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Krishnamurthy A, Lee AS, Bayin NS, Stephen DN, Nasef O, Lao Z, Joyner AL. Engrailed transcription factors direct excitatory cerebellar neuron diversity and survival. Development 2024; 151:dev202502. [PMID: 38912572 DOI: 10.1242/dev.202502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 06/17/2024] [Indexed: 06/25/2024]
Abstract
The neurons of the three cerebellar nuclei (CN) are the primary output neurons of the cerebellum. The excitatory neurons (e) of the medial (m) CN (eCNm) were recently divided into molecularly defined subdomains in the adult; however, how they are established during development is not known. We define molecular subdomains of the mouse embryonic eCNm using single-cell RNA-sequencing and spatial expression analysis, showing that they evolve during embryogenesis to prefigure the adult. Furthermore, eCNm are transcriptionally divergent from cells in the other nuclei by embryonic day 14.5. We previously showed that loss of the homeobox genes En1 and En2 leads to loss of approximately half of the embryonic eCNm. We demonstrate that mutation of En1/2 in the embryonic eCNm results in death of specific posterior eCNm molecular subdomains and downregulation of TBR2 (EOMES) in an anterior embryonic subdomain, as well as reduced synaptic gene expression. We further reveal a similar function for EN1/2 in mediating TBR2 expression, neuron differentiation and survival in the other excitatory neurons (granule and unipolar brush cells). Thus, our work defines embryonic eCNm molecular diversity and reveals conserved roles for EN1/2 in the cerebellar excitatory neuron lineage.
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Affiliation(s)
- Anjana Krishnamurthy
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA
| | - Andrew S Lee
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA
| | - N Sumru Bayin
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
| | - Daniel N Stephen
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
| | - Olivia Nasef
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
| | - Zhimin Lao
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
| | - Alexandra L Joyner
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA
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Lee AS, Arefin TM, Gubanova A, Stephen DN, Liu Y, Lao Z, Krishnamurthy A, De Marco García NV, Heck DH, Zhang J, Rajadhyaksha AM, Joyner AL. Cerebellar output neurons impair non-motor behaviors by altering development of extracerebellar connectivity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.08.602496. [PMID: 39026865 PMCID: PMC11257463 DOI: 10.1101/2024.07.08.602496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
The capacity of the brain to compensate for insults during development depends on the type of cell loss, whereas the consequences of genetic mutations in the same neurons are difficult to predict. We reveal powerful compensation from outside the cerebellum when the excitatory cerebellar output neurons are ablated embryonically and demonstrate that the minimum requirement for these neurons is for motor coordination and not learning and social behaviors. In contrast, loss of the homeobox transcription factors Engrailed1/2 (EN1/2) in the cerebellar excitatory lineage leads to additional deficits in adult learning and spatial working memory, despite half of the excitatory output neurons being intact. Diffusion MRI indicates increased thalamo-cortico-striatal connectivity in En1/2 mutants, showing that the remaining excitatory neurons lacking En1/2 exert adverse effects on extracerebellar circuits regulating motor learning and select non-motor behaviors. Thus, an absence of cerebellar output neurons is less disruptive than having cerebellar genetic mutations.
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Affiliation(s)
- Andrew S. Lee
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
| | - Tanzil M. Arefin
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York 10016, NY, USA
- Present Address: Center for Neurotechnology in Mental Health Research, Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16801, USA
| | - Alina Gubanova
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
| | - Daniel N. Stephen
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
| | - Yu Liu
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
- Center for Cerebellar Network Structure and Function in Health and Disease, University of Minnesota, Duluth, MN 55812, USA
| | - Zhimin Lao
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
| | - Anjana Krishnamurthy
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
| | - Natalia V. De Marco García
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York 10021, NY 10021, USA
| | - Detlef H. Heck
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
- Center for Cerebellar Network Structure and Function in Health and Disease, University of Minnesota, Duluth, MN 55812, USA
| | - Jiangyang Zhang
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York 10016, NY, USA
| | - Anjali M. Rajadhyaksha
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
- Pediatric Neurology, Department of Pediatrics, Weill Cornell Medicine, New York 10021, NY, USA
- Weill Cornell Autism Research Program, Weill Cornell Medicine, New York 10021, NY, USA
- Present address: Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA and Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Alexandra L. Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
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Tan T, Jiang L, He Z, Ding X, Xiong X, Tang M, Chen Y, Tang Y. NR1 Splicing Variant NR1a in Cerebellar Granule Neurons Constitutes a Better Motor Learning in the Mouse. CEREBELLUM (LONDON, ENGLAND) 2024; 23:1112-1120. [PMID: 37880519 PMCID: PMC11102416 DOI: 10.1007/s12311-023-01614-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/03/2023] [Indexed: 10/27/2023]
Abstract
As an excitatory neuron in the cerebellum, the granule cells play a crucial role in motor learning. The assembly of NMDAR in these neurons varies in developmental stages, while the significance of this variety is still not clear. In this study, we found that motor training could specially upregulate the expression level of NR1a, a splicing form of NR1 subunit. Interestingly, overexpression of this splicing variant in a cerebellar granule cell-specific manner dramatically elevated the NMDAR binding activity. Furthermore, the NR1a transgenic mice did not only show an enhanced motor learning, but also exhibit a higher efficacy for motor training in motor learning. Our results suggested that as a "junior" receptor, NR1a facilitates NMDAR activity as well as motor skill learning.
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Affiliation(s)
- Ting Tan
- Neurobiology Research Center, School of Medicine, Shenzhen Campus of Sun Yat-Sen University, Shenzhen, 518107, China
- Guangzhou Women and Children's Medical Center, Guangzhou Institute of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China
| | - Linyan Jiang
- Guangzhou Women and Children's Medical Center, Guangzhou Institute of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China
| | - Zhengxiao He
- Guangzhou Women and Children's Medical Center, Guangzhou Institute of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China
| | - Xuejiao Ding
- Guangzhou Women and Children's Medical Center, Guangzhou Institute of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China
| | - Xiaoli Xiong
- Guangzhou Women and Children's Medical Center, Guangzhou Institute of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China
| | - Mingxi Tang
- Department of Pathology, Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan, China.
| | - Yuan Chen
- Neurobiology Research Center, School of Medicine, Shenzhen Campus of Sun Yat-Sen University, Shenzhen, 518107, China.
| | - Yaping Tang
- Guangzhou Women and Children's Medical Center, Guangzhou Institute of Pediatrics, Guangzhou Medical University, Guangzhou, 510623, China.
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4
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Hu J, Wang Z, Gong B, Feng L, Song Y, Zhang S, Wang L, Qu Y, Li G, Zhang L, Zheng C, Du F, Li P, Wang Y. IFN-γ promotes radioresistant Nestin-expressing progenitor regeneration in the developing cerebellum by augmenting Shh ligand production. CNS Neurosci Ther 2024; 30:e14485. [PMID: 37789668 PMCID: PMC10805445 DOI: 10.1111/cns.14485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 09/05/2023] [Accepted: 09/18/2023] [Indexed: 10/05/2023] Open
Abstract
BACKGROUND Patients with brain tumors, especially pediatric brain tumors such as cerebellar medulloblastoma, always suffer from the severe side effects of radiotherapy. Regeneration of neural cells in irradiation-induced cerebellar injury has been reported, but the underlying mechanism remains elusive. METHODS We established an irradiation-induced developing cerebellum injury model in neonatal mice. Microarray, KEGG analysis and semi in vivo slice culture were performed for mechanistic study. RESULTS Nestin-expressing progenitors (NEPs) but not granule neuron precursors (GNPs) were resistant to irradiation and able to regenerate after irradiation. NEPs underwent less apoptosis but similar DNA damage following irradiation compared with GNPs. Subsequently, they started to proliferate and contributed to granule neurons regeneration dependent on the sonic hedgehog (Shh) pathway. In addition, irradiation increased Shh ligand provided by Purkinje cells. And microglia accumulated in the irradiated cerebellum producing more IFN-γ, which augmented Shh ligand production to promote NEP proliferation. CONCLUSIONS NEP was radioresistant and regenerative. IFN-γ was increased post irradiation to upregulate Shh ligand, contributing to NEP regeneration. Our study provides insight into the mechanisms of neural cell regeneration in irradiation injury of the developing cerebellum and will help to develop new therapeutic targets for minimizing the side effects of radiotherapy for brain tumors.
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Affiliation(s)
- Jian Hu
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Zixuan Wang
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Biao Gong
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Liyuan Feng
- Department of Pharmacognosy and Traditional Chinese Pharmacology, College of PharmacyArmy Medical UniversityChongqingChina
| | - Yan Song
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Shuo Zhang
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Lin Wang
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Yanghui Qu
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Gen Li
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Li Zhang
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Chaonan Zheng
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Fang Du
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
| | - Peng Li
- Department of Pharmacognosy and Traditional Chinese Pharmacology, College of PharmacyArmy Medical UniversityChongqingChina
| | - Yuan Wang
- Pediatric Cancer Center, Jiangsu Key Laboratory of Neuropsychiatric Diseases, Department of Pharmacology, College of Pharmaceutical SciencesSoochow UniversitySuzhouChina
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Schilling K. Revisiting the development of cerebellar inhibitory interneurons in the light of single-cell genetic analyses. Histochem Cell Biol 2024; 161:5-27. [PMID: 37940705 PMCID: PMC10794478 DOI: 10.1007/s00418-023-02251-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2023] [Indexed: 11/10/2023]
Abstract
The present review aims to provide a short update of our understanding of the inhibitory interneurons of the cerebellum. While these cells constitute but a minority of all cerebellar neurons, their functional significance is increasingly being recognized. For one, inhibitory interneurons of the cerebellar cortex are now known to constitute a clearly more diverse group than their traditional grouping as stellate, basket, and Golgi cells suggests, and this diversity is now substantiated by single-cell genetic data. The past decade or so has also provided important information about interneurons in cerebellar nuclei. Significantly, developmental studies have revealed that the specification and formation of cerebellar inhibitory interneurons fundamentally differ from, say, the cortical interneurons, and define a mode of diversification critically dependent on spatiotemporally patterned external signals. Last, but not least, in the past years, dysfunction of cerebellar inhibitory interneurons could also be linked with clinically defined deficits. I hope that this review, however fragmentary, may stimulate interest and help focus research towards understanding the cerebellum.
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Affiliation(s)
- Karl Schilling
- Anatomisches Institut - Anatomie und Zellbiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 10, 53115, Bonn, Germany.
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6
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Butler DF, Skibo J, Traudt CM, Millen KJ. Neonatal subarachnoid hemorrhage disrupts multiple aspects of cerebellar development. Front Mol Neurosci 2023; 16:1161086. [PMID: 37187957 PMCID: PMC10175619 DOI: 10.3389/fnmol.2023.1161086] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 04/10/2023] [Indexed: 05/17/2023] Open
Abstract
Over the past decade, survival rates for extremely low gestational age neonates (ELGANs; <28 weeks gestation) has markedly improved. Unfortunately, a significant proportion of ELGANs will suffer from neurodevelopmental dysfunction. Cerebellar hemorrhagic injury (CHI) has been increasingly recognized in the ELGANs population and may contribute to neurologic dysfunction; however, the underlying mechanisms are poorly understood. To address this gap in knowledge, we developed a novel model of early isolated posterior fossa subarachnoid hemorrhage (SAH) in neonatal mice and investigated both acute and long-term effects. Following SAH on postnatal day 6 (P6), we found significant decreased levels of proliferation with the external granular layer (EGL), thinning of the EGL, decreased Purkinje cell (PC) density, and increased Bergmann glial (BG) fiber crossings at P8. At P42, CHI resulted in decreased PC density, decreased molecular layer interneuron (MLI) density, and increased BG fiber crossings. Results from both Rotarod and inverted screen assays did not demonstrate significant effects on motor strength or learning at P35-38. Treatment with the anti-inflammatory drug Ketoprofen did not significantly alter our findings after CHI, suggesting that treatment of neuro-inflammation does not provide significant neuroprotection post CHI. Further studies are required to fully elucidate the mechanisms through which CHI disrupts cerebellar developmental programming in order to develop therapeutic strategies for neuroprotection in ELGANs.
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Affiliation(s)
- David F. Butler
- Division of Pediatric Critical Care, Seattle Children's Hospital, University of Washington, Seattle, WA, United States
| | - Jonathan Skibo
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | | | - Kathleen J. Millen
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
- Department of Pediatrics, University of Washington Medical School, Seattle, WA, United States
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7
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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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8
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Butler DF, Skibo J, Traudt CM, Millen KJ. Neonatal Subarachnoid Hemorrhage Disrupts Multiple Aspects of Cerebellar Development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.10.528048. [PMID: 36798230 PMCID: PMC9934646 DOI: 10.1101/2023.02.10.528048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Over the past decade, survival rates for extremely low gestational age neonates (ELGANs; <28 weeks gestation) has markedly improved. Unfortunately, a significant proportion of ELGANs will suffer from neurodevelopmental dysfunction. Cerebellar hemorrhagic injury (CHI) has been increasingly recognized in the ELGANs population and may contribute to neurologic dysfunction; however, the underlying mechanisms are poorly understood. To address this gap in knowledge, we developed a novel model of early isolated posterior fossa subarachnoid hemorrhage (SAH) in neonatal mice and investigated both acute and long-term effects. Following SAH on postnatal day 6 (P6), we found significant decreased levels of proliferation with the external granular layer (EGL), thinning of the EGL, decreased Purkinje cell (PC) density, and increased Bergmann glial (BG) fiber crossings at P8. At P42, CHI resulted in decreased PC density, decreased molecular layer interneuron (MLI) density, and increased BG fiber crossings. Results from both Rotarod and inverted screen assays did not demonstrate significant effects on motor strength or learning at P35-38. Treatment with the anti-inflammatory drug Ketoprofen did not significantly alter our findings after CHI, suggesting that treatment of neuro-inflammation does not provide significant neuroprotection post CHI. Further studies are required to fully elucidate the mechanisms through which CHI disrupts cerebellar developmental programming in order to develop therapeutic strategies for neuroprotection in ELGANs.
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9
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The Cerebellum in Niemann-Pick C1 Disease: Mouse Versus Man. CEREBELLUM (LONDON, ENGLAND) 2023; 22:102-119. [PMID: 35040097 DOI: 10.1007/s12311-021-01347-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/17/2021] [Indexed: 02/01/2023]
Abstract
Selective neuronal vulnerability is common to most degenerative disorders, including Niemann-Pick C (NPC), a rare genetic disease with altered intracellular trafficking of cholesterol. Purkinje cell dysfunction and loss are responsible for cerebellar ataxia, which is among the prevailing neurological signs of the NPC disease. In this review, we focus on some questions that are still unresolved. First, we frame the cerebellar vulnerability in the context of the extended postnatal time length by which the development of this structure is completed in mammals. In line with this thought, the much later development of cerebellar symptoms in humans is due to the later development and/or maturation of the cerebellum. Hence, the occurrence of developmental events under a protracted condition of defective intracellular cholesterol mobilization hits the functional maturation of the various cell types generating the ground of increased vulnerability. This is particularly consistent with the high cholesterol demand required for cell proliferation, migration, differentiation, and synapse formation/remodeling. Other major questions we address are why the progression of Purkinje cells loss is always from the anterior to the posterior lobes and why cerebellar defects persist in the mouse model even when genetic manipulations can lead to nearly normal survival.
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10
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Iskusnykh IY, Chizhikov VV. Cerebellar development after preterm birth. Front Cell Dev Biol 2022; 10:1068288. [PMID: 36523506 PMCID: PMC9744950 DOI: 10.3389/fcell.2022.1068288] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/09/2022] [Indexed: 11/30/2022] Open
Abstract
Preterm birth and its complications and the associated adverse factors, including brain hemorrhage, inflammation, and the side effects of medical treatments, are the leading causes of neurodevelopmental disability. Growing evidence suggests that preterm birth affects the cerebellum, which is the brain region involved in motor coordination, cognition, learning, memory, and social communication. The cerebellum is particularly vulnerable to the adverse effects of preterm birth because key cerebellar developmental processes, including the proliferation of neural progenitors, and differentiation and migration of neurons, occur in the third trimester of a human pregnancy. This review discusses the negative impacts of preterm birth and its associated factors on cerebellar development, focusing on the cellular and molecular mechanisms that mediate cerebellar pathology. A better understanding of the cerebellar developmental mechanisms affected by preterm birth is necessary for developing novel treatment and neuroprotective strategies to ameliorate the cognitive, behavioral, and motor deficits experienced by preterm subjects.
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11
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Joyner AL, Bayin NS. Cerebellum lineage allocation, morphogenesis and repair: impact of interplay amongst cells. Development 2022; 149:dev185587. [PMID: 36172987 PMCID: PMC9641654 DOI: 10.1242/dev.185587] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The cerebellum has a simple cytoarchitecture consisting of a folded cortex with three cell layers that surrounds a nuclear structure housing the output neurons. The excitatory neurons are generated from a unique progenitor zone, the rhombic lip, whereas the inhibitory neurons and astrocytes are generated from the ventricular zone. The growth phase of the cerebellum is driven by lineage-restricted progenitor populations derived from each zone. Research during the past decade has uncovered the importance of cell-to-cell communication between the lineages through largely unknown signaling mechanisms for regulating the scaling of cell numbers and cell plasticity during mouse development and following injury in the neonatal (P0-P14) cerebellum. This Review focuses on how the interplay between cell types is key to morphogenesis, production of robust neural circuits and replenishment of cells after injury, and ends with a discussion of the implications of the greater complexity of the human cerebellar progenitor zones for development and disease.
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Affiliation(s)
- Alexandra L. Joyner
- Developmental Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Biochemistry Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, Cornell University, New York, NY 10065, USA
| | - N. Sumru Bayin
- Wellcome Trust/Cancer Research UK Gurdon Institute, Cambridge University, Cambridge CB2 1NQ, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, CB2 3DY, UK
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12
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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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13
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Dendritic Inhibition by Shh Signaling-Dependent Stellate Cell Pool Is Critical for Motor Learning. J Neurosci 2022; 42:5130-5143. [PMID: 35589396 PMCID: PMC9236294 DOI: 10.1523/jneurosci.2073-21.2022] [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: 10/15/2021] [Revised: 03/14/2022] [Accepted: 04/11/2022] [Indexed: 12/31/2022] Open
Abstract
Cerebellar inhibitory interneurons are important regulators of neural circuit activity for diverse motor and nonmotor functions. The molecular layer interneurons (MLIs), consisting of basket cells (BCs) and stellate cells (SCs), provide dendritic and somatic inhibitory synapses onto Purkinje cells, respectively. They are sequentially generated in an inside-out pattern from Pax2+ immature interneurons, which migrate from the prospective white matter to the ML of the cortex. However, little is known about how MLI subtype identities and pool sizes are determined, nor are their contributions to motor learning well understood. Here, we show that GABAergic progenitors fated to generate both BCs and SCs respond to the Sonic hedgehog (Shh) signal. Conditional abrogation of Shh signaling of either sex inhibited proliferation of GABAergic progenitors and reduced the number of Pax2+ cells, whereas persistent Shh pathway activation increased their numbers. These changes, however, did not affect early born BC numbers but selectively altered the SC pool size. Moreover, genetic depletion of GABAergic progenitors when BCs are actively generated also resulted in a specific reduction of SCs, suggesting that the specification of MLI subtypes is independent of Shh signaling and their birth order and likely occurs after Pax2+ cells settle into their laminar positions in an inside-out sequence. Mutant mice with reduced SC numbers displayed decreased dendritic inhibitory synapses and neurotransmission onto Purkinje cells, resulting in an impaired acquisition of eyeblink conditioning. These findings also reveal an essential role of Shh signaling-dependent SCs in regulating inhibitory dendritic synapses and motor learning.SIGNIFICANCE STATEMENT The cerebellar circuit that enables fine motor learning involves MLIs of BCs and SCs, which provide dendritic and somatic inhibitory synapses onto Purkinje cells. Little is known about how their identities and numbers are determined, nor are their specific contributions to motor learning well understood. We show that MLI subtypes are specified independent of Shh signaling and their birth orders but appear to occur in their terminal laminar positions according to the inside-out sequence. This finding challenges the current view that MLI subtypes are specified sequentially at the progenitor level. We also demonstrate that dendritic inhibition by Shh signaling-dependent SC pool is necessary for motor learning.
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14
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Wang W, Shiraishi R, Kawauchi D. Sonic Hedgehog Signaling in Cerebellar Development and Cancer. Front Cell Dev Biol 2022; 10:864035. [PMID: 35573667 PMCID: PMC9100414 DOI: 10.3389/fcell.2022.864035] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/28/2022] [Indexed: 12/30/2022] Open
Abstract
The sonic hedgehog (SHH) pathway regulates the development of the central nervous system in vertebrates. Aberrant regulation of SHH signaling pathways often causes neurodevelopmental diseases and brain tumors. In the cerebellum, SHH secreted by Purkinje cells is a potent mitogen for granule cell progenitors, which are the most abundant cell type in the mature brain. While a reduction in SHH signaling induces cerebellar structural abnormalities, such as hypoplasia in various genetic disorders, the constitutive activation of SHH signaling often induces medulloblastoma (MB), one of the most common pediatric malignant brain tumors. Based on the existing literature on canonical and non-canonical SHH signaling pathways, emerging basic and clinical studies are exploring novel therapeutic approaches for MB by targeting SHH signaling at distinct molecular levels. In this review, we discuss the present consensus on SHH signaling mechanisms, their roles in cerebellar development and tumorigenesis, and the recent advances in clinical trials for MB.
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Affiliation(s)
- Wanchen Wang
- Department of Biochemistry and Cellular Biology, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan
| | - 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
- *Correspondence: Daisuke Kawauchi,
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15
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Combining low-density cell culture, single-cell tracking, and patch-clamp to monitor the behavior of postnatal murine cerebellar neural stem cells. STAR Protoc 2021; 2:100964. [PMID: 34841278 PMCID: PMC8605430 DOI: 10.1016/j.xpro.2021.100964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Low-density cell culture of the postnatal cerebellum, combined with live imaging and single-cell tracking, allows the behavior of postnatal cerebellar neural stem cells (NSCs) and their progeny to be monitored. Cultured cerebellar NSCs maintain their neurogenic nature giving rise, in the same relative proportions that exist in vivo, to the neuronal progeny generated by the three postnatal cerebellar neurogenic niches. This protocol describes the identification of the nature of the progeny through both post-imaging immunocytochemistry and patch-clamp recordings. For complete details on the use and execution of this protocol, please refer to Paniagua-Herranz et al. (2020b). Protocol to culture postnatal mouse cerebellar neural stem cells (NSCs) in low density The behavior of isolated postnatal cerebellar NSC can be monitored at single-cell level Protocol for simultaneous monitoring of the three postnatal cerebellar neurogenic niches Procedures of live imaging and single cell tracking for lineage tracing
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16
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Bayin NS, Mizrak D, Stephen DN, Lao Z, Sims PA, Joyner AL. Injury-induced ASCL1 expression orchestrates a transitory cell state required for repair of the neonatal cerebellum. SCIENCE ADVANCES 2021; 7:eabj1598. [PMID: 34878841 PMCID: PMC8654303 DOI: 10.1126/sciadv.abj1598] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 10/20/2021] [Indexed: 05/23/2023]
Abstract
To understand repair processes, it is critical to identify the molecular foundations underlying progenitor diversity and plasticity. Upon injury to the neonatal cerebellum, a normally gliogenic nestin-expressing progenitor (NEP) in the Bergmann glia layer (BgL) undergoes adaptive reprograming to restore granule cell production. However, the cellular states and genes regulating the NEP fate switch are unknown. Using single-cell RNA sequencing and fate mapping, we defined molecular subtypes of NEPs and their lineages under homeostasis and repair. NEPs contain two major subtypes: Hopx+ astrogliogenic and Ascl1+ neurogenic NEPs that are further subdivided based on their location, lineage, and differentiation status. Upon injury, an Ascl1+ transitory cellular state arises from Hopx+ BgL-NEPs. Furthermore, mutational analysis revealed that induction of Ascl1 is required for adaptive reprogramming by orchestrating a glial-to-neural switch in vivo following injury. Thus, we provide molecular and cellular insights into context-dependent progenitor plasticity and repair mechanisms in the brain.
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Affiliation(s)
- N. Sumru Bayin
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA
| | - Dogukan Mizrak
- Department of Systems Biology, Columbia University, New York, NY, USA
| | - Daniel N. Stephen
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA
| | - Zhimin Lao
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA
| | - Peter A. Sims
- Department of Systems Biology, Columbia University, New York, NY, USA
- Department of Biochemistry and Biophysics, Columbia University, New York, NY, USA
| | - Alexandra L. Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, USA
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
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17
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Yu J, She Y, Yang L, Zhuang M, Han P, Liu J, Lin X, Wang N, Chen M, Jiang C, Zhang Y, Yuan Y, Ji S. The m 6 A Readers YTHDF1 and YTHDF2 Synergistically Control Cerebellar Parallel Fiber Growth by Regulating Local Translation of the Key Wnt5a Signaling Components in Axons. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2101329. [PMID: 34643063 PMCID: PMC8596126 DOI: 10.1002/advs.202101329] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 08/26/2021] [Indexed: 05/23/2023]
Abstract
Messenger RNA m6 A modification is shown to regulate local translation in axons. However, how the m6 A codes in axonal mRNAs are read and decoded by the m6 A reader proteins is still unknown. Here, it is found that the m6 A readers YTHDF1 and YTHDF2 are both expressed in cerebellar granule cells (GCs) and their axons. Knockdown (KD) of YTHDF1 or YTHDF2 significantly increases GC axon growth rates in vitro. By integrating anti-YTHDF1&2 RIP-Seq with the quantitative proteomic analysis or RNA-seq after KD of YTHDF1 or YTHDF2, a group of transcripts which may mediate the regulation of GC axon growth by YTHDFs is identified. Among them, Dvl1 and Wnt5a, encoding the key components of Wnt pathway, are further found to be locally translated in axons, which are controlled by YTHDF1 and YTHDF2, respectively. Specific ablation of Ythdf1 or Ythdf2 in GCs increases parallel fiber growth, promotes synapse formation in cerebellum in vivo, and improves motor coordination ability. Together, this study identifies a mechanism by which the m6 A readers YTHDF1 and YTHDF2 work synergistically on the Wnt5a pathway through regulating local translation in GC axons to control cerebellar parallel fiber development.
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Affiliation(s)
- Jun Yu
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
- SUSTech‐HKU Joint PhD ProgramSchool of Biomedical SciencesLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina
| | - Yuanchu She
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Lixin Yang
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Mengru Zhuang
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Peng Han
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Jianhui Liu
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Xiaoyan Lin
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Nijia Wang
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Mengxian Chen
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Chunxuan Jiang
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Yujia Zhang
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Yujing Yuan
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
| | - Sheng‐Jian Ji
- School of Life SciencesDepartment of BiologyShenzhen Key Laboratory of Gene Regulation and Systems BiologyBrain Research CenterSouthern University of Science and TechnologyShenzhenGuangdong518055China
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18
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Luck R, Karakatsani A, Shah B, Schermann G, Adler H, Kupke J, Tisch N, Jeong HW, Back MK, Hetsch F, D'Errico A, De Palma M, Wiedtke E, Grimm D, Acker-Palmer A, von Engelhardt J, Adams RH, Augustin HG, Ruiz de Almodóvar C. The angiopoietin-Tie2 pathway regulates Purkinje cell dendritic morphogenesis in a cell-autonomous manner. Cell Rep 2021; 36:109522. [PMID: 34407407 PMCID: PMC9110807 DOI: 10.1016/j.celrep.2021.109522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 04/06/2021] [Accepted: 07/22/2021] [Indexed: 01/01/2023] Open
Abstract
Neuro-vascular communication is essential to synchronize central nervous system development. Here, we identify angiopoietin/Tie2 as a neuro-vascular signaling axis involved in regulating dendritic morphogenesis of Purkinje cells (PCs). We show that in the developing cerebellum Tie2 expression is not restricted to blood vessels, but it is also present in PCs. Its ligands angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2) are expressed in neural cells and endothelial cells (ECs), respectively. PC-specific deletion of Tie2 results in reduced dendritic arborization, which is recapitulated in neural-specific Ang1-knockout and Ang2 full-knockout mice. Mechanistically, RNA sequencing reveals that Tie2-deficient PCs present alterations in gene expression of multiple genes involved in cytoskeleton organization, dendritic formation, growth, and branching. Functionally, mice with deletion of Tie2 in PCs present alterations in PC network functionality. Altogether, our data propose Ang/Tie2 signaling as a mediator of intercellular communication between neural cells, ECs, and PCs, required for proper PC dendritic morphogenesis and function.
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Affiliation(s)
- Robert Luck
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Andromachi Karakatsani
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Bhavin Shah
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Geza Schermann
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Heike Adler
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Janina Kupke
- Department of Neurobiology, Interdisciplinary Centre for Neurosciences (IZN), University of Heidelberg, 69120 Heidelberg, Germany
| | - Nathalie Tisch
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
| | - Hyun-Woo Jeong
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, and University of Münster, Faculty of Medicine, 48149 Münster, Germany
| | - Michaela Kerstin Back
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Florian Hetsch
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Anna D'Errico
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, 60323 Frankfurt, Germany
| | - Michele De Palma
- Swiss Institute for Experimental Cancer Research (ISREC), Swiss Federal Institute of Technology in Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Ellen Wiedtke
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Bioquant Center, 69120 Heidelberg, Germany
| | - Dirk Grimm
- Department of Infectious Diseases/Virology, Medical Faculty, University of Heidelberg, Bioquant Center, 69120 Heidelberg, Germany; German Center for Infection Research (DZIF), and German Center for Cardiovascular Research (DZHK), Heidelberg, Germany
| | - Amparo Acker-Palmer
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences (BMLS), University of Frankfurt, 60323 Frankfurt, Germany
| | - Jakob von Engelhardt
- Institute of Pathophysiology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
| | - Ralf H Adams
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, and University of Münster, Faculty of Medicine, 48149 Münster, Germany
| | - Hellmut G Augustin
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany; Division of Vascular Oncology and Metastasis, German Cancer Research Center Heidelberg (DKFZ-ZMBH Alliance), 69120 Heidelberg, Germany
| | - Carmen Ruiz de Almodóvar
- European Center of Angioscience (ECAS), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany.
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19
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Choi JM, Acharya R, Marasini S, Narayan B, Lee KW, Hwang WS, Chang DY, Kim SS, Suh-Kim H. Cell Type-specific Knockout with Gli1-mediated Cre Recombination in the Developing Cerebellum. Exp Neurobiol 2021; 30:203-212. [PMID: 34230222 PMCID: PMC8278141 DOI: 10.5607/en21017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 12/02/2022] Open
Abstract
The inducible Cre-loxP system provides a useful tool for inducing the selective deletion of genes that are essential for proper development and enables the study of gene functions in properly developed animals. Here, we show that inducible Cre-loxP driven by the Gli1-promoter can induce cell-type-specific deletion of target genes in cerebellar cortical neurons. We used reporter mice containing the YFP (yellow fluorescence protein) gene at the Gt(ROSA)26Sor locus with a loxP-flanked transcriptional stop sequence, in which successful Cre-mediated excision of the stop sequence is indicated by YFP expression in Cre-expressing cells. Administration of tamoxifen during early postnatal days (P4~7) induces Cre-dependent excision of stop sequences and allows YFP expression in proliferating neuronal progenitor cells in the external granule layer and Bergmann glia in the Purkinje cell layer. A substantial number of YFP-positive progenitor cells in the external granule layer migrated to the internal granule cell layer and became granule cell neurons. By comparison, injection of tamoxifen during late postnatal days (P19~22) induces YFP expression only in Bergmann glia, and most granule cell neurons were devoid of YFP expression. The results indicate that the Gli1 promoter is temporarily active in progenitor cells in the external granule layer during the early postnatal period but constitutively active in Bergmann glia. We propose that the Gli1-mediated CreER system can be applied for the conditional deletion of genes of interest from cerebellar granule cell neurons and/or Bergmann glia.
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Affiliation(s)
- Jung-Mi Choi
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea
| | - Rakshya Acharya
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon 16499, Korea
| | | | - Bashyal Narayan
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon 16499, Korea
| | - Kwang-Wook Lee
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea
| | - Woo Sup Hwang
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea
| | | | - Sung-Soo Kim
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon 16499, Korea
| | - Haeyoung Suh-Kim
- Department of Anatomy, Ajou University School of Medicine, Suwon 16499, Korea.,Department of Biomedical Sciences, Graduate School, Ajou University School of Medicine, Suwon 16499, Korea.,Research Center, CelleBrain Ltd., Jeonju 54871, Korea
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20
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Zhang T, Liu T, Mora N, Guegan J, Bertrand M, Contreras X, Hansen AH, Streicher C, Anderle M, Danda N, Tiberi L, Hippenmeyer S, Hassan BA. Generation of excitatory and inhibitory neurons from common progenitors via Notch signaling in the cerebellum. Cell Rep 2021; 35:109208. [PMID: 34107249 DOI: 10.1016/j.celrep.2021.109208] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 03/29/2021] [Accepted: 05/11/2021] [Indexed: 12/17/2022] Open
Abstract
Brain neurons arise from relatively few progenitors generating an enormous diversity of neuronal types. Nonetheless, a cardinal feature of mammalian brain neurogenesis is thought to be that excitatory and inhibitory neurons derive from separate, spatially segregated progenitors. Whether bi-potential progenitors with an intrinsic capacity to generate both lineages exist and how such a fate decision may be regulated are unknown. Using cerebellar development as a model, we discover that individual progenitors can give rise to both inhibitory and excitatory lineages. Gradations of Notch activity determine the fates of the progenitors and their daughters. Daughters with the highest levels of Notch activity retain the progenitor fate, while intermediate levels of Notch activity generate inhibitory neurons, and daughters with very low levels of Notch signaling adopt the excitatory fate. Therefore, Notch-mediated binary cell fate choice is a mechanism for regulating the ratio of excitatory to inhibitory neurons from common progenitors.
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Affiliation(s)
- Tingting Zhang
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France; Doctoral School of Biomedical Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Tengyuan Liu
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France; Doctoral School of Biomedical Sciences, KU Leuven, 3000 Leuven, Belgium
| | - Natalia Mora
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France
| | - Justine Guegan
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France
| | - Mathilde Bertrand
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France
| | - Ximena Contreras
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Andi H Hansen
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Carmen Streicher
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Marica Anderle
- Armenise-Harvard Laboratory of Brain Disorders and Cancer, CIBIO, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Natasha Danda
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France
| | - Luca Tiberi
- Armenise-Harvard Laboratory of Brain Disorders and Cancer, CIBIO, University of Trento, Via Sommarive 9, 38123 Trento, Italy
| | - Simon Hippenmeyer
- Institute of Science and Technology Austria, Am Campus 1, 3400 Klosterneuburg, Austria
| | - Bassem A Hassan
- Institut du Cerveau (ICM), Sorbonne Université, INSERM, CNRS, Hôpital Pitié-Salpêtrière, Paris, France.
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21
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Kantzer CG, Parmigiani E, Cerrato V, Tomiuk S, Knauel M, Jungblut M, Buffo A, Bosio A. ACSA-2 and GLAST classify subpopulations of multipotent and glial-restricted cerebellar precursors. J Neurosci Res 2021; 99:2228-2249. [PMID: 34060113 PMCID: PMC8453861 DOI: 10.1002/jnr.24842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/12/2021] [Accepted: 03/17/2021] [Indexed: 12/13/2022]
Abstract
The formation of the cerebellum is highly coordinated to obtain its characteristic morphology and all cerebellar cell types. During mouse postnatal development, cerebellar progenitors with astroglial‐like characteristics generate mainly astrocytes and oligodendrocytes. However, a subset of astroglial‐like progenitors found in the prospective white matter (PWM) produces astroglia and interneurons. Characterizing these cerebellar astroglia‐like progenitors and distinguishing their developmental fates is still elusive. Here, we reveal that astrocyte cell surface antigen‐2 (ACSA‐2), lately identified as ATPase, Na+/K+ transporting, beta 2 polypeptide, is expressed by glial precursors throughout postnatal cerebellar development. In contrast to common astrocyte markers, ACSA‐2 appears on PWM cells but is absent on Bergmann glia (BG) precursors. In the adult cerebellum, ACSA‐2 is broadly expressed extending to velate astrocytes in the granular layer, white matter astrocytes, and to a lesser extent to BG. Cell transplantation and transcriptomic analysis revealed that marker staining discriminates two postnatal progenitor pools. One subset is defined by the co‐expression of ACSA‐2 and GLAST and the expression of markers typical of parenchymal astrocytes. These are PWM precursors that are exclusively gliogenic. They produce predominantly white matter and granular layer astrocytes. Another subset is constituted by GLAST positive/ACSA‐2 negative precursors that express neurogenic and BG‐like progenitor genes. This population displays multipotency and gives rise to interneurons besides all glial types, including BG. In conclusion, this work reports about ACSA‐2, a marker that in combination with GLAST enables for the discrimination and isolation of multipotent and glia‐committed progenitors, which generate different types of cerebellar astrocytes.
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Affiliation(s)
- Christina Geraldine Kantzer
- Miltenyi Biotec B.V. & Co. KG, Bergisch Gladbach, Germany.,Department of Cell and Molecular Biology, Karolinska Institute, Solna, Sweden
| | - Elena Parmigiani
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy.,Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy.,Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Valentina Cerrato
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy.,Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy.,Department of Fundamental Neurosciences, University of Lausanne, Lausanne, Switzerland
| | - Stefan Tomiuk
- Miltenyi Biotec B.V. & Co. KG, Bergisch Gladbach, Germany
| | - Michail Knauel
- Miltenyi Biotec B.V. & Co. KG, Bergisch Gladbach, Germany
| | | | - Annalisa Buffo
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy.,Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Italy
| | - Andreas Bosio
- Miltenyi Biotec B.V. & Co. KG, Bergisch Gladbach, Germany
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22
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Schinzel F, Seyfer H, Ebbers L, Nothwang HG. The Lbx1 lineage differentially contributes to inhibitory cell types of the dorsal cochlear nucleus, a cerebellum-like structure, and the cerebellum. J Comp Neurol 2021; 529:3032-3045. [PMID: 33786818 DOI: 10.1002/cne.25147] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 12/21/2022]
Abstract
The dorsal cochlear nucleus (DCN) is a mammalian-specific nucleus of the auditory system. Anatomically, it is classified as a cerebellum-like structure. These structures are proposed to share genetic programs with the cerebellum. Previous analyses demonstrated that inhibitory serial sister cell types (SCTs) of the DCN and cerebellum are derived from the pancreatic transcription factor 1a (Ptf1a) lineage. Postmitotic neurons of the Ptf1a lineage often express the transcription factor Ladybird homeobox protein homolog 1 (Lbx1) which is involved in neuronal cell fate determination. Lbx1 is therefore an attractive candidate for a further component of the genetic program shared between the DCN and cerebellum. Here, we used cell-type specific marker analysis in combination with an Lbx1 reporter mouse line to analyze in both tissues which cell types of the Ptf1a lineage express Lbx1. In the DCN, stellate cells and Purkinje-like cartwheel cells were part of the Lbx1 lineage and Golgi cells were not, as determined by cell counts. In contrast, in the cerebellum, stellate cells and Golgi cells were part of the Lbx1 lineage and Purkinje cells were not. Hence, two out of three phenotypically similar cell types differed with respect to their Lbx1 expression. Our study demonstrates that Lbx1 is differentially recruited to the developmental genetic program of inhibitory neurons both within a given tissue and between the DCN and cerebellum. The differential expression of Lbx1 within the DCN and the cerebellum might contribute to the genetic individuation of the inhibitory SCTs to adapt to circuit specific tasks.
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Affiliation(s)
- Friedrich Schinzel
- Division of Neurogenetics and Cluster of Excellence Hearing4All, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Hannah Seyfer
- Division of Neurogenetics and Cluster of Excellence Hearing4All, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Lena Ebbers
- Division of Neurogenetics and Cluster of Excellence Hearing4All, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Hans Gerd Nothwang
- Division of Neurogenetics and Cluster of Excellence Hearing4All, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany.,Research Center for Neurosensory Science, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
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23
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Developmental Maturation of the Cerebellar White Matter-an Instructive Environment for Cerebellar Inhibitory Interneurons. THE CEREBELLUM 2020; 19:286-308. [PMID: 32002802 PMCID: PMC7082410 DOI: 10.1007/s12311-020-01111-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In the developing cerebellum, the nascent white matter (WM) serves as an instructive niche for cerebellar cortical inhibitory interneurons. As their Pax2 expressing precursors transit the emerging WM, their laminar fate is programmed. The source(s) and nature of the signals involved remain unknown. Here, we used immunocytochemistry to follow the cellular maturation of the murine cerebellar WM during this critical period. During the first few days of postnatal development, when most Pax2 expressing cells are formed and many of them reach the cerebellar gray matter, only microglial cells can be identified in the territories through which Pax2 cells migrate. From p4 onward, cells expressing the oligodendrocytic or astrocyte markers, CNP-1, MBP or GFAP, started to appear in the nascent WM. Expression of macroglial markers increased with cerebellar differentiation, yet deep nuclei remained GFAP-negative at all ages. The progressive spread of maturing glia did not correlate with the exit of Pax2 cells from the WM, as indicated by the extensive mingling of these cells up to p15. Whereas sonic hedgehog-associated p75NTR expression could be verified in granule cell precursors, postmitotic Pax2 cells are p75NTR negative at all ages analyzed. Thus, if Pax2 cells, like their precursors, are sensitive to sonic hedgehog, this does not affect their expression of p75NTR. Our findings document that subsequently generated sets of Pax2 expressing precursors of inhibitory cerebellar interneurons are confronted with a dynamically changing complement of cerebellar glia. The eventual identification of fate-defining pathways should profit from the covariation with glial maturation predicted by the present findings.
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24
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Macrì S, Di-Poï N. Heterochronic Developmental Shifts Underlying Squamate Cerebellar Diversity Unveil the Key Features of Amniote Cerebellogenesis. Front Cell Dev Biol 2020; 8:593377. [PMID: 33195265 PMCID: PMC7642464 DOI: 10.3389/fcell.2020.593377] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 09/25/2020] [Indexed: 11/13/2022] Open
Abstract
Despite a remarkable conservation of architecture and function, the cerebellum of vertebrates shows extensive variation in morphology, size, and foliation pattern. These features make this brain subdivision a powerful model to investigate the evolutionary developmental mechanisms underlying neuroanatomical complexity both within and between anamniote and amniote species. Here, we fill a major evolutionary gap by characterizing the developing cerebellum in two non-avian reptile species-bearded dragon lizard and African house snake-representative of extreme cerebellar morphologies and neuronal arrangement patterns found in squamates. Our data suggest that developmental strategies regarded as exclusive hallmark of birds and mammals, including transit amplification in an external granule layer (EGL) and Sonic hedgehog expression by underlying Purkinje cells (PCs), contribute to squamate cerebellogenesis independently from foliation pattern. Furthermore, direct comparison of our models suggests the key importance of spatiotemporal patterning and dynamic interaction between granule cells and PCs in defining cortical organization. Especially, the observed heterochronic shifts in early cerebellogenesis events, including upper rhombic lip progenitor activity and EGL maintenance, are strongly expected to affect the dynamics of molecular interaction between neuronal cell types in snakes. Altogether, these findings help clarifying some of the morphogenetic and molecular underpinnings of amniote cerebellar corticogenesis, but also suggest new potential molecular mechanisms underlying cerebellar complexity in squamates. Furthermore, squamate models analyzed here are revealed as key animal models to further understand mechanisms of brain organization.
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Affiliation(s)
- Simone Macrì
- Program in Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Nicolas Di-Poï
- Program in Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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25
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Paniagua-Herranz L, Menéndez-Méndez A, Gómez-Villafuertes R, Olivos-Oré LA, Biscaia M, Gualix J, Pérez-Sen R, Delicado EG, Artalejo AR, Miras-Portugal MT, Ortega F. Live Imaging Reveals Cerebellar Neural Stem Cell Dynamics and the Role of VNUT in Lineage Progression. Stem Cell Reports 2020; 15:1080-1094. [PMID: 33065045 PMCID: PMC7663791 DOI: 10.1016/j.stemcr.2020.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 11/04/2022] Open
Abstract
Little is known about the intrinsic specification of postnatal cerebellar neural stem cells (NSCs) and to what extent they depend on information from their local niche. Here, we have used an adapted cell preparation of isolated postnatal NSCs and live imaging to demonstrate that cerebellar progenitors maintain their neurogenic nature by displaying hallmarks of NSCs. Furthermore, by using this preparation, all the cell types produced postnatally in the cerebellum, in similar relative proportions to those observed in vivo, can be monitored. The fact that neurogenesis occurs in such organized manner in the absence of signals from the local environment, suggests that cerebellar lineage progression is to an important extent governed by cell-intrinsic or pre-programmed events. Finally, we took advantage of the absence of the niche to assay the influence of the vesicular nucleotide transporter inhibition, which dramatically reduced the number of NSCs in vitro by promoting their progression toward neurogenesis. We present a preparation that allows monitoring the behavior of cerebellar NSCs Isolated NSCs maintain their neurogenic nature in absence of niche factors The model enables monitoring the three postnatal cerebellar niches simultaneously VNUT influences the balance between quiescence and activation of cerebellar NSCs
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Affiliation(s)
- Lucía Paniagua-Herranz
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Aida Menéndez-Méndez
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Rosa Gómez-Villafuertes
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Luis A Olivos-Oré
- Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain; Department of Pharmacology and Toxicology, Faculty of Veterinary, Universidad Complutense de Madrid, Madrid, Spain
| | - Miguel Biscaia
- Faculty of Biomedical and Health Sciences, Universidad Europea de Madrid, Madrid, Spain
| | - Javier Gualix
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Raquel Pérez-Sen
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Esmerilda G Delicado
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Antonio R Artalejo
- Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain; Department of Pharmacology and Toxicology, Faculty of Veterinary, Universidad Complutense de Madrid, Madrid, Spain
| | - María Teresa Miras-Portugal
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain
| | - Felipe Ortega
- Departament of Biochemistry and Molecular Biology, Faculty of Veterinary, Universidad Complutense de Madrid (UCM), Madrid, Spain; Instituto Universitario de Investigación en Neuroquímica (IUIN), Madrid, Spain; Instituto de Investigación Sanitaria San Carlos (IdISSC), Madrid, Spain.
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26
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Terry TT, Cheng T, Mahjoub M, Zong H. Mosaic Analysis with Double Markers reveals IGF1R function in granule cell progenitors during cerebellar development. Dev Biol 2020; 465:130-143. [PMID: 32697974 DOI: 10.1016/j.ydbio.2020.07.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 12/13/2022]
Abstract
During cerebellar development, granule cell progenitors (GCPs) proliferate exponentially for a fixed period, promoted by paracrine mitogenic factor Sonic Hedgehog (Shh) secreted from Purkinje cells (PCs). Dysregulation of Shh signaling leads to uncontrolled GCP proliferation and medulloblastoma. Serendipitously our previous work discovered insulin-like growth factor 1 (IGF1) as another key driver for medulloblastoma, which led to the current investigation into the role of IGF1 in GCPs during normal development. While the IGF1R conditional knockout model revealed GCP defects in anterior cerebellum, the posterior cerebellum was mostly intact, likely owing to incomplete excision of floxed alleles. To circumvent this hurdle, we enlisted a mouse genetic system called Mosaic Analysis of Double Markers (MADM), which sporadically generates homozygous null cells unequivocally labeled with GFP and their wildtype sibling cells labeled with RFP, enabling phenotypic analysis at single-cell resolution. Using MADM, we found that loss of IGF1R resulted in a 10-fold reduction of GCs in both anterior and posterior cerebellum; and that hindered S phase entry and increased cell cycle exit collectively led to this phenotype. Genetic interaction studies showed that IGF1 signaling prevents GCP cell cycle exit at least partially through suppressing the level of p27kip1, a negative regulator of cell cycle. Finally, we found that IGF1 is produced by PCs in a temporally regulated fashion: it is highly expressed early in development when GCPs proliferate exponentially, then gradually decline as GCPs commit to cell cycle exit. Taken together, our studies reveal IGF1 as a paracrine factor that positively regulates GCP cell cycle in cooperation with Shh, through dampening the level of p27 to prevent precocious cell cycle exit. Our work not only showcases the power of phenotypic analysis by the MADM system but also provides an excellent example of multi-factorial regulation of robust developmental programs.
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Affiliation(s)
- Tiffany T Terry
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA
| | - Tao Cheng
- Department of Medicine, Division of Nephrology, Washington University in St. Louis, St. Louis, MO, USA
| | - Moe Mahjoub
- Department of Medicine, Division of Nephrology, Washington University in St. Louis, St. Louis, MO, USA
| | - Hui Zong
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, USA.
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27
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Glial Factors Regulating White Matter Development and Pathologies of the Cerebellum. Neurochem Res 2020; 45:643-655. [PMID: 31974933 PMCID: PMC7058568 DOI: 10.1007/s11064-020-02961-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 01/07/2020] [Accepted: 01/09/2020] [Indexed: 12/31/2022]
Abstract
The cerebellum is a brain region that undergoes extremely dynamic growth during perinatal and postnatal development which is regulated by the proper interaction between glial cells and neurons with a complex concert of growth factors, chemokines, cytokines, neurotransmitters and transcriptions factors. The relevance of cerebellar functions for not only motor performance but also for cognition, emotion, memory and attention is increasingly being recognized and acknowledged. Since perturbed circuitry of cerebro-cerebellar trajectories can play a role in many central nervous system pathologies and thereby contribute to neurological symptoms in distinct neurodevelopmental and neurodegenerative diseases, is it the aim with this mini-review to highlight the pathways of glia–glia interplay being involved. The designs of future treatment strategies may hence be targeted to molecular pathways also playing a role in development and disease of the cerebellum.
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28
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Willett RT, Bayin NS, Lee AS, Krishnamurthy A, Wojcinski A, Lao Z, Stephen D, Rosello-Diez A, Dauber-Decker KL, Orvis GD, Wu Z, Tessier-Lavigne M, Joyner AL. Cerebellar nuclei excitatory neurons regulate developmental scaling of presynaptic Purkinje cell number and organ growth. eLife 2019; 8:e50617. [PMID: 31742552 PMCID: PMC6890462 DOI: 10.7554/elife.50617] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 11/18/2019] [Indexed: 01/17/2023] Open
Abstract
For neural systems to function effectively, the numbers of each cell type must be proportioned properly during development. We found that conditional knockout of the mouse homeobox genes En1 and En2 in the excitatory cerebellar nuclei neurons (eCN) leads to reduced postnatal growth of the cerebellar cortex. A subset of medial and intermediate eCN are lost in the mutants, with an associated cell non-autonomous loss of their presynaptic partner Purkinje cells by birth leading to proportional scaling down of neuron production in the postnatal cerebellar cortex. Genetic killing of embryonic eCN throughout the cerebellum also leads to loss of Purkinje cells and reduced postnatal growth but throughout the cerebellar cortex. Thus, the eCN play a key role in scaling the size of the cerebellum by influencing the survival of their Purkinje cell partners, which in turn regulate production of granule cells and interneurons via the amount of sonic hedgehog secreted.
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Affiliation(s)
- Ryan T Willett
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
| | - N Sumru Bayin
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
| | - Andrew S Lee
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
- Neuroscience ProgramWeill Cornell Graduate School of Medical SciencesNew YorkUnited States
| | - Anjana Krishnamurthy
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
- Neuroscience ProgramWeill Cornell Graduate School of Medical SciencesNew YorkUnited States
| | | | - Zhimin Lao
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
| | - Daniel Stephen
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
| | | | | | - Grant D Orvis
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
| | - Zhuhao Wu
- The Laboratory of Brain Development and RepairThe Rockefeller UniversityNew YorkUnited States
| | - Marc Tessier-Lavigne
- The Laboratory of Brain Development and RepairThe Rockefeller UniversityNew YorkUnited States
| | - Alexandra L Joyner
- Developmental Biology ProgramSloan Kettering InstituteNew YorkUnited States
- Neuroscience ProgramWeill Cornell Graduate School of Medical SciencesNew YorkUnited States
- Biochemistry, Cell and Molecular Biology ProgramWeill Cornell Graduate School of Medical SciencesNew YorkUnited States
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29
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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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30
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Vladoiu MC, El-Hamamy I, Donovan LK, Farooq H, Holgado BL, Sundaravadanam Y, Ramaswamy V, Hendrikse LD, Kumar S, Mack SC, Lee JJY, Fong V, Juraschka K, Przelicki D, Michealraj A, Skowron P, Luu B, Suzuki H, Morrissy AS, Cavalli FMG, Garzia L, Daniels C, Wu X, Qazi MA, Singh SK, Chan JA, Marra MA, Malkin D, Dirks P, Heisler L, Pugh T, Ng K, Notta F, Thompson EM, Kleinman CL, Joyner AL, Jabado N, Stein L, Taylor MD. Childhood cerebellar tumours mirror conserved fetal transcriptional programs. Nature 2019; 572:67-73. [PMID: 31043743 PMCID: PMC6675628 DOI: 10.1038/s41586-019-1158-7] [Citation(s) in RCA: 247] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 03/22/2019] [Indexed: 11/25/2022]
Abstract
Study of the origin and development of cerebellar tumours has been hampered by the complexity and heterogeneity of cerebellar cells that change over the course of development. Here we use single-cell transcriptomics to study more than 60,000 cells from the developing mouse cerebellum and show that different molecular subgroups of childhood cerebellar tumours mirror the transcription of cells from distinct, temporally restricted cerebellar lineages. The Sonic Hedgehog medulloblastoma subgroup transcriptionally mirrors the granule cell hierarchy as expected, while group 3 medulloblastoma resembles Nestin+ stem cells, group 4 medulloblastoma resembles unipolar brush cells, and PFA/PFB ependymoma and cerebellar pilocytic astrocytoma resemble the prenatal gliogenic progenitor cells. Furthermore, single-cell transcriptomics of human childhood cerebellar tumours demonstrates that many bulk tumours contain a mixed population of cells with divergent differentiation. Our data highlight cerebellar tumours as a disorder of early brain development and provide a proximate explanation for the peak incidence of cerebellar tumours in early childhood.
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Affiliation(s)
- Maria C Vladoiu
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Ibrahim El-Hamamy
- Computational Biology Program, Ontario Institute for Cancer Research, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Laura K Donovan
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Hamza Farooq
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Borja L Holgado
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yogi Sundaravadanam
- Computational Biology Program, Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Vijay Ramaswamy
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Division of Haematology/Oncology, Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Liam D Hendrikse
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Sachin Kumar
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Stephen C Mack
- Brain Tumor Program, Children's Cancer Center and Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - John J Y Lee
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Vernon Fong
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Kyle Juraschka
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - David Przelicki
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Antony Michealraj
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Patryk Skowron
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Betty Luu
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Hiromichi Suzuki
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - A Sorana Morrissy
- Department of Biochemistry & Molecular Biology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Florence M G Cavalli
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Livia Garzia
- Cancer Research Program, McGill University Health Centre Research Institute, Montreal, Quebec, Canada
| | - Craig Daniels
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Xiaochong Wu
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Maleeha A Qazi
- Stem Cell and Cancer Research Institute, McMaster University, Hamilton, Ontario, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Sheila K Singh
- Stem Cell and Cancer Research Institute, McMaster University, Hamilton, Ontario, Canada
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Department of Surgery, McMaster University, Hamilton, Ontario, Canada
| | - Jennifer A Chan
- Charbonneau Cancer Institute, University of Calgary, Calgary, Alberta, Canada
| | - Marco A Marra
- Canada's Michael Smith Genome Sciences Centre, BC Cancer Agency, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - David Malkin
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Peter Dirks
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
- Division of Neurosurgery, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Lawrence Heisler
- Computational Biology Program, Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Trevor Pugh
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
- Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Karen Ng
- Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Faiyaz Notta
- Ontario Institute for Cancer Research, Toronto, Ontario, Canada
| | - Eric M Thompson
- Department of Neurosurgery, Duke University Medical Center, Durham, NC, USA
| | - Claudia L Kleinman
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada
- Lady Davis Research Institute, Jewish General Hospital, Montreal, Quebec, Canada
| | - Alexandra L Joyner
- Developmental Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Nada Jabado
- Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada.
| | - Lincoln Stein
- Computational Biology Program, Ontario Institute for Cancer Research, Toronto, Ontario, Canada.
| | - Michael D Taylor
- Developmental & Stem Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada.
- The Arthur and Sonia Labatt Brain Tumor Research Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
- Division of Neurosurgery, The Hospital for Sick Children, Toronto, Ontario, Canada.
- Department of Surgery and Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
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31
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Yang Z, Joyner AL. YAP1 is involved in replenishment of granule cell precursors following injury to the neonatal cerebellum. Dev Biol 2019; 455:458-472. [PMID: 31376393 DOI: 10.1016/j.ydbio.2019.07.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/30/2019] [Accepted: 07/30/2019] [Indexed: 01/08/2023]
Abstract
The cerebellum undergoes major rapid growth during the third trimester and early neonatal stage in humans, making it vulnerable to injuries in pre-term babies. Experiments in mice have revealed a remarkable ability of the neonatal cerebellum to recover from injuries around birth. In particular, recovery following irradiation-induced ablation of granule cell precursors (GCPs) involves adaptive reprogramming of Nestin-expressing glial progenitors (NEPs). Sonic hedgehog signaling is required for the initial step in NEP reprogramming; however, the full spectrum of developmental signaling pathways that promote NEP-driven regeneration is not known. Since the growth regulatory Hippo pathway has been implicated in the repair of several tissue types, we tested whether Hippo signaling is involved in regeneration of the cerebellum. Using mouse models, we found that the Hippo pathway transcriptional co-activator YAP1 (Yes-associated protein 1) but not TAZ (transcriptional coactivator with PDZ binding motif, or WWTR1) is required in NEPs for full recovery of cerebellar growth following irradiation one day after birth. Although Yap1 plays only a minor role during normal development in differentiation of NEPs or GCPs, the size of the cerebellum, and in particular the internal granule cell layer produced by GCPs, is significantly reduced in Yap1 mutants after irradiation, and the organization of Purkinje cells and Bergmann glial fibers is disrupted. The initial proliferative response of Yap1 mutant NEPs to irradiation is normal and the cells migrate to the GCP niche, but subsequently there is increased cell death of GCPs and altered migration of granule cells, possibly due to defects in Bergmann glia. Moreover, loss of Taz along with Yap1 in NEPs does not abrogate regeneration or alter development of the cerebellum. Our study provides new insights into the molecular signaling underlying postnatal cerebellar development and regeneration.
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Affiliation(s)
- Zhaohui Yang
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY, 10065, United States; Developmental Biology Program, Sloan Kettering Institute, New York, NY, 10065, United States
| | - Alexandra L Joyner
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY, 10065, United States; Developmental Biology Program, Sloan Kettering Institute, New York, NY, 10065, United States.
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32
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Naughton M, McMahon J, Healy S, FitzGerald U. Profile of the unfolded protein response in rat cerebellar cortical development. J Comp Neurol 2019; 527:2910-2924. [PMID: 31132146 DOI: 10.1002/cne.24718] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 04/01/2019] [Accepted: 05/16/2019] [Indexed: 12/13/2022]
Abstract
The unfolded protein response (UPR) has been reported during normal development of cortical neurons and cerebellar white matter and may also contribute to the pathogenesis of neurological conditions, such as Marinesco-Sjogren syndrome and Borna virus infection, which result in cerebellar defects. The UPR is initiated when the processing capacity of the endoplasmic reticulum (ER) is overwhelmed. Misfolded proteins accumulate and can activate ER stress sensors; PKR-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1 (IRE1), activated transcription factor 6 (ATF6) and their downstream targets glucose-regulated protein 78 (GRP78), glucose-regulated protein 94 (GRP94) and protein disulfide isomerase (PDI). In order to provide a fuller appreciation of the possible importance of ER stress-associated proteins in the context of cerebellar disease, we have profiled the expression of ER stress sensors and their downstream targets in the developing cerebellar cortex in postnatal rat. Activation of PERK and IRE1 stress sensors was observed for the first time in normally developing granule cell precursors. A second proliferative pPERK-positive population was also detected in the internal granular layer (IGL). In general, the density of UPR protein-positive cells was found to decrease significantly when profiles in early and late postnatal ages were compared. These data may be relevant to studies of medulloblastoma and warrant further investigation.
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Affiliation(s)
- Michelle Naughton
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Jill McMahon
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Sinéad Healy
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Una FitzGerald
- Galway Neuroscience Centre, School of Natural Sciences, National University of Ireland, Galway, Ireland
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33
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Fiorenza MT, Moro E, Erickson RP. The pathogenesis of lysosomal storage disorders: beyond the engorgement of lysosomes to abnormal development and neuroinflammation. Hum Mol Genet 2019; 27:R119-R129. [PMID: 29718288 DOI: 10.1093/hmg/ddy155] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 04/24/2018] [Indexed: 01/03/2023] Open
Abstract
There is growing evidence that the complex clinical manifestations of lysosomal storage diseases (LSDs) are not fully explained by the engorgement of the endosomal-autophagic-lysosomal system. In this review, we explore current knowledge of common pathogenetic mechanisms responsible for the early onset of tissue abnormalities of two LSDs, Mucopolysaccharidosis type II (MPSII) and Niemann-Pick type C (NPC) diseases. In particular, perturbations of the homeostasis of glycosaminoglycans (GAGs) and cholesterol (Chol) in MPSII and NPC diseases, respectively, affect key biological processes, including morphogen signaling. Both GAGs and Chol finely regulate the release, reception and tissue distribution of Shh. Hence, not surprisingly, developmental processes depending on correct Shh signaling have been found altered in both diseases. Besides abnormal signaling, exaggerated activation of microglia and impairment of autophagy and mitophagy occur in both diseases, largely before the appearance of typical pathological signs.
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Affiliation(s)
- Maria Teresa Fiorenza
- Division of Neuroscience, Department of Psychology and "Daniel Bovet" Neurobiology Research Center, Sapienza University of Rome, Rome, Italy.,IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Enrico Moro
- Department of Molecular Medicine, University of Padova, Padova, Italy
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34
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Wojcinski A, Morabito M, Lawton AK, Stephen DN, Joyner AL. Genetic deletion of genes in the cerebellar rhombic lip lineage can stimulate compensation through adaptive reprogramming of ventricular zone-derived progenitors. Neural Dev 2019; 14:4. [PMID: 30764875 PMCID: PMC6375182 DOI: 10.1186/s13064-019-0128-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 01/17/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The cerebellum is a foliated posterior brain structure involved in coordination of motor movements and cognition. The cerebellum undergoes rapid growth postnataly due to Sonic Hedgehog (SHH) signaling-dependent proliferation of ATOH1+ granule cell precursors (GCPs) in the external granule cell layer (EGL), a key step for generating cerebellar foliation and the correct number of granule cells. Due to its late development, the cerebellum is particularly vulnerable to injury from preterm birth and stress around birth. We recently uncovered an intrinsic capacity of the developing cerebellum to replenish ablated GCPs via adaptive reprogramming of Nestin-expressing progenitors (NEPs). However, whether this compensation mechanism occurs in mouse mutants affecting the developing cerebellum and could lead to mis-interpretation of phenotypes was not known. METHODS We used two different approaches to remove the main SHH signaling activator GLI2 in GCPs: 1) Our mosaic mutant analysis with spatial and temporal control of recombination (MASTR) technique to delete Gli2 in a small subset of GCPs; 2) An Atoh1-Cre transgene to delete Gli2 in most of the EGL. Genetic Inducible Fate Mapping (GIFM) and live imaging were used to analyze the behavior of NEPs after Gli2 deletion. RESULTS Mosaic analysis demonstrated that SHH-GLI2 signaling is critical for generating the correct pool of granule cells by maintaining GCPs in an undifferentiated proliferative state and promoting their survival. Despite this, inactivation of GLI2 in a large proportion of GCPs in the embryo did not lead to the expected dramatic reduction in the size of the adult cerebellum. GIFM uncovered that NEPs do indeed replenish GCPs in Gli2 conditional mutants, and then expand and partially restore the production of granule cells. Furthermore, the SHH signaling-dependent NEP compensation requires Gli2, demonstrating that the activator side of the pathway is involved. CONCLUSION We demonstrate that a mouse conditional mutation that results in loss of SHH signaling in GCPs is not sufficient to induce long term severe cerebellum hypoplasia. The ability of the neonatal cerebellum to regenerate after loss of cells via a response by NEPs must therefore be considered when interpreting the phenotypes of Atoh1-Cre conditional mutants affecting GCPs.
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Affiliation(s)
- Alexandre Wojcinski
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, Box 511, New York, NY, 10065, USA
| | - Morgane Morabito
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, Box 511, New York, NY, 10065, USA
| | - Andrew K Lawton
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, Box 511, New York, NY, 10065, USA
| | - Daniel N Stephen
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, Box 511, New York, NY, 10065, USA
| | - Alexandra L Joyner
- Developmental Biology Program, Sloan Kettering Institute, 1275 York Avenue, Box 511, New York, NY, 10065, USA.
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, NY, 10065, USA.
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35
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Wizeman JW, Guo Q, Wilion EM, Li JYH. Specification of diverse cell types during early neurogenesis of the mouse cerebellum. eLife 2019; 8:e42388. [PMID: 30735127 PMCID: PMC6382353 DOI: 10.7554/elife.42388] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 02/07/2019] [Indexed: 12/22/2022] Open
Abstract
We applied single-cell RNA sequencing to profile genome-wide gene expression in about 9400 individual cerebellar cells from the mouse embryo at embryonic day 13.5. Reiterative clustering identified the major cerebellar cell types and subpopulations of different lineages. Through pseudotemporal ordering to reconstruct developmental trajectories, we identified novel transcriptional programs controlling cell fate specification of populations arising from the ventricular zone and the rhombic lip, two distinct germinal zones of the embryonic cerebellum. Together, our data revealed cell-specific markers for studying the cerebellum, gene-expression cascades underlying cell fate specification, and a number of previously unknown subpopulations that may play an integral role in the formation and function of the cerebellum. Our findings will facilitate new discovery by providing insights into the molecular and cell type diversity in the developing cerebellum.
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Affiliation(s)
- John W Wizeman
- Department of Genetics and Genome Sciences, School of MedicineUniversity of ConnecticutFarmingtonUnited States
| | - Qiuxia Guo
- Department of Genetics and Genome Sciences, School of MedicineUniversity of ConnecticutFarmingtonUnited States
| | | | - James YH Li
- Department of Genetics and Genome Sciences, School of MedicineUniversity of ConnecticutFarmingtonUnited States
- Institute for Systems GenomicsUniversity of ConnecticutFarmingtonUnited States
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36
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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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37
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Cerrato V, Parmigiani E, Figueres-Oñate M, Betizeau M, Aprato J, Nanavaty I, Berchialla P, Luzzati F, de’Sperati C, López-Mascaraque L, Buffo A. Multiple origins and modularity in the spatiotemporal emergence of cerebellar astrocyte heterogeneity. PLoS Biol 2018; 16:e2005513. [PMID: 30260948 PMCID: PMC6178385 DOI: 10.1371/journal.pbio.2005513] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Revised: 10/09/2018] [Accepted: 09/13/2018] [Indexed: 12/21/2022] Open
Abstract
The morphological, molecular, and functional heterogeneity of astrocytes is under intense scrutiny, but how this diversity is ontogenetically achieved remains largely unknown. Here, by quantitative in vivo clonal analyses and proliferation studies, we demonstrate that the major cerebellar astrocyte types emerge according to an unprecedented and remarkably orderly developmental program comprising (i) a time-dependent decline in both clone size and progenitor multipotency, associated with clone allocation first to the hemispheres and then to the vermis(ii) distinctive clonal relationships among astrocyte types, revealing diverse lineage potentials of embryonic and postnatal progenitors; and (iii) stereotyped clone architectures and recurrent modularities that correlate to layer-specific dynamics of postnatal proliferation/differentiation. In silico simulations indicate that the sole presence of a unique multipotent progenitor at the source of the whole astrogliogenic program is unlikely and rather suggest the involvement of additional committed components. Astrocytes are abundant cells of the brain essential to support and shape neuronal activity. They can be grouped in different subclasses based on their remarkable variety of morphologies, molecular profiles, and specialized functions. Although different astrocyte types likely display specialized interactions with distinct neuron categories, the different classes of astrocytes have only partially been unmasked. How astrocyte heterogeneity is ontogenetically achieved remains largely unknown. Here we approached this question by studying the development of the main astrocyte types of the cerebellum. The reconstruction of developmental lineages in the mouse embryo combined with proliferation studies and computational modeling demonstrate that cerebellar astrocyte types emerge according to an unprecedented and remarkably orderly developmental program. Embryonic progenitor cells produce either only a single astrocyte type or more types. These distinct astrocyte lineages display stereotyped architectures and recurrent modularities. Moreover, the generation of astrocytes follows a well-defined spatiotemporal pattern, defined by a time-dependent allocation of astrocytes to distinct cerebellar territories and an inside-out sequence of differentiation, coupled with a decline over time in both progenitor amplification and capability to produce distinct astrocyte types. These results provide the first evidence that an ontogenetic program, tightly regulated in space and time, determines astrocyte heterogeneity.
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Affiliation(s)
- Valentina Cerrato
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Turin, Italy
| | - Elena Parmigiani
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy
| | - María Figueres-Oñate
- Department of Molecular, Cellular, and Developmental Neurobiology, Cajal Institute -CSIC-, Spanish National Research Council, Madrid, Spain
| | - Marion Betizeau
- Brain Research Institute, University of Zurich Irchel, Zurich, Switzerland
| | - Jessica Aprato
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy
| | - Ishira Nanavaty
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy
| | - Paola Berchialla
- Department of Clinical and Biological Sciences, University of Turin, Turin, Italy
| | - Federico Luzzati
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Turin, Italy
- Department of Life Sciences and System Biology, University of Turin, Turin, Italy
| | - Claudio de’Sperati
- Laboratory of Action, Perception and Cognition, Vita-Salute San Raffaele University, Milan, Italy
- Experimental Psychology Unit, Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Laura López-Mascaraque
- Department of Molecular, Cellular, and Developmental Neurobiology, Cajal Institute -CSIC-, Spanish National Research Council, Madrid, Spain
| | - Annalisa Buffo
- Department of Neuroscience Rita Levi-Montalcini, University of Turin, Turin, Italy
- Neuroscience Institute Cavalieri Ottolenghi, Orbassano, Turin, Italy
- * E-mail:
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38
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Bayin NS, Wojcinski A, Mourton A, Saito H, Suzuki N, Joyner AL. Age-dependent dormant resident progenitors are stimulated by injury to regenerate Purkinje neurons. eLife 2018; 7:39879. [PMID: 30091706 PMCID: PMC6115187 DOI: 10.7554/elife.39879] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 07/30/2018] [Indexed: 01/19/2023] Open
Abstract
Outside of the neurogenic niches of the brain, postmitotic neurons have not been found to undergo efficient regeneration. We demonstrate that mouse Purkinje cells (PCs), which are born at midgestation and are crucial for development and function of cerebellar circuits, are rapidly and fully regenerated following their ablation at birth. New PCs are produced from immature FOXP2+ Purkinje cell precursors (iPCs) that are able to enter the cell cycle and support normal cerebellum development. The number of iPCs and their regenerative capacity, however, diminish soon after birth and consequently PCs are poorly replenished when ablated at postnatal day five. Nevertheless, the PC-depleted cerebella reach a normal size by increasing cell size, but scaling of neuron types is disrupted and cerebellar function is impaired. Our findings provide a new paradigm in the field of neuron regeneration by identifying a population of immature neurons that buffers against perinatal brain injury in a stage-dependent process.
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Affiliation(s)
- N Sumru Bayin
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Alexandre Wojcinski
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Aurelien Mourton
- Developmental Biology Program, Sloan Kettering Institute, New York, United States
| | - Hiromitsu Saito
- Department of Animal Functional Genomics of Advanced Science Research Promotion Center, Organization for the Promotion of Regional Innovation, Mie University, Tsu, JAPAN
| | - Noboru Suzuki
- Department of Animal Functional Genomics of Advanced Science Research Promotion Center, Organization for the Promotion of Regional Innovation, Mie University, Tsu, JAPAN
| | - Alexandra L Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York, United States.,Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York, United States
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39
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Iskusnykh IY, Buddington RK, Chizhikov VV. Preterm birth disrupts cerebellar development by affecting granule cell proliferation program and Bergmann glia. Exp Neurol 2018; 306:209-221. [PMID: 29772246 PMCID: PMC6291230 DOI: 10.1016/j.expneurol.2018.05.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 05/09/2018] [Accepted: 05/12/2018] [Indexed: 01/17/2023]
Abstract
Preterm birth is a leading cause of long-term motor and cognitive deficits. Clinical studies suggest that some of these deficits result from disruption of cerebellar development, but the mechanisms that mediate cerebellar abnormalities in preterm infants are largely unknown. Furthermore, it remains unclear whether preterm birth and precocious exposure to the ex-utero environment directly disrupt cerebellar development or indirectly by increasing the probability of cerebellar injury, including that resulting from clinical interventions and protocols associated with the care of preterm infants. In this study, we analyzed the cerebellum of preterm pigs delivered via c-section at 91% term and raised for 10 days, until term-equivalent age. The pigs did not receive any treatments known or suspected to affect cerebellar development and had no evidence of brain damage. Term pigs sacrificed at birth were used as controls. Immunohistochemical analysis revealed that preterm birth did not affect either size or numbers of Purkinje cells or molecular layer interneurons at term-equivalent age. The number of granule cell precursors and Bergmann glial fibers, however, were reduced in preterm pigs. Preterm pigs had reduced proliferation but not differentiation of granule cells. qRT-PCR analysis of laser capture microdissected external granule cell layer showed that preterm pigs had a reduced expression of Ccnd1 (Cyclin D1), Ccnb1 (Cyclin B1), granule cell master regulatory transcription factor Atoh1, and signaling molecule Jag1. In vitro rescue experiments identified Jag1 as a central granule cell gene affected by preterm birth. Thus, preterm birth and precocious exposure to the ex-utero environment disrupt cerebellum by modulating expression of key cerebellar developmental genes, predominantly affecting development of granule precursors and Bergmann glia.
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Affiliation(s)
- Igor Y Iskusnykh
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | | | - Victor V Chizhikov
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
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40
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Cheng FY, Fleming JT, Chiang C. Bergmann glial Sonic hedgehog signaling activity is required for proper cerebellar cortical expansion and architecture. Dev Biol 2018; 440:152-166. [PMID: 29792854 DOI: 10.1016/j.ydbio.2018.05.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 05/07/2018] [Accepted: 05/18/2018] [Indexed: 01/21/2023]
Abstract
Neuronal-glial relationships play a critical role in the maintenance of central nervous system architecture and neuronal specification. A deeper understanding of these relationships can elucidate cellular cross-talk capable of sustaining proper development of neural tissues. In the cerebellum, cerebellar granule neuron precursors (CGNPs) proliferate in response to Purkinje neuron-derived Sonic hedgehog (Shh) before ultimately exiting the cell cycle and migrating radially along Bergmann glial fibers. However, the function of Bergmann glia in CGNP proliferation remains not well defined. Interestingly, the Hh pathway is also activated in Bergmann glia, but the role of Shh signaling in these cells is unknown. In this study, we show that specific ablation of Shh signaling using the tamoxifen-inducible TNCYFP-CreER line to eliminate Shh pathway activator Smoothened in Bergmann glia is sufficient to cause severe cerebellar hypoplasia and a significant reduction in CGNP proliferation. TNCYFP-CreER; SmoF/- (SmoCKO) mice demonstrate an obvious reduction in cerebellar size within two days of ablation of Shh signaling. Mutant cerebella have severely reduced proliferation and increased differentiation of CGNPs due to a significant decrease in Shh activity and concomitant activation of Wnt signaling in SmoCKO CGNPs, suggesting that this pathway is involved in cross-talk with the Shh pathway in regulating CGNP proliferation. In addition, Purkinje cells are ectopically located, their dendrites stunted, and the Bergmann glial network disorganized. Collectively, these data demonstrate a previously unappreciated role for Bergmann glial Shh signaling activity in the proliferation of CGNPs and proper maintenance of cerebellar architecture.
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Affiliation(s)
- Frances Y Cheng
- Department of Cell and Developmental Biology, Vanderbilt University, 4114 MRB III, Nashville, TN 37232, USA
| | - Jonathan T Fleming
- Department of Cell and Developmental Biology, Vanderbilt University, 4114 MRB III, Nashville, TN 37232, USA
| | - Chin Chiang
- Department of Cell and Developmental Biology, Vanderbilt University, 4114 MRB III, Nashville, TN 37232, USA.
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41
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Schilling K. Moving into shape: cell migration during the development and histogenesis of the cerebellum. Histochem Cell Biol 2018; 150:13-36. [DOI: 10.1007/s00418-018-1677-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2018] [Indexed: 12/31/2022]
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42
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Edamakanti CR, Do J, Didonna A, Martina M, Opal P. Mutant ataxin1 disrupts cerebellar development in spinocerebellar ataxia type 1. J Clin Invest 2018. [PMID: 29533923 DOI: 10.1172/jci96765] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Spinocerebellar ataxia type 1 (SCA1) is an adult-onset neurodegenerative disease caused by a polyglutamine expansion in the protein ATXN1, which is involved in transcriptional regulation. Although symptoms appear relatively late in life, primarily from cerebellar dysfunction, pathogenesis begins early, with transcriptional changes detectable as early as a week after birth in SCA1-knockin mice. Given the importance of this postnatal period for cerebellar development, we asked whether this region might be developmentally altered by mutant ATXN1. We found that expanded ATXN1 stimulates the proliferation of postnatal cerebellar stem cells in SCA1 mice. These hyperproliferating stem cells tended to differentiate into GABAergic inhibitory interneurons rather than astrocytes; this significantly increased the GABAergic inhibitory interneuron synaptic connections, disrupting cerebellar Purkinje cell function in a non-cell autonomous manner. We confirmed the increased basket cell-Purkinje cell connectivity in human SCA1 patients. Mutant ATXN1 thus alters the neural circuitry of the developing cerebellum, setting the stage for the later vulnerability of Purkinje cells to SCA1. We propose that other late-onset degenerative diseases may also be rooted in subtle developmental derailments.
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Affiliation(s)
| | - Jeehaeh Do
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | | | - Marco Martina
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Puneet Opal
- Davee Department of Neurology, and.,Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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43
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Hessel EVS, Staal YCM, Piersma AH. Design and validation of an ontology-driven animal-free testing strategy for developmental neurotoxicity testing. Toxicol Appl Pharmacol 2018; 354:136-152. [PMID: 29544899 DOI: 10.1016/j.taap.2018.03.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 02/26/2018] [Accepted: 03/11/2018] [Indexed: 12/26/2022]
Abstract
Developmental neurotoxicity entails one of the most complex areas in toxicology. Animal studies provide only limited information as to human relevance. A multitude of alternative models have been developed over the years, providing insights into mechanisms of action. We give an overview of fundamental processes in neural tube formation, brain development and neural specification, aiming at illustrating complexity rather than comprehensiveness. We also give a flavor of the wealth of alternative methods in this area. Given the impressive progress in mechanistic knowledge of human biology and toxicology, the time is right for a conceptual approach for designing testing strategies that cover the integral mechanistic landscape of developmental neurotoxicity. The ontology approach provides a framework for defining this landscape, upon which an integral in silico model for predicting toxicity can be built. It subsequently directs the selection of in vitro assays for rate-limiting events in the biological network, to feed parameter tuning in the model, leading to prediction of the toxicological outcome. Validation of such models requires primary attention to coverage of the biological domain, rather than classical predictive value of individual tests. Proofs of concept for such an approach are already available. The challenge is in mining modern biology, toxicology and chemical information to feed intelligent designs, which will define testing strategies for neurodevelopmental toxicity testing.
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Affiliation(s)
- Ellen V S Hessel
- Center for Health Protection, National Institute for Public Health and The Environment (RIVM), P.O. Box 1, 3720BA Bilthoven, The Netherlands.
| | - Yvonne C M Staal
- Center for Health Protection, National Institute for Public Health and The Environment (RIVM), P.O. Box 1, 3720BA Bilthoven, The Netherlands
| | - Aldert H Piersma
- Center for Health Protection, National Institute for Public Health and The Environment (RIVM), P.O. Box 1, 3720BA Bilthoven, The Netherlands; Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, The Netherlands
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Meis1 Coordinates Cerebellar Granule Cell Development by Regulating Pax6 Transcription, BMP Signaling and Atoh1 Degradation. J Neurosci 2018; 38:1277-1294. [PMID: 29317485 DOI: 10.1523/jneurosci.1545-17.2017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 12/12/2017] [Accepted: 12/19/2017] [Indexed: 11/21/2022] Open
Abstract
Cerebellar granule cell precursors (GCPs) and granule cells (GCs) represent good models to study neuronal development. Here, we report that the transcription factor myeloid ectopic viral integration site 1 homolog (Meis1) plays pivotal roles in the regulation of mouse GC development. We found that Meis1 is expressed in GC lineage cells and astrocytes in the cerebellum during development. Targeted disruption of the Meis1 gene specifically in the GC lineage resulted in smaller cerebella with disorganized lobules. Knock-down/knock-out (KO) experiments for Meis1 and in vitro assays showed that Meis1 binds to an upstream sequence of Pax6 to enhance its transcription in GCPs/GCs and also suggested that the Meis1-Pax6 cascade regulates morphology of GCPs/GCs during development. In the conditional KO (cKO) cerebella, many Atoh1-positive GCPs were observed ectopically in the inner external granule layer (EGL) and a similar phenomenon was observed in cultured cerebellar slices treated with a bone morphogenic protein (BMP) inhibitor. Furthermore, expression of Smad proteins and Smad phosphorylation were severely reduced in the cKO cerebella and Meis1-knock-down GCPs cerebella. Reduction of phosphorylated Smad was also observed in cerebellar slices electroporated with a Pax6 knock-down vector. Because it is known that BMP signaling induces Atoh1 degradation in GCPs, these findings suggest that the Meis1-Pax6 pathway increases the expression of Smad proteins to upregulate BMP signaling, leading to degradation of Atoh1 in the inner EGL, which contributes to differentiation from GCPs to GCs. Therefore, this work reveals crucial functions of Meis1 in GC development and gives insights into the general understanding of the molecular machinery underlying neural differentiation from neural progenitors.SIGNIFICANCE STATEMENT We report that myeloid ectopic viral integration site 1 homolog (Meis1) plays pivotal roles in the regulation of mouse granule cell (GC) development. Here, we show Meis1 is expressed in GC precursors (GCPs) and GCs during development. Our knock-down and conditional knock-out (cKO) experiments and in vitro assays revealed that Meis1 is required for proper cerebellar structure formation and for Pax6 transcription in GCPs and GCs. The Meis1-Pax6 cascade regulates the morphology of GCs. In the cKO cerebella, Smad proteins and bone morphogenic protein (BMP) signaling are severely reduced and Atoh1-expressing GCPs are ectopically detected in the inner external granule layer. These findings suggest that Meis1 regulates degradation of Atoh1 via BMP signaling, contributing to GC differentiation in the inner EGL, and should provide understanding into GC development.
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Ryan KE, Kim PS, Fleming JT, Brignola E, Cheng FY, Litingtung Y, Chiang C. Lkb1 regulates granule cell migration and cortical folding of the cerebellar cortex. Dev Biol 2017; 432:165-177. [PMID: 28974424 PMCID: PMC5694378 DOI: 10.1016/j.ydbio.2017.09.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 09/28/2017] [Accepted: 09/28/2017] [Indexed: 12/17/2022]
Abstract
Cerebellar growth and foliation require the Hedgehog-driven proliferation of granule cell precursors (GCPs) in the external granule layer (EGL). However, that increased or extended GCP proliferation generally does not elicit ectopic folds suggests that additional determinants control cortical expansion and foliation during cerebellar development. Here, we find that genetic loss of the serine-threonine kinase Liver Kinase B1 (Lkb1) in GCPs increased cerebellar cortical size and foliation independent of changes in proliferation or Hedgehog signaling. This finding is unexpected given that Lkb1 has previously shown to be critical for Hedgehog pathway activation in cultured cells. Consistent with unchanged proliferation rate of GCPs, the cortical expansion of Lkb1 mutants is accompanied by thinning of the EGL. The plane of cell division, which has been implicated in diverse processes from epithelial surface expansions to gyrification of the human cortex, remains unchanged in the mutants when compared to wild-type controls. However, we find that Lkb1 mutants display delayed radial migration of post-mitotic GCPs that coincides with increased cortical size, suggesting that aberrant cell migration may contribute to the cortical expansion and increase foliation. Taken together, our results reveal an important role for Lkb1 in regulating cerebellar cortical size and foliation in a Hedgehog-independent manner.
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Affiliation(s)
- Kaitlyn E Ryan
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA
| | - Patrick S Kim
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA
| | - Jonathan T Fleming
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA
| | - Emily Brignola
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA
| | - Frances Y Cheng
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA
| | - Ying Litingtung
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA
| | - Chin Chiang
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN 37232, USA.
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Cerebellar granule cell replenishment postinjury by adaptive reprogramming of Nestin + progenitors. Nat Neurosci 2017; 20:1361-1370. [PMID: 28805814 PMCID: PMC5614835 DOI: 10.1038/nn.4621] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 07/11/2017] [Indexed: 12/16/2022]
Abstract
Regeneration of several organs involves adaptive reprogramming of progenitors, however, the intrinsic capacity of the developing brain to replenish lost cells remains largely unknown. In this study, we discovered that the developing cerebellum has unappreciated progenitor plasticity, since it undergoes near full growth and functional recovery following acute depletion of granule cells, the most plentiful neuron population in the brain. We demonstrate that following postnatal ablation of granule cell progenitors, Nestin-expressing progenitors (NEPs) specified during mid-embryogenesis to produce astroglia and interneurons, switch their fate and generate granule neurons in mice. Moreover, Hedgehog-signaling in two NEP populations is crucial not only for the compensatory replenishment of granule neurons but also to scale interneuron and astrocyte numbers. Thus we provide insights into the mechanisms underlying robustness of circuit formation in the cerebellum, and speculate that adaptive reprogramming of progenitors in other brain regions plays a greater role than appreciated in developmental regeneration.
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Scheuer T, Sharkovska Y, Tarabykin V, Marggraf K, Brockmöller V, Bührer C, Endesfelder S, Schmitz T. Neonatal Hyperoxia Perturbs Neuronal Development in the Cerebellum. Mol Neurobiol 2017; 55:3901-3915. [PMID: 28547531 DOI: 10.1007/s12035-017-0612-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/11/2017] [Indexed: 12/22/2022]
Abstract
Impaired postnatal brain development of preterm infants often results in neurological deficits. Besides pathologies of the forebrain, maldeveolopment of the cerebellum is increasingly recognized to contribute to psychomotor impairments of many former preterm infants. However, causes are poorly defined. We used a hyperoxia model to define neonatal damage in cerebellar granule cell precursors (GCPs) and in Purkinje cells (PCs) known to be essential for interaction with GCPs during development. We exposed newborn rats to 24 h 80% O2 from age P6 to P7 to identify postnatal and long-term damage in cerebellar GCPs at age P7 after hyperoxia and also after recovery in room air thereafter until P11 and P30. We determined proliferation and apoptosis of GCPs and immature neurons by immunohistochemistry, quantified neuronal damage by qPCR and Western blots for neuronal markers, and measured dendrite outgrowth of PCs by CALB1 immunostainings and by Sholl analysis of Golgi stainings. After hyperoxia, proliferation of PAX6+ GCPs was decreased at P7, while DCX + CASP3+ cells were increased at P11. Neuronal markers Pax6, Tbr2, and Prox1 were downregulated at P11 and P30. Neuronal damage was confirmed by reduced NeuN protein expression at P30. Sonic hedgehog (SHH) was significantly decreased at P7 and P11 after hyperoxia and coincided with lower CyclinD2 and Hes1 expression at P7. The granule cell injury was accompanied by hampered PC maturation with delayed dendrite formation and impaired branching. Neonatal injury induced by hyperoxia inhibits PC functioning and impairs granule cell development. As a conclusion, maldevelopment of the cerebellar neurons found in preterm infants could be caused by postnatal oxygen toxicity.
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Affiliation(s)
- Till Scheuer
- Department for Neonatology, Charité University Medical Center, Berlin, Germany. .,Institute of Bioanalytics, Technische Universität Berlin, 13355, Berlin, Germany. .,Klinik für Neonatologie, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
| | - Yuliya Sharkovska
- Department for Neonatology, Charité University Medical Center, Berlin, Germany.,Institute for Cell and Neurobiology, Center for Anatomy, Charité University Medical Center, Berlin, Germany
| | - Victor Tarabykin
- Institute for Cell and Neurobiology, Center for Anatomy, Charité University Medical Center, Berlin, Germany
| | - Katharina Marggraf
- Department for Neonatology, Charité University Medical Center, Berlin, Germany
| | - Vivien Brockmöller
- Department for Neonatology, Charité University Medical Center, Berlin, Germany
| | - Christoph Bührer
- Department for Neonatology, Charité University Medical Center, Berlin, Germany
| | | | - Thomas Schmitz
- Department for Neonatology, Charité University Medical Center, Berlin, Germany
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48
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Heng X, Guo Q, Leung AW, Li JY. Analogous mechanism regulating formation of neocortical basal radial glia and cerebellar Bergmann glia. eLife 2017; 6. [PMID: 28489004 PMCID: PMC5457141 DOI: 10.7554/elife.23253] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 05/09/2017] [Indexed: 12/29/2022] Open
Abstract
Neocortical basal radial glia (bRG) and cerebellar Bergmann glia (BG) are basal progenitors derived from ventricular apical radial glia (aRG) that selectively lose their apical processes. bRG and BG have been implicated in the expansion and folding of the cerebrum and cerebellum, respectively. Here, we analyzed the molecular characteristics and development of bRG and BG. Transcriptomic comparison revealed striking similarity of the molecular features of bRG and BG. We found that heightened ERK signaling activity in aRG is tightly linked to the temporal formation and the relative abundance of bRG in human and mouse cortices. Forced activation of an FGF-ERK-ETV axis that is crucial to BG induction specifically induced bRG with canonical human bRG features in mice. Therefore, our data point to a common mechanism of bRG and BG generation, bearing implications to the role for these basal progenitors in the evolution of cortical folding of the cerebrum and cerebellum. DOI:http://dx.doi.org/10.7554/eLife.23253.001 The outer layer of the brain of a mammal, called the cortex, helps support mental abilities such as memory, attention and thought. In rodents, the cortex is smooth whereas in primates it is organized into folds. These folds increase the surface area of the brain and thus the number of neurons it can contain, which may in turn increase its processing power. Folding occurs as the brain develops in the womb. Specialized cells called basal or outer radial glia, which are more abundant in humans than in rodents, are believed to trigger the folding process. Another area of the brain, called the cerebellum, is intricately folded in both rodents and humans. As the brain develops, cells within the cerebellum called Bergmann glia cause the tissue to fold. Bergmann glia and basal radial glia share a number of similarities, but it was not known whether the same molecular pathway might regulate both types of cell. Now, Heng et al. show that Bergmann glia in the cerebellums of mice and basal radial glia in human cortex contain similar sets of active genes. Moreover, the molecular pathway that gives rise to Bergmann glia in mice is also active in the cortex of both mice and humans. However, it is much more active in humans, leading Heng et al. to speculate that high levels of activity in this pathway might give rise to basal radial glia. Consistent with this prediction, artificially activating the pathway at high levels in mouse cortex triggered the formation of basal radial glia in mice too. These results thus suggest that a common mechanism generates both types of glial cells involved in brain folding. The work of Heng et al. lays the foundations for further studies into how these cells fold the brain and thus how they contribute to more complex mental abilities. Remaining questions to address are whether other species with Bergmann glia also have folded cerebellums, and whether incorrect development of basal radial glia in humans leads to disorders in which the cortex folds abnormally. DOI:http://dx.doi.org/10.7554/eLife.23253.002
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Affiliation(s)
- Xin Heng
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States
| | - Qiuxia Guo
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States
| | - Alan W Leung
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States
| | - James Yh Li
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Farmington, United States.,Institute for Systems Genomics, University of Connecticut, Farmington, United States
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Hibi M, Matsuda K, Takeuchi M, Shimizu T, Murakami Y. Evolutionary mechanisms that generate morphology and neural-circuit diversity of the cerebellum. Dev Growth Differ 2017; 59:228-243. [DOI: 10.1111/dgd.12349] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 03/10/2017] [Accepted: 03/13/2017] [Indexed: 01/10/2023]
Affiliation(s)
- Masahiko Hibi
- Bioscience and Biotechnology Center; Nagoya University; Nagoya 464-8601 Japan
- Graduate School of Science; Nagoya University; Nagoya Aichi 464-8602 Japan
| | - Koji Matsuda
- Bioscience and Biotechnology Center; Nagoya University; Nagoya 464-8601 Japan
- Graduate School of Science; Nagoya University; Nagoya Aichi 464-8602 Japan
| | - Miki Takeuchi
- Bioscience and Biotechnology Center; Nagoya University; Nagoya 464-8601 Japan
| | - Takashi Shimizu
- Bioscience and Biotechnology Center; Nagoya University; Nagoya 464-8601 Japan
- Graduate School of Science; Nagoya University; Nagoya Aichi 464-8602 Japan
| | - Yasunori Murakami
- Graduate School of Science and Engineering; Ehime University; Matsuyama 790-8577 Japan
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50
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Dominici C, Moreno-Bravo JA, Puiggros SR, Rappeneau Q, Rama N, Vieugue P, Bernet A, Mehlen P, Chédotal A. Floor-plate-derived netrin-1 is dispensable for commissural axon guidance. Nature 2017; 545:350-354. [PMID: 28445456 PMCID: PMC5438598 DOI: 10.1038/nature22331] [Citation(s) in RCA: 131] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Accepted: 04/04/2017] [Indexed: 11/09/2022]
Abstract
Netrin-1 is an evolutionarily conserved, secreted extracellular matrix protein involved in axon guidance at the central nervous system midline. Netrin-1 is expressed by cells localized at the central nervous system midline, such as those of the floor plate in vertebrate embryos. Growth cone turning assays and three-dimensional gel diffusion assays have shown that netrin-1 can attract commissural axons. Loss-of-function experiments further demonstrated that commissural axon extension to the midline is severely impaired in the absence of netrin-1 (refs 3, 7, 8, 9). Together, these data have long supported a model in which commissural axons are attracted by a netrin-1 gradient diffusing from the midline. Here we selectively ablate netrin-1 expression in floor-plate cells using a Ntn1 conditional knockout mouse line. We find that hindbrain and spinal cord commissural axons develop normally in the absence of floor-plate-derived netrin-1. Furthermore, we show that netrin-1 is highly expressed by cells in the ventricular zone, which can release netrin-1 at the pial surface where it binds to commissural axons. Notably, Ntn1 deletion from the ventricular zone phenocopies commissural axon guidance defects previously described in Ntn1-knockout mice. These results show that the classical view that attraction of commissural axons is mediated by a gradient of floor-plate-derived netrin-1 is inaccurate and that netrin-1 primarily acts locally by promoting growth cone adhesion.
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Affiliation(s)
- Chloé Dominici
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France
| | - Juan Antonio Moreno-Bravo
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France
| | - Sergi Roig Puiggros
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France.,Apoptosis, Cancer and Development Laboratory, Equipe labellisée 'La Ligue', LabEx DEVweCAN, Centre de Recherche en Cancérologie de Lyon, INSERM U1052-CNRS UMR5286, Université de Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Quentin Rappeneau
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France
| | - Nicolas Rama
- Apoptosis, Cancer and Development Laboratory, Equipe labellisée 'La Ligue', LabEx DEVweCAN, Centre de Recherche en Cancérologie de Lyon, INSERM U1052-CNRS UMR5286, Université de Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Pauline Vieugue
- Apoptosis, Cancer and Development Laboratory, Equipe labellisée 'La Ligue', LabEx DEVweCAN, Centre de Recherche en Cancérologie de Lyon, INSERM U1052-CNRS UMR5286, Université de Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Agnes Bernet
- Apoptosis, Cancer and Development Laboratory, Equipe labellisée 'La Ligue', LabEx DEVweCAN, Centre de Recherche en Cancérologie de Lyon, INSERM U1052-CNRS UMR5286, Université de Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Patrick Mehlen
- Apoptosis, Cancer and Development Laboratory, Equipe labellisée 'La Ligue', LabEx DEVweCAN, Centre de Recherche en Cancérologie de Lyon, INSERM U1052-CNRS UMR5286, Université de Lyon, Centre Léon Bérard, 69008 Lyon, France
| | - Alain Chédotal
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France
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