI: 10.1242/dev.120287] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 03/09/2015] [Indexed: 11/20/2022]
Abstract
The mammalian cerebellum consists of folds of different sizes and shapes that house distinct neural circuits. A crucial factor underlying foliation is the generation of granule cells (gcs), the most numerous neuron type in the brain. We used clonal analysis to uncover global as well as folium size-specific cellular behaviors that underlie cerebellar morphogenesis. Unlike most neural precursors, gc precursors divide symmetrically, accounting for their massive expansion. We found that oriented cell divisions underlie an overall anteroposteriorly polarized growth of the cerebellum and gc clone geometry. Clone geometry is further refined by mediolateral oriented migration and passive dispersion of differentiating gcs. Most strikingly, the base of each fissure acts as a boundary for gc precursor dispersion, which we propose allows each folium to be regulated as a developmental unit. Indeed, the geometry and size of clones in long and short folia are distinct. Moreover, in engrailed 1/2 mutants with shorter folia, clone cell number and geometry are most similar to clones in short folia of wild-type mice. Thus, the cerebellum has a modular mode of development that allows the plane of cell division and number of divisions to be differentially regulated to ensure that the appropriate number of cells are partitioned into each folium.
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Affiliation(s)
- Emilie Legué
- Department of Developmental Biology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Elyn Riedel
- Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Alexandra L Joyner
- Department of Developmental Biology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
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42
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Cunningham D, DeBarber AE, Bir N, Binkley L, Merkens LS, Steiner RD, Herman GE. Analysis of hedgehog signaling in cerebellar granule cell precursors in a conditional Nsdhl allele demonstrates an essential role for cholesterol in postnatal CNS development. Hum Mol Genet 2015; 24:2808-25. [PMID: 25652406 DOI: 10.1093/hmg/ddv042] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 02/02/2015] [Indexed: 12/21/2022] Open
Abstract
NSDHL is a 3β-hydroxysterol dehydrogenase that is involved in the removal of two C-4 methyl groups in one of the later steps of cholesterol biosynthesis. Mutations in the gene encoding the enzyme are responsible for the X-linked, male lethal mouse mutations bare patches and striated, as well as most cases of human CHILD syndrome. Rare, hypomorphic NSDHL mutations are also associated with X-linked intellectual disability in males with CK syndrome. Since hemizygous male mice with Nsdhl mutations die by midgestation, we generated a conditional targeted Nsdhl mutation (Nsdhl(tm1.1Hrm)) to investigate the essential role of cholesterol in the early postnatal CNS. Ablation of Nsdhl in radial glia using GFAP-cre resulted in live-born, normal appearing affected male pups. However, the pups develop overt ataxia by postnatal day 8-10 and die shortly thereafter. Histological abnormalities include progressive loss of cortical and hippocampal neurons, as well as deficits in the proliferation and migration of cerebellar granule precursors and subsequent massive apoptosis of the cerebellar cortex. We replicated the granule cell precursor proliferation defect in vitro and demonstrate that it results from defective signaling by SHH. Furthermore, this defect is almost completely rescued by supplementation of the culture media with exogenous cholesterol, while methylsterol accumulation above the enzymatic block appears to be associated with increased cell death. These data support the absolute requirement for cholesterol synthesis in situ once the blood-brain-barrier forms and cholesterol transport to the fetus is abolished. They further emphasize the complex ramifications of cholesterogenic enzyme deficiency on cellular metabolism.
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Affiliation(s)
- David Cunningham
- Center for Molecular and Human Genetics, The Research Institute at Nationwide Children's Hospital and Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | | | - Natalie Bir
- Center for Molecular and Human Genetics, The Research Institute at Nationwide Children's Hospital and Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | - Laura Binkley
- Center for Molecular and Human Genetics, The Research Institute at Nationwide Children's Hospital and Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | | | - Robert D Steiner
- Department of Pediatrics, Department of Molecular and Medical Genetics and Institute on Development and Disability, Doernbecher Children's Hospital, Oregon Health & Science University, Portland, OR, USA and Marshfield Clinic Research Foundation and the Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Marshfield and Madison, WI, USA
| | - Gail E Herman
- Center for Molecular and Human Genetics, The Research Institute at Nationwide Children's Hospital and Department of Pediatrics, The Ohio State University, Columbus, OH, USA,
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43
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Anckar J, Bonni A. Regulation of neuronal morphogenesis and positioning by ubiquitin-specific proteases in the cerebellum. PLoS One 2015; 10:e0117076. [PMID: 25607801 PMCID: PMC4301861 DOI: 10.1371/journal.pone.0117076] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/19/2014] [Indexed: 11/19/2022] Open
Abstract
Ubiquitin signaling mechanisms play fundamental roles in the cell-intrinsic control of neuronal morphogenesis and connectivity in the brain. However, whereas specific ubiquitin ligases have been implicated in key steps of neural circuit assembly, the roles of ubiquitin-specific proteases (USPs) in the establishment of neuronal connectivity have remained unexplored. Here, we report a comprehensive analysis of USP family members in granule neuron morphogenesis and positioning in the rodent cerebellum. We identify a set of 32 USPs that are expressed in granule neurons. We also characterize the subcellular localization of the 32 USPs in granule neurons using a library of expression plasmids encoding GFP-USPs. In RNAi screens of the 32 neuronally expressed USPs, we uncover novel functions for USP1, USP4, and USP20 in the morphogenesis of granule neuron dendrites and axons and we identify a requirement for USP30 and USP33 in granule neuron migration in the rodent cerebellar cortex in vivo. These studies reveal that specific USPs with distinct spatial localizations harbor key functions in the control of neuronal morphogenesis and positioning in the mammalian cerebellum, with important implications for our understanding of the cell-intrinsic mechanisms that govern neural circuit assembly in the brain.
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Affiliation(s)
- Julius Anckar
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Azad Bonni
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St Louis, Missouri, United States of America
- * E-mail:
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44
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Marzban H, Del Bigio MR, Alizadeh J, Ghavami S, Zachariah RM, Rastegar M. Cellular commitment in the developing cerebellum. Front Cell Neurosci 2015; 8:450. [PMID: 25628535 PMCID: PMC4290586 DOI: 10.3389/fncel.2014.00450] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 12/12/2014] [Indexed: 12/11/2022] Open
Abstract
The mammalian cerebellum is located in the posterior cranial fossa and is critical for motor coordination and non-motor functions including cognitive and emotional processes. The anatomical structure of cerebellum is distinct with a three-layered cortex. During development, neurogenesis and fate decisions of cerebellar primordium cells are orchestrated through tightly controlled molecular events involving multiple genetic pathways. In this review, we will highlight the anatomical structure of human and mouse cerebellum, the cellular composition of developing cerebellum, and the underlying gene expression programs involved in cell fate commitments in the cerebellum. A critical evaluation of the cell death literature suggests that apoptosis occurs in ~5% of cerebellar cells, most shortly after mitosis. Apoptosis and cellular autophagy likely play significant roles in cerebellar development, we provide a comprehensive discussion of their role in cerebellar development and organization. We also address the possible function of unfolded protein response in regulation of cerebellar neurogenesis. We discuss recent advancements in understanding the epigenetic signature of cerebellar compartments and possible connections between DNA methylation, microRNAs and cerebellar neurodegeneration. Finally, we discuss genetic diseases associated with cerebellar dysfunction and their role in the aging cerebellum.
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Affiliation(s)
- Hassan Marzban
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Marc R Del Bigio
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada ; Department of Pathology, University of Manitoba Winnipeg, MB, Canada
| | - Javad Alizadeh
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, University of Manitoba Winnipeg, MB, Canada
| | - Robby M Zachariah
- Department of Biochemistry and Medical Genetics, University of Manitoba Winnipeg, MB, Canada ; Regenerative Medicine Program, University of Manitoba Winnipeg, MB, Canada
| | - Mojgan Rastegar
- Department of Biochemistry and Medical Genetics, University of Manitoba Winnipeg, MB, Canada ; Regenerative Medicine Program, University of Manitoba Winnipeg, MB, Canada
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Butts T, Green MJ, Wingate RJT. Development of the cerebellum: simple steps to make a 'little brain'. Development 2014; 141:4031-41. [PMID: 25336734 DOI: 10.1242/dev.106559] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The cerebellum is a pre-eminent model for the study of neurogenesis and circuit assembly. Increasing interest in the cerebellum as a participant in higher cognitive processes and as a locus for a range of disorders and diseases make this simple yet elusive structure an important model in a number of fields. In recent years, our understanding of some of the more familiar aspects of cerebellar growth, such as its territorial allocation and the origin of its various cell types, has undergone major recalibration. Furthermore, owing to its stereotyped circuitry across a range of species, insights from a variety of species have contributed to an increasingly rich picture of how this system develops. Here, we review these recent advances and explore three distinct aspects of cerebellar development - allocation of the cerebellar anlage, the significance of transit amplification and the generation of neuronal diversity - each defined by distinct regulatory mechanisms and each with special significance for health and disease.
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Affiliation(s)
- Thomas Butts
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK School of Biological and Chemical Sciences, Queen Mary, University of London, London E1 4NS, UK
| | - Mary J Green
- National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Richard J T Wingate
- MRC Centre for Developmental Neurobiology, King's College London, London SE1 1UL, UK
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46
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Kullmann JA, Wickertsheim I, Minnerup L, Costell M, Friauf E, Rust MB. Profilin1 activity in cerebellar granule neurons is required for radial migration in vivo. Cell Adh Migr 2014; 9:247-53. [PMID: 25495756 DOI: 10.4161/19336918.2014.983804] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Neuron migration defects are an important aspect of human neuropathies. The underlying molecular mechanisms of such migration defects are largely unknown. Actin dynamics has been recognized as an important determinant of neuronal migration, and we recently found that the actin-binding protein profilin1 is relevant for radial migration of cerebellar granule neurons (CGN). As the exploited brain-specific mutants lacked profilin1 in both neurons and glial cells, it remained unknown whether profilin1 activity in CGN is relevant for CGN migration in vivo. To test this, we capitalized on a transgenic mouse line that expresses a tamoxifen-inducible Cre variant in CGN, but no other cerebellar cell type. In these profilin1 mutants, the cell density was elevated in the molecular layer, and ectopic CGN occurred. Moreover, 5-bromo-2'-deoxyuridine tracing experiments revealed impaired CGN radial migration. Hence, our data demonstrate the cell autonomous role of profilin1 activity in CGN for radial migration.
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Key Words
- BrdU+, BrdU-positive
- BrdU, 5-bromo-2′-deoxyuridine
- CGN, cerebellar granule neurons
- CaMKIV, Ca2+/calmodulin-dependent protein kinase IV
- EGL, external granule cell layer
- IGL, internal granule cell layer
- ML, molecular layer
- Math1-Cre, Math1-mediated Cre expression
- NeuN, neuron-specific nuclear protein
- P, postnatal day
- PI, propidium iodide.
- Pfn1, profilin1
- actin dynamics
- actin treadmilling
- actin-binding protein
- cerebellar cortex
- cerebellar development
- cerebellar granule neurons
- cerebellum
- neuronal migration
- profilin
- radial migration
- βGal+, βGal-positive
- βGal, β-galactosidase
- βGal−, βGal-negative
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Affiliation(s)
- Jan A Kullmann
- a Neurobiology/Neurophysiology Group ; University of Kaiserslautern ; Kaiserslautern , Germany
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47
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Renaud J, Chédotal A. Time-lapse analysis of tangential migration in Sema6A and PlexinA2 knockouts. Mol Cell Neurosci 2014; 63:49-59. [DOI: 10.1016/j.mcn.2014.09.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 08/08/2014] [Accepted: 09/12/2014] [Indexed: 10/24/2022] Open
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Elston GN, Fujita I. Pyramidal cell development: postnatal spinogenesis, dendritic growth, axon growth, and electrophysiology. Front Neuroanat 2014; 8:78. [PMID: 25161611 PMCID: PMC4130200 DOI: 10.3389/fnana.2014.00078] [Citation(s) in RCA: 109] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 07/22/2014] [Indexed: 01/12/2023] Open
Abstract
Here we review recent findings related to postnatal spinogenesis, dendritic and axon growth, pruning and electrophysiology of neocortical pyramidal cells in the developing primate brain. Pyramidal cells in sensory, association and executive cortex grow dendrites, spines and axons at different rates, and vary in the degree of pruning. Of particular note is the fact that pyramidal cells in primary visual area (V1) prune more spines than they grow during postnatal development, whereas those in inferotemporal (TEO and TE) and granular prefrontal cortex (gPFC; Brodmann's area 12) grow more than they prune. Moreover, pyramidal cells in TEO, TE and the gPFC continue to grow larger dendritic territories from birth into adulthood, replete with spines, whereas those in V1 become smaller during this time. The developmental profile of intrinsic axons also varies between cortical areas: those in V1, for example, undergo an early proliferation followed by pruning and local consolidation into adulthood, whereas those in area TE tend to establish their territory and consolidate it into adulthood with little pruning. We correlate the anatomical findings with the electrophysiological properties of cells in the different cortical areas, including membrane time constant, depolarizing sag, duration of individual action potentials, and spike-frequency adaptation. All of the electrophysiological variables ramped up before 7 months of age in V1, but continued to ramp up over a protracted period of time in area TE. These data suggest that the anatomical and electrophysiological profiles of pyramidal cells vary among cortical areas at birth, and continue to diverge into adulthood. Moreover, the data reveal that the “use it or lose it” notion of synaptic reinforcement may speak to only part of the story, “use it but you still might lose it” may be just as prevalent in the cerebral cortex.
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Affiliation(s)
- Guy N Elston
- Centre for Cognitive Neuroscience Sunshine Coast, QLD, Australia
| | - Ichiro Fujita
- Graduate School of Frontier Biosciences and Center for Information and Neural Networks, Osaka University and National Institute of Communication Technology Suita, Japan
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49
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Benitez SG, Castro AE, Patterson SI, Muñoz EM, Seltzer AM. Hypoxic preconditioning differentially affects GABAergic and glutamatergic neuronal cells in the injured cerebellum of the neonatal rat. PLoS One 2014; 9:e102056. [PMID: 25032984 PMCID: PMC4102512 DOI: 10.1371/journal.pone.0102056] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 06/13/2014] [Indexed: 12/13/2022] Open
Abstract
In this study we examined cerebellar alterations in a neonatal rat model of hypoxic-ischemic brain injury with or without hypoxic preconditioning (Pc). Between postnatal days 7 and 15, the cerebellum is still undergoing intense cellular proliferation, differentiation and migration, dendritogenesis and synaptogenesis. The expression of glutamate decarboxylase 1 (GAD67) and the differentiation factor NeuroD1 were examined as markers of Purkinje and granule cells, respectively. We applied quantitative immunohistochemistry to sagittal cerebellar slices, and Western blot analysis of whole cerebella obtained from control (C) rats and rats submitted to Pc, hypoxia-ischemia (L) and a combination of both treatments (PcL). We found that either hypoxia-ischemia or Pc perturbed the granule cells in the posterior lobes, affecting their migration and final placement in the internal granular layer. These effects were partially attenuated when the Pc was delivered prior to the hypoxia-ischemia. Interestingly, whole nuclear NeuroD1 levels in Pc animals were comparable to those in the C rats. However, a subset of Purkinje cells that were severely affected by the hypoxic-ischemic insult—showing signs of neuronal distress at the levels of the nucleus, cytoplasm and dendritic arborization—were not protected by Pc. A monoclonal antibody specific for GAD67 revealed a three-band pattern in cytoplasmic extracts from whole P15 cerebella. A ∼110 kDa band, interpreted as a potential homodimer of a truncated form of GAD67, was reduced in Pc and L groups while its levels were close to the control animals in PcL rats. Additionally we demonstrated differential glial responses depending on the treatment, including astrogliosis in hypoxiated cerebella and a selective effect of hypoxia-ischemia on the vimentin-immunolabeled intermediate filaments of the Bergmann glia. Thus, while both glutamatergic and GABAergic cerebellar neurons are compromised by the hypoxic-ischemic insult, the former are protected by a preconditioning hypoxia while the latter are not.
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Affiliation(s)
- Sergio G Benitez
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Analía E Castro
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Sean I Patterson
- Traumatic and Toxic Lesions in the Nervous System Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Estela M Muñoz
- Laboratory of Neurobiology: Chronobiology Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
| | - Alicia M Seltzer
- Neonatal Brain Development Section, Institute of Histology and Embryology of Mendoza (IHEM), School of Medicine, National University of Cuyo, Mendoza, National Scientific and Technical Research Council (CONICET), National Agency for Scientific and Technological Promotion (ANPCyT), Mendoza, Argentina
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Radial Glia, the Keystone of the Development of the Hippocampal Dentate Gyrus. Mol Neurobiol 2014; 51:131-41. [DOI: 10.1007/s12035-014-8692-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/24/2014] [Indexed: 01/20/2023]
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